Pathogenic bacteria

{{Infobox medical condition (new)

| name = Pathogenic bacteria

| image = Neisseria gonorrhoea in pus - Gram stain.jpg

| alt =

| caption = Neisseria gonorrhoeae (small red dots) in pus from a man with a urethral discharge (Gram stain)

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Pathogenic bacteria are bacteria that can cause disease.{{cite book|last1=Ryan|first1=Kenneth J.|last2=Ray|first2=C. George|last3=Ahmad|first3=Nafees|last4=Drew|first4=W. Lawrence|last5=Lagunoff|first5=Michael|last6=Pottinger|first6=Paul|last7=Reller|first7=L. Barth|last8=Sterling|first8=Charles R.|title=Sherris Medical Microbiology|date=2014|publisher=McGraw Hill Education|location=New York|isbn=978-0-07-181826-1|pages=391–406|edition=6th|chapter=Pathogenesis of Bacterial Infections}} This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and many are beneficial but others can cause infectious diseases. The number of these pathogenic species in humans is estimated to be fewer than a hundred.{{Cite journal|last=McFall-Ngai|first=Margaret|date=2007-01-11|title=Adaptive Immunity: Care for the community|journal=Nature|language=en|volume=445|issue=7124|pages=153|doi=10.1038/445153a|pmid=17215830|bibcode=2007Natur.445..153M|s2cid=9273396|issn=0028-0836|doi-access=free}} By contrast, several thousand species are considered part of the gut flora, with a few hundred species present in each individual human's digestive tract.{{cite journal |last1=Leviatan |first1=Sigal |last2=Shoer |first2=Saar |last3=Rothschild |first3=Daphna |last4=Gorodetski |first4=Maria |last5=Segal |first5=Eran |title=An expanded reference map of the human gut microbiome reveals hundreds of previously unknown species |journal=Nature Communications |date=2022 |volume=13 |page=3863 |url=https://www.nature.com/articles/s41467-022-31502-1 |access-date=29 April 2025}}

The body is continually exposed to many species of bacteria, including beneficial commensals, which grow on the skin and mucous membranes, and saprophytes, which grow mainly in the soil and in decaying matter. The blood and tissue fluids contain nutrients sufficient to sustain the growth of many bacteria. The body has defence mechanisms that enable it to resist microbial invasion of its tissues and give it a natural immunity or innate resistance against many microorganisms.

Pathogenic bacteria are specially adapted and endowed with mechanisms for overcoming the normal body defences, and can invade parts of the body, such as the blood, where bacteria are not normally found. Some pathogens invade only the surface epithelium, skin or mucous membrane, but many travel more deeply, spreading through the tissues and disseminating by the lymphatic and blood streams. In some rare cases a pathogenic microbe can infect an entirely healthy person, but infection usually occurs only if the body's defence mechanisms are damaged by some local trauma or an underlying debilitating disease, such as wounding, intoxication, chilling, fatigue, and malnutrition. In many cases, it is important to differentiate infection and colonization, which is when the bacteria are causing little or no harm.

File:Global number of deaths (A) and YLLs (B), by pathogen and GBD super-region, 2019.jpg (B), by pathogen and GBD super-region, 2019]]

Caused by Mycobacterium tuberculosis bacteria, one of the diseases with the highest disease burden is tuberculosis, which killed 1.4 million people in 2019, mostly in sub-Saharan Africa.{{cite web |title=Tuberculosis (TB) |url=https://www.who.int/en/news-room/fact-sheets/detail/tuberculosis |website=www.who.int |language=en}} Pathogenic bacteria contribute to other globally important diseases, such as pneumonia, which can be caused by bacteria such as Staphylococcus, Streptococcus and Pseudomonas, and foodborne illnesses, which can be caused by bacteria such as Shigella, Campylobacter, and Salmonella. Pathogenic bacteria also cause infections such as tetanus, typhoid fever, diphtheria, syphilis, and leprosy.

Pathogenic bacteria are also the cause of high infant mortality rates in developing countries.{{cite journal|last1=Santosham|first1=Mathuram|last2=Chan|first2=Grace J.|last3=Lee|first3=Anne CC|last4=Baqui|first4=Abdullah H.|last5=Tan|first5=Jingwen|last6=Black|first6=Robert E.|title=Risk of Early-Onset Neonatal Infection with Maternal Infection or Colonization: A Global Systematic Review and Meta-Analysis|journal=PLOS Medicine|volume=10|issue=8|year=2013|pages=e1001502|issn=1549-1676|doi=10.1371/journal.pmed.1001502|pmid=23976885|pmc=3747995 |doi-access=free }} A GBD study estimated the global death rates from (33) bacterial pathogens, finding such infections contributed to one in 8 deaths (or ~7.7 million deaths), which {{tooltip|could make it|when "Compared with GBD Level 3 underlying causes of death"}} the second largest cause of death globally in 2019.{{cite news |last1=Hou |first1=Chia-Yi |title=Bacterial infections linked to 1 in 8 deaths in 2019 |url=https://thehill.com/changing-america/well-being/prevention-cures/3748033-bacterial-infections-linked-to-1-in-8-deaths-in-2019/ |access-date=12 December 2022 |work=The Hill |date=23 November 2022}}{{cite journal |last1=Ikuta |first1=Kevin S. |last2=Swetschinski |first2=Lucien R. |last3=Aguilar |first3=Gisela Robles |last4=Sharara |first4=Fablina |last5=Mestrovic |first5=Tomislav |last6=Gray |first6=Authia P. |last7=Weaver |first7=Nicole Davis |last8=Wool |first8=Eve E. |display-authors=et al. |title=Global mortality associated with 33 bacterial pathogens in 2019: a systematic analysis for the Global Burden of Disease Study 2019 |journal=The Lancet |date=21 November 2022 |volume=400 |issue=10369 |pages=2221–2248 |doi=10.1016/S0140-6736(22)02185-7 |pmid=36423648 |pmc=9763654 |language=English |issn=0140-6736 |doi-access=free}}

Most pathogenic bacteria can be grown in cultures and identified by Gram stain and other methods. Bacteria grown in this way are often tested to find which antibiotics will be an effective treatment for the infection. For hitherto unknown pathogens, Koch's postulates are the standard to establish a causative relationship between a microbe and a disease.

Diseases

File:Commensals vs pathogens mechanism.pngs vs pathogenic bacteria in COPD]]

Each species has specific effect and causes symptoms in people who are infected. Some people who are infected with a pathogenic bacteria do not have symptoms. Immunocompromised individuals are more susceptible to pathogenic bacteria.{{cite journal |vauthors=Azoulay E, Russell L, Van de Louw A, Metaxa V, Bauer P, Povoa P, Montero JG, Loeches IM, Mehta S, Puxty K, Schellongowski P, Rello J, Mokart D, Lemiale V, Mirouse A |title=Diagnosis of severe respiratory infections in immunocompromised patients |journal=Intensive Care Medicine |volume=46 |issue=2 |pages=298–314 |date=February 2020 |pmid=32034433 |pmc=7080052 |doi=10.1007/s00134-019-05906-5 |url=}}

=Pathogenic susceptibility=

Some pathogenic bacteria cause disease under certain conditions, such as entry through the skin via a cut, through sexual activity or through compromised immune function.{{citation needed|date=June 2021}}

File:Cutaneous abscess MRSA staphylococcus aureus 7826 lores.jpg

Some species of Streptococcus and Staphylococcus are part of the normal skin microbiota and typically reside on healthy skin or in the nasopharyngeal region. Yet these species can potentially initiate skin infections. Streptococcal infections include sepsis, pneumonia, and meningitis.{{cite web |title=Streptococcal Infections - Infectious Diseases |url=https://www.msdmanuals.com/professional/infectious-diseases/gram-positive-cocci/streptococcal-infections |website=MSD Manual Professional Edition |access-date=2 May 2021 |language=en}} These infections can become serious creating a systemic inflammatory response resulting in massive vasodilation, shock, and death.{{cite journal |author=Fish DN |title=Optimal antimicrobial therapy for sepsis |journal=Am J Health Syst Pharm |volume=59 |issue=Suppl 1 |pages=S13–9 |date=February 2002 |pmid=11885408 |url=http://www.ajhp.org/cgi/pmidlookup?view=long&pmid=11885408|doi=10.1093/ajhp/59.suppl_1.S13 |doi-access=free }}

Other bacteria are opportunistic pathogens and cause disease mainly in people with immunosuppression or cystic fibrosis. Examples of these opportunistic pathogens include Pseudomonas aeruginosa, Burkholderia cenocepacia, and Mycobacterium avium.{{cite journal | author = Heise E | title = Diseases associated with immunosuppression | pmc=1568899 | journal = Environ Health Perspect | volume = 43 |pages=9–19 |year=1982 |pmid=7037390 |doi=10.2307/3429162 | jstor=3429162}}{{cite journal |author=Saiman L |title=Microbiology of early CF lung disease |journal=Paediatr Respir Rev |volume=5 |issue=Suppl A |pages=S367–9 |year=2004 |pmid=14980298 |doi=10.1016/S1526-0542(04)90065-6}}

=Intracellular=

Obligate intracellular parasites (e.g. Chlamydophila, Ehrlichia, Rickettsia) are only able to grow and replicate inside other cells. Infections due to obligate intracellular bacteria may be asymptomatic, requiring an incubation period. Examples of obligate intracellular bacteria include Rickettsia prowazekii (typhus) and Rickettsia rickettsii, (Rocky Mountain spotted fever).{{citation needed|date=June 2021}}

Chlamydia are intracellular parasites. These pathogens can cause pneumonia or urinary tract infection and may be involved in coronary heart disease.{{cite journal |vauthors=Belland R, Ouellette S, Gieffers J, Byrne G | title = Chlamydia pneumoniae and atherosclerosis | journal = Cell Microbiol | volume = 6 |issue=2 |pages=117–27 |year=2004 |pmid=14706098 |doi=10.1046/j.1462-5822.2003.00352.x| s2cid = 45218449 |doi-access=free }}

Other groups of intracellular bacterial pathogens include Salmonella, Neisseria, Brucella, Mycobacterium, Nocardia, Listeria, Francisella, Legionella, and Yersinia pestis. These can exist intracellularly, but can exist outside host cells.{{citation needed|date=June 2021}}

=Infections in specific tissue=

Bacterial pathogens often cause infection in specific areas of the body. Others are generalists.

