Prevalence of Human T Lymphotropic Virus Type 1 in Pregnant Women: a Narrative Review

Human T lymphotropic virus type I (HTLV-I) is a virus of the Retroviridae family, which has infected more than 20 million people around the world. The study aimed to review the prevalence of HTLV infection in pregnant women.     

We searched various databases including PubMed, EMBASE, Scopus, Google Scholar, SID, Magiran and Irandoc using the following keywords: HTLV-1, HTLV-2, Retroviridae, pregnancy, prevalence, incidence, women and female. Abstracts, short/brief reports as well as original and review articles published on HTLV-1 and/or HTLV-2 infection during pregnancy until October 2018 were included in the study.      

We found five articles from Iran and 14 articles from other parts of the world on the prevalence of HTLV-1 infection in pregnant women. Prevalence of HTLV-1 and or HTLV-2 was higher in pregnant women than in non-pregnant women in cities of Mashhad and Neyshabur, Razavi Khorasan Province (1.5 to 3.3 %), northeastern Iran, which are endemic areas of Iran for HTLV-1 infection. The incidence rate of HTLV-1 infection was 400-500 per 10,000 pregnant women in endemic areas of Japan. In Brazil, the rate of HTLV-1 infection in pregnant women was estimated to be 1.05%.

The prevalence of HTLV-1 varies among pregnant women depending on residence in endemic or non-endemic areas for HTLV-1. In endemic areas, it is recommended to perform routine screening for HTLV-1 infection in the general population, especially pregnant women.