COVID-19 is a respiratory disease caused by a new virus discovered in late 2019. The WHO declared COVID-19 a global pandemic in March 2020. Being aware of symptoms and effective prevention strategies can help protect you and others from COVID-19.
What Is COVID-19?
COVID-19 spreads from one person to another through droplets or aerosols containing the SARS-CoV-2 coronavirus. Aerosols are extremely tiny droplets that are light enough to float through the air.
The most common way the disease spreads is during close contact with someone who has an infection, even if they do not have symptoms or know they are infected. Someone with a COVID-19 infection releases droplets and aerosols containing the virus when they cough, sneeze, talk, sing or simply exhale. Most of these droplets fall to the ground within six feet, but some aerosols may linger in the surrounding air and even travel on small air currents in a room.
If these droplets reach your nose, mouth or eyes or if you inhale the aerosols, they can cause an infection. Less often, you might become ill if they touch a surface where infected droplets fell and then touch your nose, mouth or eyes.
Scientists do not yet know how many droplets or aerosols are necessary to cause an infection. COVID-19 is more contagious than the flu but not as contagious as measles. People become contagious a few days before they first experience a fever or any other symptoms.
Symptoms of COVID-19
People can begin feeling symptoms of COVID-19 anywhere from two to 14 days after exposure to the virus. Most people start feeling symptoms about four to five days after exposure.
These are the most common symptoms of COVID-19:
- Fever or chills
- Shortness of breath or difficulty breathing
- Muscle aches or body aches
- Loss of sense of taste or smell
- Sore throat
- Nasal congestion or runny nose
- Nausea or vomiting
COVID-19 typically lasts one to three weeks in most people, but some people experience long-term effects for many weeks or even months. The most common long-term effects include fatigue, shortness of breath, cough, joint pain and chest pain.
Experts estimate that up to one in five people with a COVID-19 infection are asymptomatic and never develop symptoms. However, infected people can still transmit the disease even without symptoms.
Risk Factors for Serious Disease
People of any age can develop COVID-19 after exposure to the virus, and people of all ages have died from it. However, some groups are more likely than others to have severe disease, complications or death.
The risk of a serious COVID-19 infection increases with a person’s age, and older adults have the highest risk of being hospitalized or dying from the disease. According to the CDC, eight out of 10 people who have died from COVID-19 are 65 years old or older.
For example, people ages 50 to 64 are four times more likely to be hospitalized and 30 times more likely to die from COVID-19 than people ages 18 to 29. People ages 75 to 84 are 220 times more likely to die from COVID-19 than people ages 18 to 29.
People with certain preexisting conditions also have a higher risk of severe disease or death from COVID-19. These conditions include:
- Type 2 diabetes
- Down syndrome
- Sickle cell disease
- Chronic kidney disease
- Chronic obstructive pulmonary disease (COPD)
- A weakened immune system from an organ transplant
- Heart conditions, such as heart failure or coronary artery disease
- Developmental or behavioral disorders
- Substance use disorders
Reduce Your Risk of Catching COVID-19
There are several ways to reduce your risk of a COVID-19 infection. The most effective way is to keep physical distance from people outside your household. The CDC recommends staying home as much as possible and staying at least six feet away from others when around people.
Wear a cloth, surgical mask or similar face covering over your nose and mouth when out in public or around anyone who is not from your household. This helps protect you from aerosols and protects others if you have an infection.
Wash your hands frequently with soap and water or use a hand sanitizer containing at least 60% alcohol. Regularly disinfect any frequently touched surfaces.
Avoid gatherings of people from outside your household. Indoor family gatherings are one of the most common sources of new infections.
Avoid small or crowded indoor places, especially places with poor ventilation. Open windows, fans and high quality air filters can all help improve indoor ventilation.