Bacterial vaginosis is a condition of the vaginal microbiota in which an excessive growth of Gardnerella vaginalis and other mostly anaerobic bacteria displace the beneficial Lactobacilli species that maintain healthy vaginal microbial populations.{{cite journal |vauthors=Muzny CA, Schwebke JR |title=Pathogenesis of Bacterial Vaginosis: Discussion of Current Hypotheses |journal=The Journal of Infectious Diseases |volume=214 |issue= Suppl 1|pages=S1–5 |date=August 2016 |pmid=27449868 |pmc=4957507 |doi=10.1093/infdis/jiw121 |url=}}
Bacterial meningitis is a bacterial inflammation of the meninges, which are the protective membranes covering the brain and spinal cord.
Bacterial pneumonia is a bacterial infection of the lungs.
Urinary tract infection is predominantly caused by bacteria. Symptoms include the strong and frequent sensation or urge to urinate, pain during urination, and urine that is cloudy.{{cite web|url=http://www.medicinenet.com/urine_infection/page4.htm|title=Urinary Tract Infections|access-date=2010-02-04 }} The most frequent cause is Escherichia coli. Urine is typically sterile but contains a variety of salts and waste products. Bacteria can ascend into the bladder or kidney and causing cystitis and nephritis.Roxe DM. Urinalysis. In: Walker HK, Hall WD, Hurst JW, editors. Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition. Boston: Butterworths; 1990. Chapter 191. Available from: https://www.ncbi.nlm.nih.gov/books/NBK302/{{cite journal |vauthors=Hollyer I, Ison MG |title=The challenge of urinary tract infections in renal transplant recipients |journal=Transplant Infectious Disease |volume=20 |issue=2 |pages=e12828 |date=April 2018 |pmid=29272071 |doi=10.1111/tid.12828 |s2cid=4724463 |url=|doi-access=free }}
Bacterial gastroenteritis is caused by enteric, pathogenic bacteria. These pathogenic species are usually distinct from the usually harmless bacteria of the normal gut flora. But a different strain of the same species may be pathogenic. The distinction is sometimes difficult as in the case of Escherichia.
Bacterial skin infections include:
Impetigo is a highly contagious bacterial skin infection commonly seen in children.{{cite web|url=http://www.nhs.uk/conditions/Impetigo/Pages/Introduction.aspx|title=Impetigo|website=National Health Service|date=19 October 2017}} Page last reviewed: 17/07/2014 It is caused by Staphylococcus aureus, and Streptococcus pyogenes.Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; & Mitchell, Richard N. (2007). Robbins Basic Pathology (8th ed.). Saunders Elsevier. pp. 843 {{ISBN|978-1-4160-2973-1}}
Erysipelas is an acute streptococcus bacterial infection{{DorlandsDict|three/000036667|erysipelas}} of the deeper skin layers that spreads via with lymphatic system.
Cellulitis is a diffuse inflammation{{DorlandsDict|two/000019077|cellulitis}} of connective tissue with severe inflammation of dermal and subcutaneous layers of the skin. Cellulitis can be caused by normal skin flora or by contagious contact, and usually occurs through open skin, cuts, blisters, cracks in the skin, insect bites, animal bites, burns, surgical wounds, intravenous drug injection, or sites of intravenous catheter insertion. In most cases it is the skin on the face or lower legs that is affected, though cellulitis can occur in other tissues.

Mechanisms of damage

The symptoms of disease appear as pathogenic bacteria damage host tissues or interfere with their function. The bacteria can damage host cells directly or indirectly by provoking an immune response that inadvertently damages host cells,{{cite book|last1=Greenwood|first1=David|last2=Barer|first2=Mike|last3=Slack|first3=Richard|last4=Irving|first4=Will|title=Medical Microbiology, a Guide to Microbial Infections: Pathogenesis, Immunity, Laboratory Investigation, and Control|date=2012|publisher=Churchill Livingstone|location=Edinburgh|isbn=9780702040894|pages=156–167|edition=18th|chapter=Bacterial Pathogenicity}} or by releasing toxins.{{cite journal |vauthors=Rudkin JK, McLoughlin RM, Preston A, Massey RC |title=Bacterial toxins: Offensive, defensive, or something else altogether? |journal=PLOS Pathogens |volume=13 |issue=9 |pages=e1006452 |date=September 2017 |pmid=28934339 |pmc=5608399 |doi=10.1371/journal.ppat.1006452 |url= |doi-access=free }}

=Direct=

Once pathogens attach to host cells, they can cause direct damage as the pathogens use the host cell for nutrients and produce waste products.{{cite book|last1=Tortora|first1=Gerald J.|last2=Funke|first2=Berdell R.|last3=Case|first3=Christine L.|title=Microbiology, an Introduction|date=2016|publisher=Pearson Education|isbn=978-0-321-92915-0|pages=417–438|edition=12th|chapter=Microbial Mechanisms of Pathogenicity}} For example, Streptococcus mutans, a component of dental plaque, metabolizes dietary sugar and produces acid as a waste product. The acid decalcifies the tooth surface to cause dental caries.{{cite book|last1=Nash|first1=Anthony A.|last2=Dalziel|first2=Robert G.|last3=Fitzgerald|first3=J. Ross|title=Mims' Pathogenesis of Infectious Disease|date=2015|publisher=Academic Press|location=London|isbn=978-0-12-397188-3|pages=171–231|edition=6th|chapter=Mechanisms of Cell and Tissue Damage}}

==Toxin production==

File:Botulinum toxin 3BTA.png of botulinum toxin.]]

Endotoxins are the lipid portions of lipopolysaccharides that are part of the outer membrane of the cell wall of gram-negative bacteria. Endotoxins are released when the bacteria lyses, which is why after antibiotic treatment, symptoms can worsen at first as the bacteria are killed and they release their endotoxins. Exotoxins are secreted into the surrounding medium or released when the bacteria die and the cell wall breaks apart.

=Indirect=

An excessive or inappropriate immune response triggered by an infection may damage host cells.

Survival in host

=Nutrients=

Iron is required for humans, as well as the growth of most bacteria. To obtain free iron, some pathogens secrete proteins called siderophores, which take the iron away from iron-transport proteins by binding to the iron even more tightly. Once the iron-siderophore complex is formed, it is taken up by siderophore receptors on the bacterial surface and then that iron is brought into the bacterium.{{cite book |last=Tortota |first=Gerard |date=2013 |title=Microbiology an Introduction |publisher=Pearson |isbn=978-0-321-73360-3 }}

Bacterial pathogens also require access to carbon and energy sources for growth. To avoid competition with host cells for glucose which is the main energy source used by human cells, many pathogens including the respiratory pathogen Haemophilus influenzae specialise in using other carbon sources such as lactate that are abundant in the human body {{Cite journal|last1=Hosmer|first1=Jennifer|last2=Nasreen|first2=Marufa|last3=Dhouib|first3=Rabeb|last4=Essilfie|first4=Ama-Tawiah|last5=Schirra|first5=Horst Joachim|last6=Henningham|first6=Anna|last7=Fantino|first7=Emmanuelle|last8=Sly|first8=Peter|last9=McEwan|first9=Alastair G.|last10=Kappler|first10=Ulrike|date=2022-01-27|title=Access to highly specialized growth substrates and production of epithelial immunomodulatory metabolites determine survival of Haemophilus influenzae in human airway epithelial cells|journal=PLOS Pathogens|language=en|volume=18|issue=1|pages=e1010209|doi=10.1371/journal.ppat.1010209|pmid=35085362 |issn=1553-7374|pmc=8794153 |doi-access=free }}

Identification

File:Diagnostic algorithm of possible bacterial infection.png

Typically identification is done by growing the organism in a wide range of cultures which can take up to 48 hours. The growth is then visually or genomically identified. The cultured organism is then subjected to various assays to observe reactions to help further identify species and strain.{{cite book |vauthors=Cassells AC |title=Plant Cell Culture Protocols |chapter=Pathogen and Biological Contamination Management in Plant Tissue Culture: Phytopathogens, Vitro Pathogens, and Vitro Pests |series=Methods in Molecular Biology |volume=877 |pages=57–80 |year=2012 |pmid=22610620 |doi=10.1007/978-1-61779-818-4_6 |isbn=978-1-61779-817-7 }}

Treatment

{{See also|Pathogenic bacteria#List of species of pathogenic bacteria and clinical characteristics|l1=overview list below}}

Bacterial infections may be treated with antibiotics, which are classified as bacteriocidal if they kill bacteria or bacteriostatic if they just prevent bacterial growth. There are many types of antibiotics and each class inhibits a process that is different in the pathogen from that found in the host. For example, the antibiotics chloramphenicol and tetracyclin inhibit the bacterial ribosome but not the structurally different eukaryotic ribosome, so they exhibit selective toxicity.{{cite journal |vauthors=Yonath A, Bashan A | title = Ribosomal crystallography: initiation, peptide bond formation, and amino acid polymerization are hampered by antibiotics |journal=Annu Rev Microbiol |volume=58 |pages=233–51 |year=2004 |pmid=15487937 |doi=10.1146/annurev.micro.58.030603.123822|doi-access=free }} Antibiotics are used both in treating human disease and in intensive farming to promote animal growth. Both uses may be contributing to the rapid development of antibiotic resistance in bacterial populations.{{cite journal |author=Khachatourians GG |title=Agricultural use of antibiotics and the evolution and transfer of antibiotic-resistant bacteria |journal=CMAJ |volume=159 |issue=9 |pages=1129–36 |date=November 1998 |pmid=9835883 |pmc=1229782 |url=http://www.cmaj.ca/cgi/pmidlookup?view=reprint&pmid=9835883}} Phage therapy, using bacteriophages can also be used to treat certain bacterial infections.{{Cite journal | last1 = Keen | first1 = E. C. | title = Phage Therapy: Concept to Cure | doi = 10.3389/fmicb.2012.00238 | journal = Frontiers in Microbiology | volume = 3 | pages = 238 | year = 2012 | pmid = 22833738| pmc = 3400130| doi-access = free }}

Prevention

Infections can be prevented by antiseptic measures such as sterilizing the skin prior to piercing it with the needle of a syringe and by proper care of indwelling catheters. Surgical and dental instruments are also sterilized to prevent infection by bacteria. Disinfectants such as bleach are used to kill bacteria or other pathogens on surfaces to prevent contamination and further reduce the risk of infection. Bacteria in food are killed by cooking to temperatures above 73 °C (163 °F).{{citation needed|date=June 2021}}

List of genera and microscopy features

Many genera contain pathogenic bacterial species. They often possess characteristics that help to classify and organize them into groups. The following is a partial listing.

