The number of people with Covid-19 has remained stable for the third week in a row, according to the Office for National Statistics, with an estimated 133,000 people infected in England in the last two weeks.
The findings raise questions about whether community transmission rates are low enough to avoid a second surge in infections as lockdown measures start to be lifted.
The figure from the snapshot infection survey is marginally lower than the 137,000 and 148,000 current infections estimated for the two survey periods, but the ONS said the small change was not statistically significant. “Our interpretation is that it’s stable and flat,” said Peter Benton, director of population and public policy operations at the ONS.
The study also found that one in 15 of those tested carried antibodies for Covid-19, suggesting the vast majority of people in England have not yet been infected and are not immune.
Prof Sarah Walker, of Nuffield department of medicine at the University of Oxford, which is jointly running the study, said: “If people had seen figures of 40% or 60% people [with antibodies, then they] would’ve been excited about the potential for herd immunity. But with a level of 6.8% I don’t think that’s even something that’s worth talking about.”
Researchers also found that of those who have tested positive in the study so far, only 30% reported experiencing symptoms at any point during the course of the study, indicating that many people may be unaware that they have been infected.
However, the researchers noted that it waas not yet clear whether people who were asymptomatic were as likely to infect others. The survey is examinnng within-household transmission to try to answer this question.
People working outside of the home were found to be more likely to test positive (0.71% over the study to date) compared with those working at home (0.23%) and those working in patient-facing roles in healthcare settings also appeared to be four times more likely than those in other jobs to test positive.
“It certainly suggests that being out and being exposed is leading to a higher prevalence rate,” said Walker.
The analysis, which is based on tests on 18,913 people in 8,799 households, did not provide a direct estimate of the current R number – the level of transmission in the community. However, Benton said the data was being used by modelling teams working with the Sage advisory group on estimates of R that was being used to guide government decision-making. The analysis suggests the current rate of new infections is about 8,000 per day in the community, which is an incidence rate per week of 0.10 new cases per 100 people.
