The government needs to make sure its coronavirus testing strategy is fit for purpose instead of focusing on hitting targets, says the Royal College of GPs.
In a letter to Health Secretary Matt Hancock, chairman Prof Martin Marshall said long wait times were “undermining confidence” in the results.
Health professionals were also concerned about the accuracy of some test results, he said.
The government said “95% of tests” were processed “in less than 48 hours”.
Ensuring there are enough tests to meet demand is part of the government’s five tests it says must be met before easing lockdown restrictions.
However, the absence of a clear strategy had left patients vulnerable, according to Prof Marshall.
He said the RCGP did not currently believe the testing strategy was capable of working to prevent a second wave of infections and “secure the overall health of the population”.
However, he did commend the “clear strides to improve testing capacity” in recent weeks.
The RCGP said it wants the testing strategy to:
Continue to ensure the right people are tested at the right time to protect key workers and vulnerable patients
Help us understand the virus and its spread better through test, track and trace
Deliver timely results that patients and healthcare professionals can have confidence in
Include a commitment to improve the accuracy of the tests
Make sure GPs and care homes have access to tests
There was a major effort to increase the number of daily tests provided, with a target set of hitting 100,000 tests a day by the end of April.
The government said it had reached that goal, providing 122,347 tests on 30 April – although it has struggled to maintain testing numbers at that level over the past fortnight.
The number also included home testing kits which had been sent out but may not end up being returned.
Target a ‘distraction’
Concerns have been raised that the focus on hitting the target had distracted from the actual purpose of testing.
At the end of April, NHS Providers deputy chief executive Saffron Cordery told the BBC there were questions to be asked about whether the “maximum benefit” had been gained from efforts to meet the 100,000 target, when a plan to test frontline staff regularly “hadn’t been thought through”.
Testing key workers is meant to help those who can get back to work faster.
But some health professionals have reported waiting more than a week for results. Dr Lucy-Jane Davis, chair of the British Medical Association (BMA) in south-west England, said some people had waited more than 10 days.
A test to see if someone has the virus is only a snapshot in time – it indicates whether the person has enough of the virus in their nose or throat to be detected at that moment.
If they are re-tested a few days later, it may have cleared up, multiplied enough to become detectable, or show whether they have newly contracted the virus.
So people receiving their results several days after being tested may find that information is no longer useful or accurate.
The Department of Health and Social Care (DHSC) says 95% of tests across all settings are received back within 48 hours – but that still gives a figure of potentially 5,000 people a day waiting longer than that.
On top of this there is also a “void rate” of just over 5% – where the samples are not viable and so the swabs cannot produce a result.
Staff on the frontline in hospitals and care homes may need to be tested once or even twice weekly, regardless of whether they have symptoms or not, according to Rupert Beale who is leading the Crick Institute’s efforts to test NHS staff.
The DHSC says the key window for testing is the first three days after developing symptoms.
The ability to have rapid results will also play a key role in the government’s “track, trace, test” efforts, according to Prof James Naismith at the University of Oxford.
Faster turnaround is needed if testing is to be used to help control the spread of infection, he said.