A prototype vaccine to tackle a horse virus could potentially save the lives of hundreds of thousands of equines, it has been claimed.

African Horse Sickness is a highly infectious and deadly disease spread by insect vectors. Image: David Mullins.
African Horse Sickness is a highly infectious and deadly disease spread by insect vectors. Image: David Mullins.

African horse sickness (AHS) is one of the deadliest viruses to affect horses, causing up to 90% mortality in susceptible animal populations and economic losses for the equine industry as a result.

Caused by a virus transmitted by Culicoides biting midges, AHS is endemic in central and sub-Saharan Africa. Major outbreaks have also been reported in the Middle East, India, Pakistan, Spain, Portugal and Morocco.

Vaccines that use the live attenuated virus are available in some countries where the virus persists, but are not considered safe enough for licensed use in countries where the virus is not present.

Vaccine strategy

However, scientists at The Pirbright Institute have developed a recombinant vaccine strategy – one resulting from new combinations of genetic material – to address the issue.

Lead scientist Javier Castillo-Olivares, a world expert on AHS, said: “We have developed a prototype vaccine that is safe, effective and can potentially be used in non-endemic and endemic countries.

“The vaccine uses modified vaccinia Ankara virus, which is innocuous to horses, to carry and deliver the gene of AHS virus that makes the molecule inducing protection against AHS virus.

“We have shown what the mechanism of protection for this type of vaccine is and that it would improve differentiation of infected animals from vaccinated animals when used in conjunction with a diagnostic test already in use.”

Multiple serotype protection

Dr Castillo-Olivares added: “We have also shown this type of vaccine is suitable for applying in combinations to provide protection against multiple serotypes.

“Furthermore, by demonstrating vaccine immunity correlates with the levels of antibodies circulating in the vaccinated animal, we are on the right path to be able to predict what level of protection a horse would have just by looking at the antibody levels in the blood.”

  • Read more about the vaccine, including the strategy to bring it to market, in the 11 July issue of Veterinary Times.
View your activity >

Leave a Reply

Be the First to Comment!

Notify of


related content

The RCVS has announced the winners of this year’s Queen’s Medal and Golden Jubilee Award – the highest honours the college can bestow on a veterinary surgeon and veterinary nurse.

4 mins

Brooke, The Donkey Sanctuary, SPANA and World Horse Welfare have formed a coalition that aims to support the implementation of the first ever global welfare standards for working horses, donkeys and mules.

4 mins

Total of 19 awards handed out in glittering ceremony to celebrate best in veterinary and animal health marketing.

5 mins

Anna Bruguera looks at bovine viral diarrhoea, its transmission, recognising clinical signs and UK eradication schemes in place.

34 mins

Andrew Kent looks at the aetiology, diagnosis, treatment options and monitoring of this common condition presenting in dogs

30 mins

Vets and VNs are being urged to help raise awareness about the threat from ticks, as well as the preventive measures to protect dogs, cats and their owners from the risk of tick-borne illnesses, such as Lyme disease.

5 mins