Coronavirus Disease 2019 Basics

A novel coronavirus is a new coronavirus that has not been previously identified. The virus causing coronavirus disease 2019 (COVID-19), is not the same as the coronaviruses that commonly circulate among humans and cause mild illness, like the common cold.

A diagnosis with coronavirus 229E, NL63, OC43, or HKU1 is not the same as a COVID-19 diagnosis. Patients with COVID-19 will be evaluated and cared for differently than patients with a common coronavirus diagnosis.

On February 11, 2020 the World Health Organization announced an official name for the disease that is causing the 2019 novel coronavirus outbreak, first identified in Wuhan, China. The name of this disease is coronavirus disease 2019, abbreviated as COVID-19. In COVID-19, ‘CO’ stands for ‘corona,’ ‘VI’ for ‘virus,’ and ‘D’ for disease. Formerly, this disease was referred to as “2019 novel coronavirus” or “2019-nCoV”.

There are many types of human coronaviruses including some that commonly cause mild upper-respiratory tract illnesses. COVID-19 is a new disease, caused by a novel (or new) coronavirus that has not previously been seen in humans. The name of this disease was selected following the World Health Organization (WHO) best practicesexternal icon for naming new human infectious diseases.

People in the U.S. may be worried or anxious about friends and relatives who are living in or visiting areas where COVID-19 is spreading. Some people are worried about getting the disease from these people. Fear and anxiety can lead to social stigma, for example, toward people who live in certain parts of the world, people who have traveled internationally, people who were in quarantine, or healthcare professionals.

Stigma is discrimination against an identifiable group of people, a place, or a nation. Stigma is associated with a lack of knowledge about how COVID-19 spreads, a need to blame someone, fears about disease and death, and gossip that spreads rumors and myths.

Stigma hurts everyone by creating more fear or anger toward ordinary people instead of focusing on the disease that is causing the problem.

People can fight stigma by providing social support in situations where you notice this is occurring. Stigma affects the emotional or mental health of stigmatized groups and the communities they live in. Stopping stigma is important to making communities and community members resilient. See resources on mental health and coping during COVID-19. Everyone can help stop stigma related to COVID-19 by knowing the facts and sharing them with others in your community.

CDC’s overall case numbers are validated through a confirmation process with jurisdictions. The process used for finding and confirming cases displayed by different places may differ.

CDC’s COVID-19 case numbers include many publicly reported numbers, including information from state, local, territorial, international and external partners.

Delays in reporting can cause the number of COVID-19 cases reported on previous days to increase. (Sometimes this effect is described as “backfill.”) State, local, and territorial health departments report the number of cases that have been confirmed and share these data with CDC. Since it takes time to conduct laboratory testing, cases from a previous day may be added to the daily counts a few days late.

 

How COVID-19 Spreads

COVID-19 is caused by a coronavirus called SARS-CoV-2. Coronaviruses are a large family of viruses that are common in people and may different species of animals, including camels, cattle, cats, and bats.  Rarely, animal coronaviruses can infect people and then spread between people. This occurred with MERS-CoV and SARS-CoV, and now with the virus that causes COVID-19. More information about the source and spread of COVID-19 is available on the Situation Summary: Source and Spread of the Virus.

The virus that causes COVID-19 is thought to spread mainly from person to person, mainly through respiratory droplets produced when an infected person coughs or sneezes. These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs. Spread is more likely when people are in close contact with one another (within about 6 feet).

COVID-19 seems to be spreading easily and sustainably in the community (“community spread”) in many affected geographic areas. Community spread means people have been infected with the virus in an area, including some who are not sure how or where they became infected.

Learn what is known about the spread of newly emerged coronaviruses.

The number of cases of COVID-19 being reported in the United States is rising due to increased laboratory testing and reporting across the country. The growing number of cases in part reflects the rapid spread of COVID-19 as many U.S. states and territories experience community spread. More detailed and accurate data will allow us to better understand and track the size and scope of the outbreak and strengthen prevention and response efforts.

The virus that causes COVID-19 is spreading from person-to-person. People are thought to be most contagious when they are symptomatic (the sickest). That is why CDC recommends that these patients be isolated either in the hospital or at home (depending on how sick they are) until they are better and no longer pose a risk of infecting others. More recently the virus has also been detected in asymptomatic persons.

