Hong Kong reported its first death from the coronavirus and four major Chinese cities hundreds of miles from the centre ordered lockdowns as concerns about the spread of the disease mounted.

The country’s leadership admitted “shortcomings” in its handling of the outbreak, with the number of infections and deaths still mounting daily. The death toll inside China has passed 420 and Britain has advised its citizens to leave the country.

A 39-year-old man with an underlying health condition died in Hong Kong on Tuesday morning, according to the public broadcaster RTHK.

His death is the second outside the mainland after a Chinese national from Wuhan was confirmed on Sunday to have died in the Philippines.

China announced 64 more deaths on Tuesday – surpassing Monday’s record to confirm the biggest daily increase since the virus was detected late last year in the central province of Hubei.

Quick guide What are coronavirus symptoms and should I go to a doctor? Show Hide What is Covid-19? Covid-19 is caused by a member of the coronavirus family that has never been encountered before. Like other coronaviruses, it has come from animals. The World Health Organization (WHO) has declared it a pandemic. What are the symptoms this coronavirus causes? According to the WHO, the most common symptoms of Covid-19 are fever, tiredness and a dry cough. Some patients may also have a runny nose, sore throat, nasal congestion and aches and pains or diarrhoea. Some people report losing their sense of taste and/or smell. About 80% of people who get Covid-19 experience a mild case – about as serious as a regular cold – and recover without needing any special treatment. About one in six people, the WHO says, become seriously ill. The elderly and people with underlying medical problems like high blood pressure, heart problems or diabetes, or chronic respiratory conditions, are at a greater risk of serious illness from Covid-19. In the UK, the National health Service (NHS) has identified the specific symptoms to look for as experiencing either: a high temperature - you feel hot to touch on your chest or back

a new continuous cough - this means you’ve started coughing repeatedly As this is viral pneumonia, antibiotics are of no use. The antiviral drugs we have against flu will not work, and there is currently no vaccine. Recovery depends on the strength of the immune system. Should I go to the doctor if I have a cough? Medical advice varies around the world - with many countries imposing travel bans and lockdowns to try and prevent the spread of the virus. In many place people are being told to stay at home rather than visit a doctor of hospital in person. Check with your local authorities. 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.

The virus has killed at least 426 people, exceeding the 349 mainland deaths from the severe acute respiratory syndrome (Sars) outbreak of 2002-03, which killed nearly 800 globally.

The total number of infections in China also rose, to more than 20,000. The World Health Organization (WHO) has declared the crisis a global health emergency, with at least 151 cases in 23 other countries and regions.

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The vast majority of cases are still concentrated in and around Wuhan, the Hubei provincial capital, which has been on lockdown for nearly two weeks. But with increasing numbers of infections registered in other parts of China, some of the worst-hit areas are also bringing in radical measures.

Several cities in Zhejiang, a coastal province with a strong trade and manufacturing heritage, have shut schools, businesses, markets and shopping centres, cut off most public transport and barred residents from leaving their homes except to buy necessities or seek medical treatment.

The coastal city of Wenzhou, hundreds of miles east of Wuhan, was the first to bring in “special measures”, Reuters reported. On Sunday it had 291 confirmed cases of coronavirus, the highest number of any city outside Hubei.

Since then the city of Taizhou, and several districts in the cities of Ningbo and historic Hangzhou have also been locked down. They include the base of the Chinese tech giant Alibaba, city officials said.

The virus is taking an increasing economic toll, shutting businesses, curbing international travel and affecting production lines of global brands.

China’s currency and stock markets steadied in choppy trade after anxiety over the virus hit the yuan on Monday and erased about £308bn in market value from Shanghai’s benchmark index. Macau, the world’s biggest gambling hub, said it had asked all casino operators to suspend operations for two weeks to help curb the spread of the virus.

Wuhan, a bustling industrial hub where the virus first infected humans, has been turned into a near ghost town as a de facto quarantine continues.

Residents say they are unable to find hospitals to care for their sick relatives. Several hospitals require patients to first get a referral from local community health centres, many of which are also overwhelmed. As the city remains under lockdown, with public transport and roads shut, people are also struggling to get to health facilities.

Authorities have been racing to build two hospitals to treat the infected. The first of those – a 1,000-bed facility – began to receive patients on Monday, the People’s Daily reported, only 10 days after construction began. A second hospital is due to open this week.

Authorities in Wuhan have also started converting a gymnasium, exhibition centre and cultural complex into makeshift hospitals with more than 3,400 beds for patients with mild infections, the official Changjiang Daily said.

As the crisis has developed, people from Wuhan and Hubei have faced increasing discrimination in other parts of the country. Many say they have been kicked out or turned away from hotels.

Passengers on a flight from Japan to Shanghai in late January reportedly refused to board a flight that had passengers from Wuhan on it. Neighbourhood committees have placed signs on the doors of those recently returned from the province advising other residents not to visit them.

Experts say much is still unknown about the pathogen. The mortality rate for the new coronavirus is lower than the 9.6% rate for Sars, but it appears to be more contagious. Reports of deaths not counted in official statistics have also cast doubt on the mortality rate.

Such uncertainties have spurred extreme measures by some countries to stem the spread. On Tuesday the UK urged all its citizens to leave China if they can, while Australia sent hundreds of evacuees to a remote island in the Indian Ocean, and Japan ordered the quarantine of a cruise ship with more than 3,000 onboard after a Hong Kong man who sailed on it last month tested positive for the virus.

France recommended that its citizens – particularly those with families – should leave China “temporarily,” and recommended against all but “essential” travel to the country.

There have been 15 confirmed cases in Hong Kong, where authorities announced new border closures after hundreds of medical workers went on strike on Monday over the government’s refusal to stop travellers from mainland China.

Late on Monday, China’s elite Politburo Standing Committee called for improvements to the “national emergency management system” following “shortcoming and difficulties exposed in the response to the epidemic”.

The Chinese president, Xi Jinping, who led the meeting, said the outbreak was a “major test” of China’s system and ability to govern.