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Scientists have achieved a major advance in developing a novel immunization to prevent a deadly virus that targets juvenile elephants.

The vaccine, developed by an global scientific group, is designed to prevent the severe disease caused by EEHV, which is presently a leading cause of death in young Asian elephants.

In trials that involved mature elephants at the facility, the vaccine was found to be safe and, importantly, to activate part of the immune system that assists in fighting viruses.

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

It is hoped that the result of this first-of-its-kind trial will open the door to preventing the fatalities of young elephants from the dangerous condition caused by this virus.

Severe Consequences

EEHV has had a particularly devastating effect in zoos. At one facility by itself, seven young elephants have died to it over the last decade. It has additionally been detected in wild elephant herds and in some refuges and care centers.

It causes a haemorrhagic disease - unchecked hemorrhaging that can be deadly within 24 hours. It leads to death in more than 80% of instances in juvenile elephants.

Comprehending the Danger

Why EEHV can be so dangerous is remains unknown. Numerous mature elephants host the virus - apparently with no negative impact on their well-being. But it is believed that juvenile elephants are especially vulnerable when they are being transitioned from milk, and when the protective antibodies from the maternal nutrition decrease.

At this stage, a young elephant's natural defenses is in a delicate balance and it can become overpowered. "It can cause extremely serious illness," a lead conservation scientist explained.

"It does affect wild elephants, but we lack an precise count of how many deaths in total it has caused. For elephants in captivity though, there have been over a hundred deaths."

Vaccine Development

The scientific group, headed by veterinary scientists, created the novel vaccine using a proven "scaffold". Basically, the core design of this vaccine is identical to one commonly employed to immunise elephants against a virus called a related virus.

The scientists incorporated this vaccine structure with proteins from EEHV - harmless parts of the virus that the animal's defense system might identify and respond to.

In a world-first trial, the team evaluated the novel vaccine in several healthy, mature elephants at Chester Zoo, then examined blood samples from the vaccinated animals.

The lead researcher stated that the findings, published in a scientific journal, were "better than we had hoped for".

"The results demonstrated, clearly that the vaccine was effective to activate the generation of T cells, that are vital to fighting virus attacks."

Future Steps

The next step for the researchers is to try the vaccine in younger elephants, which are the animals most at risk to serious disease.

The present vaccination requires multiple injections to be given, so another aim is to determine if the same effective dose can be provided in a more straightforward way - possibly with fewer injections.

Dr Edwards explained: "In the end we want to employ this vaccine in the elephants that are in danger, so we want to ensure that we can get it to where it's needed."

Prof Steinbach added: "We think this is a major advancement, and not just only for the elephants, but because it also demonstrates that you can design and apply vaccines to assist endangered species."