How long someone is actively sick can vary so the decision on when to release someone from isolation is made using a test-based or non-test-based strategy (i.e. time since illness started and time since recovery) in consultation with state and local public health officials. The decision involves considering the specifics of each situation, including disease severity, illness signs and symptoms, and the results of laboratory testing for that patient.

Learn more about CDC’s guidance on when to release someone from isolation and discharge hospitalized patients with COVID-19. For information on when someone who has been sick with COVID-19 is able to stop home isolation see Interim Guidance for Discontinuation of In-Home Isolation for Patients with COVID-19.

Someone who has been released from isolation is not considered to pose a risk of infection to others.

Quarantine means separating a person or group of people who have been exposed to a contagious disease but have not developed illness (symptoms) from others who have not been exposed, in order to prevent the possible spread of that disease. Quarantine is usually established for the incubation period of the communicable disease, which is the span of time during which people have developed illness after exposure. For COVID-19, the period of quarantine is 14 days from the last date of exposure because the incubation period for this virus is 2 to 14 days. Someone who has been released from COVID-19 quarantine is not considered a risk for spreading the virus to others because they have not developed illness during the incubation period.

Coronaviruses are generally thought to be spread from person to person through respiratory droplets. Currently, there is no evidence to support transmission of COVID-19 associated with food. Before preparing or eating food it is important to always wash your hands with soap and water for at least 20 seconds for general food safety. Throughout the day use a tissue to cover your coughing or sneezing, and wash your hands after blowing your nose, coughing or sneezing, or going to the bathroom.

It may be possible that a person can get COVID-19 by touching a surface or object, like a packaging container, that has the virus on it and then touching their own mouth, nose, or possibly their eyes, but this is not thought to be the main way the virus spreads.

In general, because of poor survivability of these coronaviruses on surfaces, there is likely very low risk of spread from food products or packaging.

Learn what is known about the spread of COVID-19.

Based on information about this novel coronavirus thus far, it seems unlikely that COVID-19 can be transmitted through food – additional investigation is needed.

It is not yet known whether weather and temperature affect the spread of COVID-19. Some other viruses, like those that cause the common cold and flu, spread more during cold weather months but that does not mean it is impossible to become sick with these viruses during other months.  There is much more to learn about the transmissibility, severity, and other features associated with COVID-19 and investigations are ongoing.

Community spread means people have been infected with the virus in an area, including some who are not sure how or where they became infected.

Generally coronaviruses survive for shorter periods at higher temperatures and higher humidity than in cooler or dryer environments. However, we don’t have direct data for this virus, nor do we have direct data for a temperature-based cutoff for inactivation at this point. The necessary temperature would also be based on the materials of the surface, the environment, etc. Regardless of temperature please follow CDC’s guidance for cleaning and disinfection.

At this time, CDC has no data to suggest that this new coronavirus or other similar coronaviruses are spread by mosquitoes or ticks. The main way that COVID-19 spreads is from person to person. See How Coronavirus Spreads for more information.

 

How to Protect Yourself

This is a rapidly evolving situation and the risk assessment may change daily. The latest updates are available on CDC’s Coronavirus Disease 2019 (COVID-19) website.

COVID-19 case counts for the United States are updated regularly online. See the current U.S. case count of COVID-19.

Visit the COVID-19 Prevention and Treatment page to learn about how to protect yourself from respiratory illnesses, like COVID-19.

There is information for people who have had close contact with a person confirmed to have, or being evaluated for, COVID-19 available online.

In light of new data about how COVID-19 spreads, along with evidence of widespread COVID-19 illness in communities across the country, CDC recommends that people wear a cloth face covering to cover their nose and mouth in the community setting. This is an additional public health measure people should take to reduce the spread of COVID-19 in addition to (not instead of) social distancing, frequent hand cleaning and other everyday preventive actions. A cloth face covering is not intended to protect the wearer, but may prevent the spread of virus from the wearer to others. This would be especially important in the event that someone is infected but does not have symptoms. A cloth face covering should be worn whenever people must go into public settings (grocery stores, for example). Medical masks and N-95 respirators are reserved for healthcare workers and other first responders, as recommended by current CDC guidance.

There is still a lot that is unknown about COVID-19 and how it spreads. This coronaviruses is thought to be spread most often by respiratory droplets. Although the virus can survive for a short period on some surfaces, it is unlikely to be spread from products or packaging that are shipped over a period of days or weeks at ambient temperatures. Currently there is no evidence to support transmission of COVID-19 associated with imported goods and there have not been any cases of COVID-19 in the United States associated with imported goods. Information will be provided on the Coronavirus Disease 2019 (COVID-19) website as it becomes available.

