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A pathogen is an organism that bears ("gen") suffering ("pathos") upon another organism.

A vector, in pathology, is an organism that carries pathogens from one organism to another (examples: rats, mosquitoes, ticks).


Pathogens and vectors

 

A pathogen is an organism that bears ("gen") suffering ("pathos") upon another organism.

A vector, in pathology, is an organism that carries pathogens from one organism to another (examples: rats, mosquitoes, ticks).

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Lactobacillales

cellular organisms - Bacteria - Firmicutes - Bacilli - Lactobacillales -


Streptococcaceae - Streptococcus - Streptococcus pneumoniae

Most common pathogen of community-acquired pneumonia; the nasopharynx of children is an important global ecological reservoir of drug-resistant pneumococcus (DRP) and may also play a critical role as the favoured anatomical site for the evolution of DRP. CDC Notifiable Agent; Globally Important Human Pathogen Colonizes the mucosal surfaces of the host nasopharynx and upper airway. Can spread from the upper respiratory tract to the sterile regions of the lower respiratory tract, which leads to pneumonia; causes meningitis, otitis media, and sinusitis. Kadioglu A et al. (Nat Rev Microbiol. 2008);


Lynch JP 3rd et al. (Semin Respir Crit Care Med. 2009);


De Lencastre H et al. (J Antimicrob Chemother. 2002)

Streptococcaceae - Streptococcus - Streptococcus pyogenes

Common pathogen of hospital- and community-acquired infections; transmitted through contact with symptomatic and asymptomatic carriers. Medically important human pathogen; CDC Notifiable Agent Causes severe soft tissue infections; bacteremia; meningitis; toxic shock syndrome, etc. "group A streptococcus";


"Streptococcus pyogenes"

Plant pathogens

Fungi:

Gibberella moniliformis (fusarium)

Magnaporthe grisea (rice blast)

Phytophthora infestans (potato blight)

Ustilago maydis (corn smut)

Dog pathogens

Worms:

Ancylostoma caninum (hookworm)

Dirofilaria immitis (heartworm)

Viruses:

Canine Distemper Virus (CDV)

Fish pathogens

Microorganisms:

Ichthyophthirius multifiliis (ich, ick)

Pfiesteria piscicida (cell from hell)

Crustaceans:

Argulus sp. (fish louse)

Bee pathogens

Mites:

Varroa destructor (varroosis)

Clostridiales

cellular organisms - Bacteria - Firmicutes - Clostridia - Clostridiales -


Transmission Importance Disease description Selected literature

Clostridiaceae - Clostridium - Clostridium botulinum

Associated with food; historically, with sausages (Latin word for sausage = "botulus"); can temporarily colonize the intestinal tract of infants who ingested bacteria. Toxin can enter the body via inhalation, ingestion or injection. Medically important human pathogen; CDC Notifiable Agent; Validated Biocrime Agent; NIAID Category A Priority Pathogen; USDA High Consequences Animal Pathogen; HHS Select Pathogen Has 4 naturally occurring syndromes: foodborne, wound, infant botulism, and adult intestinal toxemia. All of these produce symmetrical cranial nerve palsies followed by descending, symmetric flaccid paralysis of voluntary muscles, which may progress to respiratory compromise and death. Fenicia L et al. (Ann Ist Super Sanita. 2009);


Brook I. (Rev Neurol Dis. 2006);


"clostridium botulinum"


"botulism"

Clostridiaceae - Clostridium - Clostridium difficile

A major cause of antibiotic-associated diarrhea within the hospital setting; risk factors include fluoroquinolone exposure and gastric acid suppression; can be commonly found in food animals and food but whether ingestion of contaminated food can result in colonization or infection remains unclear. Emergent Infectious Agent; Medically Important Human Pathogen Violent infectious diarrhea and fulminant colitis; may cause death. Hookman P et al. (World J Gastroenterol. 2009);


Weese JS. (Clin Microbiol Infect. 2010 );


"clostridium difficile"

Clostridiaceae - Clostridium - Clostridium perfringens

A common cause of food-borne illness due to an ability to form heat-resistant spores that survive normal cooking/heating temperatures, a rapid growth rate in warm food, and the production of enterotoxin (CPE) in the human gut. Emergent Infectious Agent; Principal Foofborne Pathogen; Medically Important Human Pathogen; Validated Biological Weapon; USDA High Consequences Animal Pathogen Causes food poisoning accompanied with acute gastroenteritis and has been reported in association with necrotizing enteritis. Brynestad S et al. (Int J Food Microbiol. 2002 );


Meer RR et al. (Rev Environ Contam Toxicol. 1997);


"Clostridium perfringens"

Clostridiaceae - Clostridium - Clostridium tetani

Natural habitat is soil, dust, and intestinal tracts of various animals. Infection occurs via bacterial contamination at a laceration or break in the skin. Can also occur as a complication of burns, umbilical stumps (tetanus neonatorum) and surgical-site infection. CDC Notifiable Agent; Globally Important Human Pathogen; Validated Biocrime Agent Neuromuscular dysfunction, caused by tetanal exotoxin (tetanospasmin), which starts with tonic spasms of the skeletal muscles and is followed by paroxysmal contractions. The muscle stiffness initially involves the jaw (lockjaw) and neck and later becomes generalized. Brook I. (Expert Rev Anti Infect Ther. 2008);


