Knowledge and risk practices related to HIV infection in the general population, young men, and MSM in three Brazilian cities in 2019.

The study aimed to describe knowledge and risk practices related to HIV infection in three Brazilian cities in the general population, men 15 to 24 years of age living without a partner, and men that reported sex with other men (MSM) at least once in life. This was a cross-sectional household-based study with three-stage cluster sampling (census tracts, households, individuals) stratified by sex, age group (15-24; 25-34; 35-44; 45-59), and conjugal status in the individual selection. We estimated the proportions and 95% confidence intervals (95%CI) of indicators of knowledge, HIV testing, sexual behavior, and self-rated risk. We analyzed 5,764 individuals in Campo Grande, 3,745 in Curitiba, and 3,900 in Florianópolis. Low levels of knowledge were found for preventive methods, especially PrEP. Unprotected sex practices were frequent in the three municipalities. Lifetime HIV test rates were 57.2% (95%CI: 55.1-59.2) in Curitiba, 64.3% (95%CI: 62.7-66.0) in Campo Grande, and 65.9% (95%CI: 64.0-67.7) in Florianópolis. Among men 15-24 years of age, the proportions of stimulant drug use and unprotected sexual practices were higher than in the other age groups. Lifetime HIV test rates exceeded 80% in MSM. More than 30% of MSM were receptive partners in anal sex without condoms, and fewer than 5% assessed their risk as high. More effective communication strategies are needed on prevention of HIV infection, including increased knowledge that could motivate safer sexual practices.