New HIV Infections among Primigravida Mothers in Southern India: Analysis from HIV Sentinel Surveillance (2015-2021).

Background: HIV Sentinel Surveillance (HSS) among pregnant women aged 15-49 serves as a key indicator for estimating HIV infection rates in the general population. Primigravida mothers represent the broader female demographic for assessing new HIV infections and determining HIV incidence among the female general population, as HIV transmission is predominantly through heterosexual routes in India.

Objectives: This study aims to estimate the levels and trends of new infections among pregnant women in seven South Indian states and to understand the associated HIV risk factors.

Materials and methods: HSS data from pregnant women attending ANC across seven South Indian states in 2015, 2017, 2019, and 2021 were analyzed. Based on inclusion criteria, a total of 182,066 records were analyzed. Multivariate logistic regression was used to determine the correlation between sociodemographic factors and the occurrence of new HIV cases.

Results: A total of 470 (0.26%) new HIV infections were reported among all primigravida mothers, of which 74% ( n = 346) were aged between 15 and 24 years. Overall, the incidence among young primigravida mothers declined from 0.32% in 2015 to 0.20% in 2021. Age, education, and the occupation of the spouses were associated with the odds of new HIV infections Compared to 2019, the number of new HIV infections increased substantially in 2021 in the states of Andhra Pradesh, Karnataka, and Tamil Nadu, notably in 15-24-year age group.

Conclusions: There is a need to investigate the transmission patterns of new infections in the general population, taking into account the varying trends among different states.