Diagnosis and case finding according to key partner risk populations of people living with HIV in Nigeria: A retrospective analysis of community-led index partner testing services.

Background: The HIV epidemic in Nigeria is concentrated in Key Populations (KP), people who inject drugs (PWID), men who have sex with men (MSM), female sex workers (FSW), and partners of people living with HIV. Due to stigma and discrimination, these groups have low access to HIV testing services (HTS) and linkage to treatment is challenging. To address this gap, index partner testing, targeting sexual contacts and injecting partners of KP index clients, was introduced in 2017.

Methods: The study was a retrospective analysis of community-led HIV index partner testing-involving review of secondary data from partner notification services registers. Between October 1, 2018, and September 30, 2019, HIV testing as part of index partner testing services was offered at nightclubs, hotels, and community-based ART clinics in the states of Akwa Ibom, Cross River, and Lagos. Index testing was assisted by peer navigators. We used provider and passive Partner Notification (PN) methods. In-person and social network methods were used to recruit partners of KP. We described the implementation of index partner testing services as part of the national KP program, analyzed PN delivery models, and calculated HIV seropositivity among persons who underwent Index Partner Testing. One-Way ANOVA and Tukey-HSD test were performed to determine whether the differences in mean HIV seropositivity between partners are statistically significant.

Findings: PN was predominantly done through provider referral 5,159 (68.3%) and passive/client referral 2,278 (30.1%). A total of 3,119 index partners; 1,322 FSW (42.4%), 1,255 MSM (40.2%) and 542 PWID (17.4%) identified 8,989 sexual and injecting partners (index partner ratio 1:2.9). Among the partners, 7,556 (84.1%) were first-time testers, and 79.4% (5,999) of male partners tested. Of the 3,753 (49.7%) partners who tested HIV-positive, 3,492 (93.0%) were enrolled in HIV care. HIV seropositivity rate was 65.5% (1,021/1,557) among females and 45.5% (2,732/5,999) among males and was disproportionately higher among PWID injecting partners 99.1% (581/586), PWID sexual partners 98.9% (433/438) and MSM sexual partners 95.6% (605/633) in Cross river compared with 71.4% (575/805) in FSW sexual partners.

Interpretations: Including index partner testing as part of a community-led HTS can help improve HIV case-finding approach for KP, particularly for reaching first-time testers, male KP, and persons not yet diagnosed with HIV. Scale-up of index partner testing within community-led HTS is essential for achieving the United Nations 95-95-95 goals.

Funding: This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.