A new Covid-19 test that could return results in just 20 minutes telling someone whether they have the virus is being trialled.

Up to 4,000 people will take part in a pilot in Hampshire, after the rapid test proved effective in clinical settings, the Department of Health said.

The swab test will be carried out in a number of A&E departments, GP testing hubs and care homes in the county in a trial lasting up to six weeks.

The loop-mediated isothermal amplification (LAMP) swab can be processed on-site rather than needing to be sent to a lab, and could mean healthcare workers can, depending on the result, return to a shift or isolate on the same day they take the test.

This is different to the PCR (polymerase chain reaction) tests which need to be processed at different temperatures meaning it takes longer to get results.

This could change the way that we control Covid-19 across the country, getting those with negative results back into society as quickly as possible

The new trial comes amid criticisms that people have been waiting days or weeks to get test results.

If the pilot is successful the test, developed by UK manufacturer Optigene, will be rolled out more widely, the department said.

Individuals with symptoms will be prioritised for testing in A&E departments and GP hubs but all staff and residents will be tested in care homes whether they are symptomatic or not.

Hampshire Hospital NHS Trust, which is leading the trial, will work closely with local authorities to identify priority care homes to visit and test, the department added.

Health Secretary Matt Hancock said: “This new test could provide accurate results almost on the spot. This will enable health and care workers to carry on with their shift or immediately isolate on the same day, and could eventually offer the same benefit to the whole country.

“This could change the way that we control Covid-19 across the country, getting those with negative results back into society as quickly as possible.

“I am hugely grateful for everyone in Hampshire for making this innovation possible.”

Trust chief executive Alex Whitfield said: “We are tremendously excited to be able to support the government’s efforts for ever more accessible, faster coronavirus testing.

“That we are able to do so is a testament to the hard work and ingenuity of our entire microbiology department, from clinical scientists and the laboratory team to volunteers from academia and industry as well as the staff on the wards.

“We are very much looking forward to the results of this trial and the benefits it will bring to the community we serve.”

This antigen test, showing whether you currently have the virus, is different to antibody tests, which show if you have already had the virus.