Researchers have achieved a breakthrough in creating a new vaccine to combat a deadly virus that affects young elephants.
The vaccine, developed by an global scientific group, aims to prevent the serious illness caused by EEHV, which is currently a leading cause of death in young Asian elephants.
In tests that included mature elephants at Chester Zoo, the vaccine was found to be harmless and, importantly, to stimulate components of the immune system that assists in fighting viruses.
A lead scientist described this as "a landmark moment in our work to safeguard Asian elephants".
It is hoped that the outcome of this pioneering trial will open the door to averting the deaths of young elephants from the dangerous disease caused by this virus.
Devastating Impact
EEHV has had a particularly destructive effect in captive environments. At one facility by itself, multiple young elephants have died to it over the past ten years. It has additionally been detected in wild elephant herds and in certain sanctuaries and elephant orphanages.
It causes a bleeding disorder - unchecked bleeding that can be deadly within 24 hours. It results in death in over eighty percent of cases in young elephants.
Understanding the Threat
Why EEHV can be so dangerous is remains unclear. Many adult elephants host the virus - seemingly with no negative impact on their health. But it is believed that juvenile elephants are especially susceptible when they are being weaned, and when the protective defenses from the maternal nutrition decrease.
At this phase, a calf's immune system is in a precarious balance and it can become overwhelmed. "It may lead to really severe illness," Dr Katie Edwards stated.
"It does affect elephants in nature, but we lack an exact number of how many fatalities in overall it has caused. For elephants in human care however, there have been over a hundred deaths."
Vaccine Development
The research team, led by veterinary scientists, developed the novel 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 scientists seeded this vaccine structure with proteins from EEHV - non-infectious bits of the virus that the animal's defense system might recognise and react against.
In a world-first experiment, the team tested the novel vaccine in several healthy, adult elephants at Chester Zoo, then examined blood tests from the innoculated animals.
The lead researcher commented that the findings, released in a research publication, were "more successful than anticipated".
"They showed, unequivocally that the vaccine was effective to stimulate the production of T cells, that are vital to fighting viral infections."
Future Steps
The subsequent phase for the researchers is to test the vaccine in more juvenile elephants, which are the creatures most vulnerable to serious disease.
The present immunization requires four injections to be administered, so an additional objective is to determine if the equivalent protective dose can be given in a more straightforward way - perhaps with fewer injections.
Dr Edwards explained: "In the end we want to use this vaccine in the elephants that are at risk, so we need to make sure that we can deliver it to where it's necessary."
The project lead added: "We believe this is a major advancement, and not just only for the elephants, but because it also shows that you can develop and apply vaccines to help threatened animals."
