A conditional license has been issued by USDA for a new killed-virus vaccine against swine influenza virus (SIV), caused by the new strain of the virus, H3N2.

"If animals in an SIV-vaccinated herd run high fevers, abort and there are deaths, it may be a tip-off that the H3N2 strain is present," points out Rick Sibbel, DVM, technical service veterinarian for vaccine licensee Schering-Plough Animal Health.

"In these cases, testing for H3N2 should be arranged and all healthy swine should be vaccinated."

The conditionally licensed vaccine will be available only through veterinarians and where approved by state animal health officials. To date, 15 states have approved its use. Schering-Plough will pursue a full USDA license for the new vaccine.

Schering-Plough also produces MaxiVac-Flu vaccine, to protect against the H1N1 strain. The vaccine has been used successfully in sows and baby pigs since its introduction in 1993.