The following points relate to school staff working in state-funded primary and secondary schools in England.
There was a higher percentage of primary school staff with a positive coronavirus (COVID-19) test than secondary school staff across both the autumn 2021 and spring 2022 terms; staff in both school types saw an increase in the percentage with a positive test in the spring 2022 term compared with autumn 2021.
Changes to the testing guidance in the second half of the spring 2022 term mean that it is likely that a lower proportion of infections were recorded in the NHS Test and Trace data, underestimating the increase in infections between the two terms.
Both primary and secondary school staff aged under 25 years or aged 60 years and over had lower percentages with a positive test compared with those of other ages in both the autumn 2021 and spring 2022 terms.
COVID-19 vaccine uptake in school staff is higher than that seen in the wider adult population of the same age range; this applies to those who have received second or third doses of a vaccine.
There was variation in vaccine uptake between ethnic groups; Chinese, Indian, and White British staff had the highest percentages of those who had received at least two or more doses.
Staff who received a third dose of the vaccine before the start of the spring 2022 term were less likely to have a positive test, when compared with those who had two doses.
The coronavirus (COVID-19) case data presented in this article are produced by linking the School Workforce Census (SWC) to NHS Test and Trace data and the National Immunisation Management Service (NIMS) dataset.
The linked data cover all school workforce staff working in state-funded schools in England only (including special schools). The data available from the SWC relate to the school workforce employed in the previous academic year, some of whom may no longer be employed in state-funded schools.
This article focuses on the two most recent school terms; autumn 2021 (31 August to 22 December 2021, Delta dominant) and spring 2022 (3 January to 6 April 2022, Omicron dominant). It aims to understand how the proportions of staff testing positive for COVID-19, and the characteristics of these staff, changed over time.
Changes to the testing guidance in the second half of the spring 2022 term mean that it is likely that a lower proportion of infections were recorded in the NHS Test and Trace data. See Section 16: Data sources and quality.
Data by term for the previous 2020 to 2021 academic year are also available in the accompanying dataset.Back to table of contents
A confidence interval gives an indication of the degree of uncertainty of an estimate, showing the precision of a sample estimate. The 95% confidence intervals are calculated so that if we repeated the study many times, 95% of the time the true unknown value would lie between the lower and upper confidence limits. A wider interval indicates more uncertainty in the estimate. Overlapping confidence intervals indicate that there may not be a true difference between two estimates.
For more information, see our methodology page on statistical uncertainty.
Free school meals (FSM)
Free school meals (FSM) are a statutory benefit available to school-aged children from families who meet the qualifying criteria (predominantly based around income). This is published by the Department for Education.
An odds ratio indicates the likelihood of staff having a positive test for coronavirus (COVID-19) given a particular characteristic or variable, compared with a baseline category. When a characteristic or variable has an odds ratio of one, this means there is neither an increase nor a decrease in the odds of having tested positive for COVID-19 compared with the baseline category. An odds ratio greater than one indicates an increased likelihood of having a positive test for COVID-19 compared with the baseline category. An odds ratio less than one indicates a decreased likelihood of having reported a positive test for COVID-19 compared with the baseline category.
The staff workforce covers a large range of roles which have been categorized into three staff types; teaching staff, teaching assistants and support staff. Teaching staff encompasses classroom teachers, leading practitioners, advisory teachers, head teachers, as well as deputy and assistant head teachers. Support staff covers a wide range of roles, including administrative, catering, caretaking, nursing, and technician positions.
The outcome measure includes positive polymerase chain reaction (PCR) test results recorded by the testing labs or lateral flow device (LFD) test results reported by individuals on the NHS Test and Trace system. Several positive tests can be recorded for each individual. Up until 20 December 2021, we consider positives more than 120 days after the first positive of that infection episode to be new infections in order to be consistent with our existing publications on COVID-19. From 20 December 2021 onwards, positives more than 90 days after the first positive of that infection episode are considered a new infection.
Variants of COVID-19
In the time periods analysed in this article there have been different dominant variants of SARS-CoV-2, the virus causing COVID-19, at each point in time. In the autumn 2020 term, the original strain of COVID-19 was dominant, with Alpha emerging towards the end of the term and becoming dominant on 21 December 2020. In the Autumn 2021 term, Delta was the dominant variant. Omicron infections were identified towards the end of this term but were not considered dominant until 20 December 2021. Omicron was the dominant variant in the spring 2022 term.Back to table of contents
Measuring the data
Data from the School Workforce Census (SWC), NHS Test and Trace (pillars 1 and 2), and the National Immunisation Management Dataset (NIMS) were linked to produce the analysis used in this article.
The SWC is a mandatory annual return to the Department for Education and collects individual level data for all types of staff in state-funded schools in England with a contract of 28 days or longer. The Department for Education releases SWC data.
Staff in the SWC are linked to their NHS number which allows onward linking to their coronavirus (COVID-19) test results and vaccination records.
