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What Is the Coronavirus? Symptoms, Treatment and Risks The Wuhan Coronavirus: Symptoms, Treatments and Science
(about 13 hours later)
An international outbreak of respiratory illness caused by a novel coronavirus has killed at least 300 people and sickened about 14,000, according to the Chinese health authorities. A respiratory virus that is so new it does not yet have a name has spread quickly from Wuhan, China, leaving many experts to fear what may become a pandemic of pneumonialike illness.
The outbreak began in Wuhan, China, apparently at a market selling live poultry, seafood and wild animals. Now the virus has turned up in about 20 other countries, including Japan, South Korea, France, Australia and the United States. Investigators in still other nations, and in several American states, are evaluating possible cases. So far, the virus — a coronavirus whose scientific designation is 2019-nCoV — has spread to at least 23 countries, infecting more than 17,000 people and killing at least 360. Most of the cases, so far, have been in China.
The World Health Organization has declared a global health emergency over the spread of the virus. Officials in China have effectively cordoned off 50 million people in the region surrounding Wuhan. Russian has closed much its border with China, and several nations have begun imposing travel restrictions and quarantines on passengers arriving from China. But the Wuhan coronavirus may be highly transmissible, as contagious as seasonal influenza, and the death rate is still unknown.
Eight cases have been confirmed in the United States. Federal health officials have told Americans not to visit the China unless necessary. Airlines are cutting back on flights to the nation. The World Health Organization has estimated that one in every 50 infected individuals will die, and medical reports suggest the new virus can be transmitted even before an infected individual displays symptoms — a combination of factors that, if accurate, will make it nearly impossible to contain.
But much is still unknown about the newly identified virus, including how easily it is transmitted and how often it causes severe disease that can lead to death. Last week the W.H.O. declared a global public heath emergency, and made plans to dispatch experts to China to help with the investigation and containment.
One of the key questions is whether it can be transmitted by patients who have not yet shown any symptoms of illness themselves. If that is the case, the outbreak will be difficult to contain and may become a pandemic. The United States also declared a public health emergency and has offered assistance, and is barring entry by most foreign nationals who have visited China recently. American travelers returning from trips in the Wuhan/Hubei region will be quarantined for two weeks.
The outbreak appears to have begun at a seafood and meat market Wuhan. Since then it has spread to other parts of China, and turned up in other countries in Asia and in Australia, Europe and North America.
Chinese authorities cordoned off Wuhan days before the Lunar New Year holiday, suspending transportation in and out of the provincial seat of Hubei and other affected cities, closing in an estimated 50 million people.
Federal health officials are urging Americans to avoid all travel to China, and have quarantined 195 Americans evacuated from Wuhan for 14 days.
“This is a very serious public health situation, and the C.D.C. and federal government have and will continue to take aggressive action to protect the public,” said Dr. Nancy Messonnier. The quarantine of a planeload of American evacuees in Southern California was an “unprecedented action,” she added, provoked by an “unprecedented threat.”
As of Monday, 11 cases have been confirmed in the United States, most of them in patients who had traveled to China. One patient who had not traveled was apparently infected by his wife when she returned from China. More than 100 other patients in the United States are being tested.
Experts cannot yet say who is at greatest risk for developing severe or life-threatening disease, and what factors may be protective against the illness.
Here’s what we have learned so far about the virus and the outbreak.Here’s what we have learned so far about the virus and the outbreak.
Coronaviruses are named for the spikes that protrude from their membranes, which resemble the sun’s corona. They can infect both animals and people, and can cause illnesses of the respiratory tract, ranging from the common cold to dangerous conditions like Severe Acute Respiratory Syndrome, or SARS, which sickened thousands of people around the world — and killed nearly 800 — during an outbreak in 2003. Coronaviruses are named for the spikes that protrude from their membranes, which resemble a crown or the sun’s corona. They can infect both animals and people, and can cause illnesses of the respiratory tract. The infections can range from the common cold to dangerous conditions like Severe Acute Respiratory Syndrome, or SARS, which sickened thousands of people around the world — and killed nearly 800 — during an outbreak in 2003. Middle East Respiratory Syndrome, or MERS, first reported in Saudi Arabia in 2012, is also caused by a coronavirus.