In healthcare settings across the United States, donated blood is a lifesaving, essential part of caring for patients. The need for donated blood is constant, and blood centers are open and in urgent need of donations. CDC encourages people who are well to continue to donate blood if they are able, even if they are practicing social distancing because of COVID-19. CDC is supporting blood centers by providing recommendations that will keep donors and staff safe. Examples of these recommendations include spacing donor chairs 6 feet apart, thoroughly adhering to environmental cleaning practices, and encouraging donors to make donation appointments ahead of time.

 

COVID-19 and Children

Based on available evidence, children do not appear to be at higher risk for COVID-19 than adults. While some children and infants have been sick with COVID-19, adults make up most of the known cases to date. You can learn more about who is at higher risk for severe illness from COVID-19 at People who are at higher risk for severe illness.

You can encourage your child to help stop the spread of COVID-19 by teaching them to do the same things everyone should do to stay healthy.

  • Avoid close contact with people who are sick.
  • Stay home when you are sick, except to get medical care.
  • Cover your coughs and sneezes with a tissue and throw the tissue in the trash.
  • Wash your hands often with soap and water for at least 20 seconds, especially after blowing your nose, coughing, or sneezing; going to the bathroom; and before eating or preparing food.
  • If soap and water are not readily available, use an alcohol-based hand sanitizer with at least 60% alcohol. Always wash hands with soap and water if hands are visibly dirty.
  • Clean and disinfect frequently touched surfaces and objects (e.g., tables, countertops, light switches, doorknobs, and cabinet handles).
  • Launder items, including washable plush toys, as appropriate and in accordance with the manufacturer’s instructions. If possible, launder items using the warmest appropriate water setting for the items and dry items completely. Dirty laundry from an ill person can be washed with other people’s items.

You can find additional information on preventing COVID-19 at Prevention for 2019 Novel Coronavirus and at Preventing COVID-19 Spread in Communities. Additional information on how COVID-19 is spread is available at How COVID-19 Spreads.

More information on Children and Coronavirus Disease 2019 (COVID-19) is available online.

No. The symptoms of COVID-19 are similar in children and adults. However, children with confirmed COVID-19 have generally presented with mild symptoms. Reported symptoms in children include cold-like symptoms, such as fever, runny nose, and cough. Vomiting and diarrhea have also been reported. It’s not known yet whether some children may be at higher risk for severe illness, for example, children with underlying medical conditions and special healthcare needs. There is much more to be learned about how the disease impacts children.

CDC recommends that people wear a cloth face covering their nose and mouth in the community setting during the COVID-19 pandemic, however, children younger than 2 years of age are listed as an exception. Children younger than 2 years should not wear a cloth face covering because of concerns that they might suffocate.

Outbreaks can be stressful for adults and children. Talk with your children about the outbreak, try to stay calm, and reassure them that they are safe. If appropriate, explain to them that most illness from COVID-19 seems to be mild. Children respond differently to stressful situations than adults. CDC offers resources to help talk with children about COVID-19.

This is a new virus and we are still learning about it, but so far, there does not seem to be a lot of illness in children. Most illness, including serious illness, is happening in adults of working age and older adults. However, children do get the virus and become ill. Many schools across the country have announced dismissals for temporary periods. Keep track of school dismissals in your community. Read or watch local media sources that report school dismissals. If schools are dismissed temporarily, use alternative childcare arrangements, if needed.

If your child/children become sick with COVID-19, notify their childcare facility or school. Talk with teachers about classroom assignments and activities they can do from home to keep up with their schoolwork.

Discourage children and teens from gathering in other public places while school is dismissed to help slow the spread of COVID-19 in the community.

 

