(Bloomberg) -- Steps taken after the discovery of the new coronavirus variant in the U.K. will buy scientists “precious weeks” to evaluate the strain, U.K. Health Secretary Sajid Javid said.

He said the U.K. is still “not there yet” on the need for more draconian steps, which he said “carry a very heavy price” in terms of mental health and other effects. 

Javid spoke on Sky News a day after the U.K. government announced measures to confront the spread of omicron after two cases were identified in people who had traveled from southern Africa. 

It’s unclear if current Covid-19 shots will work as well against the variant, and a rush to produce new or reformulated vaccines is on. 

U.K. Announces New Measures to Confront Spread of Omicron 

Javid said he was confident people will take more seriously mask-wearing rules for crowded places like shops and public transport to start on Tuesday. 

Masks are already required on London transport but the rules are widely ignored. 

“The British public can see why the government has imposed this,” Javid said on BBC’s “Andrew Marr Show.” 

As well as the return of a mask mandate, the U.K. will require anyone entering the country to take a PCR test within two days of arrival and self isolate until they receive confirmation of a negative result. 

Fauci Says He Won’t Be Surprised If Omicron Already in U.S. 

Ten southern African countries are now on the U.K.’s “red list.” People returning from those countries face a mandatory 10-day quarantine at a managed hotel at their own expense.

The latest measures don’t go as far as the government’s Plan B, which includes encouraging people to work from home. 

U.K. coronavirus cases have been running at a high level for months. Even so, a successful vaccination campaign has kept hospitalizations down, and deaths from Covid are a fraction of the peak seen last winter, before the shots became available.   

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