Sports events and concerts may have to be cancelled and schools closed for more than two months if the UK is hit by a global pandemic of coronavirus, the chief medical officer has warned.

Prof Chris Whitty said the country should prepare to face disruption to many normal activities “for quite a long period” and to pay a heavy “social cost” for efforts to thwart the virus.

The NHS may have to cancel planned operations during the peak of a major outbreak to free up beds and staff for patients with coronavirus, he said, adding that the service would find it “quite tricky” to deal with a huge increase in the number of cases.

Whitty’s remarks, which came as the first case in Northern Ireland was confirmed, are the most explicit acknowledgement yet by top officials working to stop the spread of Covid-19 that the small number of cases recorded in the UK – 16 and no deaths so far – could yet escalate dramatically, depending on how the virus progresses internationally.

If sport is affected, that could pose problems for major events, such as the closing stages of the Premier League season and rugby’s ongoing Six Nations tournament. Ireland’s Six Nations match against Italy that was due to be played in Dublin on Saturday has already been called off because of the recent outbreak of coronavirus in Italy, where there have been more than 650 confirmed cases and 17 deaths.

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Speaking to an audience of health experts at a Nuffield Trust thinktank conference, Whitty, who is the government’s chief medical adviser, outlined steps that may be taken if the coronavirus becomes a pandemic.

“Everybody knows that the kinds of things you consider – reducing mass gatherings, school closures, which may or may not be appropriate for this particular virus. We don’t know yet. We need to find that out.

“Now, to be clear, we’re not saying we will do them, but we have to look at all of them and say: how likely are they to work? And what’s our evidence base here? What’s the social cost of this?

“Because one of the things, frankly, with this virus much more so than flu, is whatever we do we’re going to have to do for quite a long period of time, probably more than two months. And the implications of that are non-trivial. So we need to think that through.”

He added: “This is something we face as really quite a serious problem for society potentially if this goes out of control. It may not, but if it does globally, then we may have to face that.”

Ministers are finalising the government’s plan to respond to the increasing threat posed by coronavirus, which is expected to be published next week. Matt Hancock, the health secretary, insisted: “There is a good chance that we can avoid a pandemic. That’s a potential outcome but not a definite outcome.”

Hancock sought to reassure the public that the NHS would be able to cope with a sudden surge in cases by stressing that it had well laid plans based on a detailed document drawn up in 2011, which sets out measures that would be implemented in a flu pandemic.

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 also rebuffed a suggestion that Boris Johnson should become more visible in order to reassure the public about coronavirus. Hancock, who chairs a weekly meeting of the Cobra committee from several government departments, said that a regular “drumbeat of Cobra meetings and meetings with the prime minister and meetings of the cabinet” showed the political priority that the virus was getting.

Britain will inevitably record more cases than the 16 identified so far, Whitty said. He said that onward transmission in the UK was “just a matter of time in my view. If it is something which is containable, the UK can contain it. If it is not containable, it will be non-containable everywhere and then it is coming our way.”

The strategy to minimise the virus’s impact is based on four tactics: containing its spread, delaying onward transmission, researching its makeup and possible treatments, and mitigating its effect on the NHS.

The hope is to contain the virus for as long as possible and try to delay the peak of any major outbreak until the early summer, when warmer weather is expected to result in a drop in the number of cases, as with influenza.

However, Whitty said thousands of non-urgent operations would be delayed if the NHS had to concentrate its resources on dealing with the virus.

While the virus presented “some challenges”, the world was not facing a threat as deadly as the Spanish Flu outbreak in 1918, Whitty added. That is thought to have claimed 50 million lives worldwide.

“Occasionally things come along which, no matter how good your strategic aim is, will knock you off course for a while. We are not heading into a H1N1 1918 flu pandemic situation, but the coronavirus does present some challenges for us. It definitely will for a period. How big remains to be seen,” he said.

His remarks came as Public Health England (PHE) said it had sent a health protection specialist to the H10 Costa Adeje Palace hotel in Tenerife, where four former guests tested positive for the virus and 168 Britons were among more than 700 people placed in quarantine. According to reports, 50 of the Britons quarantined at the hotel were allowed to leave on Thursday.

PHE is due to launch a major public information campaign next week to educate people about how to minimise the risks of contracting or spreading the virus. Whitty stressed that regular handwashing remained the single best way of reducing risk.

Experts in infectious diseases said that the two new cases identified in the UK early on Thursday were not a cause for concern and that the measures deployed in Britain so far – including isolating confirmed cases and tracing people they have been in touch with – were working. The Northern Irish case, in a patient who had recently returned from Italy, was confirmed later in the day.

“There is no due cause for alarm,” said Prof Brendan Wren of the London School of Hygiene and Tropical Medicine.

Dr Tom Wingfield, from the Liverpool School of Tropical Medicine, added: “There are likely to be some more cases in the coming weeks but the UK public can be reassured that we have experienced teams in place to manage the isolation and care of people diagnosed with coronavirus and perform robust tracing and screening of their contacts.”