Genus ! Species ! Gram staining ! Shape ! Oxygen requirement ! Intra/Extracellular
class="wikitable sortable" style="font-size:0.8em;"
BacillusUnless else specified in boxes then ref is: {{cite book \|author1=Fisher, Bruce \|author2=Harvey, Richard P. \|author3=Champe, Pamela C. \|title=Lippincott's Illustrated Reviews: Microbiology (Lippincott's Illustrated Reviews Series) \|publisher=Lippincott Williams & Wilkins \|location=Hagerstown, MD \|year= 2007\|pages=332–353 \|isbn=978-0-7817-8215-9 }} \| Bacillus anthracis Bacillus cereus \| Positive \| Rods \| Facultative anaerobic \| Extracellular
Bartonella \| Bartonella henselae Bartonella quintana \| Negative \| Rods \| Aerobic \| Facultative intracellular
Bordetella \| Bordetella pertussis{{cite journal \|vauthors=Kurzynski TA, Boehm DM, Rott-Petri JA, Schell RF, Allison PE \|title=Comparison of modified Bordet-Gengou and modified Regan-Lowe media for the isolation of Bordetella pertussis and Bordetella parapertussis \|journal=J. Clin. Microbiol. \|volume=26 \|issue=12 \|pages=2661–3 \|year=1988 \|doi=10.1128/JCM.26.12.2661-2663.1988 \|pmid=2906642 \|pmc=266968 }}{{cite book \|author1=Fisher, Bruce \|author2=Harvey, Richard P. \|author3=Champe, Pamela C. \|title=Lippincott's Illustrated Reviews: Microbiology (Lippincott's Illustrated Reviews Series) \|publisher=Lippincott Williams & Wilkins \|location=Hagerstown, MD \|year= 2007\|pages=332–353 \|isbn=978-0-7817-8215-9 }} \| Negative \| Small coccobacilli \| Aerobic \| Extracellular
Borrelia \| Borrelia burgdorferi Borrelia garinii Borrelia afzelii Borrelia recurrentis \| Negative, stains poorly \| Spirochete \| Anaerobic \| Extracellular
Brucella \| Brucella abortus Brucella canis Brucella melitensis Brucella suis \| Negative \| Coccobacilli \| Aerobic \| Intracellular
Campylobacter \| Campylobacter jejuni \| Negative \| Spiral rods{{cite journal \|vauthors=Epps SV, Harvey RB, Hume ME, Phillips TD, Anderson RC, Nisbet DJ \|title=Foodborne Campylobacter: infections, metabolism, pathogenesis and reservoirs \|journal=International Journal of Environmental Research and Public Health \|volume=10 \|issue=12 \|pages=6292–304 \|year=2013 \|pmid=24287853 \|pmc=3881114 \|doi=10.3390/ijerph10126292 \|doi-access=free }} coccoid in older cultures \| Microaerophilic \| Extracellular
Chlamydia and Chlamydophila \| Chlamydia pneumoniae Chlamydia trachomatis Chlamydophila psittaci \| (not Gram-stained) \| Small, round, ovoid \| Facultative or strictly aerobic \| Obligate intracellular
Clostridium \| Clostridium botulinum Clostridioides difficile Clostridium perfringens Clostridium tetani \| Positive \| Large, blunt-ended rods \| Obligate anaerobic \| Extracellular
Corynebacterium \| Corynebacterium diphtheriae{{cite book\|first=Samuel\|last=Baron\|title=Medical Microbiology\|edition=4th\|date=1996\|isbn= 978-0-9631172-1-2\|publisher=University of Texas Medical Branch at Galveston, Galveston, Texas}} \| Positive (unevenly) \| Rods \| Mostly facultative anaerobic \| Extracellular
Enterococcus{{cite web \|url=http://www.life.umd.edu/classroom/bsci424/LabMaterialsMethods/BSCI424Media.htm \|title=BSCI424 Laboratory Media \|access-date=2008-11-18\|first=David M.\|last=Rollins\|date=2000\|publisher=University of Maryland}} \| Enterococcus faecalis Enterococcus faecium \| Positive \| Cocci \| Facultative Anaerobic \| Extracellular
Escherichia{{cite web\|url=http://iws2.collin.edu/dcain/CCCCD%20Micro/macconkeyagar.htm\|title=MacConkey Agar (CCCCD Microbiology\|first=Donna\|last=Cain\|date=January 14, 2015\|publisher=Collin College\|access-date=May 3, 2015\|archive-url=https://web.archive.org/web/20150426154407/http://iws2.collin.edu/dcain/CCCCD%20Micro/macconkeyagar.htm\|archive-date=April 26, 2015\|url-status=dead}} \| Escherichia coli \| Negative \| Rods \| Facultative anaerobic \| Extracellular or Intracellular
Francisella \| Francisella tularensis \| Negative \| Coccobacillus \| Strictly aerobic \| Facultative intracellular
Haemophilus \| Haemophilus influenzae{{cite journal \|vauthors=Gunn BA \|title=Chocolate agar, a differential medium for gram-positive cocci \|journal=Journal of Clinical Microbiology \|volume=20 \|issue=4 \|pages=822–3 \|year=1984 \|doi=10.1128/JCM.20.4.822-823.1984 \|pmid=6490866 \|pmc=271442 \|url=}} \| Negative \| Coccobacilli to long and slender filaments \|Facultative anaerobic 5 - 10% CO2 \| Extracellular
Helicobacter \| Helicobacter pylori{{cite journal \|vauthors=Stevenson TH, Castillo A, Lucia LM, Acuff GR \|title=Growth of Helicobacter pylori in various liquid and plating media \|journal=Lett. Appl. Microbiol. \|volume=30 \|issue=3 \|pages=192–6 \|year=2000 \|pmid=10747249 \|doi= 10.1046/j.1472-765x.2000.00699.x\|s2cid=24668819 \|doi-access=free }} \| Negative \| Spiral rod \| Microaerophile \| Extracellular
Legionella \| Legionella pneumophila \| Negative, stains poorly \| Cocobacilli \| Aerobic \| Facultative intracellular
Leptospira{{cite journal \|vauthors=Johnson RC, Harris VG \|title=Differentiation of Pathogenic and Saprophytic Leptospires I. Growth at Low Temperatures \|journal=J. Bacteriol. \|volume=94 \|issue=1 \|pages=27–31 \|year=1967 \|doi=10.1128/JB.94.1.27-31.1967 \|pmid=6027998 \|pmc=251866}} \| Leptospira interrogans Leptospira santarosai Leptospira weilii Leptospira noguchii \| Negative, stains poorly \| Spirochete \| Strictly aerobic \| Extracellular
Listeria \| Listeria monocytogenes \| Positive, darkly \| Slender, short rods \| Facultative Anaerobic \| Facultative intracellular
Mycobacterium \| Mycobacterium leprae Mycobacterium tuberculosis Mycobacterium ulcerans \| (none) \| Long, slender rods \| Aerobic \| Intracellular
Mycoplasma \| Mycoplasma pneumoniae \| (none) \| Indistinct 'fried egg' appearance, no cell wall \| Mostly facultative anaerobic; M. pneumoniae strictly aerobic \| Extracellular
Neisseria{{cite web\|url=http://webmedia.unmc.edu/alliedhealth/CLS/CLS418%2008/Thayer%20Martin%20Agar%20Procedure%2008.pdf\|title=Thayer Martin Agar (Modified) Procedure\|publisher=University of Nebraska-Medical Center, Clinical Laboratory Science Program\|access-date=2015-05-03}} \| Neisseria gonorrhoeae Neisseria meningitidis \| Negative \| Kidney bean-shaped \| Aerobic \| Gonococcus: facultative intracellular N. meningitidis: extracellular
Pseudomonas{{cite web\|url=http://www.microbelibrary.org/component/resource/laboratory-test/2855-macconkey-agar-plates-protocols\|title=MacConkey Agar Plates Protocols\|publisher=American Society for Microbiology\|year=2005\|first=Mary E.\|last=Allen\|url-status=dead\|archive-url=https://web.archive.org/web/20150507033028/http://www.microbelibrary.org/component/resource/laboratory-test/2855-macconkey-agar-plates-protocols\|archive-date=2015-05-07}} Created: 30 September 2005. Last update: 01 April 2013 \| Pseudomonas aeruginosa \| Negative \| Rods \| Obligate aerobic \| Extracellular
Rickettsia \| Rickettsia rickettsii \| Negative, stains poorly \| Small, rod-like coccobacillary \| Aerobic \| Obligate intracellular
Salmonella \| Salmonella typhi Salmonella typhimurium \| Negative \| Rods \| Facultative anaerobic \| Facultative intracellular
Shigella{{cite web\|url=http://www.austincc.edu/microbugz/hektoen_enteric_agar.php\|title=Hektoen Enteric Agar\|publisher=Austin Community College District\|access-date=2015-05-03}} \| Shigella sonnei \| Negative \| Rods \| Facultative anaerobic \| Extracellular
Staphylococcus \| Staphylococcus aureus Staphylococcus epidermidis Staphylococcus saprophyticus \| Positive, darkly \| Round cocci \| Facultative anaerobic \| Extracellular, facultative intracellular
Streptococcus \| Streptococcus agalactiae Streptococcus pneumoniae Streptococcus pyogenes \| Positive \| Ovoid to spherical \| Facultative anaerobic \| Extracellular
Treponema \| Treponema pallidum \| Negative, stains poorly \| Spirochete \| Aerobic \| Extracellular
Ureaplasma \| Ureaplasma urealyticum \| Stains poorly{{cite journal \|vauthors=Cassell GH, Waites KB, Crouse DT, Rudd PT, Canupp KC, Stagno S, Cutter GR \|title=Association of Ureaplasma urealyticum infection of the lower respiratory tract with chronic lung disease and death in very-low-birth-weight infants \|journal=Lancet \|volume=2 \|issue=8605 \|pages=240–5 \|year=1988 \|pmid=2899235 \|doi= 10.1016/s0140-6736(88)92536-6\|s2cid=6685738 }} \|Indistinct, 'fried egg' appearance, no cell wall \|Anaerobic \|Extracellular
Vibrio{{cite journal \|last1=Pfeffer \|first1=C. \|last2=Oliver \|first2=J.D. \|year=2003 \|title= A comparison of thiosulphate-citrate-bile salts-sucrose (TCBS) agar and thiosulphate-chloride-iodide (TCI) agar for the isolation of Vibrio species from estuarine environments \|journal=Letters in Applied Microbiology \|volume=36 \|pmid=12581373 \|issue=3 \|pages=150–151 \|doi=10.1046/j.1472-765X.2003.01280.x\|s2cid=34004290 \|doi-access=free }} \| Vibrio cholerae \| Negative \| Spiral with single polar flagellum \| Facultative anaerobic \| Extracellular
Yersinia{{cite web\|url=http://www.health.ny.gov/guidance/oph/wadsworth/yersinia_pestis.pdf\|title=Yersinia pestis\|publisher=Wadsworth Center\|date=2006}} \| Yersinia pestis Yersinia enterocolitica Yersinia pseudotuberculosis \| Negative, bipolarly \| Small rods \| Facultative anaerobe \| Intracellular

List of species and clinical characteristics

File:Overall age-standardised mortality rate per 100 000 population for 33 pathogens investigated, 2019.jpg|Overall age-standardised mortality rate per 100 000 population for 33 pathogens investigated, 2019

File:Global number of deaths (A) and YLLs (B), by pathogen and infectious syndrome, 2019.jpg|Global number of deaths (A) and YLLs (B), by pathogen and infectious syndrome, 2019

File:Global number of deaths, by pathogen, age, and sex groups, 2019.jpg|Global number of deaths, by pathogen, age, and sex groups, 2019

This is description of the more common genera and species presented with their clinical characteristics and treatments.