Health officials around the world are alarmed, but it is hard to accurately assess the lethality of a new virus. It is hard to accurately assess the lethality of a new virus, and some scientists said initially that the new virus appeared to be less severe than other coronaviruses, like SARS or MERS.
“When we get a new infectious disease, we learn about the most severe cases first, the top of the pyramid as it were,” said Dr. William Schaffner, a professor of preventive medicine and infectious diseases at Vanderbilt University Medical Center. But recent news reports indicate the Chinese authorities muzzled doctors who were first to recognize the new infection, and they may not have been fully transparent about the number of infections and deaths even after the alarm was raised.
“As the investigation goes on, we often learn there are less severely infected people, and even people who are infected who don’t get sick at all.” It is also not clear whether cases and deaths in China are being carefully tracked and reported. Diagnostic kits and other health resources have been in short supply in the affected regions.
By comparison, roughly 200,000 people are hospitalized with the flu each year in the United States, and about 35,000 people die. Last week, the W.H.O. said that while the majority of patients with the new coronavirus have mild disease, 20 percent develop severe illness, including pneumonia, respiratory failure and sometimes death.
But while some scientists say the new virus appears to be less severe than other coronaviruses, like SARS and MERS, it is not clear how many people have been infected with the Wuhan coronavirus. Some epidemiological models put the figure as high as 100,000 in China. The W.H.O. estimated the death rate among those infected at 2 percent. That’s as high as the death rate of the pandemic Spanish flu in 1918.
“The information we know is changing rapidly,” said Dr. Julie Vaishampayan, chairwoman of the public health committee of the Infectious Diseases Society of America. “Whenever a new virus comes out, it takes a while to learn about it. There are going to be a lot of changes.” Scientists don’t know who is most susceptible to the new coronavirus. Does it pose a risk to young healthy people? Or, like seasonal flu, is it primarily a threat to the frail and elderly, and those with underlying health problems?
The Wuhan coronavirus is most likely transmitted mostly through coughing and sneezing, as is the case with influenza and other respiratory viruses, Dr. Vaishampayan said. “Whenever a new virus comes out, it takes a while to learn about it,” said Dr. Julie Vaishampayan, chairwoman of the public health committee of the Infectious Diseases Society of America. Right now, she said, “The information about coronavirus is changing rapidly.”
Scientists are scrambling to understand how easily the virus is transmitted. A close examination of one family, published on Friday in the medical journal The Lancet, suggested that the virus was passed from one ill relative to six others; only two had contact with the initial patient. At least 17,000 people are known to have been infected, and at least 360 have died. Most of the infected lived in Wuhan or had recently traveled there.
The Chinese Center for Disease Control and Prevention analyzed 198 confirmed cases in Wuhan. Researchers found that 22 percent had direct exposure to the meat market, and 32 percent had contact with people who had a fever or respiratory disease. Epidemics caused by other members of the coronavirus family, SARS and MERS, have had high death rates: 10 percent for SARS, and about 35 percent for MERS.
But roughly half had neither been to the market nor had contact with anyone who was sick. Sixteen health care workers were infected while caring for patients, the report said. Influenza kills more people every year, but its mortality rate is only about 0.1 percent. The number of deaths is high because so many people become infected.
Researchers at Imperial College London estimated that in the current outbreak, each infected person has passed the virus to 2.6 other people, on average. But statistical models produced so early in an outbreak often turn out to be wrong.
About 14,000 people are known to have been infected, and at least 132 have died. Most of those infected lived in Wuhan, a city of 11 million in central China, or had recently traveled there.
