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

The inoculation, developed by an global scientific group, aims to prevent the severe illness caused by EEHV, which is presently a leading cause of death in juvenile Asian elephants.

In trials that involved adult elephants at Chester Zoo, the vaccine was found to be safe and, crucially, to stimulate components of the immune system that helps combating viruses.

A lead scientist described this as "a pivotal step in our efforts to protect Asian elephants".

It is anticipated that the outcome of this pioneering trial will open the door to preventing the fatalities of juvenile elephants from the dangerous condition caused by this virus.

Severe Consequences

EEHV has had a especially destructive effect in zoos. At one facility alone, multiple baby elephants have succumbed to it over the past ten years. It has additionally been found in wild elephant herds and in certain refuges and elephant orphanages.

It causes a haemorrhagic disease - uncontrolled bleeding that can be deadly within a day. It results in death in over eighty percent of cases in juvenile elephants.

Understanding the Threat

Why EEHV can be so dangerous is remains unclear. Numerous adult elephants host the virus - apparently with no negative impact on their well-being. But it is believed that juvenile calves are particularly vulnerable when they are being transitioned from milk, and when the protective defenses from the mother's milk decrease.

At this stage, a calf's natural defenses is in a delicate state and it can become overpowered. "It may lead to extremely serious disease," Dr Katie Edwards explained.

"It impacts elephants in nature, but we lack an precise count of how many deaths in total it has resulted in. For elephants in human care however, there have been more than 100 deaths."

Vaccine Development

The research team, led by veterinary scientists, created the new vaccine using a tried and tested "framework". Basically, the core design of this vaccine is the same to one routinely used to immunise elephants against a virus called cowpox.

The scientists seeded this immunization framework with components from EEHV - non-infectious bits of the virus that the animal's immune system might identify and react against.

In a pioneering experiment, the team tested the novel vaccine in three fit, mature elephants at Chester Zoo, then analysed blood samples from the innoculated animals.

Prof Steinbach stated that the findings, published in a research publication, were "more successful than anticipated".

"They showed, unequivocally that the vaccine was effective to activate the production of T cells, that are crucial to combating viral infections."

Future Steps

The subsequent phase for the researchers is to try the vaccine in younger elephants, which are the creatures most vulnerable to serious disease.

The current immunization requires four injections to be given, so an additional objective is to work out if the same effective dose can be provided in a simpler way - perhaps with fewer injections.

The conservation scientist explained: "Ultimately we aim to use this vaccine in the elephants that are at risk, so we need to ensure that we can get it to where it's necessary."

The project lead added: "We think this is a major step forward, and not just solely for the elephants, but because it additionally shows that you can develop and apply vaccines to assist endangered species."