LONDON — On May 1, a visibly relieved Matt Hancock announced that the British government had exceeded its target of 100,000 coronavirus tests a day. As health secretary, Mr. Hancock had set the goal after enduring intense criticism for the country’s lagging coronavirus testing program.
He called the milestone “an incredible achievement.”
But leaked documents and interviews with doctors, lab directors and other experts show that the push to hit the April 30 deadline — and arguably salvage Mr. Hancock’s career — placed a huge strain on public laboratories and exposed other problems that are now slowing efforts to further expand coronavirus testing.
Days before the deadline, some hospitals in England were given 48 hours to rapidly expand testing to thousands of health care workers and patients, even though they were not exhibiting any symptoms of the virus, the documents show.
At the same time, public labs across the country raced through limited supplies of the chemical reagents needed to carry out a flood of tests after the government promised to replenish their supplies. Two weeks later, some labs still haven’t received the stocks they need, forcing some to reduce the number of new tests they can process, several lab managers said.
“It was clear that the reason was for meeting the 100,000 target,” said Dr. Tom Gardiner, a junior doctor at St Mary’s Hospital in London, which received a call to urgently ramp up testing. “It was two days before the deadline, only lasted two days, and we haven’t heard it before or since,” he said.
Britain has recorded the most coronavirus deaths of any country in Europe, and Prime Minister Boris Johnson and his Conservative government have come under mounting criticism for an often-inconsistent response to the pandemic, especially on testing.
Mr. Hancock set the 100,000-test target at the beginning of last month, in response to growing pressure. Now Mr. Johnson has promised to increase the daily capacity for testing to 200,000 — except the system still hasn’t recovered from the frantic push to reach the initial goal.
In the two weeks since April 30, the government’s number of daily tests initially slipped well below 100,000, where it has remained for every day but three. A major problem is that Britain has far fewer domestic producers of reagents than the United States, Germany and China, and huge global demand has made supplies scarce.
“Since the 100,000 test target was passed, there appears to be a decline in the labs’ chemical reagents in terms of what they’re getting from the government,” said Allan Wilson, head of the Institute of Biomedical Sciences, which represents public lab workers. “It’s all hand-to-mouth, there’s no secure supply chain.”
Mr. Wilson said the government needed to develop a coherent testing strategy, rather than set arbitrary targets that could be counterproductive when the country’s supply chain lacked necessary amounts not just of reagents but even of the cotton swabs needed for testing.
“When we’re chronically short of tests and supplies, the government should be prioritizing those most in need instead of focusing on hitting a target,” said Bill Esterson, a Labour Party lawmaker who has been working closely with the country’s chemical industry.
A spokesman from the Department of Health and Social Care insisted that all labs had adequate supplies of reagents and said it was working “tirelessly” to scale up capacity.
“The scale and speed at which we have increased our testing capacity and rolled out mass testing is unprecedented and a real success,” the spokesman said.
On April 28, just two days before the government’s deadline, only 52,429 daily tests had been carried out, barely half the target.
That same evening, the hospital staff at Imperial College Healthcare N.H.S. Trust — a network made up of five major hospitals in north and west London — had received a frantic email calling for “at least” 1,500 staff to be tested over the next 48 hours, even if they had no symptoms.
This was far more tests than the government had previously asked hospitals to conduct as part of a pilot study to understand coronavirus prevalence in hospitals, documents show. It also came with a new deadline of April 30, which coincided with the government’s own.
“It’s clear someone has said ‘We need to meet this target in two days’ time,’” said Dr. Gardiner. “The fastest way is not to send round test kits, but to go to a site where lots of people are still working. That’s obviously a hospital.”
Staff members were blindsided, but the hospitals quickly responded, testing more than 2,000 workers by the following day, internal emails show. The day after that, the government hit its target.
But problems quickly emerged at hospital labs across the country. The chemical reagent stocks the government had promised to replenish were not delivered in their weekly allocation. Some received significantly less than they had asked for while others received none, several lab managers said.
One senior lab manager, who helped coordinate the rush testing at the Imperial College network, said they were initially asked to carry out up to 800 tests over 48 hours, but that was ramped up to 2,600. To do this meant labs had to risk exhausting their reagents rather than keeping supplies in hand for the following week’s tests, said the manager, who spoke on condition of anonymity because the N.H.S. forbids speaking publicly without permission.
The next week, the government provided the manager’s labs with 15 percent fewer test kits than needed — but other labs had fared far worse, the manager said, with reagent stocks at several London hospitals “semi-decimated.”
In one case, the manager donated the lab’s entire remaining stock of 196 test kits to South West Pathology, a lab network where the managers said one hospital had run out of reagents entirely after ramping up their testing before the government deadline.
Last week, the British news outlet The Independent reported on a leaked email from South West Pathology that said one of its London hospitals had been forced to restrict testing to symptomatic patients and staff, because of a shortage of chemical reagents — on the same day that Boris Johnson announced the new 200,000 test target.
South West Pathology said in a statement that it was continuing to offer a “comprehensive” testing service for all symptomatic patients and workers at all its hospitals.
Mr. Wilson, president of the Institute of Biomedical Sciences, said he had heard anecdotal evidence about reagent shortages “across the country” since the government passed its 100,000 target. Last week, one lab in the Midlands only received a fifth of the reagents it was expecting to get from the government, he said.
Further north, a network of labs held an emergency meeting on Monday, because they had not received a large enough allocation of reagents to carry out the tests asked of them. One senior lab manager said that her own lab had only received 300 kits, compared with 1,200 at peak supply, and that their biggest lab did not receive any stocks.
“It’s the biggest reagent shortage by a significant mile that we’ve had since the outbreak, and it’s at least partly due to the 100,000 test target,” said the manager in the north, speaking on condition of anonymity because she did not have permission to discuss the matter publicly.
N.H.S. England said that its labs had successfully expanded daily testing capacity and that all labs worked together to share, “where necessary,” the supplies needed to process coronavirus tests.
A leaked briefing document shows that N.H.S. labs were running at around 75 percent capacity over three days last week — while central labs run by Public Health England, an arm of the government, were running at around 65 percent capacity.
The biggest fear for health care workers is that testing to meet a target could lead to shortages of supplies which leave the sickest and most vulnerable without a test when they need it.
“It’s dangerously arbitrary,” said Dr. Gardiner, who added: “We’ve met this one target and it’s given the perception to the public that we’re doing enough on testing, when clearly we are not.”