doi:10.3389/fimmu.2023.1277793deuAyerdi, OskarBenito, RafaelOrtega, DiegoAguilera, AntonioMontiel, NataliaPintos, IlduaraDíaz de Santiago, AlbertoBaza, BegoñaSoriano, Vicentede Mendoza, CarmenHTLV infection in persons with sexually transmitted diseases in SpainART-2023-137164Background: HTLV-1 infection is a neglected disease, despite estimates of 10 million people infected worldwide and producing life-threatening illnesses in 10% of carriers. Sexual transmission is the main route of contagion. However, HTLV-1 is not listed among sexually transmitted infections (STIs). Methods: Serum from all consecutive individuals who had attended six STI clinics across Spain during the last 12 months were tested for HTLV antibodies using a commercial enzyme immunoassay (EIA). Reactive samples were confirmed by immunoblot. Results: A total of 2,524 samples were examined. The majority (1,936; 76.7%) belonged to men, of whom 676 (34.9%) were men who have sex with men (MSM) receiving HIV pre-exposure prophylaxis. Although native Spaniards predominated (1,470; 58.2%), up to 593 (23.5%) came from Latin America and 139 (5.5%) were African. A total of 26 individuals were initially EIA reactive and immunoblot confirmed 5 as HTLV-1 and 7 as HTLV-2. All but one HTLV-1+ case came from Latin America. Three were men and two were women. Among Latin Americans, the HTLV-1 seroprevalence was 0.67%. In contrast, all seven HTLV-2+ were native Spaniards and former injection drug users, and all but one were HIV+. Conclusion: The rate of HTLV infection among individuals with STIs in Spain is 0.5%, which is greater than in the general population. These results support the introduction of universal HTLV screening in persons who attend clinics for STIs.2023http://zaguan.unizar.es/record/13179910.3389/fimmu.2023.1277793http://zaguan.unizar.es/record/131799oai:zaguan.unizar.es:131799info:eu-repo/grantAgreement/ES/ISCIII/FIS/PI21-1717Frontiers in Immunology 14 (2023), 1277793 [6 pp.]byhttp://creativecommons.org/licenses/by/3.0/es/info:eu-repo/semantics/openAccess