Equine Infectious Anemia

Question 1

What are two other names for this disease?

Answer 1

Coggins disease and swamp fever

Question 2

What type of virus is EIA?

Answer 2

A retrovirus

Question 3

T or F: An infected horse will eventually eliminate the disease.

Answer 3

False; an infected horse will remain infected for life

Question 4

Where in a horses body is the virus present?

Answer 4

In white blood cells, mainly monocytes (is also carried in macrophages)

Question 5

What is the reservoir host for this disease?

Answer 5

Asymptomatic chronic carrier horses

Question 6

T or F: EIA has very low morbidity and mortality rates.

Answer 6

False. EIA can be a cause of significant morbidity and mortality.

Question 7

When a horse is clinically ill the virus is found where?

Answer 7

In all body tissues.

Question 8

EIA is regulated by _______…

Answer 8

The states veterinary regulatory agency and the state legislature

Question 9

Incubation period is ___ to ___ days or _____

Answer 9

15 to 45 days or longer

Question 10

What are the phases of this disease?

Answer 10

Phase 1 - acute phase
Phase 2 - subacute phase (recurring episodes)
Phase 3 - subclinical asymptomatic phase

Question 11

What are the clinical signs of phase 1?

Answer 11

Fever, depression, thrombocytopenia

Question 12

What are the clinical signs of phase 2?

Answer 12

Fever, thrombocytopenia, muscle weakness, dependent edema, anemia, petechiation, and emaciation

Question 13

What happens in Phase 3?

Answer 13

Horses become subclinical carriers or reservoir hosts for EIA.

Question 14

How long does phase 1 last?

Answer 14

1 to 3 days

Question 15

What are two things that can cause a relapse of EIA.

Answer 15

1. Stress

2. Treatment with corticosteroids

Question 16

How can EIA be transmitted?

Answer 16

• Biting flies
• Iatrogenic
• Blood transfusions
• Transplacental if mares have high viremia

Question 17

What are some biting flies that carry EIA from horse to horse?

Answer 17

Deer flies, horse flies, and sometimes stable flies

Question 18

How is EIA diagnosed?

Answer 18

Using the Agar Gel Immunodeficiency (AGID)

Question 19

What is another name for this test?

Answer 19

Coggins Test

Question 20

When may a false positive occur?

Answer 20

• When a foal is nursing on an EIA positive mare. (due to colostral antibodies).
• Foals born to a seropositive mare (positive for 6 to 8 months)

Question 21

When may a false negative occur?

Answer 21

Within the first few weeks of infection.

Question 22

What should you do if a foal under 6 months of age tests positive for EIA?

Answer 22

Retest them when they are old enough for the colostral antibodies to no longer be detectable.

Question 23

What are the treatment guidelines for EIA?

Answer 23

Supportive and symptomatic care

• Rest
• Good nutrition
• Blood transfusions

Question 24

What should be done with subclinically infected horses?

Answer 24

They should be kept in a screened stall (to keep flies away) and not allowed to go out on the pasture.

Question 25

What are the control guidelines for EIA?

Answer 25

• Control the vectors (insecticide sprays)
• Use good stable hygiene, clean needles, and surgical instruments
• Isolate positive horses and keep them 200 meters away from other horses
• Regularly test all horses for Coggins disease

Question 26

What are the rules regarding EIA for the transport of horses across state lines and entering shows and competitions?

Answer 26

A negative Coggins test is required within no more than one year before transport or events.

Question 27

How often should horses be tested?

Answer 27

Annually and more often in high risk areas.

Question 28

How far should infected horses be kept away from other horses? Why?

Answer 28

200 meters, because it is transmitted by biting flies but flies wont travel that far for feeding.

Question 29

What are the guidelines for horses being sold or going to auction?

Answer 29

They must test negative prior to the change of ownership or going to a sale barn.

Question 30

The Coggins test is what type of test?

Answer 30

A serum antibody test.