Prevalence of antibody to human T-cell lymphotropic virus type I in Okinawa, Japan, after an interval of 9 years.
To clarify events related to age dependence of human T-cell lymphotropic virus type I (HTLV-I) seroprevalence, the authors carried out two seroepidemiologic studies at a 9-year interval on residents of Yonaguni Island, Okinawa, Japan. The overall prevalence was 17.8% (345/1,943) in 1980 and 17.1% (264/1,543) in 1989-1990. The authors studied the relation of the HTLV-I infection rate to the birth year of 967 individuals tested in both years. Of the 967 individuals, 209 were positive for anti-HTLV-I in the 1980 survey. By the 1989-1990 survey, only 7 of the 758 anti-HTLV-I negative cases (0.9%) had become positive for anti-HTLV-I, and all 7 were over 40 years of age. For persons born in the same period, there was almost no difference between the prevalence of HTLV-I found in the 1980 survey and that found in the 1989-1990 survey. These data show that there were few new cases of HTLV-I infection and none in the lower age groups over the 9 years, which suggests that higher rates of HTLV-I infection in adults reflect past higher rates of infection as infants.
Morofuji-Hirata
M
M
Department of General Medicine, Kyushu University Hospital, Fukuoka, Japan.
Kajiyama
W
W
Nakashima
K
K
Noguchi
A
A
Hayashi
J
J
Kashiwagi
S
S
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015481:HTLV-I Antibodies / Q000097:blood*; D015490:HTLV-I Infections / Q000453:epidemiology*; D006801:Humans; D007223:Infant; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D016036:Seroepidemiologic Studies; D012737:Sex Factors
D015481:HTLV-I Antibodies