On 31 December 2019, WHO (Workd Health Org.)was alerted to several cases of pneumonia in Wuhan City, Hubei Province of China. The virus did not match any other known virus. This raised concern because when a virus is new, we do not know how it affects people.
One week later, on 7 January, Chinese authorities confirmed that they had identified a new virus. The new virus is a coronavirus, which is a family of viruses that include the common cold, and viruses such as SARS and MERS. This new virus was temporarily named “2019-nCoV.”
WHO has been working with Chinese authorities and global experts from the day we were informed, to learn more about the virus, how it affects the people who are sick with it, how they can be treated, and what countries can do to respond.
Because this is a coronavirus, which usually causes respiratory illness, WHO has advice to people on how to protect themselves and those around them from getting the disease.
The CDC (Center for Disease Control) is also closely monitoring the outbreak of respiratory illness caused by a novel (new) coronavirus (named “2019-nCoV”) that was first detected in Wuhan City, Hubei Province, China and which continues to expand. Chinese health officials have reported thousands of infections with 2019-nCoV in China, with the virus reportedly spreading from person-to-person in many parts of that country. Infections with 2019-nCoV, most of them associated with travel from Wuhan, also are being reported in a growing number of international locations, including the United States.
Coronaviruses are a large family of viruses that are common in many different species of animals, including camels, cattle, cats, and bats. Rarely, animal coronaviruses can infect people and then spread between people such as with MERS and SARS.
Chinese health authorities were the first to post the full genome of the 2019-nCoV in GenBank, the NIH genetic sequence database, and in the Global Initiative on Sharing All Influenza Data (GISAID) portal, an action which has facilitated detection of this virus. CDC posted the full genome of the 2019-nCoV virus detected in the first and second U.S. patients to GenBank.
2019-nCoV is a betacoronavirus, like MERS and SARs, all of which have their origins in bats. The sequences from U.S. patients are similar to the one that China initially posted, suggesting a likely single, recent emergence of this virus from an animal reservoir.
Early on, many of the patients in the outbreak of respiratory illness caused by 2019-nCov in Wuhan, China had some link to a large seafood and live animal market, suggesting animal-to-person spread. Later, a growing number of patients reportedly did not have exposure to animal markets, indicating person-to-person spread. Chinese officials report that sustained person-to-person spread in the community is occurring in China. Learn what is known about the spread of newly emerged coronaviruses.
Imported cases of 2019-nCoV infection in people have been detected in the U.S. No person-to-person spread has been detected with this virus at the time, and this virus is NOT currently spreading in the community in the United States.
Both MERS and SARS have been known to cause severe illness in people. The complete clinical picture with regard to 2019-nCoV is still not fully clear. Reported illnesses have ranged from infected people with little to no symptoms to people being severely ill and dying. Learn more about the symptoms associated with 2019-nCoV.
There are ongoing investigations to learn more. This is a rapidly evolving situation and information will be updated as it becomes available.
Outbreaks of novel virus infections among people are always of public health concern. The risk from these outbreaks depends on characteristics of the virus, including whether and how well it spreads between people, the severity of resulting illness, and the medical or other measures available to control the impact of the virus (for example, vaccine or treatment medications).
This is a serious public health threat. The fact that this virus has caused severe illness and sustained person-to-person spread in China is concerning, but it’s unclear how the situation in the United States will unfold at this time.
The risk to individuals is dependent on exposure. At this time, some people will have an increased risk of infection, for example healthcare workers caring for 2019-nCoV patients and other close contacts. For the general American public, who are unlikely to be exposed to this virus, the immediate health risk from 2019-nCoV is considered low.
More cases are likely to be identified in the coming days, including more cases in the United States. Given what has occurred previously with MERS and SARS, it’s likely that person-to-person spread will occur, including in the United States.
While the immediate risk of this new virus to the American public is believed to be low at this time, everyone can do their part to help us respond to this emerging public health threat:
The following resources are available with information on 2019-nCoV