View article

We investigate the impact of vaccination and asymptomatic testing uptake on SARS-CoV-2 transmission in a university student population using a stochastic compartmental model. We find that the magnitude and timing of outbreaks is highly variable depending on the transmissibility of the most dominant strain of SARS CoV-2 and under different vaccine uptake levels and efficacies. When delta is the dominant strain, low level interventions (no asymptomatic testing, 30% vaccinated with a vaccine that is 80% effective at reducing infection) lead to 53-71% of students become infected during the first term. Asymptomatic testing is most useful when vaccine uptake is low: when 30% of students are vaccinated, 90% uptake of asymptomatic testing leads to almost half the case numbers. With high interventions (90% using asymptomatic testing, 90% vaccinated) cumulative incidence is 7-9%, with around 80% of these cases estimated to be asymptomatic. However, under emergence of a new variant that is at least twice as transmissible as delta and with the vaccine efficacy against infection reduced to 55%, large outbreaks are likely in universities, even with very high (90%) uptake of vaccination and 100% uptake of asymptomatic testing. If vaccine efficacy against infection against this new variant is higher (70%), then outbreaks can be mitigated if there is least 50% uptake of asymptomatic testing additional to 90% uptake of vaccination. Our findings suggest that effective vaccination is critical for controlling SARS-CoV-2 transmission in university settings with asymptomatic testing ranging from additionally useful to critical, depending on effectiveness and …