SARS-CoV-2 infection in UK university students: lessons from September–December 2020 and modelling insights for future student return

Abstract

In this paper, we present work on SARS-CoV-2 transmission in UK higher education settings using multiple approaches to assess the extent of university outbreaks, how much those outbreaks may have led to spillover in the community, and the expected effects of control measures. Firstly, we found that the distribution of outbreaks in universities in late 2020 was consistent with the expected importation of infection from arriving students. Considering outbreaks at one university, larger halls of residence posed higher risks for transmission. The dynamics of transmission from university outbreaks to wider communities is complex, and while sometimes spillover does occur, occasionally even large outbreaks do not give any detectable signal of spillover to the local population. Secondly, we explored proposed control measures for reopening and keeping open universities. We found the proposal of staggering the return of students to university residence is of limited value in terms of reducing transmission. We show that student adherence to testing and self-isolation is likely to be much more important for reducing transmission during term time. Finally, we explored strategies for testing students in the context of a more transmissible variant and found that frequent testing would be necessary to prevent a major outbreak.

Impacts of vaccination and asymptomatic testing on SARS-CoV-2 transmission dynamics in a university setting

“…Our work suggests that asymptomatic testing is a useful supporting measure and can help to further reduce case numbers, having the most impact at low to medium levels of vaccination uptake. This corroborates previous findings reporting that asymptomatic testing is more impactful at higher reproduction numbers 8-10 . Reliably estimating uptake of asymptomatic testing is challenging.…”

“…Previous work using age-stratified and geographical spread analyses found signals for spillover of COVID-19 from universities to the community in some local tier local authorities in England, but not in others. However, the analysis was not able to identify specific risk factors for transmission between universities and the community 8 . Therefore, our work cannot give any exact predictions or quantitative estimates for the impact of importation of COVID-19 from the community into the student population.…”

“…Testing of asymptomatic individuals leads to increased case detection and may be particularly important in the university student population where, due to the younger age structure, cases are more likely to be asymptomatic 6,7 . Previous modelling of asymptomatic testing in a university found that adherence to testing and isolation was important for reducing transmission 8 , particularly at high values of the reproduction number 8-10 .…”

Rapid evidence review to inform safe return to campus in the context of coronavirus disease 2019 (COVID-19)

“…Ideally, a blended learning option should be offered in which those who wish to join the class remotely are supported to do so (especially if they or a household member are clinically vulnerable). Staggering the start dates of students does not appear to reduce on-campus transmission 35 .…”

“…Test, trace and isolate while COVID-19 incidence is high In the context of high incidence of COVID-19 and an unvaccinated or partially-vaccinated student population, frequent testing of asymptomatic staff and students along with contact tracing and support to isolate has been shown to reduce on-campus transmission substantially 35 . While lateral flow device (LFD) tests can detect asymptomatic cases and break chains of transmission, this measure depends on the efficacy of efforts to track and trace contacts and maintain and support the isolation of infected individuals.…”