25 Oct 2018

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 succumbed to the fast acting Elephant endotheliotropic herpesvirus (EEHV) today.

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

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

A team of expert scientists, conservationists, keepers and vets worked tirelessly to administer anti-viral drugs to help the young elephants to fight the illness. The team also performed ground-breaking elephant blood transfusion procedures to help their immune systems fight back. Despite the exhaustive efforts, their conditions rapidly declined and both calves passed away this morning.

The duo were part of an international conservation breeding programme for the endangered species.

The zoo’s director of animals Mike Jordan said:

Aayu and his half-sister Nandita were wonderful, confident and energetic calves, who loved nothing more than playing with the rest of the family herd – whether in the sand or the pool. They will be missed by their young siblings in the herd who will no doubt mourn for a short time. To lose them both is also devastating to all of us here who have cared for them day in, day out. We fought for them until the very last moments, but were unable to save them. It is just heart-breaking.

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