School Dismissals and Children

  • The key to slowing the spread of COVID-19 is to practice social distancing. While school is out, children should not have in-person playdates with children from other households. If children are playing outside their own homes, it is essential that they remain 6 feet from anyone who is not in their own household.
  • To help children maintain social connections while social distancing, help your children have supervised phone calls or video chats with their friends.
  • Make sure children practice everyday preventive behaviors, such as washing their hands often with soap and water. Remember, if children meet outside of school in groups, it can put everyone at risk.
    • Revise spring break plans if they included non-essential travel.
  • Information about COVID-19 in children is somewhat limited, but current data suggest children with COVID-19 may have only mild symptoms. However, they can still pass this virus onto others who may be at higher risk, including older adults and people who have serious underlying medical conditions.
  • Stay in touch with your child’s school.
    • Many schools are offering lessons online (virtual learning). Review assignments from the school, and help your child establish a reasonable pace for completing the work. You may need to assist your child with turning on devices, reading instructions, and typing answers.
    • Communicate challenges to your school. If you face technology or connectivity issues, or if your child is having a hard time completing assignments, let the school know.
  • Create a schedule and routine for learning at home, but remain flexible.
    • Have consistent bedtimes, and get up at the same time, Monday through Friday.
    • Structure the day for learning, free time, healthy meals and snacks, and physical activity.
    • Allow flexibility in the schedule—it’s okay to adapt based on your day.
  • Consider the needs and adjustment required for your child’s age group.
    • The transition to being at home will be different for preschoolers, K-5, middle school students, and high school students. Talk to your child about expectations and how they are adjusting to being at home versus at school.
    • Consider ways your child can stay connected with their friends without spending time in person.
  • Look for ways to make learning fun.
    • Have hands-on activities, like puzzles, painting, drawing, and making things.
    • Independent play can also be used in place of structured learning. Encourage children to build a fort from sheets or practice counting by stacking blocks.
    • Practice handwriting and grammar by writing letters to family members. This is a great way to connect and limit face-to-face contact.
    • Start a journal with your child to document this time and discuss the shared experience.
    • Use audiobooks or see if your local library is hosting virtual or live-streamed reading events.
  • Check with your school on plans to continue meal services during the school dismissal. Many schools are keeping school facilities open to allow families to pick up meals or are providing grab-and-go meals at a central location.
  • Watch your child for any signs of illness.
    • If you see any sign of illness consistent with symptoms of COVID-19, particularly fever, cough, or shortness of breath, call your healthcare provider and keep your child at home and away from others as much as possible. Follow CDC’s guidance on “What to do if you are sick.”
  • Watch for signs of stress in your child.
  • Teach and reinforce everyday preventive actions.
    • Parents and caretakers play an important role in teaching children to wash their hands. Explain that hand washing can keep them healthy and stop the virus from spreading to others.
    • Be a good role model—if you wash your hands often, they’re more likely to do the same.
    • Make handwashing a family activity.
  • Help your child stay active.
    • Encourage your child to play outdoors—it’s great for physical and mental health. Take a walk with your child or go on a bike ride.
    • Use indoor activity breaks (stretch breaks, dance breaks) throughout the day to help your child stay healthy and focused.
  • Help your child stay socially connected.
  • Older adults and people who have serious underlying medical conditions are at highest risk of getting sick from COVID-19.
    • If others in your home are at particularly high risk for severe illness from COVID-19, consider extra precautions to separate your child from those people.
    • If you are unable to stay home with your child during school dismissals, carefully consider who might be best positioned to provide childcare. If someone at higher risk for COVID-19 will be providing care (older adult, such as a grandparent or someone with a serious underlying medical condition), limit your children’s contact with other people.
    • Consider postponing visits or trip to see older family members and grandparents. Connect virtually or by writing letters and sending via mail.
 

Preparing Your Home and Family for COVID-19

Create a household plan of action to help protect your health and the health of those you care about in the event of an outbreak of COVID-19 in your community:

  • Talk with the people who need to be included in your plan, and discuss what to do if a COVID-19 outbreak occurs in your community.
  • Plan ways to care for those who might be at greater risk for serious complications, particularly older adults and those with severe chronic medical conditions like heart, lung or kidney disease.
    • Make sure they have access to several weeks of medications and supplies in case you need to stay home for prolonged periods of time.
  • Get to know your neighbors and find out if your neighborhood has a website or social media page to stay connected.
  • Create a list of local organizations that you and your household can contact in the event you need access to information, healthcare services, support, and resources.
  • Create an emergency contact list of family, friends, neighbors, carpool drivers, health care providers, teachers, employers, the local public health department, and other community resources.

