Immunological Evaluation of Influence of Dose and Route of Immunization with FMD Serotype ‘A’ Vaccine in Guinea Pigs

A study has been conducted to measure the immunization efficacy of route of inoculation between intra dermal (ID) and intra muscular (IM) in guinea pigs, using FMD vaccines. Three different vaccine formulations of varying concentrations containing full dose, 1/5th dose, 1/10th dose were prepared and injected either intra muscularly or intra dermal to six different groups of guinea pigs. At 30th day post vaccination, all the animals were challenged. Efficacy of route was defined in terms of serum neutralizing antibodies, IgG1 and IgG2 isotype response and challenge studies. When compared with guinea pigs that were intramuscularly vaccinated with a full dose vaccine, guinea pigs vaccinated intra dermal with 1/5th dose of the vaccine were 60% protected against clinical disease. Thus, we conclude that ID route is a good alternative for IM route, as ID route has shown to induce a very efficient immunological response against FMD. Moreover, the dose required by the ID route is lower compared to the IM route with an added benefit of reduced requirement of antigen and costs per dose of FMD vaccine.