(Source BBC News)
The UK government wants to do 100,000 coronavirus tests a day by the end of April, but has faced criticism for not increasing the number more quickly. By mid-April, 21,000 tests were being conducted a day, on 14,000 people.
So what are the tests and why has it been difficult to do more?
The tests currently being used in UK hospitals are to see if somebody currently has Covid-19. They are being carried out in hospitals and at 27 drive-through testing centres across the country.
These are done by taking a swab of the nose or throat, which is sent off to a lab to look for signs of the virus's genetic material.
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