Covid-19 infection rate witnessed declining trend in May: study

The rate of Covid-19 infection recorded a declining trend in May, the last month of lockdown, halving every eight to nine days, a latest study has showed.

There were on average 13 positive cases for every 10,000 people, with an overall reproduction number of 0.57 – lower than previously reported, the research by Imperial College London revealed.

The findings indicate that the virus was circulating with relatively low prevalence and was declining in May, ahead of the decision to ease lockdown restrictions.

Health Secretary Matt Hancock said the findings show the impact of lockdown, besides confirming that the government has "taken the right actions at the right time."

"As a country we have made great strides towards beating this virus but we mustn’t take our foot off the pedal, and such studies will be vital as we continue to fight this virus," he added.

Over 120,000 volunteers tested across England between 1 May and 1 June, as part of the country’s largest study into coronavirus.

The report also shows anyone who had recent contact with a known Covid-19 case was 24 times more likely to test positive than those with no such contacts.

Other key findings include:

• Young adults, aged 18 to 24, were more likely to test positive than other age groups, reinforcing the need for this age group to adhere to social distancing measures to protect vulnerable friends and family.
• Those of Asian ethnicity were more likely to test positive than those of white ethnicity. It is possible that higher infection rates have contributed towards the higher death rates observed in this ethnic group.
• Care home staff and healthcare workers were more likely to be infected with Covid-19 during lockdown than the general population, at a time when the public was following government advice to stay at home, therefore limiting their exposure to the virus. Those who had patient facing roles were more likely to be in contact with known cases as part of their work.

Professor Paul Elliott, director of the programme at Imperial College London, said: "Community testing is a vital step in ongoing efforts to mitigate the pandemic, but to be successful this must be based on robust scientific evidence and sound statistics.

"Through this surveillance programme with DHSC and Ipsos MORI we’re gathering the critical knowledge base necessary to underpin community testing and facilitate a greater understanding of the prevalence of Covid-19 in every corner of England."