This article is more than 5 months old

This article is more than 5 months old

Unapproved antibody tests could increase people’s risk of becoming infected with coronavirus, the UK’s national testing coordinator has warned.

Countries around the globe are scrambling to develop reliable antibody tests that can detect if people have had the virus and may be immune, in the hope that this might allow for a loosening of lockdown restrictions – so far without success.

Reports have emerged that organisations and individuals are trying to acquire tests, with many of these testing kits likely to yield false results.

John Newton, the national coordinator of the UK coronavirus testing programme, believes efforts to develop accurate tests look promising, but said that “misleading” results of unapproved tests could increase the risk of becoming ill or spreading the virus.

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“The government, supported by world-leading experts and regulators, is continuing to work hard to rapidly deliver a reliable and accurate back-to-work antibody testing kit, to counter the spread of the virus and enable people to return to work safely,” Newton said.

“We are breaking new ground with this work every day and I am confident this major research effort will make a breakthrough.

“In the meantime, I advise organisations, both in the public and private sector, against the use of antibody tests that have not been verified in a laboratory setting – and none have.

The government has suffered several setbacks in its attempts to procure or develop reliable tests, which are widely believed to be the only chance of a gradual lifting of the national lockdown as long as there is no effective and available vaccine against Covid-19.

The health secretary, Matt Hancock, announced in March that 3.5m antibody tests had been bought, but researchers found that none of the tests meet the Medicines and Healthcare products Regulatory Agency (MHRA) standards, forcing the government to row back on claims the tests would be ready for a public rollout this month.

Newton said once reliable tests had been found, they would be used across the country “as a back-to-work test”.

Senior epidemiologists from the World Health Organization have said there is no proof people who have recovered from coronavirus have immunity and cannot be infected again.

“There are a lot of countries that are suggesting using rapid diagnostic serological tests to be able to capture what they think will be a measure of immunity,” WHO epidemiologist Maria Van Kerkhove, told a press conference in Geneva.

“Right now, we have no evidence that the use of a serological test can show that an individual has immunity or is protected from reinfection.

“These antibody tests will be able to measure that level of seroprevalence – that level of antibodies – but that does not mean that somebody with antibodies is immune.”

Van Kerkhove described the mass development of tests as “a good thing”, but urged caution.

“We need to ensure that they are validated so that we know they are actually measuring what they say they attempt to measure.”

Her colleague Michael Ryan said the antibody tests were a necessary element in any coherent public health strategy, but added: “There are serious ethical issues around the use of such an approach and we need to address it very carefully, we also need to look at the length of protection that antibodies might give.

“You might have someone who believes they are seropositive (have been infected) and protected in a situation where they may be exposed and in fact they are susceptible to the disease.”