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Scientists have achieved a major advance in creating a novel vaccine to combat a fatal virus that targets juvenile elephants.

The inoculation, produced by an global research team, is designed to stop the severe illness caused by EEHV, which is presently a leading cause of death in young Asian elephants.

In trials that included adult elephants at Chester Zoo, the vaccine was found to be safe and, crucially, to activate part of the body's defenses that assists in combating viruses.

Prof Falko Steinbach described this as "a pivotal step in our efforts to safeguard Asian elephants".

It is anticipated that the outcome of this first-of-its-kind trial will pave the way to preventing the deaths of juvenile elephants from the harmful disease caused by this virus.

Severe Consequences

EEHV has had a especially devastating effect in captive environments. At Chester Zoo by itself, seven young elephants have died to it over the past ten years. It has also been detected in natural populations and in some refuges and elephant orphanages.

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 juvenile elephants.

Comprehending the Danger

Why EEHV can be so dangerous is still unknown. Many mature elephants carry the virus - seemingly with no negative impact on their health. But it is believed that juvenile elephants are especially vulnerable when they are being transitioned from milk, and when the immune-boosting defenses from the maternal nutrition decrease.

At this phase, a young elephant's natural defenses is in a precarious state and it can become overwhelmed. "It may lead to extremely serious illness," a lead conservation scientist stated.

"It impacts elephants in nature, but we don't have an exact number of how many deaths in overall it has resulted in. For elephants in human care though, there have been more than 100 deaths."

Vaccine Development

The research team, headed by animal health experts, created the new vaccine using a proven "scaffold". Essentially, the core design of this vaccine is the same to one commonly employed to immunise elephants against a virus called cowpox.

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

In a pioneering trial, the team tested the novel vaccine in three healthy, adult elephants at Chester Zoo, then analysed blood tests from the vaccinated animals.

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

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

Future Steps

The next step for the researchers is to try the vaccine in more juvenile elephants, which are the animals most vulnerable to severe disease.

The present immunization involves four injections to be administered, so an additional objective is to determine if the equivalent protective dose can be provided in a simpler way - possibly with less jabs.

The conservation scientist clarified: "In the end we aim to use this vaccine in the elephants that are at risk, so we want to make sure that we can deliver it to where it's necessary."

The project lead continued: "We believe this is a significant step forward, and not necessarily solely for the elephants, but because it additionally demonstrates that you can design and use vaccines to assist endangered species."