Chinese health officials have released the first details of more than 44,000 cases of new coronavirus, Covid-19, in the largest study since the outbreak began.
Data from the Chinese Centre for Disease Control and Prevention (CCDC) finds that more than 80% of the cases have been mild, with the sick and elderly most at risk.
The research also points to the high risk to medical staff.
On February 18, a hospital director in the city of Wuhan died from the virus.
Liu Zhiming, 51, was the director of the Wuchang Hospital in Wuhan – one of the leading hospitals in the virus epicenter. He is one of the most senior health officials to die so far.
Hubei, whose capital is Wuhan, is the worst affected province in China.
The report by the CCDC shows the province’s death rate is 2.9% compared with 0.4% in the rest of the country.
The findings put the overall death rate of the coronavirus at 2.3%.
China’s latest official figures released on February 18 put the overall death toll at 1,868 and 72,436 infections.
Officials reported 98 new deaths and 1,886 new cases in the past day, with 93 of those deaths and 1,807 infections in Hubei province – the epicenter of the outbreak.
According to Chinese authorities, more than 12,000 people have recovered.
The study, published in the Chinese Journal of Epidemiology on February 17, looked at more than 44,000 confirmed cases of Covid-19 in China as of February 11.
While the results largely confirm previous descriptions of the virus and patterns of infection, the study includes a detailed breakdown of the 44,672 confirmed cases across all of China.
The study finds that 80.9% of infections are classified as mild, 13.8% as severe and only 4.7% as critical. The number of deaths among those infected, known as the fatality rate, remains low but rises among those over 80 years old.
Looking at the sex ratio, men are more likely to die (2.8%) than women (1.7%).
The research also identifies which existing illnesses put patients at risk. It puts cardiovascular disease at number one, followed by diabetes, chronic respiratory disease and hypertension.
Pointing out the risk to medical staff, the study says that a total of 3,019 health workers have been infected, 1,716 of which were confirmed cases. Five had died by February 11, which was the last day of data included in the research.
On February 13, China broadened its definition of how to diagnose people, including “clinically diagnosed cases” which previously were counted separate from “confirmed cases”.
Looking forward, the study finds that “the epidemic curve of onset of symptoms” peaked around January 23-26 before declining up to February 11.
It suggests that the downward trend in the overall epidemic curve could mean that “isolation of whole cities, broadcast of critical information (e.g., promoting hand washing, mask wearing, and care seeking) with high frequency through multiple channels, and mobilization of a multi-sector rapid response teams is helping to curb the epidemic”.
The authors also warn that with many people returning from a long holiday, the country “needs to prepare for the possible rebound of the epidemic”.
China’s response to the new coronavirus has seen the lockdown of Wuhan – the largest city in Hubei – and the rest of the province as well as severe travel restrictions on movements across the country.
The coronavirus causes severe acute respiratory infection and symptoms usually start with a fever, followed by a dry cough. Most people infected are likely to fully recover – just as they would from a flu.
Hong Kong Chief Executive Carrie Lam said anyone arriving from the mainland, including foreigners, would be quarantined for 14 days from February 8, although she did not say how this would be imposed.
It is unclear where the quarantines would take place or whether Hong Kong residents could spend the time at home.
Tens of thousands of people arrived from the mainland on February 4.
Carrie Lam has not moved to close the border entirely, although thousands of medical staff on February 5 entered the third day of their strike over the issue and have threatened to escalate their action.
Hong Kong will, however, close the Ocean and Kai Tak cruise terminals.
Some 3,600 passengers and crew on the World Dream, docked at Kai Tak, are being tested for the virus after three Chinese passengers who were on the ship between January 19 and 24 tested positive after disembarking.
Hong Kong remains concerned about a repeat of the deadly Severe Acute Respiratory Syndrome (SARS) outbreak, although the mortality rate of the new virus is much lower than that of SARS, which was around 9.6%.
There have been massive queues for masks which are in short supply and are selling at inflated prices.
