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Researchers have achieved a breakthrough in developing a novel vaccine to combat a deadly virus that targets juvenile elephants.

The vaccine, developed by an global research team, aims to stop the severe disease caused by elephant endotheliotropic herpesvirus (EEHV), which is currently a leading cause of death in young Asian elephants.

In tests that involved mature elephants at Chester Zoo, the vaccine was found to be safe and, crucially, to stimulate components of the immune system that assists in combating viruses.

Prof Falko Steinbach called this as "a landmark moment in our efforts to safeguard Asian elephants".

It is anticipated that the outcome of this pioneering study will pave the way to preventing the deaths of young elephants from the dangerous disease caused by this virus.

Devastating Impact

EEHV has had a especially devastating impact in zoos. At Chester Zoo by itself, multiple young elephants have died to it over the past ten years. It has also been found in natural populations and in certain sanctuaries and elephant orphanages.

It causes a bleeding disorder - uncontrolled bleeding that can be fatal within a day. It leads to death in over eighty percent of instances in juvenile elephants.

Comprehending the Danger

Why EEHV can be so lethal is remains unclear. Many mature elephants host the virus - seemingly with no negative impact on their health. But it is believed that young calves are particularly susceptible when they are being transitioned from milk, and when the immune-boosting defenses from the mother's milk decline.

At this stage, a calf's immune system is in a precarious balance and it can become overwhelmed. "It may lead to really severe disease," Dr Katie Edwards explained.

"It does affect wild elephants, but we don't have an exact number of how many fatalities in total it has caused. For elephants in human care though, there have been over a hundred deaths."

Immunization Creation

The scientific group, headed by veterinary scientists, developed the novel vaccine using a tried and tested "framework". Essentially, the core design of this vaccine is the same to one commonly employed to immunise elephants against a virus called a related virus.

The scientists incorporated this vaccine structure with components from EEHV - non-infectious parts of the virus that the elephant's immune system might identify and react against.

In a pioneering trial, the team tested the novel vaccine in several fit, mature elephants at Chester Zoo, then analysed blood samples from the vaccinated animals.

Prof Steinbach commented that the results, released in a scientific journal, were "more successful than anticipated".

"The results demonstrated, unequivocally that the vaccine was effective to stimulate the production of immune cells, that are crucial to combating viral infections."

Future Steps

The subsequent phase for the researchers is to try the vaccine in more juvenile elephants, which are the creatures most at risk to severe illness.

The current vaccination requires multiple shots to be given, so another aim is to work out if the same effective dose can be given in a more straightforward way - possibly with fewer jabs.

The conservation scientist clarified: "In the end we want to employ this vaccine in the elephants that are at risk, so we need to ensure that we can deliver it to where it's needed."

Prof Steinbach added: "We think this is a significant advancement, and not necessarily only for the elephants, but because it additionally shows that you can develop and use vaccines to assist threatened animals."