Epidemics caused by other members of the viral family, SARS and MERS, have had high death rates: 10 percent for SARS, and about 35 percent for MERS.
Influenza kills more people every year, but its mortality rate is only about 0.1 percent. The number of the deaths is high because so many people become infected. The death rate of the pandemic Spanish flu in 1918 was about 2 percent.
Widespread coronavirus epidemics have the potential to take a heavy toll, so the health authorities scramble to stamp them out.Widespread coronavirus epidemics have the potential to take a heavy toll, so the health authorities scramble to stamp them out.
Though it is too soon to know the death rate for the new virus, the World Health Organization reported on Tuesday that most patients have a mild illness, while an estimated 20 percent develop severe disease, including pneumonia and respiratory failure that may lead to death. A major concern is that with both SARS and MERS, a few patients inexplicably became “superspreaders” who infected huge numbers of people.
A major concern is that with both SARS and MERS, a few patients inexplicably became “superspreaders” who infected huge numbers of people. At a hospital in Seoul, South Korea, in 2015, one man with MERS transmitted it to 82 patients. Health care workers are particularly vulnerable. At a hospital in Seoul, South Korea, in 2015, one man with MERS transmitted it to 82 patients.
Most respiratory viruses are transmitted through coughing and sneezing, but troubling new evidence suggests people who are infected with the new virus may be spreading it before they even know that they have any symptoms.
Though Chinese authorities played down the likelihood of human-to-human transmission at first, it has now become clear there is significant and sustained transmission from person to person.
In Germany, a 35-year-old businessman was infected by a colleague visiting from Shanghai. She was healthy during her trip to Germany, and only fell ill during her flight home. Three other employees of the man’s company were also infected; two of them had had no contact with the visitor.
That’s “bad news,” said Dr. William Schaffner, an expert in infectious diseases at Vanderbilt University Medical Center.
When people don’t know they are infected, “they’re up and about, going to work or the gym or to religious services, and breathing on or near other people,” Dr. Schaffner said.
“Obviously sick people constrain themselves, and you have fewer opportunities for the virus to spread from one person to another.”
On Jan. 8, The New York Times reported that Chinese researchers had identified a new coronavirus as the pathogen behind a mysterious illness that had sickened 59 people in Wuhan.On Jan. 8, The New York Times reported that Chinese researchers had identified a new coronavirus as the pathogen behind a mysterious illness that had sickened 59 people in Wuhan.
The cases were linked to a market that sold live fish, animals and birds. The market was later shut down and disinfected.The cases were linked to a market that sold live fish, animals and birds. The market was later shut down and disinfected.
The main treatment is supportive care, including making sure the patient is getting enough oxygen, and using a ventilator to push air into the lungs if necessary, Dr. Vaishampayan said. Patients should rest and drink plenty of fluids “while the immune system does its job and heals itself,” she said. Past outbreaks of similar illnesses, including SARS, also are believed to have emerged from live animal markets. The coronavirus that causes MERS is transmitted to humans by camels.
No drugs have been approved for any coronavirus diseases, including the Wuhan coronavirus, though an antiviral medication called remdesivir appears to be effective in animals. Chinese officials are experimenting with at least one other H.I.V. drug to treat the infection. The animal that was the source of the new coronavirus is still not known, and the destruction of the Wuhan meat market has made the question nearly impossible to investigate.
Scientists were very quick to identify the virus, and officials with the National Institutes of Health said that advances in technology may make it possible to test a vaccine against the Wuhan coronavirus within three months. Bats are considered a possible source, because they have evolved to coexist with many viruses, including coronaviruses. But it’s very possible the virus was transmitted from bats to an intermediate animal, and then to humans.
