Herpes

Virus

Elephant Endotheliotropic Herpesvirus (EEHV) or Elephantid betaherpesvirus 1 (ElHV-1)

Primary Host

Asian elephants (highly fatal); generally benign in African elephants

Affected Age Group

Primarily affects juvenile Asian elephants aged 1-8 years; some cases in older wild-born adults and calves

Symptoms

Lethargy, reduced appetite, swelling, oral/nasal bleeding, rapid deterioration, cyanosis, mouth ulcers, edema

Fatality Rate

Up to 80% in severely affected Asian elephants; rapid progression with death within 24 hours to 5 days

First Documented Case

1990; cases identified as early as 1983 from stored tissue samples

Virus Transmission

Proboscivirus genus; potentially transmitted via trunk secretions; discouraged contact between Asian and African elephants

Known Species/Types

EEHV1A, EEHV1B (highly fatal in Asian elephants); EEHV2, EEHV3, EEHV4, EEHV5, EEHV6

Treatment

Rapid antiviral drug (famciclovir); effective in about 1 in 3 cases; requires early identification

Documented Cases

Over 54 cases in North America and Europe; only 9 successfully treated

Impact on Populations

Significant threat to captive and wild Asian elephant populations; high mortality among young animals

Preventive Measures

Enzyme-linked immunosorbent assay testing; monitoring for antibodies; avoiding close contact between infected and healthy elephants

Key Historical Cases

First fatal case at National Zoo, Washington, D.C. in 1995

1996: First fatal case in African elephants (Kijana, an 11-month-old male)

2006: First confirmed case in Asia (young calf at Cambodia sanctuary)

2019: Successful recovery of calf Indali Hi Way at Chester Zoo

2024: Two deaths reported at Dublin Zoo (Avani, 8 years, and Zinda, 7 years)

Research & Developments

Ongoing research for vaccine development; urgent studies needed on EEHV in wild Asian populations

Transmission Avoidance

Avoid mixing Asian and African elephants; limit new contact between young captive-born and wild-born Asian elephants due to carrier risks

PRACTICE QUESTION

Q. With reference to Elephant Endotheliotropic Herpesvirus (EEHV), consider the following statements:

1. EEHV primarily affects young Asian elephants and can cause a highly fatal hemorrhagic disease.
2. The virus is exclusive to Asian elephants and is not found in African elephants.
3. Antiviral treatment is completely effective in curing all cases of EEHV infection.

Which of the statements given above is/are correct?

(a) 1 only

(b) 1 and 2 only

(c) 2 and 3 only

(d) 1, 2, and 3

Answer: (a)