A third case of the Omicron Covid variant has been confirmed in the UK, officials have said, as Sajid Javid insisted the government is “nowhere near” having to reimpose mandatory social distancing and home working to mitigate the threat it poses. The person who tested positive was linked to previous travel in southern Africa and had left the UK before the result emerged, the UK Health Security Agency said. Targeted testing would take place where the person had been, it said, adding that this was Westminster, in central London, giving no further details. The news came after Javid, the health secretary, described rules announced by Boris Johnson to combat the variant, including compulsory masks on public transport and in shops, as “proportionate and balanced”. Speaking a day after the first UK cases of the new variant were reported, Javid told Sky’s Trevor Phillips on Sunday show that there were no plans for extra restrictions, such as social distancing, wearing masks in pubs or working from home. “We know now that those type of measures do carry a very heavy price, both economically, socially, in terms of non-Covid health outcomes such as the impact on mental health,” Javid said. “If one was to make decisions like that, they would have to be done very, very carefully. We’re not there yet. We’re nowhere near that.” In a subsequent interview with BBC One’s Andrew Marr Show, Javid said he would not advise people to work from home, even if possible, saying: “No, I don’t think that’s necessary.” Such moves would have “a really heavy cost on the economy, on people’s social lives, on their mental health”, he said. While there are concerns that the number of mutations in the Omicron variant might make it resist some Covid vaccines, Javid told Sky that even if this was the case, vaccines were still likely to give some protection. The booster jabs programme, currently limited to people aged 40 or over, or with health vulnerabilities, was to be extended, Javid said. The Joint Committee on Vaccines and Immunisation (JCVI), the government’s vaccines watchdog, had been asked to provide “very quick advice on broadening our booster programme, and I expect to get that advice imminently”, he said. It is understood that the JCVI held an emergency meeting on Saturday, and that officials may make an announcement on Monday. Javid said he was confident that the return of mandatory mask use in England from Tuesday would be respected, despite low compliance rates in places where it has remained compulsory, such as on London transport services. “Over the past few days, people would have been able to see and understand the concerns around this new variant,” he said. “I think that will encourage people to listen and think about some of the new measures, and take them very seriously.” However, the shadow foreign secretary said in an interview with Times Radio that she was concerned about levels of mask use, given the disinclination of Johnson and many other Conservatives to wear them. “You only have to walk around parliament to see the problem,” Lisa Nandy said. “Most Tory MPs don’t wear masks.” Ministers have also imposed travel restrictions since the variant was first identified in South Africa last week, with 10 countries on the red list, requiring mandatory hotel quarantine for people arriving in England, and other UK nations set to follow. Six countries were added to the list from midday on Friday: South Africa, Zimbabwe, Namibia, Lesotho, Botswana and Eswatini. Four more went on at 4am on Sunday: Angola, Malawi, Mozambique and Zambia. Asked if he could guarantee that people would be able to see families and other loved ones at Christmas, Javid said: “You ask me for guarantees and I think it’s fair to say that the nature of this pandemic is that it would be irresponsible to make guarantees. What I can tell you is that the actions we have taken, the proportionate and balanced actions, will buy us time. “It will give us the precious weeks our scientists need to assess this variant. I think people should continue with their plans as normal for Christmas. It’s going to be a great Christmas.” Speaking separately, in an interview with the Mail on Sunday, Javid said he hoped rules to be introduced in spring that will make Covid vaccinations mandatory for frontline NHS and care staff would not cause significant staff shortages. He said: “It’s hard to know. As a country we haven’t done anything like this before. “If I look at other countries ... France did something similar and in three or four months they went from, I think it was something like 70% vaccinated to 99.8% vaccinated. I hope we’ll have a similar response.”