Updated on July 11, 2024.
The SARS-CoV-2 virus causes coronavirus disease 2019, better known as COVID-19. It usually causes respiratory illness and can have symptoms similar to the flu, a cold, or pneumonia. COVID-19 may also affect many other areas of the body.
Regardless of the type of symptoms they experience, most people with COVID-19 only get mildly ill. Some, however, do get severe illness from the virus and while death from COVID is not as common as it was during the height of the pandemic, the disease can still prove fatal in certain cases. Other people who had a mild case can go on to develop symptoms for months or years after, known as “long COVID.”
Here’s what to know about how COVID-19 spreads, plus the latest recommendations from medical experts on how you can protect yourself, your loved ones, and members of your community.
How does COVID-19 spread?
COVID-19 spreads through particles that are emitted when infected people cough, sneeze, sing, breathe, or speak. Their breath carries tiny particles of the virus through the air that can be breathed in by others. This is known as aerosol transmission.
Larger, heavier contaminated respiratory droplets caused by sneezing or coughing can also fly through the air and land in a nearby person’s mouth, nose or eyes, or on nearby surfaces. If another person touches a contaminated surface, then touches their mouth, nose, or eyes, they can also become infected.
The virus can remain active on surfaces for hours or even days. That said, most people contract COVID-19 through the air rather than through contaminated surfaces.
Transmission of COVID-19 through aerosol particles is likely to occur indoors, particularly in areas with poor ventilation. Early in the pandemic, it was believed that airborne droplets were likeliest to travel within a range of 6 feet. Authorities therefore applied rules that asked people to stay at least 6 feet away from other people in public places.
In reality, the virus can travel through the air farther than 6 feet. It can also stay airborne in a room even after an infected person is no longer present, sometimes for several hours. The risk of getting infected goes down as more time passes from when the infected person leaves the room or as the infected person moves farther away.
Bottom line: COVID-19 is a highly contagious illness that spreads easily, probably more easily than the flu, according to the CDC.
How to avoid getting COVID-19
Fortunately, there are several tools you can use to protect yourself and others from illness.
Vaccination
The single best way to protect yourself against severe illness from COVID-19 is to get vaccinated. You may still contract the virus if you’re vaccinated, but you will be far less likely to become seriously ill, hospitalized, or die. Vaccination also helps reduce the risk of having “long COVID” symptoms.
Be sure to stay up-to-date with your vaccinations. The SARS-CoV-2 virus, like most viruses, changes and evolves over time into different variants that affect the human immune system in different ways. Staying current with the latest vaccination formulations will ensure you are protected against the latest variants of the virus.
The CDC recommends that everyone six months and older receive the latest COVID-19 vaccines (manufactured by Moderna, Novavax, or Pfizer-BioNTech). Depending on a person’s age and health profile, there are some special recommendations:
- Children between 6 months and 4 years old should get at least one dose of the updated vaccine and may need multiple doses to stay up-to-date
- Children 5 years and older should get a dose of an updated vaccine
- People with moderately or severely compromised (weakened) immune systems may need multiple doses of vaccine
- Anyone 65 years or older should get a second dose of an updated vaccine around four months after their first
Hygiene
To keep others safe from respiratory illnesses, it’s important to always practice good hygiene. This includes:
- Covering your mouth and nose when you sneeze, using a tissue or your elbow
- Washing your hands frequently with soap and water or applying hand sanitizer with 60 percent or more alcohol
- Cleaning high-touch surfaces like drawer handles and doorknobs
Masks
There are certain times when masks may be useful in preventing infection. These situations include when you or someone you interact with are sick or were recently sick or exposed to a virus, or if there is an outbreak of respiratory illness in the community. Wearing a mask or asking visitors to your home to wear a mask can be an effective protective measure against infection from COVID-19 during these times. Respiratory viruses have more difficulty spreading when masks are worn by infected people.
A mask can also protect the wearer if there are viral particles in the air around them. If you’re selecting a mask to wear, the best option is one that offers the highest level of protection while still being comfortable enough to wear. It should also fit snugly, covering both the mouth and nose completely.
Improve ventilation
COVID-19 and other respiratory viruses can spread easily through an unventilated indoor area. Improving the ventilation in your home or workplace is an effective way to lower your risk and the risk posed to your visitors.
Opening windows and doors to get fresh air and cross breezes can keep the air moving. Standalone fan units can be used to blow air from inside to outdoors. Exhaust fans from the stove and the bathroom can also help move air from indoors to outside.
If you’re able to, you can also use a portable high-efficiency particulate air (HEPA) purifier. Be sure to choose the correct size for your room.
Choose pleated filters for your central heating, ventilation, and air conditioning (HVAC) system, as they’re more effective. Set the fan on your air conditioning or heating to “on” rather than “auto” to make sure it’s running continuously.
The CDC recommends leaving these ventilation measures in place for about an hour after visitors have left, to maximize their protective effect.
Avoid crowds
To lower your risk of exposure to the virus, avoid going unmasked to crowded places or any indoor space with others that has poor ventilation.
Lack of symptoms doesn’t mean you're not contagious
People with mild or no symptoms are capable of spreading the virus unknowingly. These so-called “silent spreaders” can unwittingly pass the infection on to others—even when they feel fine. So, if you’re gathering together, particularly if there will be people who fall into at-risk categories for severe COVID-19 illness, consider asking attendees to take a test before a gathering in addition to taking the general protective steps described here.
(People at highest risk of severe COVID-19 include those over the age of 65, infants under 6 months, pregnant people, and people with certain health issues such as heart disease, obesity, chronic lung disease, cancer, diabetes, and chronic kidney disease.)
PCR tests are the most accurate kind of COVID test, but they have to be sent to a lab and can take several days to produce results. Antigen tests are quick and can be done at home, but they need to be done multiple times to get an accurate answer. If you have symptoms, you need to take two antigen tests, 48 hours apart. If you don’t have symptoms but suspect a COVID-19 infection, it’s important to take three antigen tests, each 48 hours apart.
There are many self-tests that you can purchase and most communities have testing locations that offer free or low-cost tests.
Other ways to protect yourself
It’s also important to do what you can to stay healthy and keep your immune system strong, such as getting quality sleep, eating a healthy diet, and exercising regularly. Getting a flu shot is also wise to protect against having multiple respiratory infections at the same time. In order to protect against the flu, everyone age 6 months and older should receive a seasonal flu shot.
How you can prepare
Having a plan in place for how you will respond in case you, loved ones, or community members get COVID-19 is a good idea. Be sure to consider anyone in your home or area who is at greater risk for severe infection and complications, including older people and those with underlying chronic health issues.
Other steps you can take:
- Make a list of local resources that can help you access information, support, medical attention or other essentials. It’s also a good idea to keep an emergency contact list, which includes family, friends, neighbors, healthcare providers (HCPs), employers and other essential phone numbers.
- Stock essential over-the-counter medications for congestion, cough, fever, and other respiratory symptoms.
- Create a "protected space" in your home that can be used to keep household members who are sick isolated from others who are not.
What to do if you might be sick
If you believe you may be infected with COVID-19 or might have been exposed to the coronavirus, you should take steps to isolate yourself and avoid spreading the illness to others.
If you develop signs of infection, call your HCP for advice. They may recommend testing for the virus and perhaps also for flu. Depending on your health background, they may advise you to recover at home, or they could recommend you receive antiviral treatment, which may help speed up recovery time and lessen the intensity of symptoms.
