Researchers in Australia and the US have uncovered genetic data they believe may contain the key to developing a vaccine for African Swine Fever (ASF).
Scientists from CSIRO’s AAHL, Kansas State University and Lawrence Livermore National Laboratory compared immune system responses, at the genetic level, in pigs infected with low versus high virulence strains of the ASF virus and were able to identify a set of common responses.
The next step is to target these common genetic responses as the basis for vaccine development and diagnostic tests. So far, attempts to develop a vaccine for ASF using conventional methods have failed.
Dr David Williams, based at CSIRO’s Australian Animal Health Laboratory said: “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.
“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.”
We will continue working with the genetic information we have identified to further our understanding of the host’s response to ASF infection and what effect this has on virus replication.”
He said the availability of a vaccine and better diagnostic capability would go a long way towards halting the spread and managing future outbreaks of what is one of the world’s most damaging pig diseases.
Although ASF has usually been restricted to Africa, in recent years it has emerged and spread steadily across Eastern Europe in wild boar and domestic pigs and there is growing concern it will continue to China and beyond.
The past few months have seen the first cases recorded in the Czech Republic and Romania, while earlier this year 10,000 pigs had to be culled in Latvia as part of ASF control measures. Recently it was reported that 16,000 pigs had to be culled on farm in Russia, where overall losses due to ASF between 2007 and 2012, are estimated at around US$ 1 billion.
The impacts of ASF include death and sickness in domestic pigs, loss of trade and the costs associated with outbreak response and eradication measures. It can often have severe socioeconomic effects on rural farmers as entire herds may be lost in an outbreak, Dr Williams said.
“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,” he added.
Dr Raymond Rowland from Kansas State University and co-author on an article published in Nature, said the work represented the benchmark study for all future work done in this area.