A senior NHS adviser has defended the massive use of rapid go-through coronavirus testing amid concerns that a high level of “false negatives” is giving people a misguided sense of reassurance.
Government figures released earlier this week from Liverpool – where the massive rollout of the lateral flow tests was first trialled – showed they missed half of all cases and a third of those with high viral load probably the most were contagious.
It sparked calls from some scientists to suspend its use amid fear that some people who tested negative would mingle with others who may be more vulnerable because they mistakenly believed they did not have the disease.
Dr. Susan Hopkins, NHS Test and Trace’s chief medical advisor, said the tests had enabled them to detect many cases of infection in people without coronavirus symptoms that would otherwise have been overlooked.
“What we’re doing here is case detection. We are not saying that people do not have the disease if their test is negative, ”she told the BBC Radio 4 Today program.
“We try to say (to people who test positive), ‘You have the disease and now we want you to isolate for ten days.’ That’s a completely different game changer. “
While other local authorities wanted to roll out the lateral flow tests, Dr. Hopkins that using it did not eliminate the need for social distance.
“We’ve been very clear that this test finds people we wouldn’t be able to find otherwise. We are also very clear that we should not change our behavior until we get a much lower prevalence of disease in this country. “
She was supported by Professor Calum Semple of the University of Liverpool and a member of the Government’s Emergency Scientific Advisory Group (Sage), who said 85% of the population is just a 15-minute walk from a testing center due to their commitment to town. .
“This means we have broken more than a thousand transmission chains in those hotspot areas,” he told Today.
“We increase the safety of an activity that will happen anyway. In this case we are breaking transmission chains and that is very important. ”
However, Professor Jon Deeks of the University of Birmingham said the tests were used in ways they were never intended for, with potentially dangerous consequences.
“They are a low-tech test, they cannot detect low levels of the virus. The World Health Organization has said ‘Do not use it for this purpose,’ the manufacturer said ‘Do not use it for this purpose,’ ”he told Today.
“We cannot see why the government is making progress in using this test when so many people are missing.
“They’ve been sold to people with the idea that if you’re negative, you can go and see people, you’ll be able to be clear that you don’t have Covid and it’s really dangerous.”