class="wikitable" style="font-size:0.9em;" \|+Species of human pathogenic bacteria
style="width: 14%" colspan=2\| Species !style="width: 25%"\| Transmission !style="width: 22%"\| Diseases !style="width: 15%"\| Treatment !style="width: 24%"\| Prevention
colspan=2\| Actinomyces israelii \| Oral flora \| Actinomycosis: painful abscesses and cysts MRSA in the mouth, lungs,{{cite journal\|last=Brook\|first=I\|title=Actinomycosis: diagnosis and management.\|journal=Southern Medical Journal\|date=Oct 2008\|volume=101\|issue=10\|pages=1019–23\|pmid=18791528\|doi=10.1097/SMJ.0b013e3181864c1f\|s2cid=19554893}}{{cite journal \| last=Mabeza \| first=GF \|author2= Macfarlane J \| title=Pulmonary actinomycosis \| journal=European Respiratory Journal \| volume=21 \| issue=3 \| pages=545–551 \| date=March 2003 \| pmid=12662015 \| doi=10.1183/09031936.03.00089103 \| doi-access=free }} or gastrointestinal tract.{{cite book \| author = Bowden GHW \| title = Actinomycosis in: Baron's Medical Microbiology\| editor = Baron S\| display-editors = etal\| edition = 4th \| publisher = Univ of Texas Medical Branch \| year = 1996 \| id = [https://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mmed.section.1883 (via NCBI Bookshelf)] \| isbn = 978-0-9631172-1-2 }} \| Prolonged penicillin G and drainage \|
colspan=2\| Bacillus anthracis \| Contact with cattle, sheep, goats and horses{{cite web \|url=http://www.fao.org/ag/magazine/0112sp.htm \|title=Anthrax in animals \|date=2001 \|publisher=Food and Agriculture Organization }} Spores enter through inhalation or through abrasions \| Anthrax: pulmonary, gastrointestinal and/or cutaneous symptoms.{{cite web\|title=Bacteria Table\|url=http://medschool.creighton.edu/fileadmin/user/medicine/MMI/Files/Bacteria_Table.pdf\|publisher=Creighton University School of Medicine\|access-date=2015-05-03\|url-status=dead\|archive-url=https://web.archive.org/web/20150501071840/http://medschool.creighton.edu/fileadmin/user/medicine/MMI/Files/Bacteria_Table.pdf\|archive-date=2015-05-01}} \| In early infection:{{cite web\|url=http://emergency.cdc.gov/agent/anthrax/faq/treatment.asp\|title=CDC Anthrax Q & A: Treatment\|access-date=4 April 2011\|archive-url=https://web.archive.org/web/20110505191339/http://emergency.cdc.gov/agent/anthrax/faq/treatment.asp\|archive-date=5 May 2011\|url-status=dead}} Penicillin Doxycycline Ciprofloxacin Raxibacumab{{cite web \|url=https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm332341.htm \|archive-url=https://web.archive.org/web/20121217061133/http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm332341.htm \|url-status=dead \|archive-date=December 17, 2012 \|title=FDA approves raxibacumab to treat inhalational anthrax\|website=Food and Drug Administration\|access-date=14 December 2012}} \| Anthrax vaccine Autoclaving of equipment
colspan=2\| Bacteroides fragilis \| Gut flora \| Abscesses in gastrointestinal tract, pelvic cavity and lungs \| metronidazole \| Wound care{{cite web\|title=Bacteroides Infection Follow-up\|url=http://emedicine.medscape.com/article/233339-followup\|publisher=Medscape\|author=Itzhak Brook\|date=Jan 28, 2014\|access-date=2015-09-25}} Aspiration prevention
colspan=2\| Bordetella pertussis \| Contact with respiratory droplets expelled by infected human hosts. \| Whooping cough Secondary bacterial pneumonia \|Macrolides such as erythromycin, before paroxysmal stage \| Pertussis vaccine, such as in DPT vaccine
rowspan=2\|Borrelia \|B. burgdorferi B. garinii B. afzelii \| Ixodes hard ticks Reservoir in mice, other small mammals, and birds{{cite journal \|vauthors=Shapiro ED \|title=Clinical practice. Lyme disease \|journal=The New England Journal of Medicine \|volume=370 \|issue=18 \|pages=1724–31 \|year=2014 \|pmid=24785207 \|pmc=4487875 \|doi=10.1056/NEJMcp1314325 }} \| Lyme disease{{cite journal \|vauthors=Sanchez JL \|title=Clinical Manifestations and Treatment of Lyme Disease \|journal=Clinics in Laboratory Medicine \|volume=35 \|issue=4 \|pages=765–78 \|year=2015 \|pmid=26593256 \|doi=10.1016/j.cll.2015.08.004 }}{{cite journal \|vauthors=Halperin JJ \|title=Nervous System Lyme Disease \|journal=Clinics in Laboratory Medicine \|volume=35 \|issue=4 \|pages=779–95 \|year=2015 \|pmid=26593257 \|doi=10.1016/j.cll.2015.07.002 }} Early localized: erythema migrans Early disseminated: neuroborreliosis, Lyme carditis Late: Lyme arthritis, Achrodermatitis chronica (B. afzelii only) \| Doxycycline for adults, amoxicillin for children, ceftriaxone for neurological involvement \| Wearing clothing that limits skin exposure to ticks. Insect repellent. Avoid areas where ticks are found.
B. recurrentis{{cite book\|last1=Barbour\|first1=Alan G.\|editor1-last=Kasper\|editor1-first=Dennis L.\|editor2-last=Fauci\|editor2-first=Anthony S.\|title=Harrison's Infectious Diseases\|date=2017\|publisher=McGraw Hill Education\|location=New York\|isbn=978-1-259-83597-1\|pages=678–687\|edition=3rd\|chapter=Relapsing Fever}} and others \| Pediculus humanus corporis body louse (B. recurrentis only) and Ornithodoros soft ticks \| Relapsing fever \| Penicillin, tetracycline, doxycycline{{cite journal \|vauthors=Cutler SJ \|title=Relapsing Fever Borreliae: A Global Review \|journal=Clinics in Laboratory Medicine \|volume=35 \|issue=4 \|pages=847–65 \|year=2015 \|pmid=26593261 \|doi=10.1016/j.cll.2015.07.001 }} \| Avoid areas where ticks are found Better access to washing facilities Reduce crowding Pesticides
Brucella \|B. abortus B. canis B. melitensis B. suis \| Direct contact with infected animal Oral, by ingestion of unpasteurized milk or milk products \| Brucellosis: mainly fever, muscular pain and night sweats \| doxycycline streptomycin or gentamicin \|
colspan=2\|Campylobacter jejuni \| Fecal–oral from animals (mammals and fowl) Uncooked meat (especially poultry) Contaminated water \| Enteritis, bloody diarrhea Guillain–Barré syndrome (muscle weakness) \| Treat symptoms Fluoroquinolone such as ciprofloxacin in severe cases \| Good hygiene Avoiding contaminated water Pasteurizing milk and milk products Cooking meat (especially poultry)
rowspan=2\| Chlamydia \|C. pneumoniae \| Respiratory droplets \| Atypical pneumonia \| Doxycycline Erythromycin \| None
C. trachomatis \| vaginal sex oral sex anal sex Vertical from mother to newborn(ICN) Direct or contaminated surfaces and flies (trachoma) \| Trachoma Neonatal conjunctivitis Neonatal pneumonia Nongonococcal urethritis (NGU) Urethritis Pelvic inflammatory disease Epididymitis Prostatitis Lymphogranuloma venereum (LGV) \| Erythromycin (adults) Doxycycline (infants and pregnant women) \| Erythromycin or silver nitrate in newborn's eyes Safe sex Abstinence
colspan=2\|Chlamydophila psittaci \| Inhalation of dust with secretions or feces from birds (e.g. parrots) \| Psittacosis, mainly atypical pneumonia \| Tetracycline Doxycycline Erythromycin \| -
rowspan=4\| Clostridium \| C. botulinum \| Spores from soil, persevere in canned food, smoked fish and honey \| Botulism: Mainly muscle weakness and paralysis \| Antitoxin Penicillin Hyperbaric oxygen Mechanical ventilation \| Proper food preservation techniques
C. difficile \| Gut flora, overgrowing when other flora is depleted \| Pseudomembranous colitis \| Discontinuing responsible antibiotic Vancomycin or metronidazole if severe \| Fecal bacteriotherapy
C. perfringens \| Spores in soil Vaginal flora and gut flora \| Anaerobic cellulitis Gas gangrene Acute food poisoning \| Gas gangrene: Debridement or amputation Hyperbaric medicine High doses of doxycycline or penicillin G and clindamycin Food poisoning: Supportive care is sufficient \| Appropriate food handling
C. tetani \| Spores in soil, skin penetration through wounds \| Tetanus: muscle spasms{{cite book\|last1=Atkinson\|first1=William\|title=Tetanus Epidemiology and Prevention of Vaccine-Preventable Diseases\|date=May 2012\|publisher=Public Health Foundation\|isbn=9780983263135\|pages=291–300\|edition=12\|url=https://www.cdc.gov/vaccines/pubs/pinkbook/tetanus.html\|access-date=12 February 2015\|url-status=live\|archive-url=https://web.archive.org/web/20150213010501/http://www.cdc.gov/vaccines/pubs/pinkbook/tetanus.html\|archive-date=13 February 2015}} \| Tetanus immune globulin Sedatives Muscle relaxants Mechanical ventilation Penicillin or metronidazole \| Tetanus vaccine (such as in the DPT vaccine)
colspan=2\| Corynebacterium diphtheriae \| respiratory droplets part of human flora \| Diphtheria: Fever, sore throat and neck swelling, potentially narrowing airways.{{cite journal \|date=20 January 2006 \|title=Diphtheria vaccine \|url=https://bojadla.edu.pl/b/wer8103.pdf \|journal=Wkly Epidemiol Rec \|volume=81 \|issue=3 \|pages=24–32 \|pmid=16671240 \|df=dmy-all}} \| Horse serum antitoxin Erythromycin Penicillin \| DPT vaccine
Ehrlichia \| E. canis E. chaffeensis \| Dog tick \| Ehrlichiosis: headache, muscle aches, and fatigue \| doxycycline rifampin
Enterococcus \| E. faecalis E. faecium \| Part of gut flora, opportunistic or entering through GI tract or urinary system wounds \| Bacterial endocarditis, biliary tract infections, urinary tract infections \| Ampicillin (combined with aminoglycoside in endocarditis) Vancomycin \| No vaccine Hand washing and other nosocomial prevention
rowspan=5\| Escherichia \| E. coli (generally) \| Gut flora, and in urinary tract Spreading extraintestinally or proliferating in the GI tract \| Diarrhea Urinary tract infections (UTI) Meningitis in infants Hospital-acquired pneumonia Hospital-acquired sepsis \|rowspan=5\| UTI: (resistance-tests are required first) Co-trimoxazole Fluoroquinolone, e.g. ciprofloxacin Meningitis: Cephalosporin (e.g. cefotaxime) and gentamicin combination Diarrhea: Antibiotics above shorten duration Electrolyte and fluid replacement \|rowspan=5\| (no vaccine or preventive drug) Cooking ground beef and pasteurizing milk against O157:H7 Hand washing and disinfection
Enterotoxigenic E. coli (ETEC) \| Fecal–oral through food and water Direct physical contact \| Traveller's diarrhea
Enteropathogenic E. coli \| Vertical, in utero or at birth \| Diarrhea in infants
Enteroinvasive E.coli (EIEC) \| Fecal–oral{{cite web\|url=http://www.phac-aspc.gc.ca/lab-bio/res/psds-ftss/escherichia-coli-eng.php\|title=ESCHERICHIA COLI\|publisher=Public Health Agency of Canada\|date=2012-04-30\|access-date=2015-06-02}} \| bloody diarrhea and fever
Enterohemorrhagic (EHEC), including E. coli O157:H7 \| Reservoir in cattle \| bloody diarrhea Hemolytic-uremic syndrome
colspan=2\| Francisella tularensis \| vector-borne by arthropods Infected wild or domestic animals, birds or house pets \| Tularemia: Fever, ulceration at entry site and/or lymphadenopathy.{{cite web\|url=https://www.cdc.gov/tularemia/signssymptoms/\|title=Signs & Symptoms\|website=Centers for Disease Control and Prevention\|date=13 December 2018}} Page last reviewed: October 26, 2015 Can cause severe pneumonia. \| Streptomycin Gentamicin \| Avoiding insect vectors Precautions when handling wild animals or animal products
colspan=2\| Haemophilus influenzae \| Droplet contact Human flora of e.g. upper respiratory tract \| Bacterial meningitis Upper respiratory tract infections Pneumonia, bronchitis Septic arthritis in infants \| Meningitis: (resistance-tests are required first) Third generation cephalosporin, e.g. cefotaxime or ceftriaxone Ampicillin and sulbactam combination \| Hib vaccine to infants Rifampin prophylactically
colspan=2\| Helicobacter pylori \| Colonizing stomach Unclear person-to-person transmission \| Peptic ulcer Chronic gastritis Risk factor for gastric carcinoma and gastric B-cell lymphoma \| Tetracycline, metronidazole and bismuth salt combination \| (No vaccine or preventive drug)
