Coronaviruses are a large family of viruses, some causing illness in people and others that circulate among animals, including camels, cats and bats. Rarely, animal coronaviruses can evolve and infect people and then spread between people such as has been seen with MERS and SARS.
When person-to-person spread has occurred with MERS and SARS, it is thought to have happened via respiratory droplets produced when an infected person coughs or sneezes, similar to how influenza and other respiratory pathogens spread. Spread of MERS and SARS between people has generally occurred between close contacts. Past MERS and SARS outbreaks have been complex, requiring comprehensive public health responses.
Early on, many of the patients in the outbreak in Wuhan, China reportedly had some link to a large seafood and animal market, suggesting animal-to-person spread. However, a growing number of patients reportedly have not had exposure to animal markets, suggesting person-to-person spread is occurring. At this time, it’s unclear how easily or sustainably this virus is spreading between people.
Both MERS and SARS have been known to cause severe illness in people. The situation with regard to 2019-nCoV is still unclear. While severe illness, including illness resulting in a number of deaths has been reported in China, other patients have had milder illness and been discharged.
There are ongoing investigations to learn more. This is a rapidly evolving situation and information will be updated as it becomes available.
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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).
Investigations are ongoing to learn more, but person-to-person spread of 2019-nCoV is occurring. It’s important to note that person-to-person spread can happen on a continuum. Some viruses are highly contagious (like measles), while other viruses are less so. It’s not clear yet how easily 2019-nCoV spreads from person-to-person. It’s important to know this in order to better assess the risk posed by this virus. While CDC considers this is a very serious public health threat, based on current information, the immediate health risk from 2019-nCoV to the general American public is considered low at this time. Nevertheless, CDC is taking proactive preparedness precautions.
What to Expect
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 some person-to-person spread will continue to occur.
Meanwhile in China, the government is issuing continuing news and information on the spread and prevention on it's television outlet China Global Television Network with live English and other language broadcasts at https://america.cgtn.com/tv-schedule. The World Today news program airs weekdays at 2, 3, 5, 6:30 and 8PM and weekends at 2, 3, 4, 6 and 7PM and usually on the hour during the morning hours where Coronavirus updates are shown.
Additional Information https://www.cdc.gov/coronavirus/2019-nCoV/summary.html