Zoonotic infections Flashcards
What is a zoonotic infection?
An infection of nonhuman animals transmitted to humans
How is Francisella tularensis transmitted?
Rabbits, ticks, deer flies
Dirt or plant material (pneumonia)
Bioterrorism agent aerosol
What is the most immportant Enterohemorrhagic E. coli (EHEC) infection in humans?
Serotype O157
Sporadic outbreaks
What are the clinical manifestations of EHEC?
Mild diarrhea
Hemorrhagic colitis (HC) - destruction of mucosa
Hemolytic-uremic syndrome (HUS) - acute renal failure, anemia, thrombocytopenia, neurologic complications
Where is EHEC found?
In the normal commensal in intestinal tract of cows
How does a EHEC infection occur?
When cattle feces are ingested
Unpasteurized milk or juice, hamburger, uncooked veggies
What is the most common cause of food-associated diarrhea (except in US and UK where it’s second place)?
Salmonella enterica
What family is Salmonella part of?
Enterobacteriacea
Where is Salmonella normally found?
Normal GI tract bacteria for poultry and other animals
How is Salmonella transmitted?
Contaminated food like poultry and dairy
How can Salmonella be spread?
Person-to-person with possible secondary spread
What is another major cause of diarrhea?
Campylobacter (pylori most common)
What is the reservoir for campylobactor?
Cattle, sheep, pigs, rodents, poultry and other birds
How is an infection of campylobactor acquired?
Consumption of contaminated food
Person-to-person but fecal-to-oral rare
What are the characteristics of Pasteurella sp?
P. multocida, P. canis
Gram neg coccobacilli
Isolated from dog and cat bites (part of normal flora)
What does Pasteurella cause and what are the complications?
Cellulitis and lymphadenitis
Abscess formation, tenosynovitis, osetomyelitis, septic arthritis
What causes cat scratch disease?
Bartonella henselae
What is Bartonella henselae characterized by?
Regional lymphadenitis after papule at the sire of scratch
Can become serious systemic disease
What are the characteristics of Streptobacillus moniliformis?
Rat-bite fever
Aerobic, gram neg, high pleomorphic
What is the source of Stretobacillus moniliformis?
Normal inhabitant in the oropharynx of rodents
What are the clinical manifestations for Streptobacillus moniliformis?
Relapsing feve (40C), shaking chills, myalgia, asymmetric polyarthritis, N&V, erythematous papulovesicular rash around bite
What are the characteristics of Rabiesvirus?
ssRNA (-) virus, nonsegmented genome, helical capsid, enveloped, bullet shaped
Virulence factors for rabies.
Virus-induced aggressive behavior in animals to spread
How is rabies transmitted?
Reservoir: wild animals
Vector: wild animals and unvax cats and dogs
What is the source of the rabies virus?
Major: saliva in bite of rabid animal
Minor: aerosols in bat caves with rabid bats
What is the pathogenic agent of monkeypox?
Orthopoxvirus: dsDNA
When did moneypox first emerge?
1970 in Congo
Skinning and handling animals
Re-emerged in 96-97
What is the main action of Hantavirus pulmonary syndrome?
Hemorrhagic fever with renal syndrome
Results from inhalation of rodent urine or feces
If infected, respiratory failure 20-50%
What are the reservoirs for hantavirus?
Deer mouse, white footed mouse, rice rat, cotton rat
What are prions?
Proteinaceous infection particles
What is the disease associated with prions?
Neurodegenerative: dementia, insomnia, paraplegia
CNS lesions
Long incubation
Fatal outcome
