RESUMO
OBJECTIVES: Blood donors in Canada have been tested for Human T-Cell Lymphotropic Virus (HTLV) since 1990. We report the epidemiology, risk factors and lookback/traceback of HTLV-positive donors/recipients. METHODS: The annual HTLV rate was calculated from 1990 to 2010. Residual risk was estimated as the product of incidence and window period. Twenty-nine HTLV-positive donors and 116 matched controls (ratio 1 : 4) were interviewed about risk factors. For HTLV-positive donations, lookback investigations involved identification of all previous donations, and attempting to locate and test recipients. Traceback was initiated when transfusion transmission was queried for HTLV-positive blood recipients. All donors of products that the recipient received were identified, with an attempt to locate and test them. RESULTS: The HTLV rate decreased from 9.35 per 100,000 donations in 1990 to 1.11 in 2010. The residual risk of infection was 1 in 7.6 million donations. In logistic regression birth overseas (OR 18.7), history of sexually transmitted diseases (OR 32.9), sex with unknown background (OR 5.4) and blood transfusion (OR 8.9) were significant predictors. In the lookback study, of 109 HTLV-positive donors, 508 components were transfused, of whom 147 recipients were tested and 18 (12%) were positive. All were transfused prior to the implementation of donor testing. Twenty-three traceback investigations were requested involving 324 transfused untested products,of whom 219 (67.6%) of donors were tested and 13 (6%) were positive for HTLV. CONCLUSIONS: With testing of the blood supply, the risk from HTLV is very low and while most HTLV-positive donors have risk factors, deferrable risk is rare.
Assuntos
Infecções por HTLV-I/epidemiologia , Infecções por HTLV-II/epidemiologia , Vírus Linfotrópico T Tipo 1 Humano , Vírus Linfotrópico T Tipo 2 Humano , Adolescente , Adulto , Doadores de Sangue , Transfusão de Sangue , Canadá/epidemiologia , Seleção do Doador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de RiscoRESUMO
The prevalence of HIV-1 antibodies in selected groups of individuals from Rio de Janeiro, São Paulo and Santos was determined retrospectively. These groups and respective prevalences were: hemophiliac patients from Rio de Janeiro (1983-1984) 98.0%; polytransfused hemodialysis patients from São Paulo (1985-1986) 3.0% and (1987) 7.7%; intravenous drug addicts from São Paulo and Rio de Janeiro (1986-1987) 15.9%; male prisoners from São Paulo (1988) 12.5%, and pregnant women from Santos (1988-1989) 3.6%. These data stress the magnitude of AIDS in Brazil.