The SWC does not contain the home postcode for school staff (which is a commonly used data item in data linkage). To reduce the risk of linking staff in the SWC to the incorrect NHS number, the postcode of the school was used in the process to restrict matches to those living within a reasonable commuting distance to the school.
The match rate for SWC staff to their NHS number was 86% for primary school staff and 75% for secondary school staff, which is lower than that seen when matching pupils with the English Schools Census (98%). In part, the lower match can be attributed to the lack of geography information available and strict guidelines intended to ensure accurate matches. Analysis of the unmatched population by key characteristics such as gender and ethnicity revealed no obvious systematic bias between the matched and unmatched population (see accompanying dataset).
School staff may have multiple roles either within the same school or work across different schools. In the figures presented in this bulletin, each individual is only counted once and the record relating to the highest full time equivalent (FTE) has been used.
NHS Test and Trace recorded all COVID-19 testing that took place in England. The outcome measure includes individuals receiving a positive polymerase chain reaction (PCR) or lateral flow device (LFD) test result reported in the NHS Test and Trace data.
From the spring 2020 to 2021 term onwards school staff were advised to take two LFD tests twice a week. Variation in the uptake and/or reporting of LFD testing could also affect the trends reported here. From 11 January 2022, the need for a confirmatory PCR test following a positive LFD test result was dropped placing greater reliance on the individual to record the result on the NHS Test and Trace system.
From 21 February 2022 onwards, the guidance to test twice a week was dropped. From 24 February 2022, close contacts were no longer required to test daily for seven days and from 31 March 2022, access to free COVID-19 testing ended for the majority of the population in England. These changes will further affect the identification of new infections in the second half of the spring 2022 term. The large increase in cases reported in the Coronavirus (COVID-19) Infection Survey from mid-March 2022 is not seen in NHS Test and Trace data. See Coronavirus (COVID-19) latest insights: Comparisons for more information.
This is analysis of newly collected data, and our understanding of it and its quality will improve over time. The estimates presented in this article are experimental statistics as the NHS Test and Trace data are subject to further quality assurance tests.
NIMS records England’s COVID-19 vaccinations programme.
Logistic regression model
To control for any differences in the characteristics of those who received a third dose compared with those who only received two, a logistic regression model was fitted.
Staff who received their third COVID-19 vaccine dose more than 44 days before the start of the spring term 2022, or during the spring term, were excluded from the model. This meant our vaccine statuses contained staff members who had received their third dose close to the start of the term and whose vaccine status did not change in the period of interest. Those with no or one vaccine dose were also excluded.
Those who had a positive COVID-19 test less than 90 days before the start of the spring term 2022 were also excluded from the analysis, leaving in the analysis only vaccinated (two and three doses) staff who were “at risk” of a new infection for the full duration of the spring term. Full details of all the variables included in the model can be found in Table 24 in the accompanying dataset.
One strength of the dataset is its size. The SWC contains data for all staff in state-funded schools in England. Over 900,000 staff were matched and retained in the linked dataset. This allows for potential analysis of school staff in under-represented groups.
The data contain a rich source of background characteristics. These allow us to analyse how proportions of staff reporting positive COVID-19 tests differ by demographic group and examine the extent to which these differences are driven by other factors.
Making use of already existing administrative data sources avoids the need of setting up bespoke surveys which can be costly and suffer from response bias.
Using NHS Test and Trace data to monitor trends in COVID-19 infection relies on infections being diagnosed, which is influenced by:
whether people have symptoms
awareness they may have been a contact of someone infected
a willingness to test
Changes to the availability of tests and isolation rules over time may also influence the willingness to test and the impact of these rules and any changes could vary between different socio-demographic groups. This means the NHS Test and Trace data cannot be used to provide an estimate of the true positivity rates within the population.
We are not able to confirm whether positive tests that we have classified as reinfections are actual new infections or a continuation of a previous infection as this would require genetic sequencing. Conversely, by only counting positive tests occurring 90 days after the first positive in the previous infection episode we may be missing genuine new infections that occurred in a shorter space of time.
The latest data available for analysis relate to the census carried out on 3 November 2020. Therefore, analysis for the autumn 2021 and spring 2022 terms relates to staff employed in the previous academic year, some of which will no longer be employed in schools. Those joining the school workforce after this date will also be excluded from the analysis.
The SWC does not collect geographic or demographic data in as much detail as the pupil equivalent (the English School Census), this has mainly affected analysis by deprivation. As we do not have any information on where school staff live, we are only able to look at deprivation in relation to the school where they teach.Back to table of contents
We will continue to examine the analytical potential of the linked data asset and expand on our existing analysis.Back to table of contents
This analysis was produced by the Office for National Statistics (ONS) with support from our School Infection Survey research partners at the London School of Hygiene and Tropical Medicine and UK Health Security Agency.Back to table of contents
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