Since last weekend the UK government has failed to meet its target of providing 100,000 coronavirus tests per day.
This goal was set for the end of last month and the government said 122,347 tests were provided across the UK on 30 April.
It was criticised for including in this figure around 40,000 testing kits which are counted when they are sent out rather than when they are actually used.
The target was also met on 1 May but was missed for eight consecutive days after that.
On 10 May, 100,490 tests were carried out on 65,337 people (this figure is lower as some people need more than one test).
On 6 May, the Prime Minister announced a fresh target to get to 200,000 tests a day by the end of May “and then to go even higher”.
Statistical regulator the UK Statistics Authority has written to Health Secretary Matt Hancock to ask for clarification of whether that target is for testing capacity, the number of tests administered, the number of tests completed or the number of people tested.
Why was the 100,000 target set?
Some, including NHS leaders, have suggested the reasoning behind the particular figure was unclear.
Health Secretary Matt Hancock said after the target had been reached that the “ambitious” goal had been designed to have a “galvanising effect”.
Prof John Newton of Public Health England added: “We knew from our calculations that we would need something like this level of testing to be ready for the next phase of the response to the pandemic.”
The UK significantly increased its testing capacity over the past month, although it lags behind many other nations. Germany, for example, was regularly averaging 100,000 tests a day by the start of April.
Who can get tested?
At first, across the UK, the focus was on the sickest patients in hospitals, followed by health, care and emergency services staff, then other essential workers and their families.
Most recently in England, testing has been expanded to include anyone with symptoms who is:
- over 65
- cannot do their work from home
- living with those identified above
There have been serious problems containing the outbreak in care homes. After weeks of lockdown, it was announced that residents and staff of care homes in England could be tested even if they don’t have symptoms.
Key workers across the UK who are self-isolating because they or a family member have coronavirus symptoms can be referred for a test by their employer or apply online.
If a test is negative, a key worker can return to work if they are well enough, have not had a high temperature for 48 hours, and those living with them test negative.
How do the tests work?
The tests are done by taking a swab of the nose or throat, which is sent to a lab to spot signs of the virus’s genetic material.
Those eligible can either attend a regional test site, or ask for a home test kit – although these have been in short supply.
The British Medical Association had said the accessibility of centres was a major problem, with some people having to drive hundreds of miles to their nearest site – especially difficult for people suffering symptoms of Covid-19.
The government has also admitted sending about 50,000 coronavirus tests to the US last week for processing after “operational issues” in UK labs.
The Department of Health said sending swabs abroad is among the contingencies to deal with “teething problems”.
Why is testing important?
People are tested to diagnose them individually, but it can also be used to understand how far the virus has spread in the population.
For this second reason, a total of 20,000 households in England will be tested every month for a year – for active coronavirus infections and for antibodies indicating a past infection.
It also helps people, including NHS workers, know whether they are safe to go to work. It can enable the health service plan for extra demand, and inform government decisions around social distancing and lockdowns.
Has the UK been too slow in testing for coronavirus?
The UK did not start with the resources to do mass testing, unlike some other countries. It also took several weeks to expand from an initial eight public health laboratories to a wider network of private and university labs.
Unlike the UK, countries like Germany and South Korea rapidly stockpiled kits and made the test available to a larger number of labs.
As of 29 April, the UK had carried out 8.83 tests per 1,000 people, whereas Italy had done 31.6 per 1,000, Germany 30.4 (as at 26 April) and South Korea 11.98, according to data collated by online scientific publication Our World in Data from official sources.
What about antibody tests?
An antibody test shows whether someone has already had the virus.
They work by looking for signs of immunity, by using a drop of blood on a device that works a bit like a pregnancy test.
No home antibody test has yet proved to be reliable enough to be used.
A more reliable antibody test is in use at the government’s Porton Down laboratory, but it is currently being reserved to estimate population-level immunity – not to give individuals information about their infection status.
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