K. Ishibashi et al., SEROPREVALENCE SURVEY OF AINO VIRUS-INFECTION IN DAIRY-CATTLE OF FUKUOKA, JAPAN IN 1990, Journal of veterinary medical science, 57(1), 1995, pp. 1-4
The seroprevalence and seroconversion to Aino virus infection were epi
demiologically analyzed in Fukuoka Prefecture, by a cohort study, in 1
990. Serum samples (872) were taken from 436 cattle of 128 farms in fi
ve different districts at twice sampling with four month-intervals and
were tested by a serum neutralizing test with Aino virus. In the firs
t sampling (May-July), 38.3% of sera and 40.6% of farms tested were po
sitive and 33.3% of cattle and 40.6% of farms were sere-converted duri
ng the period of September-November in 1990. Significant differences w
ere found in seroprevalence of farms and seroconversion of cattle/farm
s among five districts; there was, however, a highly significant corre
lation between seroprevalence and seroconversion of farm. Consequently
, five districts of Fukuoka Prefecture were classified into four epide
mic areas according to seroprevalence and seroconversion factors of a
principal component analysis.