The UK’s lockdown measures appear to have made coronavirus less contagious than flu, research suggests.
When the virus hit Britain, scientists estimated that each positive case would infect 2.6 other people. But the new study, by the London School of Hygiene and Tropical Medicine, suggests the social distancing measures introduced by the Government mean that number could now be just 0.62.
Experts say maintaining this figure below one means the epidemic will decline. By comparison, seasonal flu is estimated to have a reproduction number around twice that, at 1.2.
The contagiousness of diseases is measured using estimates of its reproduction number – the average number of people who will catch a disease from a single infected person.
In an online survey, the London School of Hygiene and Tropical Medicine research team asked 1,300 individuals to list their contacts for the previous day. This was compared with a similar study from 2005-2006, which looked at the normal levels of contacts Britons have.
Using the change in contact patterns, the team calculated a change in reproduction number between standard behaviour and movements post-lockdown.
Researchers found that the mean number of contacts per person measured was 73 percent lower now than before the lockdown. This suggests the reproduction figure now would be between 0.37 and 0.89, with the most likely value being 0.62.
Professor John Edmunds, of the London School of Hygiene and Tropical Medicine, who led the research, said: “If we see similar changes across the UK population, we would expect to see the epidemic to start to decline.
“However, our estimates are not to be read as ‘job done’. Rather, they should be used as motivation for us all to keep following the UK Government instructions.
“It’s imperative we don’t take our foot off the pedal. We must continue to stop transmission of the virus to reduce the burden on the NHS now and over the coming months.”
Researchers said there were some limitations to the study, including the fact that contact with others the previous day was self-reported, meaning some instances might have gone unrecorded.
It also assumed that contact patterns from 2005-06 are similar to those in 2020. However, a recent study carried out by the BBC suggests this is the case in most age groups.