Teachers not at greater risk of Covid infection than other working adults, study finds

Research shows ‘schools are not amplifiers of infection, as some have feared’

Teachers are not at a greater risk of infection than other working adults in the population, scientists have said, as the government prepares to reopen all primary and secondary schools in England.

The latest findings from the second round of the Schools Infection Survey, released via the Office for National Statistics, suggest school infection levels in late 2020 were similar to those found in the community.

Between 2 and 10 December, an estimated 14.61 per cent of primary school staff tested positive for Covid-19 antibodies, while this figure rose to 15.72 per cent for secondary staff.

The positive rates from the previous round of testing, conducted between 3 and 19 November, stood at 12.63 per cent and 12.27 per cent respectively for primary and secondary teachers.

Since the launch of the study, which is co-led by the London School of Hygiene & Tropical Medicine (LSHTM) and Public Health England (PHE), 14.99 per cent of teachers have tested positive for antibodies.

This is lower than the national average for all working adults, which was estimated at 18.22 per cent for early December.

A total of 121 schools (41 primary and 80 secondary) across England took part in the second round of testing, which involved 5,114 staff and 7,089 pupils.

Professor James Hargreaves, an epidemiologist at LSHTM and the study’s co-chief investigator, told a press briefing on Monday that the findings suggest there isn’t a notably higher risk of infection among teachers.

“We’re all very keen to make two additional points: one is that that does not mean there’s no risk, and there are risks of infection at any point if there is virus circulating in the community,” he said.

“The second thing is … schools are working hard to control transmission.

“While we’re not set up to make any direct comment on the effectiveness of any one of those measures, the combination of these factors does suggest that teachers are not at greater risk than other working age adults in the population.”

The findings are “consistent” with a range of other investigations that have been conducted in the UK and beyond, Prof Hargreaves added.

All data in the study is taken from a small sample of schools in 15 local authorities where transmission was high at the time of testing. This means no firm conclusions can be drawn from the findings.

The survey, which is set to restart once schools are reopened next week, does not control for any characteristic differences between staff and the working-age population, such as age and sex.

And the data reported in the research only includes individuals who were present in the school on the day of testing. Anyone who had known contact with a positive case or was symptomatic on the day would have been advised to not attend school.

“This could well bias the estimates of infection levels in school downwards,” said Kevin McConway, Emeritus Professor of applied statistics at The Open University, who was not involved in the study.

Scientists also commented that the research was unable to offer any insight on how and when transmission occurs in schools.

“The design of this study doesn’t allow any clear conclusions to be drawn about that,” Prof McConway added.

Almost all primary schools included in the survey (38) reported implementing 10 measures strongly recommended in Department for Education (DfE) guidance.

Some 91 per cent of secondary schools reported implementing at least 12 of 15 strongly recommended measures. The least commonly implemented measure was maintaining distance between pupils within bubbles.

Dr Shamez Ladhani, a consultant paediatrician at PHE and the study’s chief investigator, said the risk of infection to teachers was low and that “we’re in a much better place than we’ve ever been before” to reopen schools.

“If you look at other institutions, such as care homes, or hospitals or prisons, you expect to find much higher rates,” he said. 

“We know that these involve students and students may be at lower risk of infection and transmission, but it also involves a lot of staff. There is an opportunity for a lot of transmission to occur within these settings. 

“What we’re finding is that there aren’t any. One of the most likeliest reasons that we don’t see widespread infections in schools must be because of all the mitigation processes that are in place. 

“Difficult as they may be … they certainly play a huge role in keeping infection rates low.”

Under government plans to safely reopen educating settings from 8 March, families with children in school or college will be able to test themselves for coronavirus twice a week from home.

Free tests will be provided to pupils’ households, as well as those in their childcare or support bubbles, regardless of whether anyone has symptoms.

Modelling from government scientists has meanwhile shown that the reopening of schools in England on 8 March could push the country’s R rate above 1.0, raising concerns among education chiefs over the safety of teachers.

Addressing the LSHTM and PHE research, Russell Viner, professor of adolescent health at University College London, said: “In essence the study suggests that school levels of infection in late 2020 were similar to community levels for both adults and children. 

“This suggests that schools are not amplifiers of infection, as some have feared, but that school infections largely reflect community virus levels.”