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World Distribution FMD
Serotypes
Susceptibility
Molecular Epidemiology
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Serotype O is the most widely distributed, being endemic
in many South American, African and Asian countries, affecting all susceptible
species. It has caused recent outbreaks in Italy (1993), Greece (1994
and 1996), Bulgaria (1991, 1993 and 1996), Georgia (1997), Armenia (1996)
and the southern republics of the former Soviet Union, Taiwan (1997),
Russia (1995) and Philippines (major outbreaks in 1996). Certain strains
of serotype O appear particularly adapted to a particular host species.
Within serotype O there are groups of strains (genotypes) which are associated
with particular areas of distribution, and species preference. The Middle
East type O is well adapted to sheep and cattle (possibly due to the small
number of pigs in the region), whereas the Far East type O is responsible
for the major outbreaks in pigs in that region. In areas where there are
outbreaks in pigs and cattle (e.g., Vietnam), the strains causing disease
in each species are easily distinguishable by nucleotide sequencing.
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