1 Million People Harbouring COVID-19 in England: Swab Survey

A worker collects a swab test from a member of the public at a COVID Test site in South London on Sept. 15, 2020 ( Dan Kitwood/Getty Images)

The number of COVID-19 infections is doubling every nine days in England, according to a large-scale population swab survey that estimates around one million people are harbouring the virus.

According to the study authors, “the second wave of the epidemic in England has now reached a critical stage.”

However, scientists say the results do not reveal the impact of recently introduced measures due to a time lag.

Infections have been rising across the country, according to the government-commissioned study published today, and is highest in Yorkshire and The Humber, where levels are at 1 in 40 people.

The lowest prevalence is in the eastern and southern parts of the country, including London.

The REACT-1 study, carried out by Imperial College, uses nose and throat swabs collected from 160,000 people over a two-week period, and then does a PCR test on them in a lab.

The researchers, however, chose to publish the results from only half of the number of planned swabs, in today’s “interim report,” meaning the data was made public earlier.

The results showed that 1.28 of participants had the CCP virus, with an “R number” of 1.56 nationwide, indicating a national doubling time of 9 days.

“Based on our prevalence estimate at the national level of 1.28 percent, we estimate that 960,000 ... individuals are harbouring SARS-CoV-2 virus in England on any one day,” said the report.

NHS workers in PPE take a patient with an unknown condition from an ambulance at St Thomas' Hospital on April 10, 2020, in London, England. (Justin Setterfield/Getty Images)

Assuming that the virus can be detected 10 days after infection, that corresponds to 96,000 people becoming infected each day.

“The size and design of our study mean we’re able to offer detailed insight in the current situation of England’s epidemic,” said Dr. Steven Riley, study author and professor of infectious disease dynamics at Imperial College, which carried out the study.

“It’s too early to tell whether recent stricter measures are having an effect, which is why continued monitoring is vital to understand what works and adapt responses accordingly,” said Riley.

Dr. Paul Hunter, professor of medicine, University of East Anglia, said the result indicate that infection rates now are likely very similar to and maybe even higher than at the peak in April.

Hunter said that the results confirm those of other major studies, which together point towards a rapidly increasing epidemic. “But because of the lag between becoming infected and developing a positive test such data does not necessarily tell us what may be happening now with recent changes in restrictions,” he added.

The study showed an increase in positive tests across all ranges. The highest level of infections in different age brackets is still in the 18–24 age range, but the rate is growing fastest in the 55–64 age range.

According to the latest government data, 310 deaths of people with COVID-19 were recorded in the last day.