Conservationists at Chester Zoo have confirmed the loss of two young elephants to a virus for which there is currently no cure.

Three-year-old Nandita Hi Way and 18-month-old Aayu Hi Way both succumbed to the fast acting Elephant endotheliotropic herpesvirus (EEHV) today. The infants were two much-loved members of the zoo's family herd of rare Asian elephants.

EEHV is known to be present in almost all Asian elephants, both in the wild and in zoos worldwide. It only develops into an illness in some elephants; 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. A team of scientists, conservationists, keepers and vets administered anti-viral drugs to help the young elephants to fight the illness. The team also performed new 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.

Mike Jordan

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.

There are currently no vaccinations against it, but researchers are working to create a treatment. 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.