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Researchers have achieved a major advance in creating a novel vaccine to prevent a deadly virus that affects juvenile elephants.

The vaccine, developed by an international research team, is designed to prevent the severe disease caused by EEHV, which is currently a leading cause of death in juvenile Asian elephants.

In tests that involved adult elephants at the facility, the vaccine was found to be safe and, importantly, to stimulate components of the immune system that assists in combating viruses.

A lead scientist called this as "a landmark moment in our efforts to protect Asian elephants".

It is hoped that the result of this first-of-its-kind study will pave the way to preventing the deaths of young elephants from the dangerous condition caused by this virus.

Severe Consequences

EEHV has had a particularly destructive impact in zoos. At Chester Zoo by itself, seven young elephants have died 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 fatal within a day. It leads to death in over eighty percent of instances in young elephants.

Comprehending the Danger

Why EEHV can be so dangerous is remains unknown. Numerous mature elephants carry the virus - apparently with no adverse effects on their well-being. But it is thought that juvenile elephants are particularly susceptible when they are being transitioned from milk, and when the immune-boosting antibodies from the mother's milk decrease.

At this phase, a calf's natural defenses is in a precarious balance and it can become overpowered. "It can cause really severe disease," a lead conservation scientist stated.

"It impacts wild elephants, but we lack an exact number of how many deaths in total it has caused. For elephants in captivity however, there have been over a hundred deaths."

Immunization Creation

The scientific group, headed by animal health experts, created the novel vaccine using a proven "framework". Essentially, the basic structure of this vaccine is the same to one routinely used to vaccinate elephants against a virus called a related virus.

The scientists seeded this immunization framework with proteins from EEHV - harmless bits of the virus that the elephant's defense system might recognise and react against.

In a world-first experiment, the team tested the novel vaccine in three fit, adult elephants at Chester Zoo, then analysed blood tests from the innoculated animals.

The lead researcher commented that the results, published in a scientific journal, were "more successful than anticipated".

"The results demonstrated, clearly that the vaccine was effective to activate the production of T cells, that are vital to combating viral infections."

Future Steps

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

The current vaccination requires four shots to be given, so another aim is to determine if the equivalent protective amount can be given in a simpler way - perhaps with less injections.

Dr Edwards explained: "Ultimately we aim to employ this vaccine in the elephants that are in danger, so we need to make sure that we can deliver it to where it's needed."

Prof Steinbach continued: "We think this is a significant step forward, and not necessarily only for the elephants, but because it also demonstrates that you can develop and use vaccines to help endangered species."