colspan=2\| Klebsiella pneumoniae \| Mouth, skin, and gut flora.{{cite book \| editor1-last = Ryan \|editor1-first= KJ \|editor2-last= Ray \|editor2-first= CG \| title = Sherris Medical Microbiology \| edition = 4th \| publisher = McGraw Hill \| year = 2004 \| isbn = 978-0-8385-8529-0 }} Pneumonia upon aspiration \| Klebsiella pneumonia, with significant lung necrosis and hemoptysis Hospital-acquired urinary tract infection and sepsis \| 3rd generation cephalosporin ciprofloxacin \| hand hygiene.{{cite web\|url=https://www.cdc.gov/HAI/organisms/klebsiella/klebsiella.html\|title=Klebsiella pneumoniae in Healthcare Settings\|date=19 February 2021\|publisher=Centers for Disease Control and Prevention}} Page last reviewed: November 24, 2010. Page last updated: August 27, 2012
colspan=2\|Legionella pneumophila \| Droplet contact, from e.g. cooling towers, humidifiers, air conditioners and water distribution systems \| Legionnaire's Disease Pontiac fever \| Macrolides, such as erythromycin Fluoroquinolones Rifampin \| (no vaccine or preventive drug) Heating water
colspan=2\| Leptospira species \| Food and water contaminated by urine from infected wild or domestic animals. Leptospira survives for weeks in fresh water and moist soil. \| Leptospirosis: Headaches, muscle pains, and fevers; possible jaundice, kidney failure, pulmonary hemorrhage, and meningitis.{{cite journal\|last=Slack\|first=A\|title=Leptospirosis.\|journal=Australian Family Physician\|date=Jul 2010\|volume=39\|issue=7\|pages=495–8\|pmid=20628664}}{{cite journal\|last=McBride\|first=AJ\|author2=Athanazio, DA \|author3=Reis, MG \|author4= Ko, AI \|title=Leptospirosis \|journal=Current Opinion in Infectious Diseases\|date=Oct 2005\|volume=18\|issue=5\|pages=376–86\|pmid=16148523 \|doi=10.1097/01.qco.0000178824.05715.2c\|s2cid=220576544}} \| Doxycycline for mild cases{{cite book\|last1=Hartskeerl\|first1=Rudy A.\|last2=Wagenaar\|first2=Jiri F.P.\|editor1-last=Kasper\|editor1-first=Dennis L.\|editor2-last=Fauci\|editor2-first=Anthony S.\|title=Harrison's Infectious Diseases\|date=2017\|publisher=McGraw Hill Education\|location=New York\|isbn=978-1-259-83597-1\|pages=672–678\|chapter=Leptospirosis}} Intravenous penicillin for severe cases \| Vaccine not widely used Doxycycline Prevention of exposure Rodent control
colspan=2\| Listeria monocytogenes \| Raw milk or cheese, ground meats, poultry Vertically to newborn or fetus \| Listeriosis: :Meningitis :Sepsis \| Ampicillin Co-trimoxazole \| (no vaccine) Proper food preparation and handling
rowspan=2\| Mycobacterium \| M. leprae \| Prolonged human-human contact, e.g. through exudates from skin lesions to abrasion of other person \| Leprosy (Hansen's disease): granulomas of the nerves, respiratory tract, skin, and eyes.{{cite web\|title=Leprosy Fact sheet N°101\|url=https://www.who.int/mediacentre/factsheets/fs101/en/\|work=World Health Organization\|date=January 2014\|url-status=live\|archive-url=https://web.archive.org/web/20131212084309/http://www.who.int/mediacentre/factsheets/fs101/en/\|archive-date=2013-12-12}} \| Tuberculoid form: Dapsone and rifampin Lepromatous form: Clofazimine \| BCG vaccine shows some effects
M. tuberculosis \| Droplet contact \| Tuberculosis: chronic cough with blood-containing sputum, fever, night sweats, and weight loss{{cite web\|title=Tuberculosis Fact sheet N°104\|url=https://www.who.int/mediacentre/factsheets/fs104/en/\|website=WHO\|access-date=11 February 2016\|date=October 2015\|url-status=live\|archive-url=https://web.archive.org/web/20120823143802/http://www.who.int/mediacentre/factsheets/fs104/en/\|archive-date=23 August 2012\|df=dmy-all}} \| (difficult, see Tuberculosis treatment for more details) Standard "short" course: First 2 months, combination: Isoniazid Rifampicin Pyrazinamide Ethambutol Further 4 months, combination: Isoniazid Rifampicin \| BCG vaccine Isoniazid
colspan=2\|Mycoplasma pneumoniae \| Human flora Respiratory droplets \| Mycoplasma pneumonia \| Doxycycline and erythromycin \|
rowspan=2\| Neisseria \|N. gonorrhoeae \| Sexually transmitted vertical in birth \| Gonorrhea :Urethritis (men) :Pelvic inflammatory disease (women) Ophthalmia neonatorum Septic arthritis \| Uncomplicated gonorrhea: Ceftriaxone Tetracycline, e.g. doxycycline if also chlamydia is suspected Spectinomycin for resistance or patient allergy to cephalosporin Ophthalmia neonatorum: Erythromycin + ceftriaxone \| (No vaccine) Safe sex Erythromycin into eyes of newborn at risk
N. meningitidis \| Droplet transmission \| Meningococcal disease including meningitis Sepsis, including Waterhouse-Friderichsen syndrome \| Penicillin G Ceftriaxone \| NmVac4-A/C/Y/W-135 vaccine Rifampin
colspan=2\| Pseudomonas aeruginosa \| Opportunistic; Infects damaged tissues or people with immunodeficiency. \| Pseudomonas infection: Pneumonia Urinary tract infection Corneal infection Endocarditis Osteomyelitis Burn wound infection Sepsis Malignant external otitis \| Anti-pseudomonal penicillins such as ticarcillin Aminoglycoside \| (no vaccine) Topical silver sulfadiazine for burn wounds
colspan=2\| Nocardia asteroides \| In soil \| Nocardiosis: Pneumonia, endocarditis, keratitis, neurological or lymphocutaneous infection \| TMP/SMX \|
colspan=2\| Rickettsia rickettsii \| Wood or dog tick \| Rocky mountain spotted fever \| Doxycycline Chloramphenicol \| (no preventive drug or approved vaccine) Vector control, such as clothing Prompt removal of attached ticks
rowspan=2\| Salmonella \| S typhi \| Fecal–oral route, through food or water \| Typhoid fever type salmonellosis (fever, abdominal pain, hepatosplenomegaly, rose spots) Chronic carrier state \| Ceftriaxone Fluoroquinolones, e.g. ciprofloxacin \| Ty21a and ViCPS vaccines Hygiene and food preparation
Other Salmonella species e.g. S. typhimurium \| Fecal–oral Food contaminated by fowl (e.g. uncooked eggs) or turtles \| Salmonellosis with gastroenteritis Paratyphoid fever Osteomyelitis in people with sickle cells Sepsis \| Fluid and electrolyte replacement for diarrhea Antibiotics (in neonates and immuno-compromised): :* Ciprofloxacin :* Ceftriaxone :* TMP/SMX :* Azithromycin \| (No vaccine or preventive drug) Proper sewage disposal Food preparation Good personal hygiene
Shigella \| S. sonnei S. dysenteriae \| Fecal–oral \| Shigellosis (bacillary dysentery) \| Fluid and electrolyte replacement Fluoroquinolone such as ciprofloxacin if severe \| Protection of water and food supplies Vaccines are in trial stage[http://www.pasteur.fr/ip/easysite/go/03b-00002u-06f/press/press-releases/2009/vaccine-against-shigellosis-bacillary-dysentery-a-promising-clinical-trial Institut Pasteur Press Office - Vaccine against shigellosis (bacillary dysentery):a promising clinical trial] {{webarchive\|url=https://web.archive.org/web/20090225214950/http://www.pasteur.fr/ip/easysite/go/03b-00002u-06f/press/press-releases/2009/vaccine-against-shigellosis-bacillary-dysentery-a-promising-clinical-trial \|date=2009-02-25 }} 15 January 2009. Retrieved on 27 February 2009
rowspan=3\|Staphylococcus \| aureus \| Human flora on mucosae in e.g. anterior nares, skin and vagina, entering through wound \| Coagulase-positive staphylococcal infections: Skin infections, including impetigo Acute infective endocarditis Septis Necrotizing pneumonia Meningitis Osteomyelitis Toxinoses Scalded skin syndrome Toxic shock syndrome Staphylococcal food poisoning \| Incision and drainage of localized lesions Nafcillin, oxacillin, methicillin Vancomycin for Methicillin-resistant (MRSA) \| (no vaccine or preventive drug) Barrier precautions, washing hands and fomite disinfection in hospitals
epidermidis \| Human flora in skin, anterior nares and mucous membranes \| Infections of implanted prostheses (e.g. heart valves and joints) and catheters \| Vancomycin \| None
saprophyticus \| Part of normal vaginal flora \| Cystitis in women \| TMP/SMX or norfloxacin{{cite book \|last= Levinson \|first= W. \|title=Review of Medical Microbiology and Immunology \|year=2010 \|edition=11th \|pages=94–9 }} \| None
rowspan=4\| Streptococcus \| agalactiae \| Human flora in vagina, urethral mucous membranes, rectum Vertically during childbirth Sexually \| Neonatal meningitis Neonatal sepsis Neonatal pneumonia Endometritis in postpartum women Opportunistic infections with sepsis and pneumonia \| Penicillin G Aminoglycoside in case of lethal infection \| None
pneumoniae \| Respiratory droplets Human flora in nasopharynx (spreading in immunocompromised) \| Acute bacterial pneumonia & meningitis in adults Otitis media and sinusitis in children Sepsis \| Penicillin G \| 23-serotype vaccine for adults (PPV) Heptavalent conjugated vaccine for children (PCV)
pyogenes \| Respiratory droplets Direct physical contact with impetigo lesions \| Streptococcal pharyngitis Sepsis Scarlet fever Rheumatic fever Impetigo and erysipelas Puerperal fever Necrotizing fasciitis Poststreptococcal glomerulonephritis \| Penicillin G or V Macrolide, e.g. clarithromycin or erythromycin in penicillin allergy Drainage and debridement for necrotizing fasciitis \| No vaccine Rapid antibiotic treatment helps prevent rheumatic fever
viridans \| Oral flora, penetration through abrasions \| Subacute bacterial endocarditis Dental cavities Abscesses of brain and liver \| Penicillin G \|
colspan=2\| Treponema pallidum subspecies pallidum \| Sexual Vertical (from mother to fetus) \| Syphilis: First a chancre, (a painless skin ulceration), then diffuse rash.{{cite web\|title=Syphilis - CDC Fact Sheet (Detailed)\|url=https://www.cdc.gov/std/syphilis/stdfact-syphilis-detailed.htm\|website=CDC\|access-date=3 February 2016\|date=November 2, 2015\|url-status=live\|archive-url=https://web.archive.org/web/20160206003059/http://www.cdc.gov/std/syphilis/stdfact-syphilis-detailed.htm\|archive-date=6 February 2016\|df=dmy-all}} Later: gummas (soft growths), neurological, or heart symptoms.{{cite journal \|vauthors=Kent ME, Romanelli F \|title=Reexamining syphilis: an update on epidemiology, clinical manifestations, and management \|journal=Annals of Pharmacotherapy \|volume=42 \|issue=2 \|pages=226–36 \|date=February 2008 \|pmid=18212261 \|doi=10.1345/aph.1K086 \|s2cid=23899851 }} Congenital syphilis \| Penicillin G Doxycycline if penicillin allergy \| Penicillin offered to recent sexual partners{{cite journal \|vauthors=Hook EW \|title=Syphilis \|journal=Lancet \|volume=389 \|issue=10078 \|pages=1550–1557 \|year=2017 \|pmid=27993382 \|doi=10.1016/S0140-6736(16)32411-4 \|s2cid=208793678 }} Antibiotics to pregnant women if risk of transmitting to child No vaccine available Safe sex
colspan=2\| Vibrio cholerae \| Fecal–oral route Contaminated water and raw seafood \| Cholera: Severe "rice water" diarrhea \| Fluid and electrolyte replacement Doxycycline \| Proper sanitation Adequate food preparation
colspan=2\| Yersinia pestis \| Fleas from animals{{cite journal \|vauthors=Zhou D, Han Y, Yang R \|title=Molecular and physiological insights into plague transmission, virulence and etiology \|journal=Microbes Infect. \|volume=8 \|issue=1 \|pages=273–84 \|year=2006 \|pmid=16182593 \|doi=10.1016/j.micinf.2005.06.006}} Ingestion of animal tissues Respiratory droplets \| Plague: Bubonic plague Pneumonic plague \| Streptomycin primarily{{cite journal \| author=Wagle PM. \| title=Recent advances in the treatment of bubonic plague \| journal=Indian J Med Sci \| year=1948 \| volume=2 \| pages=489–94 }}{{cite journal \| author=Meyer KF. \| title=Modern therapy of plague \| journal=JAMA \| year=1950 \| volume=144 \| pages=982–5 \| pmid = 14774219 \| issue=12 \| doi=10.1001/jama.1950.02920120006003}} Tetracyclin{{cite journal \| vauthors=Kilonzo BS, Makundi RH, Mbise TJ \| title= A decade of plague epidemiology and control in the Western Usambara mountains, north-east Tanzania \| journal=Acta Tropica \| year=1992 \| volume=50 \| pages=323–9 \| pmid = 1356303 \| doi = 10.1016/0001-706X(92)90067-8 \| issue=4}} Supportive therapy for shock \| Plague vaccine{{cite journal \|vauthors=Bubeck SS, Dube PH \|title=Yersinia pestis CO92ΔyopH Is a Potent Live, Attenuated Plague Vaccine \|journal=Clin. Vaccine Immunol. \|volume=14 \|issue=9 \|pages=1235–8 \|date=September 2007 \|pmid=17652523 \|pmc=2043315 \|doi=10.1128/CVI.00137-07 }} Minimize exposure to rodents and fleas \|

