Zoonotic Disease Flashcards
zoonosis
any disease or infection that is naturally transmissible from vertebrate animals to humans
what percent of existing disease in humans are zoonoses?
60%
what percent of new diseases in humans are zoonoses?
75%
why are there so many emerging zoonoses?
more direct contact with animals in pet and food animal environments
climate change has lead to habitat displacement and more encroachment on wildlife
what are the five stages of zoonotic disease?
- pathogen is present in animals but does not infect humans under normal conditions (feline distemper)
- pathogen can be transmitted from animals to humans but cannot be spread from human to human (Nipah)
- pathogen can be transmitted from animals to humans and can pass between humans. pathogen is not well adapted and will die put after a few cycles of transmission (Ebola)
- pathogen can be transmitted from animals to humans and can pass between humans. can adapt to living in humans for long period of time without going back to animals (cholera)
- pathogen that exclusively infects humans. pathogen may have co-evolved with humans recently and evolved into a specialized human pathogen (HIV)
what people are more susceptible to zoonoses?
infants
children
pregnant women
people undergoing chemo
immunocompromised
elderly
occupation with animals
what animals are more susceptible to zoonoses?
immunosuppressed
higher producing
reptiles
young animals
animals with diarrhea
exotic and wild animals
common zoonotic disease in dogs
rabies
ringworm
salmonellosis
leptospirosis
lyme
campylobacter
giardia
roundworms
hookworms
tapeworms
scabies
rabies stats
1 fatality causing zoonosis
more than 59000 deaths a year
death most common in children
rabies characteristics
bullet shaped neurotropic virus
transmitted by bats in NA, dogs in other countries
rabies symptoms
aggressiveness, hallucinations, fever, nausea, foaming at the mouth, fear of water
leptospirosis
has been found in almost all species of mammals
found in soil and water
prevalent in developed and developing countries
human infections are most commonly caused by contaminated water sources
leptospirosis symptoms
liver or kidney disease
fever, lack of energy, lack of appetite, red eyes, vomiting, jaundice, frequent urination, abdominal pain
leptospirosis clinical presentation
biphasic
septicemic phase lasts about a week and is followed by immune phase which is characterized by antibody production and excretion of leptospirosis in the urine
campylobateriosis
affects cattle, sheep, goats
transmitted to humans by raw milk, undercooked meat, cross contaminated food, etc and direct contact with animals or feces
campylobateriosis disease in animals
asymptomatic in most species
gastroenteritis (pigs), diarrhea (cattle, sheep, goats), mucoid, blood flecked diarrhea in chickens
abortion in cattle sheep and goats
chlamydiosis
caused by chlamydia abortus
affects sheep and goats
worlds leading cause of ovine enzootic abortion
spread by aerosols and reproductive fluids
listeria
affects cattle, sheep, goats
associated with contaminated feed (silage) and direct contact with reproductive tissues
listeria symptoms
abortion in cattle and sheep, dyspnea and meningitis with death in 12 hrs in calves, ataxia and circling in ruminants, silage eye or keratoconjuctivitis in ruminants
Q fever
cattle, sheep, and goats are reservoirs
Q fever modes of transmission
reproductive tissues, hides, wool
aerosols, raw milk/dairy
ticks and other vectors
Q fever reproductive consequences
abortion in ruminants and horses
stillbirth, weak offspring, and purulent cotyledons in goats
salmonella
affects cattle, pigs, horses
transmitted through raw milk, raw/undercooked meat, eggs, contaminated produce and water
direct: feces and animals
salmonella clinical signs
severe enteritis with or without blood, young most affected
abortion and decreased milk in cattle
septicemia and pneumonia in all young animals
staphylococcosis (staph a)
affects cattle
transmission from skin (teat), wounds, feces, contaminated food, equipment (fomites), aerosols
staphylococcosis clinical signs
wound infections, accesses, bubble foot and comb necrosis in poultry
mastitis and metritis in cattle, sheep, and swine
septicemia in chickens
streptococcosis
possible in cattle, sheep, and goats
transmitted through direct contact with infected animals, tissues, fluids, and skin wounds or ingestion of raw dairy
streptococcosis clinical signs
reproductive: mastitis, metritis, abortion
respiratory: purulent lung lesions and pneumonia
musculoskeletal: polyarthritis
neurologic: meningitis, ataxia, death (piglets)
systemic: septicemia in pigs and foals
contagious ecthyma (orf)
paradox virus affects sheep and goats
transmitted through skin lesions, scabs, animal vaccine
contagious ecthyma signs
asymptomatic in adults
causes pustules, vesicles; scabs on mouth, muzzle, eyelids, teats, etc., in young sheep
pseudocowpox
transmitted through direct contact with teat and udder lesions
