The UK government has promised it will dramatically increase coronavirus testing to 100,000 a day by the end of the month.
It has been criticised for not testing more people already, as countries like Germany have managed to reach 50,000 tests a day.
Daily coronavirus testing passed 10,000 people a day across the UK on Thursday 2 April – so how can capacity be increased tenfold in just four weeks?
What's stopping the UK testing more people?
There are lots of different pieces to the puzzle when it comes to making large-scale testing work.
You need the laboratory space as well as enough, and the right kind of, machines.
You need the right reagents – highly specific substances used to extract the virus's genetic material and to make it easier to study.
You need staff to take the swabs from patients' noses or throats, and staff in labs to process the tests.
And you need the logistics in place to get samples from patients to labs.
We're talking about diagnostic tests to find out if you have the virus here – ones that involve a nose or throat swab that has to be sent off to a lab.
Antibody tests use blood to look for evidence you've already had the virus – but these are unlikely to be available on a large enough scale in time to be part of the 100,000 target.
Are these problems being addressed?
At first, only a small number of public health laboratories were being used to do coronavirus tests.
In the past fortnight, this was extended to a further 40 NHS labs around the UK.
Now the government is saying it will start to use the lab capacity of private companies to carry out coronavirus tests.
The UK has a large pharmaceutical and biomedical industry whose capacity could "easily" allow the country to do many more tests than it is now, according to Dr Rupert Beale, who has been involved in developing a diagnostic test for coronavirus at the Francis Crick Institute, which will be made available to NHS staff in the area. But so far, this industry hasn't been tapped into, he said.
As well as labs, Health Secretary Matt Hancock said the government would now call on UK-based "pharmaceutical giants" GlaxoSmithKline and AstraZeneca to make the reagents necessary to carry out the tests.
The UK has faced problems getting hold of the relevant reagents, which have been in high global demand.
This has been a global problem, but some countries were in a better position than others.
Could the UK have increased testing sooner?
The decision was made to centralise the UK's testing effort to a small number of public health labs, and this position only began to shift in the last couple of weeks.
Part of being able to scale up means "being willing to cede a little control over where, how and by whom the tests are conducted in order to increase capacity and decrease turnaround times", according to Prof Eleanor Riley, an immunologist at the University of Edinburgh.
The two countries seen as the biggest testing success stories, Germany and South Korea, made many more labs available from an earlier stage – three times as many in Germany and two-thirds more in South Korea when adjusted for population size.
There has also been a question of the availability of testing kits, including the reagents needed to study the virus once on a swab.
While some components have been in short supply worldwide, South Korea acted faster than the UK in developing a test, and was able to stockpile materials.
Germany benefited from home-grown diagnostics and manufacRead More – Source