Animals are the most likely primary source of the outbreak, but it is still not clear which animals. Past outbreaks of similar illnesses, including SARS, also are believed to have emerged from live animal markets. The coronavirus that causes MERS is transmitted to humans by camels. Symptoms of this virus include fever, severe cough and difficulty breathing or shortness of breath. The illness causes lung lesions and pneumonia. Milder cases may resemble the flu or a bad cold, making detection difficult.
But though the first patients sickened by the Wuhan coronavirus were thought to have contracted the disease at the market, the illness can also be transmitted from person to person. A growing number of people, including medical professionals caring for patients, have become infected. That makes the virus more difficult to contain. Patients may exhibit other symptoms too, such as gastrointestinal problems or diarrhea. The incubation period — the time from exposure to the onset of symptoms — is believed to be anywhere from a few days to two weeks.
The Chinese authorities have closed off transportation links from and within Wuhan and other affected cities, encircling roughly 50 million people. Bus service has been curtailed, as has travel abroad. The government is building two new hospitals to handle coronavirus patients; one is to be opened on Monday. If you have a fever or cough and recently visited China, or spent time with someone who did, see your health care provider. Call first, so they can prepare for your visit and take steps to protect other patients and staff from potential exposure.
Large public gatherings and performances were banned in Wuhan, and the government announced that all residents were required to wear masks in public to help prevent the disease from spreading. Movie theaters were closed throughout much of the country. There is a diagnostic test that can tell if you are infected. It was developed by the Centers for Disease Control and Prevention, based on genetic information about the virus provided by the Chinese authorities.
Governments around the world have been screening passengers who originated from Wuhan at ports of entry for signs of illness, and the United States is expanding its screening of passengers from China to 20 airports. About 200 American evacuees are held in quarantine on an air base in Southern California. Right now tests are done by the C.D.C. in Atlanta, but the agency plans to share the test with states and laboratories as soon as it is refined.
The Chinese government and the W.H.O. have agreed that international teams of scientists will be allowed into the country to help evaluate and contain the outbreak. The main treatment for coronavirus is supportive care, including making sure the patient is getting enough oxygen, and using a ventilator to push air into the lungs if necessary, Dr. Vaishampayan said. Patients should rest and drink plenty of fluids “while the immune system does its job and heals itself,” she said.
Symptoms include fever, severe cough and difficulty breathing or shortness of breath. The illness causes lung lesions and pneumonia. Milder cases may resemble the flu or a bad cold, making detection difficult. The incubation period — the time from exposure to the onset of symptoms — is believed to be about two weeks. No drugs have been approved for any coronavirus diseases, including the Wuhan coronavirus, though an antiviral medication called remdesivir appears to be effective in animals and was used to treat a patient in Washington State.
Chinese authorities said they have seen cases that did not meet the usual description. In these patients, the first symptoms were gastrointestinal, including diarrhea. Chinese officials are also experimenting with at least one other H.I.V. drug to treat the infection.
Ma Xiaowei, head of China’s national health commission, has asserted that infected people could spread the virus even if they did not have symptoms. The statement surprised and perplexed American experts, who want to see the scientific evidence so they can analyze it themselves. A coronavirus vaccine is still months away — and perhaps years. While new technology, advancements in genomics and improved global coordination have allowed researchers to move at unprecedented speed, vaccine development remains an expensive and risky process.
The State Department has warned against all nonessential travel to China. The C.D.C. urged all who must go to practice enhanced precautions — avoiding contact with anyone who is sick, as well as with animals and the markets in which they are sold. With each new outbreak, scientists typically have to start from scratch. After the SARS outbreak in 2003, it took researchers about 20 months to get a vaccine ready for human trials. (The vaccine was never needed, because the disease was eventually contained.)
Anyone who is older or has an underlying health condition should consult with a health provider before making a trip to China. By the time of the Zika outbreak in 2015, researchers had brought the vaccine development timeline down to six months.
