Abstract
Intestinal protozoa are a common cause of morbidity in people living with HIV (PWH), particularly in tropical regions with poor sanitation. We conducted a cross-sectional study in 315 PWH from Iquitos, Peru, between October 2023 and May 2024, to assess their prevalence and risk factors. Stool samples were examined using Lugol's iodine, modified Ziehl-Neelsen (MZN) staining, and immunochromatography (ICT). The mean age was 41 years, with a median CD4+ count of 431 cells/µL; 12.4% were in the AIDS stage, and 21.5% had a detectable viral load. 51.4% of the participants tested positive for any intestinal protozoa. The overall Cryptosporidium spp. prevalence (by combining MZN and ICT results) was 25.7%. The overall Giardia spp. and Entamoeba spp. prevalences (by combining Lugol's iodine and ICT results) were 2.9% and 1.9%, respectively. Blastocystis spp. was frequently isolated, though its pathogenicity remains uncertain. Diagnostic agreement was almost perfect between Lugol and ICT for Giardia and Entamoeba (κ = 0.87; p < 0.001 and κ = 0.91; p < 0.001, respectively), but only slight between MZN and ICT. Homosexual practices were identified as a significant risk factor for pathogenic protozoa infection (AOR 2.52; 95% CI: 1.04-6.12). In conclusion, the high prevalence of protozoa infection reflects ongoing fecal-oral exposure, underscoring the need for public health education, routine diagnosis, and treatment in similar settings.