Evaluation of the serological response after foot-and-mouth disease vaccination in Pakistan

Among viral diseases, Foot and Mouth Disease is a highly contagious, economically important disease of cloven-hoofed animals caused by a virus of the genus Aphthovirus, family Picornaviridae. A total of 12 calves of about one year old with proper tags were selected for the study. These animals were divided into four groups i:e A, B, D (each having 3 animals) and Group C as a control group having 3 animals (including one positive and two negative control animals). Blood samples were collected on day zero. On day zero, 03 groups (A, B & D) were vaccinated with 3ml FMDRL Trivalent Foot and Mouth Disease Vaccine (Oil-based) simultaneously. On the 28th of Priming dose, Group A was given a booster dose, while Group B, along with a positive control, were challenged with live virus. Group D was reared as such with a priming dose. Group B, along with the positive control, were examined for the next 10 days for any pathognomic signs related to FMD. In clinically positive case the signs developed and the animals were tested for the FMD virus. Antibody titer of all the groups was checked through ELISA on the 28th day and then every 30 days after for 12 months. The protection provided by the “O”, “A”, and “Asia1” serotypes in the vaccine on the priming dose was 10, 06, and 06 months, respectively. Similarly, the protective titer provided by the “O”, “A”, and Asia1 serotypes in the vaccine on the boosting dose was 13, 13, and 12 months, respectively. The antibody titers provided by the animals of group D (with infection) were 10, 08, and 08 months for O, A, and Asia1. From the present study, it is concluded and recommended that the FMDRL vaccine is collectively effective and provides a protective titer against all serotypes for at least 06 months on a single dose. However, further studies may be conducted to elucidate the protection provided by the vaccine.

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