Two-thirds of people testing positive for coronavirus have no symptoms, according to Office for National Statistics (ONS) data.
The new figures suggest there is a potentially large number of asymptomatic cases – meaning the virus could be spread by people who don’t realise they are carrying it.
Only 33 per cent of those testing positive for Covid-19 reported any evidence of symptoms at the time of their swab test or at either the preceding or subsequent swab test, ONS analysis shows.
Download the new Independent Premium app Sharing the full story, not just the headlines Download now
This falls to 22 per cent when accounting for those who reported evidence of symptoms only at the time of their swab test.
The ONS analysis is based on a small sample of 115 individuals from private residential households in England who tested positive for Covid-19 and does not include hospitals, care homes and other institutional settings.
It found those working outside the home show higher rates of positive swab tests than those who work from home.
Infection rates are higher for those working in patient-facing healthcare or resident-facing social care roles than for people not working in these roles, the data suggests.
There is also some evidence to suggest infection rates are lower in one- and two-person households than in larger households.
Antibody test result data also indicates white people are less likely to have had Covid-19 in the past than non-white ethnic groups.
It comes as ONS data shows coronavirus-related deaths in England and Wales have officially reached 50,000.
Data published on Tuesday shows there were 50,000 cases where Covid-19 was mentioned on death certificates between 28 December and 26 June.
The number of deaths registered in both countries in the week ending 26 June was 8,979 – down 360 from the previous week, ONS said.
Boris Johnson has been condemned for appearing to suggest that care home bosses were to blame for the large number of deaths in those settings.
“We discovered too many care homes didn’t really follow the procedures in the way they could have,” the prime minister claimed on Monday as he addressed concerns raised by NHS chief executive Simon Stevens.
The National Care Association said the remarks were a “huge slap in the face” to those working in the sector, with the National Care Forum branding the comments “hugely insulting”.