BURDEN AND SEVERITY OF COVID-19 IN CHILDREN HOSPITALISED OVER FIVE COVID-19 WAVES IN SOWETO, SOUTH AFRICA

INTRO: There is sparse data on SARS-CoV-2 infection among paediatric patients from low-middle income countries (LMICs), including from sub-Saharan Africa. We describe the burden and severity of disease in children treated with SARS- CoV-2 infection at an academic hospital in Soweto, South Africa from 30 March 2020 through 30 June 2022. METHODS: SARS-CoV-2 was detected using reverse transcriptase polymerase chain reaction (RT-PCR) of nasopharyngeal swab specimens. Clinical diagnoses, HIV status, admission C-reactive protein (CRP), blood culture results and clinical outcomes were captured. Epidemic waves were designated as follows: Wave 1 (01 March to 14 October 2020); Wave 2 (15 October 2020 to 17 May 2021); Wave 3 (18 May to 14 November 2021); Wave 4 (15 November 2021 to 14 March 2022); Wave 5 (15 March to 30 June 2022). FINDINGS: There were 797 SARS-CoV-2 positive paediatric hospitalisations in the study period. SARS-CoV-2 detection prevalence was 4.6% (77/1,673) in Wave 1, 3.9% (134/3,426) in Wave 2, 7.1% (187/2,618) in Wave 3, 12.5% (261/2,088) in Wave 4 and 5.9% (138/2,320) in Wave 5. Among SARS-CoV-2 positive cases, the prevalence of respiratory admission diagnoses increased over time (16.9% in Wave 1 to 42.8% in Wave 5). Conversely, the prevalence of multisystem inflammatory syndrom of childhood (MIS-C) and case fatailty ratios (CFRs) declined from Wave 1 to Wave 5 (MIS-C: 20.8% to 2.2%; CFR: 9.1% to 3.6%). Death was significantly associated with younger age (median age 3.4 versus 16.9 months), positive admission blood cultures (24.0% versus 8.4%), MIS-C (20.7% versus 6.5%), and HIV infection (21.1% versus 4.5%). CONCLUSION: The omicron dominated fourth and fifth waves of SARS-CoV-2 infection were associated with a higher prevalence of respiratory admission diagnoses, but lower case fatality compared to the ancestral first wave in South African children. Optimisation of antenatal maternal SARS-CoV-2 vaccination and early HIV diagnosis may impact on paediatric SARS-CoV-2 CFR.