Performance of rapid antigen tests in identifying Omicron BA.4 and BA.5 infections in South Africa.

BACKGROUND: Concerns around accuracy and performance of rapid antigen tests continue to be raised with the emergence of new SARS-CoV-2 variants. OBJECTIVE: To evaluate the performance of two widely used SARS-CoV-2 rapid antigen tests during BA.4/BA.5 SARS-CoV-2 wave in South Africa (May - June 2022). STUDY DESIGN: A prospective field evaluation compared the SARS-CoV-2 Antigen Rapid test from Hangzhou AllTest Biotech (nasal swab) and the Standard Q COVID-19 Rapid Antigen test from SD Biosensor (nasopharyngeal swab) to the Abbott RealTime SARS-CoV-2 assay (nasopharyngeal swab) on samples collected from 540 study participants. RESULTS: Overall 28.52% (154/540) were SARS-CoV-2 RT-PCR positive with median cycle number value of 12.30 (IQR 9.30-19.40). Out of the 99 successfully sequenced SARS-CoV-2 positive samples, 18 were classified as BA.4 and 56 were classified as BA.5. The overall sensitivities of the AllTest SARS-CoV-2 Ag test and Standard Q COVID-19 Ag test were 73.38% (95% CI 65.89-79.73) and 74.03% (95% CI 66.58-80.31) and their specificities were 97.41% (95% CI 95.30-98.59) and 99.22% (95% CI 97.74-99.74) respectively. Sensitivity was >90% when the cycle number value was <20. The sensitivity of both rapid tests was >90% in samples infected with Omicron sub-lineage BA.4 and BA.5. CONCLUSION: Accuracy of tested rapid antigen tests that target the nucleocapsid SARS-CoV-2 protein, were not adversely affected by BA.4 and BA.5 Omicron sub-variants.

Impact of COVID-19 public health responses on income, food security and health services among key and vulnerable women in South Africa.

Globally, COVID-19 has impacted lives and livelihoods. Women living with HIV and/or at high risk of acquiring HIV are socially and economically vulnerable. Less is known of the impact of COVID-19 public health responses on women from key and vulnerable populations. The purpose of this cross-sectional survey conducted in four South African provinces with a high burden of HIV and COVID-19 from September to November 2021 was to advance understanding of the socio-economic and health care access impact of COVID-19 on women living with HIV or at high risk of acquiring HIV. A total of 2 812 women >15 years old completed the survey. Approximately 31% reported a decrease in income since the start of the pandemic, and 43% an increase in food insecurity. Among those accessing health services, 37% and 36% reported that COVID-19 had impacted their access to HIV and family planning services respectively. Economic and service disruptions were enhanced by living in informal housing, urbanisation and being in the Western Cape. Food insecurity was increased by being a migrant, having fewer people contributing to the household, having children and experience of gender-based violence. Family planning service disruptions were greater for sex workers and having fewer people contributing to the household. These differentiated impacts on income, food security, access to HIV and family planning services were mediated by age, housing, social cohesion, employment and household income, highlighting the need for improved structural and systemic interventions to reduce the vulnerability of women living with HIV or at high risk of acquiring HIV.

Clinical Evaluation of Severe Acute Respiratory Syndrome Coronavirus 2 Rapid Antigen Tests During the Omicron Wave in South Africa.

We evaluated the performance of nasal and nasopharyngeal Standard Q COVID-19 [coronavirus disease 2019] Ag tests (SD Biosensor) and the Panbio COVID-19 Ag Rapid Test Device (nasal; Abbott) against the Abbott RealTime severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) assay during the Omicron (clades 21M, 21K, and 21L) wave in South Africa. Overall, all evaluated tests performed well, with high sensitivity (range, 77.78%-81.42%) and excellent specificity values (>99%). The sensitivity of rapid antigen tests increased above 90% in samples with cycle threshold <20, and all 3 tests performed best within the first week after symptom onset.

The impact of the COVID-19 lockdown on HIV care in 65 South African primary care clinics: an interrupted time series analysis.

BACKGROUND: The effect of the COVID-19 pandemic on HIV outcomes in low-income and middle-income countries is poorly described. We aimed to measure the impact of the 2020 national COVID-19 lockdown on HIV testing and treatment in KwaZulu-Natal, South Africa, where 1·7 million people are living with HIV. METHODS: In this interrupted time series analysis, we analysed anonymised programmatic data from 65 primary care clinics in KwaZulu-Natal province, South Africa. We included data from people testing for HIV, initiating antiretroviral therapy (ART), and collecting ART at participating clinics during the study period, with no age restrictions. We used descriptive statistics to summarise demographic and clinical data, and present crude summaries of the main outcomes of numbers of HIV tests per month, ART initiations per week, and ART collection visits per week, before and after the national lockdown that began on March 27, 2020. We used Poisson segmented regression models to estimate the immediate impact of the lockdown on these outcomes, as well as post-lockdown trends. FINDINGS: Between Jan 1, 2018, and July 31, 2020, we recorded 1 315 439 HIV tests. Between Jan 1, 2018, and June 15, 2020, we recorded 71 142 ART initiations and 2 319 992 ART collection visits. We recorded a median of 41 926 HIV tests per month before lockdown (January, 2018, to March, 2020; IQR 37 838-51 069) and a median of 38 911 HIV tests per month after lockdown (April, 2020, to July, 2020; IQR 32 699-42 756). In the Poisson regression model, taking into account long-term trends, lockdown was associated with an estimated 47·6% decrease in HIV testing in April, 2020 (incidence rate ratio [IRR] 0·524, 95% CI 0·446-0·615). ART initiations decreased from a median of 571 per week before lockdown (IQR 498-678), to 375 per week after lockdown (331-399), with an estimated 46·2% decrease in the Poisson regression model in the first week of lockdown (March 30, 2020, to April 5, 2020; IRR 0·538, 0·459-0·630). There was no marked change in the number of ART collection visits (median 18 519 visits per week before lockdown [IQR 17 074-19 922] vs 17 863 visits per week after lockdown [17 509-18 995]; estimated effect in the first week of lockdown IRR 0·932, 95% CI 0·794-1·093). As restrictions eased, HIV testing and ART initiations gradually improved towards pre-lockdown levels (slope change 1·183/month, 95% CI 1·113-1·256 for HIV testing; 1·156/month, 1·085-1·230 for ART initiations). INTERPRETATION: ART provision was generally maintained during the 2020 COVID-19 lockdown, but HIV testing and ART initiations were heavily impacted. Strategies to increase testing and treatment initiation should be implemented. FUNDING: Wellcome Trust, Africa Oxford Initiative.