Impact of baseline cases of cough and fever on UK COVID-19 diagnostic testing rates: estimates from the Bug Watch community cohort study
Eyre M., Burns R., Kirkby V., Smith C., Denaxas S., Nguyen V., Hayward A., Shallcross L., Fragaszy E., Aldridge R.
Background Diagnostic testing forms a major part of the UK’s response to the current COVID-19 pandemic with tests offered to people with a continuous cough, high temperature or anosmia. Testing capacity must be sufficient during the winter respiratory season when levels of cough and fever are high due to non-COVID-19 causes. This study aims to make predictions about the contribution of baseline cough or fever to future testing demand in the UK. Methods In this analysis of the Bug Watch prospective community cohort study, we estimated the incidence of cough or fever in England in 2018–2019. We then estimated the COVID-19 diagnostic testing rates required in the UK for baseline cough or fever cases for the period July 2020-June 2021. This was explored for different rates of the population requesting tests and four second wave scenarios and then compared to current national capacity. Results The baseline incidence of cough or fever in the UK is expected to rise rapidly from 154,554 (95%CI 103,083 – 231,725) cases per day in August 2020 to 250,708 (95%CI 181,095 – 347,080) in September, peaking at 444,660 (95%CI 353,084 – 559,988) in December. If 80% of baseline cough or fever cases request tests, average daily UK testing demand would exceed current capacity for five consecutive months (October 2020 to February 2021), with a peak demand of 147,240 (95%CI 73,978 – 239,502) tests per day above capacity in December 2020. Conclusions Our results show that current national COVID-19 testing capacity is likely to be exceeded by demand due to baseline cough and fever alone. This study highlights that the UK’s response to the COVID-19 pandemic must ensure that a high proportion of people with symptoms request tests, and that testing capacity is immediately scaled up to meet this high predicted demand.