class="wikitable" style="font-size:0.9em;"

|+Species of human pathogenic bacteria

style="width: 14%" colspan=2| Species

!style="width: 25%"| Transmission

!style="width: 22%"| Diseases

!style="width: 15%"| Treatment

!style="width: 24%"| Prevention

colspan=2| Actinomyces israelii

| Oral flora

| Actinomycosis: painful abscesses and cysts MRSA in the mouth, lungs,{{cite journal|last=Brook|first=I|title=Actinomycosis: diagnosis and management.|journal=Southern Medical Journal|date=Oct 2008|volume=101|issue=10|pages=1019–23|pmid=18791528|doi=10.1097/SMJ.0b013e3181864c1f|s2cid=19554893}}{{cite journal | last=Mabeza | first=GF |author2= Macfarlane J | title=Pulmonary actinomycosis | journal=European Respiratory Journal | volume=21 | issue=3 | pages=545–551 | date=March 2003 | pmid=12662015 | doi=10.1183/09031936.03.00089103 | doi-access=free }} or gastrointestinal tract.{{cite book | author = Bowden GHW | title = Actinomycosis in: Baron's Medical Microbiology| editor = Baron S| display-editors = etal| edition = 4th | publisher = Univ of Texas Medical Branch | year = 1996 | id = [https://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mmed.section.1883 (via NCBI Bookshelf)] | isbn = 978-0-9631172-1-2 }}

| Prolonged penicillin G and drainage

colspan=2| Bacillus anthracis

Contact with cattle, sheep, goats and horses{{cite web |url=http://www.fao.org/ag/magazine/0112sp.htm |title=Anthrax in animals |date=2001 |publisher=Food and Agriculture Organization }}

Spores enter through inhalation or through abrasions

Anthrax: pulmonary, gastrointestinal and/or cutaneous symptoms.{{cite web|title=Bacteria Table|url=http://medschool.creighton.edu/fileadmin/user/medicine/MMI/Files/Bacteria_Table.pdf|publisher=Creighton University School of Medicine|access-date=2015-05-03|url-status=dead|archive-url=https://web.archive.org/web/20150501071840/http://medschool.creighton.edu/fileadmin/user/medicine/MMI/Files/Bacteria_Table.pdf|archive-date=2015-05-01}}

| In early infection:{{cite web|url=http://emergency.cdc.gov/agent/anthrax/faq/treatment.asp|title=CDC Anthrax Q & A: Treatment|access-date=4 April 2011|archive-url=https://web.archive.org/web/20110505191339/http://emergency.cdc.gov/agent/anthrax/faq/treatment.asp|archive-date=5 May 2011|url-status=dead}}

Penicillin

Doxycycline

Ciprofloxacin

Raxibacumab{{cite web |url=https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm332341.htm |archive-url=https://web.archive.org/web/20121217061133/http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm332341.htm |url-status=dead |archive-date=December 17, 2012 |title=FDA approves raxibacumab to treat inhalational anthrax|website=Food and Drug Administration|access-date=14 December 2012}}

Anthrax vaccine

Autoclaving of equipment

colspan=2| Bacteroides fragilis

| Gut flora

| Abscesses in gastrointestinal tract, pelvic cavity and lungs

| metronidazole

| Wound care{{cite web|title=Bacteroides Infection Follow-up|url=http://emedicine.medscape.com/article/233339-followup|publisher=Medscape|author=Itzhak Brook|date=Jan 28, 2014|access-date=2015-09-25}}

Aspiration prevention

colspan=2| Bordetella pertussis

Contact with respiratory droplets expelled by infected human hosts.

Whooping cough

Secondary bacterial pneumonia

|Macrolides such as erythromycin, before paroxysmal stage

Pertussis vaccine, such as in DPT vaccine

rowspan=2|Borrelia

|B. burgdorferi

B. garinii

B. afzelii

Ixodes hard ticks
Reservoir in mice, other small mammals, and birds{{cite journal |vauthors=Shapiro ED |title=Clinical practice. Lyme disease |journal=The New England Journal of Medicine |volume=370 |issue=18 |pages=1724–31 |year=2014 |pmid=24785207 |pmc=4487875 |doi=10.1056/NEJMcp1314325 }}

Lyme disease{{cite journal |vauthors=Sanchez JL |title=Clinical Manifestations and Treatment of Lyme Disease |journal=Clinics in Laboratory Medicine |volume=35 |issue=4 |pages=765–78 |year=2015 |pmid=26593256 |doi=10.1016/j.cll.2015.08.004 }}{{cite journal |vauthors=Halperin JJ |title=Nervous System Lyme Disease |journal=Clinics in Laboratory Medicine |volume=35 |issue=4 |pages=779–95 |year=2015 |pmid=26593257 |doi=10.1016/j.cll.2015.07.002 }}

Early localized: erythema migrans
Early disseminated: neuroborreliosis, Lyme carditis
Late: Lyme arthritis, Achrodermatitis chronica (B. afzelii only)

Doxycycline for adults, amoxicillin for children, ceftriaxone for neurological involvement

Wearing clothing that limits skin exposure to ticks.

Insect repellent.

Avoid areas where ticks are found.

