Quality and effectiveness of index testing among individuals with recent HIV infection in Vietnam

BACKGROUND: HIV viral burden is the primary predictor of HIV morbidity, mortality, and transmission. Recently infected individuals are likely members of active HIV transmission networks. Therefore, facilitating voluntary participation in index testing among these individuals is an epidemic control priority. This analysis compares index testing performance among index clients with confirmed recent HIV infection and chronic HIV infection in Dong Nai, Tay Ninh, and Tien Giang provinces.
METHODS: We reviewed program data among all newly diagnosed HIV-positive individuals in three provinces from October 2019 to September 2020. Data on index testing at public health facilities were extracted from DieuTriARV.vn, and data on index testing in the community from the Reach 4.0 platform, both health information systems developed by the USAID/PEPFAR-funded USAID SHIFT project. We applied t-test and chi-square test to assess potential significant differences between recently and chronically infected clients at points along the index testing cascade.
RESULTS: Among 1,637 newly diagnosed with HIV, 1,117 (68.2%) were tested for recent HIV infection. Among those, 90 (8.1%) had confirmed recent infection and 1,027 (91.9%) had chronic infection. We found no significant difference in index testing acceptance rates between the two (45% and 42%; 95% confidence level [CL]; p=0.562). Clients with recent HIV infection provided fewer contacts on average (2.5 contacts per recent vs. 3.3 contacts per chronic; 95% CL; p=0.046). There was no difference found between number of contacts tested. The proportion of tested contacts who were newly diagnosed with HIV was higher among recently infected index clients (23.6%) than among chronically infected clients (19.1%), but it was not statistically significant (95% CL: p =0.338).
CONCLUSIONS: Given the epidemiological significance, programs should ensure no missed opportunities to offer and support participation in voluntary, ethical index testing among recently infected individuals. We found no significant difference in index testing acceptance between recently and chronically infected individuals, but participation in both groups was low, though chronically infected individuals named more contacts on average. Both of these factors could contribute to our finding no significant difference in case-finding between the two groups, pointing to opportunities to strengthen client-centered index testing approaches to improve performance.