Information about the novel coronavirus (the virus that causes COVID-19) is constantly evolving. We will refresh our novel coronavirus content periodically based on newly published peer-reviewed findings to which we have access. For the most reliable and up-to-date information, please visit the CDC website or the WHO’s advice for the public.
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Chances are, you’ve had a cold (or several) in your lifetime. You may have even experienced a more intense respiratory infection at some point, such as influenza (“the flu”) or pneumonia. If you have, you’ll know that respiratory infections can cause a whole host of symptoms, including fever, chest pain, congestion, cough, sneezing, shortness of breath, sore throat, body aches, fatigue, and more. But you’ll also know that you probably don’t experience all of these symptoms every time you get sick, and the symptoms can also range from mild to severe. For example, sometimes, the common cold is just an annoyance, but other times, infections can be so bad they keep you in bed (or may even require hospitalization and breathing assistance).
Part of the reason for this is that not all respiratory infections are the same. They can be caused by different organisms (such as different types of bacteria, viruses, or fungi), and they can infect different parts of your respiratory system (such as the inside of your nose or lungs).
But the other part of the reason for this is that not everybody experiences the same disease in the same way. Certain factors, such as your age or whether you have other medical conditions, can put you at a higher risk of developing serious disease. And this is especially important to keep in mind during the ongoing coronavirus disease 2019 (COVID-19) pandemic.
COVID-19 is caused by a virus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 is part of a family of viruses known as coronaviruses. Some coronaviruses cause respiratory illnesses in humans. These include the common cold, severe acute respiratory syndrome (SARS), and Middle East respiratory syndrome (MERS). Like these other diseases, COVID-19 is a respiratory illness.
If you have been keeping up with the news, you may have heard that most people with COVID-19 experience mild symptoms. In fact, an early Chinese study reported that 80.9% of individuals infected with the virus only experience mild disease (Novel Coronavirus Pneumonia Emergency Response Epidemiology Team, 2020). Additionally, at a press briefing on April 5, 2020, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Disease, estimated that 25–50% of people who are infected may be entirely asymptomatic, meaning they don’t experience any symptoms at all (and may not even know they have the virus) (U.S. Department of State, 2020).
But there is another end of the spectrum. A different Chinese study, which looked at over 44,000 people with confirmed COVID-19, found that 14% developed severe disease (defined as meeting certain breathing conditions), 5% developed critical disease (defined as having respiratory failure, organ failure, or shock), and 2.3% died (Wu, 2020). While the exact fatality rate of COVID-19 differs depending on a variety of factors, the point is: SARS-CoV-2 can cause such a range of disease that some are asymptomatic while others are dying.
What are the symptoms of COVID-19?
SARS-CoV-2 causes pneumonia in some patients. According to the Centers for Disease Control and Prevention (CDC), symptoms start showing up between 2–14 days after exposure (Centers for Disease Control and Prevention, 2020b). One study found that the average time before symptoms show up is 5.1 days, with 97.5% of infected people experiencing symptoms within 11.5 days (Lauer, 2020).
The most common symptoms of COVID-19 are (UpToDate, 2020):
- Muscle pain
- Shortness of breath
- Sore throat
Less common symptoms include (UpToDate, 2020):
- Loss of smell
- Loss of taste
- Abdominal pain
- Runny nose
Who is at greater risk for severe illness with COVID-19?
It is possible for everyone to develop severe symptoms. Just because you are young and healthy does not mean you are entirely protected from the disease. However, advanced age and certain medical comorbidities do put you at an increased risk.
Having any of the following underlying medical conditions is associated with developing severe disease from COVID-19 (CDC, 2020a):
- Chronic kidney disease
- Chronic obstructive pulmonary disease (COPD)
- Weakened immune system
- Heart disease
- Sickle cell disease
- Type 2 diabetes
The CDC also offers more information for a few specific groups:
- People with asthma: https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/asthma.html
- People with HIV: https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/hiv.html
- People with disabilities: https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/people-with-disabilities.html
- Pregnant and breastfeeding women: https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/pregnancy-breastfeeding.html
- People experiencing homelessness: https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/homelessness.html
What about age?
You have likely heard that older adults are at increased risk of having severe symptoms and dying from COVID-19, and this is true. Multiple studies have shown that older age is associated with poorer outcomes. One study found that 31% of cases, 45% of hospitalizations, 53% of intensive care unit (ICU) admissions, and 80% of deaths associated with COVID-19 were in individuals aged 65 and over. It also found that the highest percentage of severe outcomes was in individuals aged 85 and over (Bialek, 2020).
To reiterate, 8 out of 10 deaths in the United States from COVID-19 have been in individuals aged 65 and over. The CDC offers specific information for older adults, which can be found here: https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/older-adults.html
So, what should you do?
No matter who you are and what your medical conditions are, there are several easy steps you can take to help prevent getting infected with SARS-CoV-2. If possible, avoid contact with others—especially those who are sick. If you do have to leave your house, remember to practice social distancing, which involves avoiding large groups of people and staying at least six feet away from everybody else. If you are in a public area where social distancing is difficult, wear a cloth face covering (this protects others from you, in case you happen to be sick). Wash your hands frequently—especially before eating and touching your face. And if you do think you are sick and at risk of getting severe symptoms, do not hesitate to seek medical care.