RESUMEN

INTRODUCTION: Human T-cell lymphotropic virus (HTLV-I) is the causative agent for adult T-cell lymphoma/leukemia (ATLL) and HTLV-I-associated myelopathy/tropical spastic paraparesis. The virus is endemic in the parts of Iran. This study is conducted to determine the trends in the frequency of HTLV-I in Mashhad, a city in Khorasan-e Razavi province, Iran, over 11 years. MATERIALS AND METHODS: Blood bank records of blood donors positive for HTLV-I were collected from different blood banks across Mashhad between 2002 and 2013. Obtained data were first entered into paper versions and then were analyzed by SPSS version 11.5. HTLV-I antibody was firstly measured by enzyme-linked immunosorbent assay (ELISA) method and later confirmed by the Western Blot (WB). RESULTS: During the study period, 983,000 donors were examined by ELISA and WB, among whom 2921 cases (0.297%) were positive HTLV-I carriers. The highest and lowest frequency of carriers was 0.451% and 0.098%, respectively. The most significant factor was related to marital status (85.2%) and the smallest significant factor was associated with the history of acupuncture (0.3%) according to the different risk factors. CONCLUSION: The frequency of HTLV-I carriers among blood donors was significantly decreased in this period. Screening of blood donors for HTLV-I infection played a significant role in this reduction.