"Clostridium tetani"

Spirochaetales

cellular organisms - Bacteria - Spirochaetes - Spirochaetes (class) - Spirochaetales -


Transmission Importance Disease description Selected literature

Spirochaetaceae - Borrelia - Borrelia burgdorferi

Tick-borne; circulates in endemic areas between Ixodes sp. ticks and a large number of vertebrate hosts upon which ticks feed. Ixodes scapularis, black-legged tick, deer tick - vector of Lyme disease - facts and life cycle at MetaPathogen High Potential For Bioengeneering; Emergent Infectious Agent; CDC Notifiable Agent; Medically Important Human Pathogen Lyme disease usually starts with erythema migrans; later infection becomes systemic; up to 5% of patients develop cardiac involvement; in about 10% to 15% of patients, the nervous system becomes symptomatically involved. Borrelia burgdorferi, Lyme disease spirochete taxonomy, facts, pathogenicity, bibliography at MetaPathogen

Spirochaetaceae - Treponema - Treponema pallidum

Transmitted through sexual intercourse or through skin-to-skin contact, epidemiology highly depends on subspecies. CDC Notifiable Agent; Globally Important Human Pathogen Subspecies cause syphilis, yaws, bejel, and pinta. Treponema pallidum, sperochete causative agent of syphilis: taxonomy, history, biology at MetaPathogen

Chlamydiales

cellular organisms - Bacteria - Chlamydiae - Chlamydiae/Verrucomicrobia group - Chlamydiae - Chlamydiae (class) - Chlamydiales -


Transmission Importance Disease description Selected literature

Chlamydiaceae - Chlamydia - Chlamydia trachomatis

The most common sexually transmitted infection; also transmitted from mother to child. Emergent Infectious Agent; CDC Notifiable Agent; Globally Important Human Pathogen Causes genital tract infections in men, women, and children. Even asymptomatic infection may lead to severe reproductive complications in women such as infertility, tubal pregnancy, and cancer. Exposed infants often develop conjunctivitis, pneumonia, or both in the first few months of life. Lyons JM et al. (Drugs Today (Barc). 2009);


Steben M. (J Obstet Gynaecol Can. 2004);


"Chlamydia trachomatis"

Chlamydiaceae - Chlamydophila - Chlamydophila psittaci

Transmission usually originates from close contact with infected birds, most frequently in the context of the poultry industry, and from contact with Psittaciformes (cockatoos, parrots, parakeets and lories). Zoonotic Agent; Emergent Infectious Agent; CDC Notifiable Agent; Important Animal Pathogen; Medically Important Human Pathogen; Potential Biological Weapon Causes pneumonia, may cause respiratory failure and death. Beeckman DS et al. (Clin Microbiol Infect. 2009);


"Chlamydophila psittaci"

Actinomycetales

cellular organisms - Bacteria - Actinobacteria - Actinobacteria (class) - Actinobacteridae - Actinomycetales -


Transmission Importance Disease description Selected literature

Corynebacterineae - Corynebacteriaceae - Corynebacterium - Corynebacterium diphtheriae

Transmitted by close contact through droplets or nasopharyngeal secretions. Emergent Infectious Agent; CDC Notifiable Agent; Validated Biocrime Agent Nasopharyngitis, tonsillitis or laryngitis plus a pseudomembrane; may lead to endocarditis. Toxicogenic strains may cause airway obstruction, swelling of the neck, petechial haemorrhages, circulatory collapse, acute renal failure, myocarditis, motor paralysis, and death. Mokrousov I. (Mokrousov I.);


Wilson AP. (J Antimicrob Chemother. 1995);


"Corynebacterium diphtheriae"

Corynebacterineae - Mycobacteriaceae - Mycobacterium - Mycobacterium tuberculosis

Airborne; transmitted by close contact through droplets or nasopharyngeal secretions. Patients with pulmonary TB whose sputum is smear-positive for M. tuberculosis form the main source of infection in communities. Emergent Infectious Agent; CDC Notifiable Agent; Validated Biocrime Agent; Globally Important Human Pathogen; NIAID Category C Priority Pathogen About 20% of those infected actually develop tuberculosis (TB). Histologically, tuberculosis displays exudative inflammation in lungs, proliferative inflammation and productive inflammation (granulomatous lesions with necrotic centers are formed). Comas I, Gagneux S. (PLoS Pathog. 2009);


API Consensus Expert Committee. (J Assoc Physicians India. 2006);


"Mycobacterium tuberculosis";


Corynebacterineae - Mycobacteriaceae - Mycobacterium - Mycobacterium avium

Some evidence suggests that humans may become infected via contaminated milk. Zoonotic Agent; Emergent Infectious Agent; Important Animal Pathogen; Medically Important Human Pathogen Causes Johne's disease, a chronic enteritis in ruminants. A growing body of evidence suggests that human infection may be causing some, and possibly all, cases of Crohn's disease. Pierce ES. (PLoS Pathog. 2009);


Biet F. (Vet Res. 2005);


"Mycobacterium avium"