Elephant Endotheliotropic Herpesviruses (EEHVs)

Over the past year, Kerala has witnessed a notable reduction in the number of juvenile elephants, largely due to the outbreak of Elephant Endotheliotropic Herpesviruses (EEHVs).

What are EEHVs?

• EEHVs represent a group of novel double-stranded DNA viruses belonging to the herpesvirus family.
• They specifically infect Asian and African elephants, causing acute internal haemorrhaging, particularly in young calves.
• In severe cases, the infection can prove fatal within 24 hours of symptom onset.
• Though EEHVs have long coexisted with elephant populations, juvenile elephants are especially susceptible due to their low levels of virus-specific antibodies.
• Importantly, this virus is not transmissible to humans, meaning it poses no threat to public health.

Why Are Kerala’s Calves More at Risk?

• In large elephant herds, calves are naturally exposed to various EEHV strains, helping them build immunity early in life.
• In contrast, Kerala’s elephant population primarily exists in small groups or pairs—over 56% of sightings—limiting such immunity-building exposure.

Factors Contributing to Smaller Herd Sizes in Kerala

1. Degraded Habitats:
   Shrinking forest areas have led to fragmented and insufficient elephant habitats.
2. Invasive Plant Species:
   The spread of non-native trees like Acacia mangium and Eucalyptus has transformed forest ecosystems, negatively affecting biodiversity and natural fodder availability.
3. Human-Wildlife Conflict:
   Due to the shortage of food sources within the forest, elephants are increasingly venturing into agricultural fields, intensifying conflict with humans and further disrupting herd dynamics.