GREENPORT, N.Y. – Researchers with the US Dept. of Agriculture’s Agricultural Research Service (ARS) have developed a genetically modified virus that provides complete protection from a strain of African Swine Fever (ASF) responsible for recent outbreaks in East Asia and Central Europe.
In a pre-printed study published in bioRxiv, researchers said that a “previously uncharacterized gene” from the highly virulent ASF 2007 Georgia isolate (ASFV-G), produced complete protection in swine. Animals inoculated intramuscularly with the virus lacking the gene remained clinically normal during a 28-day observational period. Animals infected with the genetically modified virus (ASFV-G-ΔI177L) had low concentrations of the virus, showed no virus shedding and developed a strong virus-specific antibody response.
“…importantly, they were protected when challenged with the virulent parental strain ASFV-G,” the researchers said. “ASFV-G-ΔI177L is one of the few experimental vaccine candidate virus strains reported to be able to induce protection against the ASFV Georgia isolate, and the first vaccine capable of inducing sterile immunity against the current ASFV strain responsible for recent outbreaks.”
Analysts have estimated the virus will kill one quarter of the world’s pig population. Central and Eastern European countries are working to stamp out the disease.
China reported its first-ever outbreak of ASF in August of 2018. Since then, that country has lost more than half of its domestic swine herd to the disease. Outbreaks outside of China have occurred in Vietnam, and in North and South Korea, Cambodia, Laos and Myanmar.
Analysts at Rabobank estimate it will take five years for the worst-effected countries to rebuild swine herds and for pork production to recover. But recontamination at some slaughtering operations; new biosecurity-focused operations being built; integration of production with slaughtering to mitigate infection risks; and investments in non-pork production, specifically poultry and even plant-based proteins, all have hindered herd rebuilding in the region.