The present invention relates to attenuated African Swine Fever viruses. The attenuated viruses protect pigs against subsequent challenge with virulent virus. The present invention also relates to the use of such attenuated viruses to treat and/or prevent African Swine Fever. The invention also relates to EP402R proteins of African Swine Fever virus comprising particular amino acid substitutions, as well as polynucleotides encoding such proteins and African Swine Fever viruses comprising such proteins.

A recombinant vector containing the immunogenic protein of African swine fever virus, a recombinant bacterium and use thereof, and relates to the technical field of gene recombination. The recombinant vector can be used to construct a recombinant Lactobacillus expressing the immunogenic protein of African swine fever virus, and after mixing the Lactobacillus solution that can secrete protein p72 and protein p54, respectively, an oral live bacterial preparation for preventing African swine fever can be prepared. The oral live bacteria preparation prepared by the disclosure can safely, effectively and quickly prevent the infection of African swine fever virus to pigs, and does not contain an immune process.

Provided is an African swine fever virus chimeric protein. The chimeric protein comprises: (1) an African swine fever virus p72 domain I; (2) an African swine fever virus p72 domain II; (3) an African swine fever virus p72 domain III; and (4) an African swine fever virus antigenic protein. By using African swine fever virus p72 protein as a skeleton, the chimeric protein provided in the present invention will exhibit antigenic epitopes of African swine fever virus antigenic proteins p54, p30, CD2v, and p12, achieve a good immune effect, and can produce significant humoral and cell-mediated immune response.

A method for generating progeny of an African swine fever (ASF) virus includes providing an isolated or purified fetal porcine lung alveolar macrophage cell capable of replicating the ASF virus, wherein the cell is cultured for at least 5 passages; exposing the cell to the ASF virus; and allowing the ASF virus to replicate in the cell; thereby generating progeny of the ASF virus.