Alternative approaches
An alternative approach for estimating the spread of the COVID-19 virus undertaken by Dimdore-Miles and Miles (5) used predictive mathematical modeling for the UK and other countries and applied this to daily new cases of the virus. As did our projection, they favoured high values for the number of people infected but asymptomatic, with a multiplier of approximately 200 on the diagnosed cases of COVID-19 in late April 2020, to derive a total population estimate of infection (5). The authors, acknowledged that the result is very sensitive to whether the transmission rate of the virus is different for symptomatic and asymptomatic cases, something about which there is significant uncertainty. The differences between the estimates given by different models, illustrate how difficult it is to estimate the spread of the COVID-19 virus until very large samples of the population can be tested, as is now happening in the UK.
Nevertheless the fact that the Office of National Statistics (ONS) weekly results (6) suggest that around 80% of people testing positive for COVID-19 have no symptoms suggests that COVID-19 infections in many cases have a minimal impact on health, as severe / life threatening as the infection may be in others.