Zoonotic Equine Viruses

Question 1

Is a commensal and opportunistic organism of equine upper respiratory and lower genital tracts. Can cause meningitis in humans.

Answer 1

Strep equi ss zooepidemicus

Question 2

Is an equine pathogen that causes chronic suppurative bronchopneumonia in foals.

Answer 2

Strep equi ss equi (Strangles)

Question 3

Is ubiquitous in the environment and GIT of asymptomatic animals. Causes GI issues w/ high morbidity, moderate mortality. Recent emergence in humans.

Answer 3

Clostridioides difficile

Question 4

Is seen in overcrowding and malnourished horses, and is spread via direct contact. Considerable zoonotic risk.

Answer 4

Dermatophytosis (Ringworm)

Question 5

Is an infectious, contagious derm disease of horses associated with persistent wetting or damage to skin. Rare human cases, but causes pustules that can rupture into crater-like cavities.

Answer 5

Dermatophilosis (Rain Scald) - Dermatophilus congolensis (an aerobic actinomycete)

normal inhabitant of the skin of horses but with persistent wetting and/or damage to the skin, infection occurs

Question 6

Spread via contaminated feed, water or environment by active shedders in their feces. Causes severe enterocolitis in adults, and septicemia in foals. In humans, causes GI signs, flu-like symptoms, and also systemic infections in immunocompromised individuals.

Answer 6

Salmonellosis - Salmonella enterica

Question 7

Is the primary focus of hospitals’ biosecurity programs

Answer 7

Salmonellosis - Salmonella enterica

Question 8

Reservoir species for rabies? Control measures?

Answer 8

Raccoons, skunks, bats. Vaccination = control.

Question 9

Human exposed to saliva/urine/tissue of potentially positive-rabies animal. Who should you inform?

Answer 9

State vet and local public health officials

Question 10

Can be isolated from nasal passages of normal humans and horses. Is associated with wound & surgical site infections, catheter infections. Can be spread via contact with infected individuals or fomites.

Answer 10

Methicillin-Resistant Staphylococcus aureus (MRSA)

Question 11

Causes cellulitis, pneumonia, and septic arthritis in horses

Answer 11

MRSA (methicillin-resistant staphylococcus aureus)

Question 12

Horses serve as sentinels for human disease

Answer 12

EEE/WEE

Eastern/Western Equine Encephalitis

Question 13

Preventative measures for EEE/WEE

Answer 13

Mosquito control, vaccination; birds as sentinels

Bird reservoir, mosquito vector

Question 14

In humans, causes flu-like symptoms, nausea, v+/d+, conjunctival congestion, & neuro signs

Answer 14

EEE/WEE

Question 15

Which zoonoses have wild bird reservoirs and mosquito vectors?

Answer 15

EEE/WEE/VEE and West Nile Virus

WNV: horses = incidental hosts (unless infected with chronic, high-level viremia)

Question 16

80% of humans are asymptomatic if infected with this, while 20% develop flu-like symptoms. 1:150 develop fatal, neuroinvasive illness.

Answer 16

West Nile Virus

Question 17

Is endemic to the Americas; occurs during warmer months in SW USA’s riverways & valleys

Answer 17

Vesicular Stomatitis

Question 18

Has a short incubation period (2-4d) and causes excessive salivation, blister-like oral, nasal and hoof (lameness) lesions

Answer 18

Vesicular Stomatitis

Question 19

Best prevention measures for vesicular stomatitis?

Answer 19

PPE + gloves

mainly found in laboratory personnel in humans

Question 20

Is spread by contamination via transcutaneous or transmucosal routes by sand flies, biting midges, and black flies

Answer 20

Vesicular Stomatitis

only found in the Americas, and warm months in SW USA

Question 21

Prevalent in SD, AK, MO, LA, TX and CA during warm/dry conditions. Prevention = vaccination of animals in these endemic areas.

Answer 21

Anthrax (Bacillus anthracis)

Question 22

Treatment of Anthrax in humans versus equids

Answer 22

Equids: penicillin
Humans: penicillin & ciprofloxacin

Question 23

Most common anthrax condition in humans versus most severe

Answer 23

Most common = cutaneous
Most severe = pulmonary

Question 24

Which two conditions are foreign animal diseases? Where?

Answer 24

1. Hendra Virus - Australia
2. Venezuelan EEE - tropical and subtropical America (Mexico + south of it)

Question 25

Endemic in Australia, horses catch by eating material contaminated with bat urine. Causes acute resp. syndrome followed by death in 1-3d in horses. Some may exhibit acute neuro dz prior to death.

Answer 25

Hendra virus

Question 26

VEE: endemic vs epidemic strains

Answer 26

Endemic: maintained in stable transmission b/w rodents (reservoir hosts) & mosquitoes (vector)

Epidemic: endemic mosquito (vector) infects horse -> naïve mosquito feeds off infected horse -> humans infected by now-infected mosquito -> epizootic vector (mosquito) infects horse (host)

Question 27

How does VEE differ from EEE/WEE regarding reservoir host?

Answer 27

VEE: reservoir = rodents (endemic)

EEE/WEE: reservoir = birds