A18 HIV-2 molecular epidemiology in Spain: 30 years since the first case

Abstract

HIV-2 is a retrovirus that mainly infects West Africans. In Europe, HIV-2 has been circulating since the 1980s, and more recent immigration has contributed to its spread. Excluding HIV-2 in all HIV seropositive individuals precludes misinterpretation of viral loads (VL) and antiretroviral (ART) choices. Surveillance registers enables tracking of epidemic spread and identification of major contributors, allowing the establishment of convenient preventive measures. The HIV-2 Spanish study group was founded in 1989. Since then, blood specimens from HIV-2 carriers have been collected. More than 40 Spanish hospitals are part of the group and provide clinical and epidemiological data. Records for each HIV-2 patient include country of origin, gender, age, transmission category, monitoring of HIV-2 VL, CD4 counts, drug resistance, and HIV-2 subtype. Up to December 2017, 354 HIV-2+ individuals were identified in Spain and incidence (15–20/year) has been stable within the last decade. At diagnosis, mean age was 44.6 years and 63 per cent were male. The majority were Africans (78%), whereas 16.5 per cent were native Spaniards. 78.2 per cent acquired HIV-2 by heterosexual contact. HIV-2 subtyping using the HIV2EU tool was performed in 126 subjects: 86 Africans and 27 native Spaniards. The subtype distribution was as follows: 108 (85.7%) HIV-2 subtype A and 18 (14.3%) B. Africans and Spaniards were mostly infected with subtype A (87.2% and 77.8%, respectively). HIV-2 subtype B was found in six native Spaniards (22.2%; 6/27), five patients from Equatorial Guinea (71.4%; 5/7), four from Senegal (18.1%; 4/22), two from Ivory Coast (100%; 2/2), and one from Burkina Faso (50%; 1/2). Using phylogenetic analyses, two clusters were identified among homosexual Spanish men (subtype A: 8 men and subtype B: 2 men with viral isolates related to Malian and Senegalese isolates). Before starting ART, CD4 count mean values for subtype A and B were 378 and 357, respectively. Corresponding VL values were 2.63 and 2.32 HIV-2 RNA log copies/ml, respectively.