B. recurrentis{{cite book|last1=Barbour|first1=Alan G.|editor1-last=Kasper|editor1-first=Dennis L.|editor2-last=Fauci|editor2-first=Anthony S.|title=Harrison's Infectious Diseases|date=2017|publisher=McGraw Hill Education|location=New York|isbn=978-1-259-83597-1|pages=678–687|edition=3rd|chapter=Relapsing Fever}}

and others

| Pediculus humanus corporis body louse (B. recurrentis only) and Ornithodoros soft ticks

| Relapsing fever

| Penicillin, tetracycline, doxycycline{{cite journal |vauthors=Cutler SJ |title=Relapsing Fever Borreliae: A Global Review |journal=Clinics in Laboratory Medicine |volume=35 |issue=4 |pages=847–65 |year=2015 |pmid=26593261 |doi=10.1016/j.cll.2015.07.001 }}

| Avoid areas where ticks are found

Better access to washing facilities

Reduce crowding

Pesticides

Brucella

|B. abortus

B. canis

B. melitensis

B. suis

Direct contact with infected animal

Oral, by ingestion of unpasteurized milk or milk products

Brucellosis: mainly fever, muscular pain and night sweats

doxycycline

streptomycin
or gentamicin

colspan=2|Campylobacter jejuni

Fecal–oral from animals (mammals and fowl)

Uncooked meat (especially poultry)

Contaminated water

Enteritis, bloody diarrhea
Guillain–Barré syndrome (muscle weakness)

Treat symptoms

Fluoroquinolone such as ciprofloxacin in severe cases

Good hygiene

Avoiding contaminated water

Pasteurizing milk and milk products

Cooking meat (especially poultry)

rowspan=2| Chlamydia

Respiratory droplets

| None

C. trachomatis

vaginal sex

oral sex

anal sex

Vertical from mother to newborn(ICN)

Direct or contaminated surfaces and flies (trachoma)

Trachoma

Neonatal conjunctivitis

Neonatal pneumonia

Nongonococcal urethritis (NGU)

Urethritis

Pelvic inflammatory disease

Epididymitis

Prostatitis

Lymphogranuloma venereum (LGV)

Erythromycin
(adults)

Doxycycline
(infants and pregnant women)

Erythromycin or silver nitrate in newborn's eyes

Safe sex

Abstinence

colspan=2|Chlamydophila psittaci

| Inhalation of dust with secretions or feces from birds (e.g. parrots)

| Psittacosis, mainly atypical pneumonia

Tetracycline

Doxycycline

Erythromycin

| -

rowspan=4| Clostridium

| C. botulinum

| Spores from soil, persevere in canned food, smoked fish and honey

Botulism: Mainly muscle weakness and paralysis

Antitoxin

Penicillin

Hyperbaric oxygen

Mechanical ventilation

Proper food preservation techniques

C. difficile

Gut flora, overgrowing when other flora is depleted

Pseudomembranous colitis

Discontinuing responsible antibiotic

Vancomycin or metronidazole if severe

| Fecal bacteriotherapy

C. perfringens

Spores in soil

Vaginal flora and gut flora

Anaerobic cellulitis

Gas gangrene

Acute food poisoning

| Gas gangrene:

Debridement or amputation

Hyperbaric medicine

High doses of doxycycline or penicillin G and clindamycin

Food poisoning:

Supportive care is sufficient

| Appropriate food handling

C. tetani

Spores in soil, skin penetration through wounds

Tetanus: muscle spasms{{cite book|last1=Atkinson|first1=William|title=Tetanus Epidemiology and Prevention of Vaccine-Preventable Diseases|date=May 2012|publisher=Public Health Foundation|isbn=9780983263135|pages=291–300|edition=12|url=https://www.cdc.gov/vaccines/pubs/pinkbook/tetanus.html|access-date=12 February 2015|url-status=live|archive-url=https://web.archive.org/web/20150213010501/http://www.cdc.gov/vaccines/pubs/pinkbook/tetanus.html|archive-date=13 February 2015}}

Tetanus immune globulin

Sedatives

Muscle relaxants

Mechanical ventilation

Penicillin or metronidazole

Tetanus vaccine (such as in the DPT vaccine)

colspan=2| Corynebacterium diphtheriae

respiratory droplets

part of human flora

Diphtheria: Fever, sore throat and neck swelling, potentially narrowing airways.{{cite journal |date=20 January 2006 |title=Diphtheria vaccine |url=https://bojadla.edu.pl/b/wer8103.pdf |journal=Wkly Epidemiol Rec |volume=81 |issue=3 |pages=24–32 |pmid=16671240 |df=dmy-all}}

Horse serum antitoxin

Erythromycin

Penicillin

DPT vaccine

Ehrlichia

| E. canis

E. chaffeensis

| Dog tick

| Ehrlichiosis: headache, muscle aches, and fatigue

Enterococcus

| E. faecalis

E. faecium

Part of gut flora, opportunistic or entering through GI tract or urinary system wounds

Bacterial endocarditis, biliary tract infections, urinary tract infections

Ampicillin (combined with aminoglycoside in endocarditis)

Vancomycin

No vaccine

Hand washing and other nosocomial prevention

rowspan=5| Escherichia

| E. coli (generally)

Gut flora, and in urinary tract
Spreading extraintestinally or proliferating in the GI tract

|rowspan=5| UTI:

(resistance-tests are required first)

Co-trimoxazole
Fluoroquinolone, e.g. ciprofloxacin

Meningitis:

Cephalosporin (e.g. cefotaxime) and gentamicin combination

Diarrhea:

Antibiotics above shorten duration
Electrolyte and fluid replacement

|rowspan=5| (no vaccine or preventive drug)

Cooking ground beef and pasteurizing milk against O157:H7
Hand washing and disinfection

Enterotoxigenic E. coli (ETEC)

Fecal–oral through food and water
Direct physical contact

Traveller's diarrhea

Enteropathogenic E. coli

Vertical, in utero or at birth

Diarrhea in infants

Enteroinvasive E.coli (EIEC)

Fecal–oral{{cite web|url=http://www.phac-aspc.gc.ca/lab-bio/res/psds-ftss/escherichia-coli-eng.php|title=ESCHERICHIA COLI|publisher=Public Health Agency of Canada|date=2012-04-30|access-date=2015-06-02}}

bloody diarrhea and fever

Enterohemorrhagic (EHEC), including E. coli O157:H7

Reservoir in cattle

colspan=2| Francisella tularensis

vector-borne by arthropods
Infected wild or domestic animals, birds or house pets

| Tularemia: Fever, ulceration at entry site and/or lymphadenopathy.{{cite web|url=https://www.cdc.gov/tularemia/signssymptoms/|title=Signs & Symptoms|website=Centers for Disease Control and Prevention|date=13 December 2018}} Page last reviewed: October 26, 2015 Can cause severe pneumonia.

Avoiding insect vectors
Precautions when handling wild animals or animal products

colspan=2| Haemophilus influenzae

Droplet contact
Human flora of e.g. upper respiratory tract

| Meningitis:

(resistance-tests are required first)

Third generation cephalosporin, e.g. cefotaxime or ceftriaxone
Ampicillin and sulbactam combination

Hib vaccine to infants
Rifampin prophylactically

colspan=2| Helicobacter pylori

Colonizing stomach
Unclear person-to-person transmission

Peptic ulcer
Chronic gastritis
Risk factor for gastric carcinoma and gastric B-cell lymphoma

Tetracycline, metronidazole and bismuth salt combination

| (No vaccine or preventive drug)

colspan=2| Klebsiella pneumoniae

Mouth, skin, and gut flora.{{cite book | editor1-last = Ryan |editor1-first= KJ |editor2-last= Ray |editor2-first= CG | title = Sherris Medical Microbiology | edition = 4th | publisher = McGraw Hill | year = 2004 | isbn = 978-0-8385-8529-0 }}
Pneumonia upon aspiration

Klebsiella pneumonia, with significant lung necrosis and hemoptysis
Hospital-acquired urinary tract infection and sepsis

hand hygiene.{{cite web|url=https://www.cdc.gov/HAI/organisms/klebsiella/klebsiella.html|title=Klebsiella pneumoniae in Healthcare Settings|date=19 February 2021|publisher=Centers for Disease Control and Prevention}} Page last reviewed: November 24, 2010. Page last updated: August 27, 2012

colspan=2|Legionella pneumophila

Droplet contact, from e.g. cooling towers, humidifiers, air conditioners and water distribution systems

| (no vaccine or preventive drug)

Heating water

colspan=2| Leptospira species

Food and water contaminated by urine from infected wild or domestic animals. Leptospira survives for weeks in fresh water and moist soil.

Leptospirosis: Headaches, muscle pains, and fevers; possible jaundice, kidney failure, pulmonary hemorrhage, and meningitis.{{cite journal|last=Slack|first=A|title=Leptospirosis.|journal=Australian Family Physician|date=Jul 2010|volume=39|issue=7|pages=495–8|pmid=20628664}}{{cite journal|last=McBride|first=AJ|author2=Athanazio, DA |author3=Reis, MG |author4= Ko, AI |title=Leptospirosis |journal=Current Opinion in Infectious Diseases|date=Oct 2005|volume=18|issue=5|pages=376–86|pmid=16148523 |doi=10.1097/01.qco.0000178824.05715.2c|s2cid=220576544}}

Doxycycline for mild cases{{cite book|last1=Hartskeerl|first1=Rudy A.|last2=Wagenaar|first2=Jiri F.P.|editor1-last=Kasper|editor1-first=Dennis L.|editor2-last=Fauci|editor2-first=Anthony S.|title=Harrison's Infectious Diseases|date=2017|publisher=McGraw Hill Education|location=New York|isbn=978-1-259-83597-1|pages=672–678|chapter=Leptospirosis}}
Intravenous penicillin for severe cases

| Vaccine not widely used

Doxycycline

Prevention of exposure

Rodent control

colspan=2| Listeria monocytogenes

Raw milk or cheese, ground meats, poultry
Vertically to newborn or fetus

Listeriosis:

:*Meningitis

:*Sepsis

| (no vaccine)

Proper food preparation and handling

rowspan=2| Mycobacterium

| M. leprae

Prolonged human-human contact, e.g. through exudates from skin lesions to abrasion of other person

Leprosy (Hansen's disease): granulomas of the nerves, respiratory tract, skin, and eyes.{{cite web|title=Leprosy Fact sheet N°101|url=https://www.who.int/mediacentre/factsheets/fs101/en/|work=World Health Organization|date=January 2014|url-status=live|archive-url=https://web.archive.org/web/20131212084309/http://www.who.int/mediacentre/factsheets/fs101/en/|archive-date=2013-12-12}}

| Tuberculoid form:

Dapsone and rifampin

Lepromatous form:

Clofazimine

BCG vaccine shows some effects

M. tuberculosis

Droplet contact

Tuberculosis: chronic cough with blood-containing sputum, fever, night sweats, and weight loss{{cite web|title=Tuberculosis Fact sheet N°104|url=https://www.who.int/mediacentre/factsheets/fs104/en/|website=WHO|access-date=11 February 2016|date=October 2015|url-status=live|archive-url=https://web.archive.org/web/20120823143802/http://www.who.int/mediacentre/factsheets/fs104/en/|archive-date=23 August 2012|df=dmy-all}}

(difficult, see Tuberculosis treatment for more details)

Standard "short" course:

First 2 months, combination:
Isoniazid
Rifampicin
Pyrazinamide
Ethambutol
Further 4 months, combination:
Isoniazid
Rifampicin

colspan=2|Mycoplasma pneumoniae

Human flora
Respiratory droplets

Mycoplasma pneumonia

Doxycycline and erythromycin

rowspan=2| Neisseria

|N. gonorrhoeae

Sexually transmitted
vertical in birth

Gonorrhea

:*Urethritis (men)

