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COVID-19: A Glossary

Whether you’re reading the news, watching TV or scrolling through social media, a lot of information about COVID-19 is coming your way. The words used might be confusing and intimidating. Here are quick explanations of some commonly used COVID-19 terms.

Center for Disease Control (CDC): The United States' health protection agency with the mission to save lives and protect people from health threats.

Community spread: The spread of a disease for which the source of infection is unknown.

Confirmed case: A person who tested positive for COVID-19, confirmed by the CDC.

Congregate settings: Crowded public places where close contact with others may occur, such as malls, theaters and stadiums.

Coronavirus: A large family of viruses that includes respiratory illnesses. "Corona," meaning crown in Latin, refers to the shape of the virus under a microscope.

COVID-19: COVID-19 stands for "coronavirus disease 2019" and describes the illness caused by the coronavirus.

Epidemic: The occurrence of more cases of disease than expected in a given area or among a specific group of people of a particular period of time.

Flatten (Flattening) the curve: Refers to the potential success of social distancing measures to prevent surges in illness that could overwhelm health care systems.

Incubation period: The amount of time it takes for someone who is infected to start showing symptoms. For COVID-19, symptoms might not appear for 14 days after exposure.

Pandemic: A worldwide spread of a new disease

Person Under Investigation (PUI): Any person who is under investigation for having the virus that causes COVID-19. The person shows COVID-19-like symptoms, but is not confirmed to have the virus.

Presumptive positive case: A person for whom the initial test for the virus by a public health lab was positive, but not yet confirmed by the federal Centers for Disease Control and Prevention.

Quarantine: A restriction on people or groups who don’t have symptoms, but who are presumed to have been exposed to a contagious disease. Quarantine prevents contact with others so that they don’t unknowingly infect anyone.

Self-observation: Being observant of fever, cough or difficulty breathing. Based on CDC guidelines, if you think you may have COVID-19 and are experiencing minor symptoms, Memorial Hermann recommends you self-quarantine at home for at least 14 days and utilize virtual care options to consult with a healthcare provider. For severe symptoms, call ahead to your local Emergency Center prior to arriving or dial 911 if you need emergent care.

Social distancing: A public health practice that aims to prevent sick people from coming in close contact with healthy people in order to reduce opportunities for disease transmission. It can include large-scale measures like canceling group events or closing public spaces, as well as individual decisions such as avoiding crowds.

Symptomatic: When a person is showing symptoms of a particular illness or a disease. For COVID-19, that would include symptoms like cough, fever or shortness of breath.

World Health Organization (WHO): A specialized agency under the United Nations concerned with world public health. The WHO is responsible for the World Health Report, the World Health Survey, and World Health Day.