Researches on African Swine Fever Genotype Ⅰ/Ⅱ Recombinant Viruses and Relevant Considerations
Genetic recombination is widely present in the genomes of African swine fever virus(ASFV),contributing to the genetic diversity of ASFV.ASFV genotype Ⅱ strain was introduced to China in 2018,and genotype Ⅰ and Ⅰ/Ⅱrecombinant viruses were detected and reported in 2021.The genotype Ⅰ/Ⅱ recombinant strains isolated in China were characterized by a hybridization of two genotype sequences,merging their biological properties,and the virulence was comparable to the highly pathogenic genotype Ⅱ strain(pig/HLJ/18),even with higher indicators of pathogenicity;pigs infected with the recombinant strains could not be protected by genotype Ⅱ attenuated live vaccine strains.The evolution of ASFV might be influenced by the prevalence and evolution of these strains,posing new challenges to the development of ASFV vaccines.The information on domestic ASFV genotype Ⅰ/Ⅱ recombinant viruses was reviewed,and relevant researches were summarized,with a view to providing a reference for future prevention and control of ASF in China.