Equine Zoonoses

Question 1

common zoonoses in horses in the US

Answer 1

1. streptococcus equi zooepidemicus/equi
2. dermatophilosis
3. dermatophytosis
4. clostridioides difficile
5. Rhodococcus equi

Question 2

Foreign animal diseases

Answer 2

Hendra virus and Venezuelan equine encephalitis

Question 3

Streptococcus equi zooepidemicus

Answer 3

respiratory commensal in horses and can be an equine pathogen

Question 4

S. equi equi is known as __ and requires a __ level of biosecurity since its very __ to expose vets and owners causing bacteremia, myositis, endocarditis, glomerulonephritis, localized infections and meningitis in humans

Answer 4

strangles, higher, easy

Question 5

Rhodococcus is ubiquitous on horse farms worldwide in the __and spread by __ but is a __ risk for humans with normal immune function

Answer 5

soil, inhalation, low

Question 6

Clostridioides difficile

Answer 6

It causes diarrhea and GI inflammation varying morbidity and mortality in horses. While humans get it, the ubiquitous nature makes its source hard to pinpoint and its spread by fecal:oral transmission.

Question 7

Dermatophytosis is ____ and has a considerable zoonotic risk but can be managed with good care. Where do you typically see these horses?

Answer 7

ringworm, overcrowding and malnutrition

T. verrucosum and M. canis

Question 8

Dermatophilosis is also known as __, a disease of the skin caused by ____ while human infection are __

Answer 8

rain scald, deramtophilus congolensis, rare

Question 9

Salmonellosis is __ causing __ in horses and __ in foals by __ transmission. what signs does it cause in humans?

Answer 9

rare, enterocolitis, septicemia, fecal oral

GI signs, diarrhea, abd pain, vomitting, flu symptoms in immunocompromised humans

Question 10

Rabies is a __ virus that usually present as __ on exam and progresses to fatal. It’s one of the __ zoonoses of concern for humans exposure of what?

Answer 10

rhabdovirus, colic

urine, saliva, infected tissue

Question 11

Methicillin-resistant Staphylococcus aureus (MRSA)

Answer 11

associated with sx site infections, catheter site infections, cellulitis, pneumonis and septic arthritis in humans. It can be passed back and forth from horse to humans but infections in humans from horses is rare

Question 12

equine encephalitis viruses are spread by __ and __ vectors causing __ signs

Answer 12

bird and mosquito, neuro

Question 13

list the equine encephalitis viruses from highest mortality to lowest

Answer 13

1. EEE (75-90%)
2. VEE (40-90%)
3. WEE (20-50%)

Question 14

Eastern Equine Encephalitis has a human case fatality rate of __ with most survivors having __ deficits. what would be signs someone has EEE?

Answer 14

33%, neuro

flu like symptoms, nausea, vomiting, conjunctival congestion, encephalitis, seizures, coma, death

Question 15

West Nile Virus is a __ in wild birds transmitted to horses by mosquitoes as __ hosts. Can mosquitoes feeding on an infected horse transmit the virus to another horse or human?

Answer 15

flavivirus, incidental

no, they cannot transmit to another horse or human because the horse/human is a dead end host

Question 16

WNV in humans can be controlled by vaccination horses and mosquito control. If a human was infected, how would it present?

Answer 16

80% have no clinical signs while 20% have flu symptoms and 1:150 have neuro/fatal effects

Question 17

Vesicular stomatitis is a __ seen in horses and cattle only in the US. How is it transmitted?

Answer 17

Rhabdovirus/Vesiculovirus

It’s transmitted by contamination of transcutaneous or mucosal route OR arthropod transmission by flies

Question 18

Vesicular stomatitis has a __ incubation and typically recover in __ weeks and is __ in humans presenting as flue like symptoms

Answer 18

short (2-4d), 1-2, rare

Question 19

__ is the agent of anthrax and is a major zoonotic concern. Horses develop a __ form usually while humans develop a ___ form most commonly. How would you treat a human v a horse?

Answer 19

Bacillus Anthrax

systemic, cutaneous (ulcer with black eschar)

equids tx with penicillin
humans tx with penicillin and ciprofloxacin

Question 20

Hendra Virus is a __ that is maintained in the __ population. How are horses exposed?

Answer 20

henipavirus (paramyxovirus), bat

exposed by eating contaminated material such as bat urine

Question 21

how does hendra virus effect horses v humans?

Answer 21

horses will be in acute respiratory distress with possible neuro signs followed by death

vs

humans will have flu like symptoms that progress to pneumonitis, respiratory failure, renal failure, arterial thrombosis and cardiac arrest with case fatality rates of 60%

Question 22

t/f: humans acquire hendra virus from bats

Answer 22

F, human cases are acquired from horses (spread from bats to horses is accidental tho)

Question 23

Venezuelan Equine Encephalitis is a __ with an endemic strain in __ and __ while the epidemic strain is in __ and __

Answer 23

alphavirus, rodents and mosquitoes, horses and mosquitoes

Question 24

t/f: birds are part of the life cycle of VEE

Answer 24

F!!

Question 25

horses experience __ with VEE while humans have what symptoms?

Answer 25

encephalitis signs

rate of subclinical infection is high in humans while clinical disease will show signs of a fever, headache, nausea, v/d and encephalitis BUT the fatality rate is low