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| − | {{review}}
| + | <big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big> |
| − | | + | <big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big> |
| − | ===Overview===
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| − | *Causes tularaemia in wildlife, domestic animals and humans
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| − | *Wildlife reservoir of infection, including rabbits, rodents, galliform birds and deer
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| − | *Survives in the soil for up to 4 months
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| − | *Type A strains associated with terrestrial animal reservoirs; type B strains with water-borne infections and aquatic animals
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| − | *Ticks and deerfly act as vectors
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| − | *Fatal infection in humans, with ulers and lymphadenopathy; vaccine available
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| − | ===Characteristics===
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| − | *Gram negative rod with coccobacillary appearance
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| − | *Non-moltile, obligate aerobe
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| − | *Oxidase negative, weakly catalase positive
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| − | *Fastidious, requiring cysteine for growth on blood agar
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| − | *No growth on MacConkey
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| − | *Facultative intracellular pathogen
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| − | ===Pathogenesis and pathogenicity===
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| − | *High lipid content; virulent isolates produce capsules
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| − | *Highly virulent type A stains, ''F. tularensis'' subspecies ''tularensis'' in North America; less virulent type B strains, ''F. tularensis'' subspecies ''holarctica'' in Eurasia and North America
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| − | *Infection through skin abrasions or arthropod bites, inhalation or ingestion
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| − | *Organism survives and replicates in acidic environment of macrophages by inhibiting phagosome/lysosome fusion
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| − | *Acidic environment required for release of iron, required for growth, from tranferin
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| − | *Lymphadenitis and septicaemia
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| − | *Enlarged lymph nodes with pale necrotic foci
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| − | *Miliary lesions in [[Spleen - Anatomy & Physiology|spleen]] and liver
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| − | *Pulmonary consolidation; primary pulmonary lesions due to aerosol inhalation in dogs
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| − | ===Clinical infections===
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| − | *Fulminant disease in immunosuppressed
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| − | *Septicaemia with fever, depression, inappetence, stiffness
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| − | *Chronic granulomatous or subclinical infections
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| − | *Type A strains cause most infections in domestic animals; type B strains cause mild disease
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| − | *Rare outbreaks of tularaemia in sheep, horses and young pigs
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| − | *Adult pigs and cattle resistant
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| − | *Dogs and cats seroconvert without clinical signs
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| − | ===Diagnosis===
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| − | *Heavy tick infestation in severely infected animals in an endemic area indicate tularaemia
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| − | *Blood serology - high agglutinating antibody titres or rising antibody titre
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| − | *Scraping from ulcers, lymph node aspirates and biopsy material
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| − | *Post mortem
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| − | *Fluorescent antibody technique on tissues, exudates or culture
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| − | *Glucose-cysteine-blood agar used for culture
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| − | *Small, grey, mucoid colonies, surrounded by narrow zone of incomplete haemolysis, after 3-4 days incubation
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| − | *Immunofluorescence confirms presence in smears
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| − | *Slide agglutination test on cultures
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| − | *Biochemical tests to distinguish type A from type B strains
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| − | *PCR for detection in blood
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| − | *Isolation in embryonated eggs or lab animals
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| − | ===Treatment===
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| − | *Antibiotics including amikacin, streptomycin, fluoroquinolones
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| − | ===Control===
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| − | *Ectoparasite control
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| − | *Daily removal of ticks from dogs and cats
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| − | *Prevent dogs and cats hunting wildlife
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| − | [[Category:Bacteria miscellaneous]][[Category:Gram_negative_bacteria]][[Category:Coccobacilli]]
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| − | [[Category:Rods]]
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| − | [[Category:To_Do_-_Bacteria]]
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