Scientists from The Pirbright Institute say they are a step closer to developing a vaccine for African swine fever (ASF). The study, published in Vaccines, revealed that 100% of pigs immunized with the Pirbright vaccine were protected from a lethal dose of ASF virus. This is the first time that a vectored vaccine has shown a protective effect against ASF.
Scientists created a vectored vaccine by inserting eight strategically selected ASF virus genes into a vector (a non-harmful virus), according to a Pirbright release. The vectors deliver the genes to pig cells where they produce viral proteins that “prime the pig immune system” to rapidly respond to an ASF infection.
This combination of eight virus genes protected pigs from severe disease after being challenged with a strain of ASF virus. However, clinical signs of disease did develop, the release said.
Further development is needed, Pirbright scientists said. However, if this vaccine proves successful, Pirbright says the vaccine would enable the differentiation of infected animals from those that have received a vaccine (DIVA), which would allow vaccination programmes to be established without sacrificing the ability to trade.
“Demonstrating that our vaccine has the potential to fully protect pigs against ASF is a huge step in our vaccine development program. We have already begun work to refine the genes included in the vaccine to improve its effectiveness and provide more protection,” said Chris Netherton, head of Pirbright’s ASF Vaccinology Group, in the release.
ASF continues to spread across Eastern Europe and Asia, resulting in the death of over 7 million pigs globally in 2019 and causing major upheaval to the global protein market.
“This is a very encouraging breakthrough and it means we are one step closer to safeguarding the health of our pigs and the wider industry’s role in global food supply from African swine fever,” said Christine Middlemiss, the UK’s Chief Veterinary Officer, in the release.
ASF is a deadly disease of pigs only – it does not pose any threats to human health or food safety. For more information, read PorkBusiness.com/ASF.
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