"Figure 5: Percentage of primary and secondary school staff testing positive for SARS-CoV-2 antibodies","" "England, 3 to 20 November 2020 (Round 1), 30 November to 11 December 2020 (Round 2), 15 to 31 March 2021 (Round 4), 5 to 21 May 2021 (Round 5) and 14 June to 6 July 2021 (Round 6)","" "","" "Notes","1. To ensure consistent comparisons between rounds, only the 11 local authorities with coverage in all rounds and for at least two primary and two secondary schools in the sample are included in the total figures provided. These are not necessarily the same schools or participants tested between rounds. " "Unit","%" "","" " "," % positive for current infection","Lower 95% confidence interval","Upper 95% confidence interval" "Primary school staff - Round 1","12.63","9.74","16.00" "Primary school staff - Round 2","14.61","11.86","17.72" "Primary school staff - Round 4","24.95","21.07","29.15" "Primary school staff - Round 5","26.67","22.43","31.25" "Primary school staff - Round 6","30.01","24.58","35.90" "Secondary school staff - Round 1","12.27","10.58","14.13" "Secondary school staff - Round 2","15.72","14.01","17.55" "Secondary school staff - Round 4","22.72","20.31","25.27" "Secondary school staff - Round 5","24.67","21.82","27.70" "Secondary school staff - Round 6","27.55","24.28","31.00"