Positive Lateral Flow Tests

LONDON, ENGLAND - DECEMBER 22: In this photo illustration, a series of positive Covid-19 test results are displayed on December 22, 2021 in London, England. People infected with Covid in England can stop self-isolating up to three days early if they test negative twice, it has been announced. They will now be able to end quarantine after seven days instead of 10 by providing negative lateral flow results on day six and day seven. Still, the exploding infection rate threatens to overwhelm the NHS, and may cause staff shortages as NHS workers are forced to quarantine. (Photo illustration by Richard Stabler/Getty Images)