Information about the distribution of bluetongue in Turkey during 1978
-81 has been obtained by serological surveys in cattle, sheep and goat
s. The group-specific immunodiffusion test was used to identify the pr
esence of bluetongue virus (BTV) in a given province and the type-spec
ific microneutralization test to decide which virus types had been in
circulation. By drawing sera from accurately aged donor animals in May
and August 1980, it was possible to draw up a general outline of the
distribution of BTV in Turkey between early 1978 and mid 1980. By comb
ining the same technique with spring and autumn held visits it became
possible to make detailed inferences about the distribution of BTV ser
otypes in 1980 and 1981. The results support the conclusion that BTV w
as widespread in central and western Turkey for a number of years and
suggests that overwintering can be a regular occurrence in that countr
y. When compared with contemporaneous results from Syria and Jordan, a
unifying and well-defined bluetongue virus ecosystem becomes apparent
.