Integrating SARS-CoV-2 rapid antigen testing in maternal, neonatal and child health, HIV and tuberculosis services in Cameroon and Kenya: a cluster randomised trial of two testing models.

INTRODUCTION

Identifying SARS-CoV-2 infection in high-risk populations is critical. We examined SARS-CoV-2 case detection (CD) in 'TA' versus 'screen-and-test' models of rapid antigen testing integration in maternal neonatal and child health (MNCH), HIV and tuberculosis (TB) clinics in Cameroon (C) and Kenya (K).

METHODS

From May to October 2022, we conducted a cluster-randomised trial with 10 facilities per country randomised to the 'test-all' (TA) intervention arm or the standard 'screen-and-test' (ST) arm. Individuals aged >2 years attending HIV, TB and MNCH clinics were eligible for SARS-CoV-2 testing. The primary outcome was the SARS-CoV-2 CD, defined as the number of SARS-CoV-2 infections detected per 1 000 attendees in MNCH, HIV and TB clinics. We estimated the intervention arm-specific CDs by combining the facility-specific estimates using a weighted approach.

RESULTS

There were 80 828 attendee visits in the TA model (63 492 C, 17 336 K) and 71 254 in the ST model (56 589 C, 14 665 K). About 17.4% (K) and 29.0% (C) were tested under the TA model. The overall CD was 2.90 (95% CI:1.76 to 4.79) per 1 000 attendee visits in the TA model and 1.20 (95% CI:0.73 to 1.99) in the ST model (RR=2.41, 95% CI:1.18 to 4.91, p=0.018). The TA model had a significantly higher SARS-CoV-2 CD in MNCH clinics (2.91 vs 1.11, p=0.012), while CD estimates in HIV (2.88 vs 1.40, p=0.203) and TB (10.24 vs 4.57, p=0.051) clinics, although higher in TA model compared with ST model, were not statistically different.

CONCLUSIONS

The TA model identified more SARS-CoV-2 cases than the screen-and-test model, even with low testing coverage. The TA model could be considered in future epidemics for early detection of SARS-CoV-2 infection among vulnerable populations, but effective implementation requires additional human resources to manage testing in high volume clinics.

TRIAL REGISTRATION NUMBER: NCT05382130.