🔗 Share this article

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

The inoculation, produced by an international scientific group, aims to prevent the severe illness caused by EEHV, which is currently a leading cause of death in juvenile Asian elephants.

In trials that involved adult elephants at the facility, the vaccine was found to be harmless and, importantly, to stimulate components of the body's defenses that assists in fighting viruses.

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

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

Devastating Impact

EEHV has had a particularly devastating impact in captive environments. At one facility by itself, multiple baby elephants have died to it over the last decade. It has additionally been found in natural populations and in certain refuges and care centers.

It causes a haemorrhagic disease - unchecked bleeding that can be fatal within 24 hours. It leads to death in over eighty percent of instances in young elephants.

Comprehending the Danger

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

At this phase, a young elephant's immune system is in a precarious balance and it can become overpowered. "It can cause extremely serious illness," Dr Katie Edwards explained.

"It impacts elephants in nature, but we don't have an exact number of how many deaths in total it has caused. For elephants in human care however, there have been over a hundred deaths."

Immunization Creation

The scientific group, headed by animal health experts, developed the novel vaccine using a tried and tested "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 researchers seeded this immunization framework with proteins from EEHV - non-infectious bits of the virus that the animal's defense system might identify and react against.

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

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

"They showed, clearly that the vaccine was able to activate the generation of immune cells, that are crucial to combating viral infections."

Next Phases

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

The current immunization involves four injections to be given, so another aim is to determine if the same effective amount can be provided in a simpler way - perhaps with less jabs.

Dr Edwards clarified: "Ultimately we aim to employ 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 think this is a significant step forward, and not necessarily only for the elephants, but because it also shows that you can design and use vaccines to assist threatened animals."