Transmission of foot-and-mouth disease virus from experimentally infected Indian buffalo (Bubalus bubalis) to in-contact naïve and vaccinated Indian buffalo and cattle

This study investigated the transmission of foot-and-mouth disease virus (FMDV) from experimentally infected Indian buffalo to in-contact naïve and vaccinated cattle and buffalo. In each of six rooms, two donor buffalo that had been inoculated with FMDV were housed for five days with four recipient animals, comprising one vaccinated buffalo, one vaccinated calf, one unvaccinated buffalo and one unvaccinated calf. Vaccination was carried out with current Indian vaccine strain (O/IND/R2/75) and challenged on 28 days post-vaccination with an antigenically similar strain (O/HAS/34/05). All 12 donor buffalo and the six unvaccinated cattle and six unvaccinated calves developed clinical signs of foot-and-mouth disease (FMD). In contrast, all six vaccinated cattle (100%) and four out of six vaccinated buffalo (66.6%) were protected from disease but all became infected with FMDV. This confirms that buffalo have the potential to spread FMD by direct contact and that vaccination can block this spread. The numbers of animals in the study were too small to determine if the differences in clinical protection afforded by vaccination of cattle and buffalo are significant and warrant a different dose regime.