Figure 1:

Top panel: Percentage testing real-time reverse transcription polymerase chain reaction (rRT-PCR)-positive per study visit and cumulative percentage with evidence of infection (attack rate) on serology only and on rRT-PCR and serology combined, a rural site and an urban site, South Africa, 2020–2021. Middle panel: Results of serology and rRT-PCR of individuals enrolled in the PHIRST-C study, a rural site and an urban site, South Africa, 2020–2021. Columns are individual follow up visits and rows are individual participants. Individuals within the same household are numbered consecutively (appear below one another). Follow up visits are coloured white if no sample was tested, light pink if the sample tested negative for SARS-CoV-2 and coloured red if the nasopharyngeal swab tested positive for SARS-CoV-2. Cells at the time of serology blood draws are coloured according to the results of serology as follows: light blue - serology negative, dark blue - serology positive. Bottom panel: Percent of rRT-PCR-positive samples typed as wild type (WT) or variant of concern (Alpha, Beta or Delta) by follow-up visit (10 visit moving average used for smoothing).