Immunization Breakthrough for Deadly Elephant Viral Disease

Scientists have made a breakthrough in developing a new immunization to combat a fatal virus that targets juvenile elephants.

The inoculation, developed by an global scientific group, 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 Chester Zoo, the vaccine was found to be safe and, importantly, to stimulate part of the body's defenses that assists in combating viruses.

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

It is hoped that the result of this pioneering trial will pave the way to preventing the fatalities of young elephants from the harmful disease caused by this virus.

Devastating Impact

EEHV has had a especially destructive impact in captive environments. At one facility by itself, multiple baby elephants have died to it over the past ten years. It has also been detected in natural populations and in some sanctuaries and elephant orphanages.

It causes a haemorrhagic disease - uncontrolled hemorrhaging that can be fatal within a day. It leads to death in more than 80% of instances in juvenile elephants.

Understanding the Threat

Why EEHV can be so dangerous is remains unknown. Many mature elephants host the virus - apparently with no negative impact on their well-being. But it is believed that young calves are especially susceptible when they are being weaned, and when the protective defenses from the mother's milk decrease.

At this phase, a young elephant's immune system is in a delicate balance and it can become overpowered. "It may lead to extremely serious disease," Dr Katie Edwards stated.

"It does affect elephants in nature, but we lack an exact number of how many fatalities in total it has caused. For elephants in human care however, there have been more than 100 deaths."

Immunization Creation

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

The researchers incorporated this vaccine structure with proteins from EEHV - non-infectious parts of the virus that the elephant's immune system might identify and react against.

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

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

"They showed, clearly that the vaccine was effective to stimulate the generation of T cells, that are vital to combating viral infections."

Future Steps

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

The current vaccination requires multiple shots to be administered, so another aim is to work out if the equivalent effective amount can be given in a simpler way - perhaps with less jabs.

The conservation scientist clarified: "In the end we want to employ this vaccine in the elephants that are in danger, so we need to ensure that we can get it to where it's needed."

Prof Steinbach added: "We believe this is a major step forward, and not just only for the elephants, but because it also demonstrates that you can develop and apply vaccines to help endangered species."