Cross Species - Top 30 Zoonotic Diseases Part 6 Flashcards
what is the classic case presentation of toxoplasmosis in felids?
typically no clinical signs
if signs - acute fever, dyspnea, & encephalitis
what is the classic case presentation of toxoplasmosis in non-felid veterinary cases?
abortions, fever, depression, lethargy, & neuro signs
what is the classic case presentation of toxoplasmosis in pregnant women?
abortions & fetal abnormalities
what is the classic case presentation of toxoplasmosis in immunocompromised people?
fever, dyspnea, & multi-organ involvement
what is the etiology of toxoplasmosis? what is the definitive host? the intermediate host?
toxoplasma gondii - obligate intracellular protozoan
definitive host - felids, shed oocysts in feces that infect intermediate hosts
intermediate hosts - most mammals or marsupials with oocysts forming tachyzoites, bradyzoites, or cysts in tissues
how do humans get toxoplasmosis?
fecal oral route
how is toxoplasmosis infection in humans prevented?
avoid direct contact with cat feces - don’t clean the litter box if pregnant & wearing gloves when gardening
T/F: with toxoplasmosis, there is a worldwide distribution, & a suggested association between schizophrenia/epilepsy in people but evidence is lacking
true
what is the classic case presentation of leishmaniasis in dogs?
exfoliative dermatitis (ulcers, nodules), epistaxis, weight loss, exercise intolerance, lethargy, ocular lesions (uveitis, keratitis, blepharitis, conjunctivitis), lymphadenopathy, splenomegaly, anemia, hyperproteinemia (hyperglobulinemia & hypoalbuminemia), & proteinuria
what is the classic case presentation of cutaneous leishmaniasis in humans?
papules/nodules, raised ulcers, & regional lymphadenopathy
what is the classic case presentation of visceral leishmaniasis in humans?
also called kala-azar
fever, weight loss, hepatosplenomegaly
cbc - anemia, thrombocytopenia, & leukopenia
what is the etiology of leishmaniasis? what is the life cycle?
leishmania infantum - protozoan with a diphasic life cycle
sandfly vector - extracellular promastigote
dogs - intracellular amastigote
what are the main reservoir hosts of leishmaniasis?
in north america, dogs are main reservoir host
wood rats are also possible hosts
T/F: leishmaniasis is not directly transmissible between infected animals & humans
true
what is the zoonotic risk of leishmaniasis for humans?
usually transmitted through sandfly vector but other arthropods can act as vectors
rarely transmitted among humans via blood transfusions
how long is the incubation period of leishmaniasis?
weeks to months
where is new world leishmaniasis most commonly seen?
used to be most common in central & south america but becoming more prevalent in north america
T/F: leishmaniasis is most commonly seen in foxhounds in north america & vertical transmission is suspected
true
why is leishmaniasis a difficult disease?
difficult to treat in humans & animals & relapses are common
what is the classic case presentation of ehrlichiosis in dogs & cats?
fever, lameness, petechiation due to thrombocytopenia
what is the classic case presentation of anaplasmosis in ruminants?
animals under 1 year old - usually subclinical
older animals - rapid loss of conditioning, decreased milk production, inappetence, anemia, & possible sudden death
what is the classic case presentation of ehrlichiosis/anaplasmosis in humans?
fever, headache, myalgia, & multi-organ failure
what is the etiology of anaplasmosis? what diseases does it cause?
anaplasma phagocytophilum
human granulocytic anaplasmosis, equine granulocytic anaplasmosis, canine granulocytic anaplasmosis, & tick-borne fever in ruminants only seen in the eastern hemisphere
anaplasma platys - canine infectious cyclic thrombocytopenia
what is the etiology of ehrlichiosis? what diseases does it cause?
ehrlichia chaffeensis - human ehrlichiosis & canine monocytic ehrlichiosis
ehrlichia ewingii - canine granulocytic ehrlichiosis
how do humans get anaplasmosis & ehrlichiosis?
