Attenuation of ASF in Dominican Republic Making Detection More Difficult

Changes observed in the Dominican Republic indicate the virus responsible for the African Swine Fever outbreak there is becoming less virulent and could become more difficult to detect.

The Swine Health Information Center's global swine disease monitoring for report for December indicates the number of cases of African Swine Fever increased in November in eastern Europe and it remains a concern in Asia, southeast Asia and the Caribbean.

Dr. Paul Sundberg, the Executive Director of the Swine Health Information Center and a member of the Swine Innovation Porc Coordinated African Swine Fever Research Working Group, says ASF is relatively stable but one of the things that has been noted in the Dominican Republic is that the virus has changed.

Clip-Dr. Paul Sundberg-Swine Health Information Center:

That's a spot where we have a lot of scientific activity going on in the virus.One thing that is notable in the DR is that the virus seems to be attenuating some that it isn't causing the mortality event outbreak that has been seen before or been seen in Southeast Asia and Europe, for example.

There's been some work by USDA on Plumb Island with that virus.If you take that virus and inject it into a pig, it will cause that pig to die and it will die relatively quickly but, if you expose the pigs to the virus the way they would be naturally exposed then there's a certain percentage that are going to get sick and recover, there's a certain percentage that have the virus but don't show clinical signs and there's another percentage that are gong to get sick and die as if they were injected.

It's concerning in that it seems to be changing and attenuating some that decreases the mortality event which could make it harder to detect.

Dr. Sundberg says the virus could linger and look like other endemic diseases so there is a lot of scientific investigation underway now to understand those processes and the pig's response to the infection.