🔗 Share this article

Researchers have achieved a major advance in creating a novel immunization to combat a fatal virus that affects juvenile elephants.

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

In trials that involved adult elephants at the facility, the vaccine was found to be harmless and, importantly, to activate part of the immune system that helps fighting viruses.

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

It is hoped that the result of this pioneering trial will open the door to averting the fatalities of young elephants from the dangerous condition caused by this virus.

Severe Consequences

EEHV has had a especially devastating effect in captive environments. At Chester Zoo alone, seven baby elephants have died to it over the past ten years. It has also been found in natural populations and in certain refuges and care centers.

It causes a haemorrhagic disease - unchecked hemorrhaging that can be fatal within 24 hours. It results in death in more than 80% of cases in young elephants.

Comprehending the Danger

Why EEHV can be so dangerous is still unclear. Many adult elephants host the virus - apparently with no adverse effects on their well-being. But it is thought that young elephants are particularly vulnerable when they are being weaned, and when the protective defenses from the mother's milk decline.

At this phase, a calf's natural defenses is in a delicate state and it can become overwhelmed. "It can cause really severe disease," a lead conservation scientist explained.

"It does affect wild elephants, but we lack an exact number of how many deaths in overall it has resulted in. For elephants in captivity though, there have been more than 100 deaths."

Vaccine Development

The scientific group, headed by veterinary scientists, created the new vaccine using a proven "scaffold". Essentially, the basic structure of this vaccine is identical to one commonly employed to vaccinate elephants against a virus called cowpox.

The researchers incorporated this vaccine structure with components from EEHV - harmless bits of the virus that the animal's immune system might identify and respond to.

In a world-first trial, the team evaluated the novel vaccine in several fit, mature elephants at the zoo, then examined blood samples from the innoculated animals.

Prof Steinbach stated that the findings, published in a research publication, were "better than we had hoped for".

"They showed, clearly that the vaccine was effective to activate the production of immune cells, that are crucial to fighting virus attacks."

Future Steps

The subsequent phase for the scientists is to test the vaccine in more juvenile elephants, which are the animals most vulnerable to severe disease.

The present vaccination involves four shots to be administered, so another aim is to work out if the same effective dose can be provided in a more straightforward way - possibly with fewer jabs.

Dr Edwards clarified: "Ultimately 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 necessary."

The project lead continued: "We believe this is a major advancement, and not necessarily only for the elephants, but because it also demonstrates that you can design and apply vaccines to help threatened animals."