Practice everyday preventive actions to help reduce your risk of getting sick and remind everyone in your home to do the same. These actions are especially important for older adults and people who have severe chronic medical conditions:

  • Avoid close contact with people who are sick.
  • Stay home when you are sick, except to get medical care.
  • Cover your coughs and sneezes with a tissue and throw the tissue in the trash.
  • Wash your hands often with soap and water for at least 20 seconds, especially after blowing your nose, coughing, or sneezing; going to the bathroom; and before eating or preparing food.
  • If soap and water are not readily available, use an alcohol-based hand sanitizer with at least 60% alcohol. Always wash hands with soap and water if hands are visibly dirty.
  • Clean and disinfect frequently touched surfaces and objects (e.g., tables, countertops, light switches, doorknobs, and cabinet handles).
  • Launder items, including washable plush toys, as appropriate and in accordance with the manufacturer’s instructions. If possible, launder items using the warmest appropriate water setting for the items and dry items completely. Dirty laundry from an ill person can be washed with other people’s items.

Most people who get COVID-19 will be able to recover at home. CDC has directions for people who are recovering at home and their caregivers, including:

  • Stay home when you are sick, except to get medical care.
When to Seek Medical Attention

If you develop emergency warning signs for COVID-19 get medical attention immediately. Emergency warning signs include*:

  • Trouble breathing
  • Persistent pain or pressure in the chest
  • New confusion or inability to arouse
  • Bluish lips or face

*This list is not all inclusive. Please consult your medical provider for any other symptoms that are severe or concerning.

  • Use a separate room and bathroom for sick household members (if possible).
  • Wash your hands often with soap and water for at least 20 seconds, especially after blowing your nose, coughing, or sneezing; going to the bathroom; and before eating or preparing food.
  • If soap and water are not readily available, use an alcohol-based hand sanitizer with at least 60% alcohol. Always wash hands with soap and water if hands are visibly dirty.
  • Provide your sick household member with clean disposable facemasks to wear at home, if available, to help prevent spreading COVID-19 to others.
  • Clean the sick room and bathroom, as needed, to avoid unnecessary contact with the sick person.
  • Avoid sharing personal items like utensils, food, and drinks.

Talk to the school or facility about their emergency operations plan. Understand the plan for continuing education and social services (such as student meal programs) during school dismissals. If your child attends a college or university, encourage them to learn about the school’s plan for a COVID-19 outbreak.

Plan for potential changes at your workplace. Talk to your employer about their emergency operations plan, including sick-leave policies and telework options. Learn how businesses and employers can plan for and respond to COVID-19.

Handwashing is one of the best ways to protect yourself and your family from getting sick. Wash your hands often with soap and water for at least 20 seconds, especially after blowing your nose, coughing, or sneezing; going to the bathroom; and before eating or preparing food. If soap and water are not readily available, use an alcohol-based hand sanitizer with at least 60% alcohol.

Clean and disinfect frequently touched surfaces such as tables, doorknobs, light switches, countertops, handles, desks, phones, keyboards, toilets, faucets, and sinks.  If surfaces are dirty, clean them using detergent or soap and water prior to disinfection. To disinfect, most common EPA-registered household disinfectants will work. See CDC’s recommendations for household cleaning and disinfection.

CDC recommends handwashing with soap and water for at least 20 seconds or, using alcohol-based hand sanitizer with at least 60% alcohol when soap and water are not available. These actions are part of everyday preventive actions individuals can take to slow the spread of respiratory diseases like COVID-19.

  • When washing hands, you can use plain soap or antibacterial soap. Plain soap is as effective as antibacterial soap at removing germs.
  • If soap and water are not readily available, you can use an FDA-approved alcohol-based hand sanitizer that contains at least 60% alcohol. You can tell if the sanitizer contains at least 60% alcohol by looking at the product label.

CDC does not encourage the production and use of homemade hand sanitizer products because of concerns over the correct use of the ingredientsexternal icon and the need to work under sterile conditions to make the product. Local industries that are looking into producing hand sanitizer to fill in for commercial shortages can refer to the World Health Organization guidancepdf iconexternal icon. Organizations should revert to the use of commercially produced, FDA-approved product once such supplies again become available.

  • To be effective against killing some types of germs, hand sanitizers need to have a strength of at least 60% alcohol and be used when hands are not visibly dirty or greasy.
  • Do not rely on “Do It Yourself” or “DIY” recipes based solely on essential oils or formulated without correct compounding practices.
  • Do not use hand sanitizer to disinfect frequently touched surfaces and objects. See CDC’s information for cleaning and sanitizing your home.

See FAQs about hand hygiene for healthcare personnel responding to COVID-2019.

 

In Case of an Outbreak in Your Community

During an outbreak, stay calm and put your preparedness plan to work. Follow the steps below:

Protect yourself and others.

  • Stay home if you are sick. Keep away from people who are sick. Limit close contact with others as much as possi