Dr. Schaffner, of Vanderbilt University Medical Center, said travelers should practice “good hand hygiene” — washing hands frequently and avoiding touching their faces — and maintain a distance from anyone who is coughing and sneezing. Now, they hope that work from past outbreaks will help cut the timeline further. Scientists at the National Institutes of Health and several companies are working on vaccine candidates.
Travelers should monitor their health upon their return. If a cough or fever develops, call health providers before going in, so they can prepare and put protective measures in place. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said a preliminary clinical trial may get off the ground in as little as three months. But researchers would still need to conduct extensive testing to prove a vaccine is safe and effective.
If you have a respiratory infection, wearing a mask helps protect the people around you from illness by reducing the risk of spreading the infection, experts say. Wearing a surgical mask may somewhat protect you from infection in a crowd if there is an outbreak, but, generally, surgical masks are not closefitting enough to filter all the air you are breathing in. Even under the best circumstances, it could take at least a year — maybe longer — for a vaccine to be available.
Experts say you are better off washing your hands frequently throughout the day. If you have a respiratory infection, wearing a mask helps protect the people around you from illness by reducing the risk that you will spread the infection. And wearing a surgical mask may somewhat protect you from infection in a crowd if there is an outbreak.
At the moment, the risk of infection with the new coronavirus in the United States — where there are only eight confirmed cases so far — “is way too low to start wearing a face mask,” Dr. Rabinowitz said. “The risk is very, very low to the general public.” But, generally, surgical masks are not closefitting enough to filter all the air you are breathing in and N95 respirators are extremely uncomfortable.
American health officials are working closely with the W.H.O. and state and local health departments to monitor the situation. The C.D.C., which has activated an emergency response system, has expanded screening of passengers from China to 20 ports of entry, where workers are looking for signs of illness and providing information about the risk. The agency has developed a diagnostic test for the virus, technically called the 2019-nCoV virus. Experts recommend washing your hands frequently throughout the day. Avoid touching your face, and maintain a distance from anyone who is coughing or sneezing.
The C.D.C. has instructed hospitals around the country to ask patients who come in with fever or respiratory illness about recent travel to Wuhan or about contact with anyone who recently traveled to Wuhan. At the moment, the risk of infection with the new coronavirus in the United States — where there are 11 confirmed cases so far — “is way too low for the general public to start wearing a face mask,” Dr. Rabinowitz said.
C.D.C. teams are providing assistance with state investigations and helping to track down anyone who may have come in contact with the infected individuals. But, he added, “if you have symptoms of a respiratory illness, wearing a mask reduces the risk of infecting others.”
_______ Not if you can avoid it. The State Department has warned Americans not to go to China unless it is absolutely essential.
Karen Zraick contributed reporting. If travelers must go, the C.D.C. urges enhanced precautions: avoiding contact with anyone who is sick, as well as with animals and the markets in which they are sold; and refraining from eating raw or undercooked meats.
Anyone who is older or has an underlying health condition, which increases susceptibility to infections, should consult with a health provider before making a trip. Access to medical care in China may be difficult, given the outbreak, and federal officials warned that new travel restrictions could be imposed on return, including quarantine.
China has taken drastic actions to bar people from leaving affected areas, though 5 million people departed Wuhan alone before the restrictions went into effect.
Residents have been told to wear masks in public to prevent the spread of the disease. Two new hospitals for coronavirus patients are being erected; the first opened on Monday.
Governments around the world have been screening incoming passengers from China for signs of illness, and some have gone further, barring entry to people from China. Russia and Mongolia have closed most of their borders with China. Australia said it will evacuate citizens from Wuhan and quarantine them for 14 days on Christmas Island.
C.D.C. teams are also providing assistance with state health investigations of infections, including contact-tracing, which means making sure anyone who may have been in contact with an infected individual is warned of the exposure and their health is monitored.
The work will enhance the understanding of the virus and how to prevent its spread. C.D.C. teams have also offered to send public health experts to China to help with the investigation and containment efforts.
Reporting was contributed by Knvul Sheikh.