Genetic data could hold the key to African swine fever vaccine

Australian and US researchers have uncovered genetic data in pigs that may contain the key to developing a vaccine for African swine fever (ASF).

ASF is a severe problem, often resulting in high fatality rates in domestic pigs and trade restrictions upon reported outbreaks. The disease often has major socio-economic effects on rural farmers, as entire herds may be lost in a single outbreak. In Russia, overall losses due to ASF between 2007 and 2012 are estimated at around US$1 billion.

So far, attempts to develop a vaccine using conventional methods have failed. As noted by Dr David Williams, based at CSIRO’s Australian Animal Health Laboratory (AAHL), “There are no effective treatments or vaccines available for ASF, so disease control is based on the enforcement of strict quarantine and stamping out measures.”

Seeking a solution, Dr Williams and his colleagues from AHHL collaborated with Kansas State University and Lawrence Livermore National Laboratory to compare immune system responses, at the genetic level, in pigs infected with low versus high virulence strains of the virus that causes ASF. The researchers were able to identify a set of common responses, the results of which were published in the journal Scientific Reports.

“Our findings have extended our understanding of the virus–host relationship, an important element in developing new intervention strategies including new vaccine research to identify genes that stimulate protective immunity,” said Dr Williams.

“Our genetic investigations shed light on how immune system genes of pigs respond to ASF virus infection, and also how they influence virus replication in the host.”

The next step is to target these common genetic responses as the basis for vaccine development and diagnostic tests — a move which is strongly supported by the Australian pork industry.

“ASF is a terrible disease, with the most virulent strains being impossible to treat,” said Pat Mitchell from Australian Pork Ltd. “Access to a vaccine may not only assist with reducing the level of the ASF virus circulating globally, it will also dramatically improve our ability to respond to an emergency animal disease outbreak.”

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