RESUMEN
Anti-HIV 1 antibodies were detected in 4 groups of subjects (peoples attending hospitals or medical clinics for anti-HIV investigation, blood donors, women in massage parlours and thalassemia patients) in the north, northeast and central Thailand. A total number of 1,726 blood samples were initially tested with ELISA. The ELISA reactive samples were confirmed by the Western blot analysis. Using ELISA as a screening test, the highest incidence (9.09%) of anti-HIV 1 antibodies was found in thalassemic children (4 of 44). Six (0.72%) and 4 (1.02%) samples in the first, second and third groups had a repeatedly reactive ELISA respectively. The Western blot analysis confirmed that 7 cases (3 thalassemia and 4 subjects in the first group) had antibodies to HIV 1. Two cases with reactive Western blot test were Westerners while the rest were symptomatic and asymptomatic Thais. The HIV infection has spread to thalassemia patients probably via blood transfusion.