tick transmission
a. phagocytophilum - black legged tick (ixodes scapularis) & western black legged tick (ixodes pacificus)
a. platys - brown dog tick (rhipicephalus sanguineus)
ehrlichia species - lone-star tick (amblyomma americanum)
T/F: ehrlichiosis & anaplasmosis are not directly transmissible between infected animals & humans
true
what ehrlichiosis is not considered to be zoonotic?
ehrlichia canis - canine ehrlichiosis
T/F: ehrlichiosis & anaplasmosis can both be transmitted by blood transfusions
true
what is the classic case of borreliosis/lyme disease in dogs?
poorly characterized - renal disease, arthritis, cardiac dysfunction, & neuro signs
what is the classic case of borreliosis/lyme disease in horses?
poorly characterized - low grade fever, intermittent/shifting leg lameness, myalgia, cardiac arrhythmias, & neuro signs
what is the classic case of borreliosis/lyme disease in humans?
erythema migrans - target pattern or bull’s eye rash
flu-like illness, arthritis, facial nerve palsy, cardiac abnormalities
what is the etiology of borreliosis/lyme disease?
borrelia burgdorferi - motile spirochete bacterium
what is the life cycle of borreliosis/lyme disease?
life cycle between tick vectors & wild animal reservoir hosts
tick vectors - i. scapularis & i. pacificus
hosts for ticks - odocoileus virginianus (white tail deer)
reservoir hosts - small mammals, birds, & reptiles (especially white footed mouth)
what are the zoonotic risks of borreliosis/lyme disease?
tick bite transmissions
T/F: borreliosis/lyme disease is not directly transmitted between animals & humans
true
ticks infected with borrelia burgdorferi are commonly co-infected with what other diseases?
anaplasma spp and/or babesia spp
any or all may be transmitted to a single human
what diseases are involved in causing equine arboviral encephalomyelitis?
west nile virus, EEE, WEE, VEE
what is the classic case presentation of west nile virus in horses?
ataxia, weakness, fever, face/neck muscle tremors, colic, & hyperesthesia
what is the classic case presentation of eastern/western/venezuelan encephalomyelitis in horses?
fever, neuro signs (spinal cord & forebrain), & rapid progression
what is the classic case presentation of west nile virus in birds?
asymptomatic - anorexia, ruffled feathers, & neuro signs
what is the classic case presentation of west nile virus in humans?
fever, malaise, headache, body aches, skin rash, & may see neuroinvasive disease
what is the classic case presentation of EEE/WEE/VEE in humans?
fever, headache, & neuro signs
what is the etiology of west nile virus?
flavivirus - transmitted by culex spp mosquitoes
what is the main reservoir host of west nile virus? dead end host?
main - wild birds
dead end - horses
what is the etiology of EEE/WEE/VEE?
alphaviruses transmitted by several mosquito types
what are the main reservoir hosts of EEE/WEE/VEE? amplifiers/dead end host?
reservoir hosts - birds, small mammals, & reptiles
amplifiers - horses are important amplifiers for epidemic VEE
dead-end hosts for EEE/WEE - horses
what is the zoonotic risk of west nile virus & equine arbovirus encephalitis? what precautions can be taken?
spread by mosquito bites
west nile can also be shed in the oral/cloacal secretions of infected birds (corvids, gulls, raptors, domesticated chickens & turkeys)
precautions - prevent mosquito bites & use PPE when handling infected animals or in a labratory
T/F: west nile virus is a reportable disease with a worldwide distribution
true
T/F: only 1 in 5 people infected with west nile virus develop signs and 1 in 150 of these will develop serious illness
true
when was the last time VEE was reported in the US?
1971
T/F: the reported cases of WEE in humans & horses have dramatically decreased but the virulence of circulating viruses has not decreased
true
how do equine EEE cases act as an index for human cases?
equine cases generally precede human disease by 2 weeks - horses are not directly infecting humans
