The staggered return of students to English universities is of “limited value” in terms of reducing Covid-19 transmission, according to research conducted for the Scientific Advisory Group for Emergencies.
A report was put together by the higher education working group at the Isaac Newton Institute and presented to Sage to assess the extent of university outbreaks, how those outbreaks may have spilled over into the community, and the expected effects of potential control measures.
The government has previously indicated that it would prefer to stagger the return of students to English campuses. Setting out the road map out of lockdown on 22 February, Boris Johnson said all students at English universities who require practical teaching would be allowed to return to campus from 8 March.
Until now, only students on certain courses – mostly health-related subjects, education and social work – have been allowed to return. The government said it would set out its plans for the rest of students by the end of the Easter holidays.
According to the research, staggering campus returns would “increase the prospect of repeated isolation of households” as the incoming cohorts would mix with already returned students. “At best, staggering may delay outbreaks to later in the term,” according to the paper.
The researchers used data from Public Health England, the Higher Education Statistics Agency, the Office for National Statistics and individual universities to model scenarios.
The authors note that there may be operational reasons why staggering returns is helpful, such as if a university was concerned about its testing capacity, but when it comes to overall infection their models suggest that the numbers would remain the same.
“We observed that staggering can reduce and delay the size of the infection peak in the short term. However, over the course of the 11-week term the reductions in the overall attack rate were minor, particularly for infections with high transmissibility,” they write.
The researchers also examined data from the autumn term to assess transmission from higher education outbreaks into the wider community. They compared PHE data with identified outbreaks in universities to see if there was an increase in the growth rate of community cases or more community cases than expected in the 10 days following the outbreak. They also employed age-stratified data, with those aged 18 to 24 used as a proxy for student cases, with cases among all other age groups being classified as “community cases”.
According to the report, “the dynamics of transmission from university outbreaks to wider communities are complex”. While “spillover” was sometimes found to have occurred, occasionally even large campus outbreaks created no spillover into the local population. For example, one of the large campus outbreaks – in excess of 1,750 cases – took place with relatively low levels of excess community cases.
“We do not see a consistent pattern across England, likely due to wide variations in both the course of the coronavirus pandemic and the nature of university-community interaction in different local authorities,” the authors write.
The researchers also found that students in halls of residence were much more likely to catch Covid-19, even if the halls were split into “households” that were asked to follow the national rules on mixing. They also found that students in halls where they all share a bathroom with at least one other were approximately 50 per cent more likely to become infected than students in halls with en suite bathrooms.
According to the researchers, adherence to isolation and test and trace guidance is the crucial element in breaking chains of transmission and effectively reducing the likelihood of large-scale outbreaks in universities.
They added that extremely frequent testing – all students every three days – would be necessary to prevent a major outbreak.
Another paper, published at the same time by Sage, also reported that it was hard to see patterns in university-to-community transmission because they are influenced by “a range of factors”, such as the relationship between community and students.
It said “anecdotal evidence from 10 universities” suggested that when face-to-face learning was happening “minimal cases of transmission were attributed to face-to-face learning environments”.
Instances where transmission did occur were associated with guidance not being followed, for example, the removal of a face mask, according to the paper.
