Maria Sol Perez Aguirreburualde at the University of Minnesota keeps a global watch on African Swine Fever for the Swine Health Information Centre.
She said the recombinant strains are highly lethal and transmissible in pigs.
Based on preliminary evidence, current live-attenuated vaccines based on ASFV genotype II, such as those being implemented in countries such as Vietnam and the Philippines, are most likely not protective against these recombinant genotype I/II strains, she said.
They have spread within China and to Vietnam and across China’s border with Russia.
There are also some new strains that are not very deadly and they have been detected in Italy, Sardinia and Africa.
The first case of African Swine Fever was in 2018 in China.
So far the closest outbreak to North America has been in the Dominican Republic.