Separately, the Hong Kong-based airline Cathay Pacific is asking 27,000 staff to take three weeks unpaid leave over the coming months as it deals with the impact of the outbreak.
In a public statement on January 31, Health Secretary Alex Azar said US citizens returning from Hubei province would face 14 days of quarantine while those returning from other parts of China would be allowed to monitor their own condition for a similar period.
He told reporters: “Following the World Health Organization decision, I have today declared that the coronavirus represents a public health emergency in the United States.”
Citing the need to relieve pressure on authorities, Alex Azar said that foreign nationals who had travelled in China in the past two weeks would be denied entry to the US.
He added: “The risk of infection for Americans remains low and with these, and our previous, actions we are working to keep the risk low.”
Another confirmed case in the US on January 31 – in California – brought the number there to seven. Robert Redfield, director of the Centers for Disease Control and Prevention (CDC), said 191 people were under observation for the disease.
The US announcement came as other countries around the world scrambled to contain the spread of the new virus, 2019-nCov.
On January 31, the UK confirmed its first two cases.
Estimates by the University of Hong Kong suggest the true total number of cases could be far higher than official figures suggest. Based on mathematical models of the outbreak, experts there say more than 75,000 people may have been infected in the city of Wuhan alone, where the virus first emerged.
Most cases outside China involve people who have been to Wuhan. Germany, Japan, Vietnam, the US, Thailand and South Korea have reported person-to-person cases – patients being infected by people who had travelled to China.
Meanwhile in Wuhan, voluntary evacuations of hundreds of foreign nationals are under way.
Australia, South Korea, Singapore, New Zealand and the UK are expected to quarantine all evacuees for two weeks to monitor them for symptoms and avoid contagion.
The spread of the deadly coronavirus is accelerating, Chinese President Xi Jinping warned, after holding a special government meeting on the Lunar New Year public holiday.
China is facing a “grave situation” President Xi told senior officials.
The new virus has killed at least 56 people and infected almost 2,000 since its discovery in the city of Wuhan.
Meanwhile, the US has announced that staff at the Wuhan consulate will be evacuated on a special flight on January 28.
According to the State Department, private Americans most at risk will also be able to board the flight to San Francisco.
Meanwhile, UK-based researchers have warned of a real possibility that China will not be able to contain the virus.
Travel restrictions have come in place in several affected cities. From January 26, private vehicles will be banned from central districts of Wuhan, the source of the outbreak.
According to Chinese state newspaper the People’s Daily, a second emergency hospital is to be built there within weeks to handle 1,300 new patients, and will be finished in half a month. It is the second such rapid construction project: work on another 1,000-bed hospital has already begun.
Specialist military medical teams have also been flown into Hubei province, where Wuhan is located.
The urgency reflects concern both within China and elsewhere about the virus which first appeared in December.
Lunar New Year celebrations for the year of the rat, which began on January 25, have been canceled in many Chinese cities.
Across mainland China, travelers are having their temperatures checked for signs of fever, and train stations have been shut in several cities.
Hong Kong has declared the highest level of emergency and school holidays were extended.
Several other nations are each dealing with a handful of cases, with patients being treated in isolation.
A coronavirus is a family of viruses which include the common cold.
However, this virus has never been seen before. It is called 2019-nCov, for “novel coronavirus”.
New viruses can become common in humans after jumping across the species barrier from animals.
The SARS [Severe Acute Respiratory Syndrome] outbreak of 2003 started in bats and transferred to the civet cat which passed it on to humans.
This new Chinese virus also causes severe acute respiratory infection.
Symptoms seem to start with a fever, followed by a dry cough and then, after a week, lead to shortness of breath and some patients needing hospital treatment.
There is no specific cure or vaccine.
Based on early information, it is believed that only a quarter of infected cases are “severe”, and the dead are mostly – though not exclusively – older people, some of whom have pre-existing conditions.
The Chinese authorities suspect a seafood market that “conducted illegal transactions of wild animals” was the source of the outbreak.