NHS test and trace adviser defends mass use of rapid Covid tests

The mass use of rapid coronavirus tests has been defended by a top NHS test and trace official, after experts warned they were not fit for use.

Government figures from the mass testing programme in Liverpool showed that the tests missed half of all positive cases detected by the standard coronavirus tests, and missed 30% of those with a high viral load – likely to be the most infectious.

The tests have been used to allow visitors into care homes, and to enable university students to return home for Christmas, but experts warned they were not reliable in these situations, and gave people “false reassurance” that they did not have coronavirus.

Dr Susan Hopkins, the chief medical adviser to NHS test and trace, defended the use of the tests, saying they had picked up many cases of infection which would otherwise have been missed.

“What we are doing here is case detection. We are not saying people do not have the disease if their test is negative,” she told the BBC Radio 4 Today programme on Saturday. “We are trying to say [to people who test positive]: ‘You do have the disease and now we want you to go and isolate for 10 days.’ That is a whole different gamechanger.”

Hopkins also said the tests did not mean that social distancing measures could be ditched.

“We have been very clear that this test finds people we couldn’t otherwise find. We are also very clear that until we get a much lower prevalence of disease in this country that we shouldn’t be changing our behaviours,” she said.

Cases in UK

Prof Calum Semple, of Liverpool University and a member of the government’s Scientific Advisory group for Emergencies (Sage), said the rapid tests had improved the reach of mass testing in Liverpool, meaning that 85% of the city’s population were just a 15-minute walk from a testing centre.

“This means we have broken over a thousand transmission chains in those hotspot areas,” he told the Today programme. “We are increasing the safety of an activity that is going to happen anyway. In this case we are breaking transmission chains and that is really important.”

But Prof Jon Deeks of Birmingham University said the tests were never intended to be used en masse, and called for the practice to end.

“They are a low-tech test, they can’t detect low levels of the virus. The World Health Organization has said: ‘Don’t use it for this purpose’, the manufacturer said: ‘Don’t use it for this purpose,’” he told Today.

“We can’t see why the government is progressing with using this test when it is missing so many people. They have been sold to people with the idea that if you are negative you will be able to go and visit people, you will be able to be clear that you haven’t got Covid, and that is really dangerous.”