Integrating point-of-care screening for curable sexually transmitted infections with HIV, syphilis and hepatitis B screening in antenatal care services in Zimbabwe: a mixed-methods process evaluation

Abstract

Introduction: Sexually transmitted infections (STIs) in pregnancy are associated with adverse birth outcomes. We investigated the uptake and yield of point-of-care screening for Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis, integrated with HIV, syphilis and hepatitis B virus (HBV) screening in antenatal care (ANC) in Zimbabwe, and conducted a mixed-methods process evaluation of the strategy.

Methods: A prospective interventional study was conducted in two public-sector ANC clinics in Harare. Clients attending for ANC were screened in parallel for C. trachomatis, N. gonorrhoeae, T. vaginalis, HBV, HIV and syphilis, using four different point-of-care tests. Uptake of STI testing and treatment was recorded. Interviews and focus group discussions with pregnant women, healthcare professionals and the intervention team were conducted and analysed thematically. Implementation, mechanisms of impact and context were explored using the Medical Research Council Process Evaluation Framework.

Results: Between 12 January 2023 and 23 October 2023, there were 13 500 ANC attendances over 207 implementation days. Of 1105 (8.2%) assessed for eligibility, 1103 (99.8%) were eligible, of whom uptake of the full screening package was 91.0% (1004/1103). Curable STI prevalence was 30.7% (308/1003), of whom 303 (98.4%) received same-day treatment. HBV prevalence was 1.4% (14/1003). The prevalence of HIV was 10.5% (105/1003), with 20 (19.0%) being new diagnoses.Although the intervention was highly acceptable, diagnostic capacity and workload were barriers to recruitment. In particular, the collection and testing of multiple sample types with different tests, with a range of reading times, was challenging.

Conclusion: We demonstrated high levels of acceptability, screening uptake and same-day treatment. However, a low proportion of ANC attendees were enrolled overall, and current technological limitations preclude this particular testing strategy from being scaled up beyond low-volume settings. We recommend investment into the development of STI point-of-care tests with shorter analytic times and research into alternative strategies involving laboratory-based high-throughput testing.

Trial registration number: ClinicalTrials.gov NCT05541081; registered 15 September 2022.

Keywords: Global Health; Health services research; Maternal health; Screening; Zimbabwe.

Figure 1. Testing cascade for curable sexually transmitted infections. ANC, antenatal care; CRF, case report form; CT, Chlamydia trachomatis; NG, Neisseria gonorrhoeae; TV, Trichomonas vaginalis.