Antibody tests to identify those who have had Covid-19 will not be available until May at the earliest, raising further questions about how the government will reach its target of 100,000 tests a day by the end of the month.
On Wednesday Prof John Newton, of Public Health England, conceded none of the tests trialled so far were accurate enough.
“We do not expect to be doing antibody tests by the end of April,” Newton told MPs on the science and technology select committee. “We’re not relying on antibody tests to make up that target.
“We were optimistic that a number of companies have been offering us these quick antibody tests and we were hoping they would be fit for purpose. They all work to some extent, but are not good enough to rely on. The judgment was made that it is better to develop a better antibody test before rolling it out.”
Without an antibody test, experts believe it will be hard for the government to meet its 100,000-a-day target for testing patients, NHS staff and key workers such as carers, even with a massive effort by labs and the biomedical industry.
“It will be a stretch,” said Sir Paul Nurse, the Nobel laureate running the Francis Crick Institute in London, which has been converted into a testing lab.
The UK currently does about 14,000 swab tests a day to confirm whether patients currently have Covid-19, diagnostic tests that take time and need to be processed in laboratories.
When optimism about the potential usefulness of finger-prick rapid antibody tests was still high, Matt Hancock, the health secretary, announced the government had bought 3.5m of them, and later said he had ordered 17.5m more.
The hunt for a coronavirus vaccine
The UK will now be trying to get a refund, said Kathy Hall, director of the Covid-19 testing strategy at the Department of Health.
“We’re now working with companies to cancel the orders and get the money back where possible,” she told the committee. No country has a valid antibody test in use, she said.
Newton said he was encouraged that the UK pharmaceutical company Astra Zeneca was working on a test and was confident it could have one available in May. “The people who are doing it are talking about this kind of timescale,” he said.
Hancock held a conference call with industry leaders on Wednesday to urge them to help develop antibody tests, in the same way he had asked for industry’s support in making ventilators.
Antibody tests can identify who has recovered from the virus and gained some immunity, so could safely return to work. They are particularly important for doctors, nurses and carers, and in the later stage of the epidemic will allow other key workers, such as teachers, to resume their jobs.
Edward Argar, a health minister,defended the UK’s position after the chief medical officer for England, Chris Whitty, said there were lessons to learn from Germany, which tests many more people.
“I would absolutely expect him to say we need to look at what other countries have done that has had a really positive impact,” Argar told Sky News. “But I would come back to his caveats in which he did also say there were a whole range of factors for why Germany’s death rate does at the moment appear to be lower.”
A shortage of blood samples from people who have recovered from Covid-19 is also holding up development of an antibody test in the UK, it has emerged. Firms working on the tests need samples of convalescent blood to develop the tests and check they are accurate.
“Doris-Ann Williams, chief executive of the British In Vitro Diagnostics Association, said: “Access to patient samples has been a longstanding issue for the industry and that is highlighted now when companies desperately need them.
“We need to find a rapid process to allow access otherwise we can never move forward with development and validation.”
The shortage is affecting research across the board, from government to academia and biotech companies. One reason is that recovered patients with long-term antibodies against the virus are only now emerging, as the epidemic is still in its infancy in the UK.
Prof John Bell, an immunologist and regius chair of medicine at Oxford, said: “People can have two weeks of disease and then three weeks to mount this antibody response, but if you look back five weeks or so there was hardly anyone in Britain with the disease.”
