BTVPUR AlSap 8 vaccine shown to protect offspring from bluetongue virus

Newly published research from Merial Animal Health shows vaccination with their BTV-8 killed vaccine provides protection against transplacental transmission of the virus.

A study was conducted on the safety of Merial’s inactivated BTV-8 vaccine during pregnancy on a BTV-free dairy farm in France from the beginning of March 2008 until December. During the course of the study, a natural outbreak of the disease occurred and 46 pregnant cows, half of which were vaccinated with Merial’s BTV-8 killed vaccine, were exposed to the disease.

The non-vaccinated cattle tested virus positive during the outbreak, whereas virus was not detected in any of the vaccinated cows

At the time of the spread in the herd the dams were in their second or third trimester of pregnancy. 43% of the non-vaccinated cows subsequently gave birth to calves found to be infected with BTV-8 virus. However, none of the calves born from vaccinated cows were shown to be BTV-8 virus positive.

Merial Veterinary Advisor Brian Rice said: "This study not only demonstrates that BTV-8 virus can be passed from pregnant dams to their offspring but it also provides for the first time clear evidence that vaccination with BTVPUR Alsap 8 can prevent that route of virus transmission.

"Transplacental transmission of BTV-8 may be an important mechanism whereby virus can over-winter in cattle herds when midges are not present and highlights the importance of controlling and preventing bluetongue disease through vaccination. The study also clearly illustrates Merial’s BTV-8 vaccine, BTVPUR AlSap 8’s prevention of viraemia in the field."