SYMPTOM:
      Footmouth disease (FMD) is a highly infectious viral infection of cattle, pigs, sheep, goats, buffalo, artiodactyl wildlife species. It is characterized by fever vesicles in the mouth on the muzzle, teats, feet death in young animals. All species of deer antelope, elephant, giraffe are susceptible to FMD, but camels are resistant to natural infection, the smaller camelids such as alpacas llamas, although susceptible, are probably of no epidemiological significance. Camels, mice, guinea pigs can be infected experimentally

Etiology:
      FMD is caused by an aphthovirus of the family Picornaviridae. There are seven immunologically distinct serotypes: A, O, C, Asia 1, SAT (Southern African Territories) 1, 2, 3. Within each serotype, there is a large number of strains that exhibit a spectrum of antigenic characteristics therefore, a number of vaccine strains for each serotype, particularly O A, are required to cover the antigenic diversity. Strains are characterized by their genomic relationships their antigenic similarities with established vaccine strains. (Previous classification into subtypes became untenable as the number of subtypes rapidly increased.)

Clinical Findings:
        The incubation period for FMD is 2-14 days, depending on the infecting dose, susceptibility of the host, strain of virus. The clinical signs are more severe in dairy cows intensively reared pigs than in sheep goats, FMD has frequently been ignored or misdiagnosed in small ruminants. After the incubation period, a fever of up to 107°F (41.5°C) develops, the animal is anorexic salivates stamps its feet as vesicles develop on the tongue, dental pad, gums, lips, on the coronary b interdigital cleft of the feet. Vesicles may also appear on the teats udder, particularly of lactating cows sows, on areas of skin subject to pressure trauma, such as the legs of pigs. Young calves, lambs, kids, piglets may die before showing any vesicles because of virus-induced damage to the developing cells of the myocardium. Milk yield s dramatically in milking animals, all animals show a loss in condition growth rate that may persist after recovery. Sheep goats may develop only a few vesicles on the coronary b in the mouth. Vesicles in the mouth, even when severe, usually heal within 7 days, although recovery of the tongue papillae takes longer. Lesions on the mammary gl feet frequently develop secondary infections, resulting in mastitis, underrunning of the sole, chronic lameness. In pigs, the complete horn of the toe may be lost. Cattle deer may also lose one or both horns of the foot.

PREVENTION:
       The occurrence of FMD in countries previously free of the disease can have a major effect on local international trading arrangements. Many countries free of FMD have a policy of slaughter of all affected in-contact susceptible animals strict restrictions on movement of animals vehicles around infected premises. After slaughter, the carcasses are either burned or buried on or close to the premises, the buildings are thoroughly washed disinfected with mild acid or alkali by fumigation. Tracing is carried out to identify the source of the outbreak premises to which FMD virus could have already been transmitted by infected animals or animal products, contaminated vehicles or people, or aerosol. In areas or countries free of FMD in which this is not possible, control is by movement restriction, quarantine of affected premises, vaccination around ( possibly within) the affected premises. This has the disadvantage that many carrier animals may remain after the outbreak, quarantine may not be sufficiently long to prevent their subsequent movement. In countries in which FMD is endemic, protection, particularly of high-yielding dairy cattle, is by a combination of vaccination prevention of FMD virus entering the dairy premises. This can be difficult if prevalence of FMD in the unvaccinated population is high climatic conditions are suitable for aerosol transmission of the virus. FMD vaccine is a killed preparation , at best, affords good protection against challenge for 4-6 mo. However, the antigenic diversity of strains of FMD virus within each of the serotypes is an additional complication, so it is necessary to ensure that vaccines contain strains antigenically similar to the potential outbreak strains. Otherwise, the duration of immunity provided by vaccines containing dissimilar strains may be very short. FMD vaccines for pigs require an oil adjuvant, whereas those for ruminants may contain an oil or aluminium hydroxide/saponin adjuvant. There are currently no alternatives to vaccine antigens derived from whole virus grown in tissue culture then chemically inactivated.