🔗 Share this article Vaccine Advancement for Lethal Elephant Viral Disease Chester Zoo has lost multiple baby elephants to the illness caused by the virus Scientists have made a major advance in developing a new vaccine to combat a deadly virus that targets juvenile elephants. The inoculation, developed by an global research team, is designed to prevent the severe disease caused by elephant endotheliotropic herpesvirus (EEHV), which is presently a primary cause of death in young Asian elephants. The study involved elephants at Chester Zoo In tests that involved adult elephants at Chester Zoo, the vaccine was found to be safe and, importantly, to activate part of the body's defenses that helps fighting viruses. Prof Falko Steinbach described this as "a landmark moment in our efforts to safeguard Asian elephants". It is hoped that the result of this pioneering trial will open the door to preventing the deaths of young elephants from the harmful condition caused by this virus. Severe Consequences EEHV has had a particularly destructive impact in captive environments. At Chester Zoo by itself, seven baby elephants have succumbed to it over the last decade. It has also been detected in wild elephant herds and in some sanctuaries and elephant orphanages. It causes a bleeding disorder - unchecked bleeding that can be deadly within 24 hours. It results in death in more than 80% of cases in juvenile elephants. The next step is to evaluate the novel vaccine in more vulnerable elephants Understanding the Threat Why EEHV can be so lethal is still unknown. Numerous adult elephants host the virus - apparently with no negative impact on their health. But it is believed that juvenile elephants are particularly susceptible when they are being transitioned from milk, and when the protective defenses from the mother's milk decrease. At this stage, a calf's immune system is in a delicate state and it can become overwhelmed. "It may lead to extremely serious illness," Dr Katie Edwards stated. "It does affect wild elephants, but we don't have an precise count of how many deaths in total it has resulted in. For elephants in captivity though, there have been over a hundred deaths." Vaccine Development The scientists hope the vaccine will eventually be employed to protect elephants in their natural environment The research team, led by veterinary scientists, developed the new vaccine using a proven "scaffold". Essentially, the core design of this vaccine is identical to one commonly employed to vaccinate elephants against a virus called a related virus. The scientists seeded this vaccine structure with proteins from EEHV - harmless bits of the virus that the animal's defense system might recognise and react against. In a world-first trial, the team tested the novel vaccine in several healthy, adult elephants at Chester Zoo, then analysed blood tests from the innoculated animals. Prof Steinbach commented that the results, released in a scientific journal, were "more successful than anticipated". "The results demonstrated, unequivocally that the vaccine was effective to stimulate the production of T cells, that are crucial to fighting virus attacks." Future Steps The subsequent phase for the researchers is to test the vaccine in younger elephants, which are the animals most vulnerable to severe illness. The aim is to create a vaccine that can be transported and stored where it is required The current vaccination requires four shots to be given, so another aim is to determine if the same protective amount can be provided in a more straightforward way - perhaps with fewer injections. The conservation scientist explained: "Ultimately we aim 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 continued: "We believe this is a major advancement, and not necessarily only for the elephants, but because it additionally demonstrates that you can develop and use vaccines to assist threatened animals."