December 23, 2021: The British government has shortened the mandatory Covid-19 self-isolation period in England from 10 days to seven days for those who receive negative lateral flow tests on two consecutive days.

On Wednesday, Health Minister Sajid Javid announced that to minimize disruption and “following expert clinical advice,” those who get a negative lateral flow result on days six and seven of their quarantine period will be allowed to leave isolation.

The U.K. is battling an increase in highly transmissible omicron variant cases, with fears mounting that health services could be overwhelmed and economic activity dented.

Until now, the British government has resisted emulating several countries in mainland Europe that have imposed strict containment measures for the holiday period.

The mandatory isolation period was reduced from 14 days to 10 days in late 2020 as the alpha variant spread in various regions of the U.K., and the quarantine requirement for vaccinated close contacts of positive cases was decreased during the delta wave earlier this year.

On Wednesday, Irene Petersen, professor of epidemiology and health informatics at University College London, told CNBC that shortening the isolation period was a good move since the people are not infectious beyond day seven. The requirement for consecutive negative tests will catch most anomalies.

“I look a little bit on the sensitivity of that, and if you say a single test has a sensitivity of nearly 90%, if you combine the sensitivity of the two tests, you are up at 99%, and that means we will have few who would be false negative,” she said.

“Also, taking into consideration that we only have, let’s say, 10% are still infectious at that time, it would be less than one in 1,000 people who would be false negative after that. So I think it is a sensible move right now to cut it to seven days.”

The U.K. government also announced Wednesday that it had signed two contracts for a combined 4.25 million courses of Covid-19 antiviral pills.

Pfizer announced Wednesday that it will provide an additional 2.5 million doses of its COVID-19 pill Paxlovid to the country, with a total of 2.75 million due to be delivered throughout 2022.

The British government has ordered 1.75 million additional courses of Merck Sharp and Dohme’s Lagevrio pill, with both options that are expected to be effective against omicron in reducing the risk of hospitalization and death in high-risk patients.