Leading scientists at Chester Zoo are behind a a groundbreaking new vaccine which can now be rolled out globally.

Developed by Chester Zoo scientists, the University of Surrey and the Animal and Plant Health Agency (APHA), the vaccine targets elephant endotheliotropic herpesvirus (EEHV) - one of the most serious threats facing young Asian elephants worldwide.

The breakthrough was published last week in the prestigious journal 'Nature Communications', following a landmark proof-of-concept trial.

The vaccine was shown to be safe and effective in triggering a strong immune response - a crucial step toward preventing EEHV, a disease that can kill elephants in just 24 hours.

EEHV poses a severe threat to the survival of Asian elephants (Image via: Chester Zoo)

"This is a critical turning point," said researchers involved in the study. "Until now, EEHV has been a silent killer. With this vaccine, we finally have a weapon to fight back."

EEHV poses a severe threat to the survival of Asian elephants, a species already listed as endangered on the IUCN Red List, with fewer than 40,000 individuals remaining in the wild.

Fatal cases have been documented across India, Nepal, Myanmar, Thailand, and beyond - with the disease affecting both wild populations and vital conservation breeding programmes in zoos worldwide.

The virus has also been detected in African elephants.

"This vaccine has been in development for several years and was first delivered to an elephant here at Chester Zoo in 2021," said Dr Katie Edwards, lead conservation scientist at Chester Zoo and co-author of the study.

"The publication of this research marks a watershed moment because it means we can now say that the vaccine is ready for wider use.

"EEHV has taken the lives of so many elephants, both in human care and in the wild, but this vaccine offers hope.

"We can't yet say this will be the end of EEHV deaths, but we have taken a massive step towards that goal."

The vaccine is given via injection with booster doses, making it ideal for use in zoos and sanctuaries, with plans underway to develop delivery methods suitable for wild populations.

Dr Javier Lopez, Head of Veterinary Services at Chester Zoo, emphasised the scale and urgency of the effort.

He said: "I'm incredibly proud of the team. It's taken years of hard work, collaboration and sheer determination to get to this point.

"Now, time is critical – this disease can kill within 24 hours.

"That's why we're working to clear the legal and logistical hurdles needed to send the vaccine worldwide.

"This is a critical turning point. Until now, EEHV has been a silent killer. With this vaccine, we finally have a weapon to fight back."