ENGLISH – CDC : COVID-19 Situation Summary
This is an emerging, rapidly evolving situation and the CDC will provide updated information as it becomes available, in addition to updated guidance, on the CDC Summary Page.
Source and Spread of the Virus
Coronaviruses are a large family of viruses that are common in people and 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-CoV, SARS-CoV, and now with this new virus (named SARS-CoV-2). The SARS-CoV-2 virus is a betacoronavirus, like MERS-CoV and SARS-CoV. All three of these viruses have their origins in bats.
Early on, many of the patients at the epicenter of the outbreak in Wuhan, Hubei Province, 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. Person-to-person spread was subsequently reported outside Hubei and in countries outside China, including in the United States. Some parts of the United States now have ongoing community spread with the virus that causes COVID-19, which means some people have been infected and it is not known how or where they became exposed.
The complete clinical picture with regard to COVID-19 is not fully known. Reported illnesses have ranged from very mild (including some with no reported symptoms) to severe, including illness resulting in death. While information so far suggests that most COVID-19 illness is mild, a report out of China suggests serious illness occurs in 16% of cases. Older people and people of all ages with severe chronic medical conditions — like heart disease, lung disease and diabetes, for example — seem to be at higher risk of developing serious COVID-19 illness.
Risk depends on characteristics of the virus, including 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, vaccines or medications that can treat the illness) and the relative success of these. In the absence of vaccine or treatment medications, non-pharmaceutical interventions become the most important response strategy. These are community interventions that can reduce the impact of disease. The risk from COVID-19 to Americans can be broken down into risk of exposure versus risk of serious illness and death.
Risk of exposure:
The immediate risk of being exposed to this virus is still low for most Americans, but as the outbreak expands, that risk will increase. Cases of COVID-19 and instances of community spread are being reported in a growing number of states.
- People in places where ongoing community spread of the virus that causes COVID-19 has been reported are at elevated risk of exposure, with the level of risk dependent on the location.
- Healthcare workers caring for patients with COVID-19 are at elevated risk of exposure.
- Close contacts of persons with COVID-19 also are at elevated risk of exposure.
- Travelers returning from affected international locations where community spread is occurring also are at elevated risk of exposure, with level of risk dependent on where they traveled.
Risk of Severe Illness:
Early information out of China, where COVID-19 first started, shows that some people are at higher risk of getting very sick from this illness. This includes:
- Older adults, with risk increasing by age.
- People who have serious chronic medical conditions like:
- Heart disease
- Lung disease
What May Happen
More cases of COVID-19 are likely to be identified in the United States in the coming days, including more instances of community spread. The CDC expects that widespread transmission of COVID-19 in the United States will occur. In the coming months, most of the U.S. population will be exposed to this virus. Widespread transmission of COVID-19 could translate into large numbers of people needing medical care at the same time. Schools, child care centers, and workplaces, may experience more absenteeism. Hospitals and healthcare systems may become overloaded, with elevated rates of hospitalizations and deaths. Other critical infrastructure, such as law enforcement, emergency medical services, and sectors of the transportation industry may also be affected.
At this time, there is no vaccine to protect against COVID-19 and no medications approved to treat it. Non-pharmaceutical interventions will be the most important response strategy to try to delay the spread of the virus and reduce the impact of disease.