The government has announced 16 areas where there is still “high availability” for coronavirus site tests after running out of home kits on Wednesday morning in just an hour.
There was a rush for home tests after millions of more people were eligible to book on the government website from 8am.
Health secretary Matt Hancock announced on Tuesday that care home residents and staff together with NHS patients and staff can now get a test whether they have symptoms or not.
Older people over the age of 65 plus anyone in their households are also eligible, but only if they have symptoms.
Tests at regional drive-through centres ran out in Wales almost immediately but were still available in England, Scotland and Northern Ireland as of 11.30am.
The Department of Health has confirmed there is still “high availability” of tests in some drive-through centres.
These include Brighton, Bournemouth, Bristol, Ebbsfleet, Exeter, Gatwick, Hull, Ipswich, Lincoln, Manchester, Oxford, Peterborough, Penrith, Plymouth, Stansted and York.
The public can book tests through the government website here.
National testing coordinator Professor John Newton told LBC on Wednesday people who fit the criteria should only apply for tests if they have COVID-19 symptoms.
He said: “This is for people who are unwell with coronavirus symptoms, and their households... it's not a screen.”
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He added he was confident the 100,000 daily targets for coronavirus tests will be met on Thursday.
Prof Newton, director of public health improvement for Public Health England (PHE), told BBC Radio 4’s Today programme: “We are pretty confident we will hit that target. It puts us really right up there with countries like Germany, so we need that now but we need that for the future as well.”
There will be a lag in receiving the data but “by the end of the week we will know whether we have reached that target”, he added.
Hancock’s announcement on Tuesday of the massive testing expansion came after the government has been under pressure over the target.
PHE has also come under fire for abandoning contact tracing in mid-March, saying at the time that the spread of the virus through the population made continuing such a method unfeasible.