Background
The use of rapid tests for recent infection (RTRI) alongside CD4 as part of recent infection testing algorithm (RITA) has enabled identification of individuals who may have acquired HIV in the past 12 months (recent HIV infection). Measuring the risk for recent HIV infection is critical for effective public health interventions. We calculated the risk of recent HIV infection per 10,000 at-risk individuals and examined the distribution of recent HIV risk within specific populations.
Methods
Newly diagnosed persons living with HIV aged ≥15 years who were treatment-naïve or on treatment <30 days were offered recency testing using the Asante HIV-1 Rapid Recency Assay (Sedia Biosciences, Beaverton, OR, USA). Individuals with an Asante-recent result and baseline CD4>200 from case surveillance (CS) data were defined as RITA-CS recent. Routine HIV testing and RITA-CS recent infection data of individuals from 112 clinics in 9 provinces collected from October 2023 to March 2024 was extracted from the national HIV testing registry and the national surveillance of recent HIV infection database. We calculated the proportion of HIV-positives tested with RTRI and adjusted the number of HIV-negatives by the same proportion to calculate the at-risk population per 10,000 individuals (defined as HIV-negative and RITA-CS recent). We examined the variation of risk by age, sex, and population groups and used the Chi-squared test to detect any statistically significant differences (p<0.05).
Results
Of 152,673 individuals tested for HIV, 2,050 (1.3%) were diagnosed with HIV. Of these, 1,022 (49.9%) received an RTRI test and 60 (5.9%) were RITA-CS recent. RTRI testing coverage among newly HIV diagnosed was highest among MSM (86.9%), followed by PWID (80.0%) and 15–24year-olds (67.8%). The risk of recent HIV infection (Table) was highest among MSM (36.8 per 10,000), FSW (20.7 per 10,000), and 15-24 year-olds (14.1 per 10,000) and lowest among women (2.7 per 10,000) and the 50+ year-olds (2.8 per 10,000). Differences in proportion were observed for sex (p<0.01) and age group (p<0.01).
Conclusions
MSM and 15-24 years old had the highest risk of recent HIV infection. Focused prevention strategies for MSM and young men, enhanced surveillance, and further investigation into the behavioral and structural drivers of these disparities may reduce HIV transmission.