Location: Foreign Animal Disease Research2010 Annual Report
1a. Objectives (from AD-416)
This project will establish collaborative research with two institutions of the Indian Council of Agricultural Research working on FMD to conduct antigenic and genetic characterization of FMD field virus isolates, surveillance, monitoring and vaccine strain selection for FMD control programs in India.
1b. Approach (from AD-416)
Researchers from ARS, the Indian Veterinary Research Institute, and the Project Directorate on Foot and Mouth Disease (PDFMD) will: i) genetically and serologically characterize FMDV strains from cattle, buffalo and sheep circulating in endemic areas of India; ii) utilize phylogenetic and serological studies to determine the serological relationship of FMDV strains and identify viral strains conferring cross reaction against a wide range of subtypes within FMD serotypes; and iii) utilize the hAd5-vector platform to generate candidate vaccines containing the P1 region of the Indian vaccine strains (Serotypes O,A and Asia1) and any other widely reactive Indian field strains and test in pilot proof of concept experiment the serological response of animals vaccinated with the novel hAd5-FMD vaccines compared to current vaccines strains.
3. Progress Report
FMD is one of the main diseases affecting animal production and trade in India, and it is endemic and occurs throughout the country. Although the disease is not generally fatal in adult animals, it does cause severe disease, decrease in milk production, decreased body weight, and increases the risk of spontaneous abortion among pregnant animals. In addition, milk and milk products, meat, and hide are not accepted by the disease-free countries, causing reduction in the export potential of the livestock industry. Currently, serotype and subtype specific FMD vaccines are produced in India by growing large amounts of tissue culture-adapted virulent field strains that can pose a risk of escaping from manufacturing facilities or can spread by incomplete inactivation of vaccines. Other shortcomings of the current vaccine include the lack of cross protection between serotypes and subtypes, short shelf life of the formulated product, and short duration of immunity (less than six months). New vaccine platforms have been explored in the last few years with the Human Defective Adenovirus 5 Vector (hAd5) based FMD vaccine developed by the USDA, ARS being the most successful molecular vaccine to date. This research project is aimed at characterizing strains of FMDV from cattle, buffalo, and other animals circulating in endemic areas of India; and determining the vaccine matching of current vaccine strains against those viruses.Using phylogenetic and serological approaches we will identify viral strains conferring cross reaction against a wide range of strains within FMD virus serotypes and produce FMDV molecular vaccines using ARS Adenovirus technology. Sequence and serological R values of viral strains circulating in India were provided to ARS scientists. Phylogenetic analysis was performed with these data and viral strains genetically close to vaccine strains but with low R values were identified. Experiments were designed to confirm the R values and vaccine cross protection studies that will be carried out in India. Once conformed, P1-2A regions from these viruses will be used for cloning in Ad5 vectors to prepare experimental vaccines. This project was monitored through email and telephone exchange.