An investigation has been launched after lateral flow tests were given to millions of schoolchildren with the wrong instructions.
The rapid tests came with out-of-date guidance that says they can be used by people who have symptoms of Covid-19, reports The Telegraph.
Testing kits handed out this month are accompanied by a government leaflet – 'Version 1.1.4, 24 November 2020' – which states: “You can use this self-test kit if you have symptoms or if you are asymptomatic."
There is also a notice in the box, from the Chinese manufacturer Xiamen, that says the tests were for people “suspected of Covid-19 by their healthcare provider”.
The Medicines and Healthcare products Regulatory Agency (MHRA) is now investigating.
Government guidance states the lateral flow tests, that provide results in 30 minutes, are for people who are asymptomatic and anyone showing symptoms of the virus should take a laboratory PCR test and self isolate.
That's because the results of the PCR swab tests - the most accurate tests available - are reported automatically and this triggers the contact tracing process.
There are concerns that people who use lateral flow tests may not report positive results, self isolate or alert contact tracers.
Secondary school pupils and teachers are required to take a lateral flow test twice a week.
Earlier this month, the government began offering the free weekly tests to everyone in England, in a bid to stop people with no symptoms transmitting the virus without realising.
Around one in three people who contract Covid-19 don't show any symptoms.
Professor Allyson Pollock, a public health expert at Newcastle University, told The Telegraph : "The whole mass testing programme is confusing, chaotic and the antithesis of good public health practice.
“If you do mass testing you need to do proper evaluation beforehand, which would identify problems like this.
“Lateral flow testing should have gone through the UK National Screening Committee for proper evaluation.”
The government spent £1.3 billion on up to 384 million lateral flow testing kits and most of them were made by US firm Innova Group, according to the British Medical Journal.
Public Health England research found the Innova tests were successfully detected cases of Covid-19 in 79.2 per cent of cases, when used by trained laboratory scientists.
But they were only 57.5 per cent effective when used by track and trace centre staff employed by Boots.
In January, University of Oxford researchers found the lateral flow tests are "sufficient" at detecting the "most infectious" people, who have high viral loads.
A Downing Street spokesman said lateral flow tests had been “rigorously evaluated".
He added: "We believe they are both accurate and incredibly useful in terms of being able to spot asymptomatic cases of the virus”.
