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10 24/10/2018

Fighting EEHV

Conservationists at Chester Zoo are fighting to save the lives of two elephant calves from a vicious virus that is threatening endangered Asian elephants worldwide.

Three-year-old Nandita Hi Way and 18-month-old Aayu Hi Way – two much loved members of the zoo’s close-knit family herd of rare Asian elephants – both tested positive for the fast acting Elephant endotheliotropic herpesvirus (EEHV) on Monday 22 October.

EEHV is known to be present in almost all Asian elephants, both in the wild and in zoos across the globe, but only develops into an illness in some elephants and when it does it is almost always fatal.



Dedicated elephant keepers at the zoo detected signs of the virus in Aayu and Nandita early and, utilising state-of-the-art technology in the zoo’s on-site science lab, were able to confirm the presence of EEHV at the earliest possible moment and immediately begin treatment.

A team of expert scientists, conservationists, keepers and vets are working around-the-clock to administer anti-viral drugs to help the young elephants to fight the illness. The team have also performed ground-breaking elephant blood transfusion procedures to help their immune systems fight back.


Mike Jordan, the zoo's Director of Animals, said:

EEHV is an incredibly complex disease. It affects the membranes in elephants, so it occurs in their saliva in their mouth, in their trunk and in their gut. The virus attacks those membranes and causes a haemorrhagic fever and intense bleeding very, very rapidly.

Aayu and his half-sister Nandita are wonderful, charismatic little calves and to lose them to this horrible disease would be devastating. Our teams have acted fast and we’re doing everything we possibly can to help them fight it off.

Despite the ongoing and extensive efforts, staff at the zoo have warned that there are no guarantees of either calf’s survival.

Relatively little is known about EEHV. As well as those recorded in zoos, conservationists have discovered fatalities in at least seven countries across the Asian elephant range in the wild – India, Nepal, Thailand, Cambodia, Laos, Indonesia (Sumatra) and Myanmar.

Currently there is no vaccination against it but researchers are working to create a treatment that trains an elephant’s immune system in what to look for.

Chester Zoo scientists - backed by more than £220,000 of public donations, a major partnership with The University of Surrey, and an international collaboration of conservationists, have made real progress in the fight to find a cure - but sadly the battle is ongoing.

Scientists from Chester Zoo are at the forefront of this major international effort, which is critical if conservationists are to protect both wild and zoo elephant herds globally from the virus. If you would like to find out more information about EEHV, please read our frequently asked questions.

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