:*Pelvic inflammatory disease (women)

| Uncomplicated gonorrhea:

Ceftriaxone
Tetracycline, e.g. doxycycline if also chlamydia is suspected
Spectinomycin for resistance or patient allergy to cephalosporin

Ophthalmia neonatorum:

Erythromycin + ceftriaxone

| (No vaccine)

Safe sex
Erythromycin into eyes of newborn at risk

N. meningitidis

Droplet transmission

Meningococcal disease including meningitis
Sepsis, including Waterhouse-Friderichsen syndrome

NmVac4-A/C/Y/W-135 vaccine
Rifampin

colspan=2| Pseudomonas aeruginosa

| Opportunistic; Infects damaged tissues or people with immunodeficiency.

| Pseudomonas infection:

Anti-pseudomonal penicillins such as ticarcillin
Aminoglycoside

| (no vaccine)

Topical silver sulfadiazine for burn wounds

colspan=2| Nocardia asteroides

| In soil

| Nocardiosis: Pneumonia, endocarditis, keratitis, neurological or lymphocutaneous infection

| TMP/SMX

colspan=2| Rickettsia rickettsii

Wood or dog tick

Rocky mountain spotted fever

| (no preventive drug or approved vaccine)

Vector control, such as clothing
Prompt removal of attached ticks

rowspan=2| Salmonella

| S typhi

Fecal–oral route, through food or water

Typhoid fever type salmonellosis (fever, abdominal pain, hepatosplenomegaly, rose spots)
Chronic carrier state

Ceftriaxone
Fluoroquinolones, e.g. ciprofloxacin

Ty21a and ViCPS vaccines
Hygiene and food preparation

Other Salmonella species

e.g. S. typhimurium

Fecal–oral
Food contaminated by fowl (e.g. uncooked eggs) or turtles

Salmonellosis with gastroenteritis
Paratyphoid fever
Osteomyelitis in people with sickle cells
Sepsis

Fluid and electrolyte replacement for diarrhea
Antibiotics (in neonates and immuno-compromised):

:* Ciprofloxacin

:* Ceftriaxone

:* TMP/SMX

:* Azithromycin

| (No vaccine or preventive drug)

Proper sewage disposal
Food preparation
Good personal hygiene

Shigella

| S. sonnei

S. dysenteriae

Fecal–oral

Shigellosis (bacillary dysentery)

Fluid and electrolyte replacement
Fluoroquinolone such as ciprofloxacin if severe

Protection of water and food supplies
Vaccines are in trial stage[http://www.pasteur.fr/ip/easysite/go/03b-00002u-06f/press/press-releases/2009/vaccine-against-shigellosis-bacillary-dysentery-a-promising-clinical-trial Institut Pasteur Press Office - Vaccine against shigellosis (bacillary dysentery):a promising clinical trial] {{webarchive|url=https://web.archive.org/web/20090225214950/http://www.pasteur.fr/ip/easysite/go/03b-00002u-06f/press/press-releases/2009/vaccine-against-shigellosis-bacillary-dysentery-a-promising-clinical-trial |date=2009-02-25 }} 15 January 2009. Retrieved on 27 February 2009

rowspan=3|Staphylococcus

| aureus

Human flora on mucosae in e.g. anterior nares, skin and vagina, entering through wound

| Coagulase-positive staphylococcal infections:

Incision and drainage of localized lesions
Nafcillin, oxacillin, methicillin
Vancomycin for Methicillin-resistant (MRSA)

| (no vaccine or preventive drug)

Barrier precautions, washing hands and fomite disinfection in hospitals

epidermidis

| Human flora in skin, anterior nares and mucous membranes

Infections of implanted prostheses (e.g. heart valves and joints) and catheters

Vancomycin

| None

saprophyticus

| Part of normal vaginal flora

Cystitis in women

TMP/SMX or norfloxacin{{cite book |last= Levinson |first= W. |title=Review of Medical Microbiology and Immunology |year=2010 |edition=11th |pages=94–9 }}

| None

rowspan=4| Streptococcus

| agalactiae

| Human flora in vagina, urethral mucous membranes, rectum

Vertically during childbirth
Sexually

Neonatal meningitis
Neonatal sepsis
Neonatal pneumonia
Endometritis in postpartum women
Opportunistic infections with sepsis and pneumonia

Penicillin G
Aminoglycoside in case of lethal infection

| None

pneumoniae

Respiratory droplets
Human flora in nasopharynx (spreading in immunocompromised)

Acute bacterial pneumonia & meningitis in adults
Otitis media and sinusitis in children
Sepsis

Penicillin G

23-serotype vaccine for adults (PPV)
Heptavalent conjugated vaccine for children (PCV)

pyogenes

Respiratory droplets
Direct physical contact with impetigo lesions

Penicillin G or V
Macrolide, e.g. clarithromycin or erythromycin in penicillin allergy
Drainage and debridement for necrotizing fasciitis

| No vaccine

Rapid antibiotic treatment helps prevent rheumatic fever

viridans

| Oral flora, penetration through abrasions

Subacute bacterial endocarditis
Dental cavities
Abscesses of brain and liver

| Penicillin G

colspan=2| Treponema pallidum subspecies pallidum

Sexual
Vertical (from mother to fetus)

Syphilis: First a chancre, (a painless skin ulceration), then diffuse rash.{{cite web|title=Syphilis - CDC Fact Sheet (Detailed)|url=https://www.cdc.gov/std/syphilis/stdfact-syphilis-detailed.htm|website=CDC|access-date=3 February 2016|date=November 2, 2015|url-status=live|archive-url=https://web.archive.org/web/20160206003059/http://www.cdc.gov/std/syphilis/stdfact-syphilis-detailed.htm|archive-date=6 February 2016|df=dmy-all}} Later: gummas (soft growths), neurological, or heart symptoms.{{cite journal |vauthors=Kent ME, Romanelli F |title=Reexamining syphilis: an update on epidemiology, clinical manifestations, and management |journal=Annals of Pharmacotherapy |volume=42 |issue=2 |pages=226–36 |date=February 2008 |pmid=18212261 |doi=10.1345/aph.1K086 |s2cid=23899851 }}
Congenital syphilis

Penicillin G
Doxycycline if penicillin allergy

Penicillin offered to recent sexual partners{{cite journal |vauthors=Hook EW |title=Syphilis |journal=Lancet |volume=389 |issue=10078 |pages=1550–1557 |year=2017 |pmid=27993382 |doi=10.1016/S0140-6736(16)32411-4 |s2cid=208793678 }}
Antibiotics to pregnant women if risk of transmitting to child
No vaccine available
Safe sex

colspan=2| Vibrio cholerae

Fecal–oral route
Contaminated water and raw seafood

Cholera: Severe "rice water" diarrhea

Fluid and electrolyte replacement
Doxycycline

Proper sanitation
Adequate food preparation

colspan=2| Yersinia pestis

Fleas from animals{{cite journal |vauthors=Zhou D, Han Y, Yang R |title=Molecular and physiological insights into plague transmission, virulence and etiology |journal=Microbes Infect. |volume=8 |issue=1 |pages=273–84 |year=2006 |pmid=16182593 |doi=10.1016/j.micinf.2005.06.006}}
Ingestion of animal tissues
Respiratory droplets

| Plague:

Streptomycin primarily{{cite journal | author=Wagle PM. | title=Recent advances in the treatment of bubonic plague | journal=Indian J Med Sci | year=1948 | volume=2 | pages=489–94 }}{{cite journal | author=Meyer KF. | title=Modern therapy of plague | journal=JAMA | year=1950 | volume=144 | pages=982–5 | pmid = 14774219 | issue=12 | doi=10.1001/jama.1950.02920120006003}}
Tetracyclin{{cite journal | vauthors=Kilonzo BS, Makundi RH, Mbise TJ | title= A decade of plague epidemiology and control in the Western Usambara mountains, north-east Tanzania | journal=Acta Tropica | year=1992 | volume=50 | pages=323–9 | pmid = 1356303 | doi = 10.1016/0001-706X(92)90067-8 | issue=4}}
Supportive therapy for shock

Plague vaccine{{cite journal |vauthors=Bubeck SS, Dube PH |title=Yersinia pestis CO92ΔyopH Is a Potent Live, Attenuated Plague Vaccine |journal=Clin. Vaccine Immunol. |volume=14 |issue=9 |pages=1235–8 |date=September 2007 |pmid=17652523 |pmc=2043315 |doi=10.1128/CVI.00137-07 }}
Minimize exposure to rodents and fleas

Genetic transformation

Of the 59 species listed in the table with their clinical characteristics, 11 species (or 19%) are known to be capable of natural genetic transformation.Bernstein H, Bernstein C, Michod RE (2018). Sex in microbial pathogens. Infection, Genetics and Evolution volume 57, pages 8-25. https://doi.org/10.1016/j.meegid.2017.10.024 Natural transformation is a bacterial adaptation for transferring DNA from one cell to another. This process includes the uptake of exogenous DNA from a donor cell by a recipient cell and its incorporation into the recipient cell's genome by recombination. Transformation appears to be an adaptation for repairing damage in the recipient cell's DNA. Among pathogenic bacteria, transformation capability likely serves as an adaptation that facilitates survival and infectivity. The pathogenic bacteria able to carry out natural genetic transformation (of those listed in the table) are Campylobacter jejuni, Enterococcus faecalis, Haemophilus influenzae, Helicobacter pylori, Klebsiella pneumoniae, Legionella pneumophila, Neisseria gonorrhoeae, Neisseria meningitidis, Staphylococcus aureus, Streptococcus pneumoniae and Vibrio cholerae.{{citation needed|date=June 2021}}

Notes

{{Reflist|group="note"|

refs=

Relapsing fever can also be caused by the following Borrelia species: B. crocidurae, B. duttonii, B. hermsii, B. hispanica, B. miyamotoi, B. persica, B. turicatae and B. venezuelensis.
- {{cite book|last1=Barbour|first1=Alan G.|editor1-last=Kasper|editor1-first=Dennis L.|editor2-last=Fauci|editor2-first=Anthony S.|title=Harrison's Infectious Diseases|date=2017|publisher=McGraw Hill Education|location=New York|isbn=978-1-259-83597-1|pages=678–687|edition=3rd|chapter=Relapsing Fever}}

}}

References

External links

{{Medical resources

| DiseasesDB =

| ICD10 =

| ICD9 =

| ICDO =

| OMIM =

| MedlinePlus =

| eMedicineSubj =

| eMedicineTopic =

| MeshID = D001424

| GeneReviewsID =

| GeneReviewsName =

}}

[http://www.atsu.edu/faculty/chamberlain/Website/studio.htm Bacterial Pathogen Pronunciation] by Neal R. Chamberlain, Ph.D. at A.T. Still University
[http://patricbrc.org Pathogenic bacteria] genomes and related information at [http://patricbrc.org/ PATRIC], a Bioinformatics Resource Center funded by [https://www.niaid.nih.gov/ NIAID]

Category:Bacterial diseases