The health secretary, Matt Hancock, has urged members of the public to carry on as normal “for now”, despite the prime minister saying there could be a “very significant expansion” of the number of cases of coronavirus in the UK.

Hancock said it would not be effective to close schools and offices and cancel large-scale public sporting events to try to contain the virus, but that the government was bulk-buying “respiratory kits” to be used at home if hospitals become overwhelmed.

“We are saying to schools: do not close if you do not have a positive case and if you don’t have the advice from Public Health England,” Hancock told Radio 4’s Today programme. “It would be ineffective and wouldn’t make any difference on clinical grounds. But of course it would also be disruptive.”

Q&A How can I protect myself and others from the coronavirus outbreak? Show Hide The World Health Organization is recommending that people take simple precautions to reduce exposure to and transmission of the coronavirus, for which there is no specific cure or vaccine. The UN agency advises people to: Frequently wash their hands with an alcohol-based hand rub or warm water and soap

Cover their mouth and nose with a flexed elbow or tissue when sneezing or coughing

Avoid close contact with anyone who has a fever or cough

Seek early medical help if they have a fever, cough and difficulty breathing, and share their travel history with healthcare providers

Advice about face masks varies. Wearing them while out and about may offer some protection against both spreading and catching the virus via coughs and sneezes, but it is not a cast-iron guarantee of protection Many countries are now enforcing or recommending curfews or lockdowns. Check with your local authorities for up-to-date information about the situation in your area. In the UK, NHS advice is that anyone with symptoms should stay at home for at least 7 days. If you live with other people, they should stay at home for at least 14 days, to avoid spreading the infection outside the home.

He said the government’s goal was “to have the minimum social and economic disruption, subject to keeping people safe. So what we are saying right now is that as long as you follow the advice from Public Health England – wash your hands more often than you would, for 20 seconds and use soap and hot water – then you should carry on your ordinary business as normal.”

The government publishes its official action plan on Tuesday for dealing with the virus. Under the “reasonable worst-case scenario” plotted by scientists, it would take several weeks before the number of cases rose to epidemic level, Hancock said, “and then it would be a matter of months until we are through it”.

The chief medical officers of England, Wales, Scotland and Northern Ireland will advise the government on when to take more direct action, taking into consideration what other countries are doing to stop the spread. “If the rest of the world gives up on containing it then there’s no way that one country, even an island like the UK, will be able to resist,” Hancock told Radio 4, breaking the government’s recent boycott of the show.

He said all employees were entitled to statutory sick pay if they had to self-isolate at home. “We have a statutory sick pay system in this country and self-isolating for medical reasons if you are healthy counts as being sick in the legislation,” he said.

Freelancers and self-employed workers could apply to the Department for Work and Pensions “if they get into difficulty”.

Hancock said emergency legislation would make it easier to recall retired doctors and other health workers to plug gaps in hospitals and GP surgeries, “also so we can get volunteers more easily into the NHS and social care”. He said he accepted that more patients would need to be cared for at home instead of in hospital if the worst-case scenario came about and 2 million people needed treatment.

“Should the figures end up as big as that we will have to do things differently. For instance, much more care at home. And anyway, with an infectious disease, home is often the best place, especially for a disease that appears to have a relatively mild impact for most people,” he said. “But of course some people will need support at home. For instance, we are currently in the middle of buying respiratory kits that can be used out of hospital at home.”

Talking on BBC Breakfast, Hancock said officials may have to look at restricting participation in the London Marathon because of the coronavirus outbreak but it was “far too early” to make any decisions.

He told Today: “The message today is that, right now, we do not need to do many of the heavy things we are talking about in the plan. but we are also setting [them] out as transparently as we possibly can so people know the sort of things we might have to do in future.”