Attenuated African swine fever virus vaccine based in the deletion of MGF genes

摘要

African swine fever virus (ASFV) is the etiological agent of a contagious and often lethal viral disease of domestic pigs. Control of ASF has been hampered by the unavailability of vaccines. Experimental vaccines have been derived from naturally occurring, cell culture-adapted, or genetically modified live attenuated ASFVs; however, these vaccines are only successful when protecting against homologous viruses. Among viral genes reported to be involved in virulence are components of the multi gene family (MGF). Here we report the construction of a recombinant ΔMGF virus derived from the highly virulent ASFV Georgia 2007 (ASFV-G) isolate. In vivo, ASFV-G ΔMGF administered intramuscularly (IM) to swine at either 10² or 10⁴ HAD₅₀ are completely attenuated; the inoculated animals are completely asymptomatic. Animals infected with 10² or 10⁴ HAD50 of ASFV-G ΔMGF are protected against the presentation of clinical disease when challenged at 28 days post infection with the virulent parental strain Georgia 2007.