Key workers doing swab samples at home may ‘do more harm than good’
Experts warn lack of training could lead to false results and infectious people returning to work
HOME testing kits for Covid-19 being dispatched by the Government could be putting more lives at risk because of the danger of misuse, a senior adviser to the World Health Organisation (WHO) warned last night.
About 5,000 tests a day are being sent to home addresses by courier, allowing key workers with symptoms of the disease to take their own swab.
The swab sample, taken from the nose, is then returned to a centralised laboratory for testing and the results made available within 72 hours.
But experts warned last night that leaving swab testing to untrained key workers – including supermarket employees and care home staff – could result in tests being returned negative because the swab was not obtained correctly. That raises the prospect of infectious victims of Covid-19 going back to work because the test has given a “false” negative.
Professor Paul Hunter, an adviser to the WHO and a chair of medicine at the University of East Anglia, said: “Taking a nose swab or a throat swab is not an easy test to do. You do need to be trained in how to use it. People are easily muddled.
“That is a big worry. These home tests could be doing more harm than good because people with coronavirus could be going back to work when they have the virus but have tested negative because they have taken the swab wrongly.”
The mass testing for virus was thrown open last week to all key workers and those living in the same households – amounting to about 10 million people – at a time when Matt Hancock, the Health Secretary, was struggling to meet a self-imposed target of 100,000 Covid-19 tests carried out daily.
Figures for Saturday showed just 29,058 tests carried out, well short of Mr Hancock’s much trumpeted target of 100,000 by the end of April, in just four days’ time. Current testing capacity is a little over 50,000.
The Government had struggled to fill slots at drive-through regional testing centres which were restricted to NHS staff but have now opened them up to all key workers – supermarket staff and care workers as well as police, firefighters and journalists – with an online DIY booking system for those with symptoms. The home tests have been booked out within minutes of becoming available online, while the drive-through tests have been taken within hours.
Downing Street said last week 5,000 home tests were being made available, although some sources have suggested the numbers are being restricted and will be ramped up this week.
“There is a slight concern that the [home] swab test might not be of high quality,” said Prof Will Irving, chair of virology at the University of Nottingham, “but I would not guarantee that a professional taking the swab would necessarily produce a better swab.”
Home testing can only be scaled up if the swabs can be returned by post rather than by courier, but that has its own logistical problems. Swabs must be analysed within 48 hours, which could be thwarted by postal delays, and scientists are investigating ways of extending the shelf life of swab tests.
Meanwhile, thousands of care home residents and staff are yet to access testing, despite a spate of deaths.
Researchers found that out of 210 care providers, 159 said that none of their staff had been tested. The homes spoken to by BBC England look after nearly 13,000 residents and employ almost 18,000 staff.
The research also found that of 205 homes spoken to about tests for their residents, 127 said none had been tested. At homes that had seen tests conducted, 334 of 7,391 residents had been screened.