COVID-19, the disease caused by the new coronavirus, is unpredictable. Many people have no symptoms—though they can still be spreading the virus. Others experience life-threatening complications. But the majority of people with symptoms—about 80%—have only mild to moderate disease.
But it’s not always easy to know what version of the disease you have, how it will progress—and what your next steps should be.
Understanding the difference between mild, moderate, and severe symptoms, and when it’s moving from one stage to the next, can help you decide when to stay home or go to the hospital.
If you are feeling sick, you and your doctor will be able to determine what care you need based on your symptoms. In a relatively short period of time, doctors have learned a lot about COVID-19, including better ways to manage the disease, whether at home or at the hospital.
First, here is a list of symptoms.
Fever, cough, and tiredness are the most common. For some, the loss of taste or smell (or both) is one of the earliest signs that they may have caught the virus.
- Fever or chills
- Loss of taste or smell
- Difficulty breathing
- Muscle or body aches
- Sore throat
- Congestion or runny nose
- Nausea or vomiting
So how do you know how bad your symptoms are and when you need to seek medical help? There are actually five different categories of severity for COVID-19.
Asymptomatic or presymptomatic infection
This is when you have COVID-19 but don’t feel any symptoms at all. It could be that you will never experience symptoms—these are asymptomatic cases. Or you may be in the period between being infected but not yet having symptoms. In both situations, you are contagious and can spread the virus to others.
It’s estimated that many people infected with COVID-19 are asymptomatic. If you have tested positive but are not having symptoms, you still need to isolate yourself following the Centers for Disease Control and Prevention’s (CDC) guidelines. The CDC recommends that if you have COVID-19 but have no symptoms, you wait 10 days since the date you had your positive test before you can be around others. You can still make others sick even if you never have any symptoms.
Most COVID-19 cases are mild.
If you have a mild case, you will probably feel a little under the weather with some combination of COVID-19 symptoms. You might have a low fever, some coughing, maybe a headache or nausea, and perhaps you lose your taste and smell.
Most important is that you don’t have difficulty getting enough air (called dyspnea) or other problems with breathing. That would signal more serious illness.
If you test positive, call your doctor. You can probably treat yourself at home, but check with your doctor through telemedicine or telephone visits to make sure you’re not getting worse. Sometimes mild symptoms can become moderate.
People who are at high-risk of complications, such as people ages 65 and older, or who have underlying health conditions, like diabetes or heart disease, should talk to their doctors about whether they need to go to the hospital.
The main difference between mild and moderate COVID-19 is whether or not you have pneumonia. This is when the lungs have too much fluid in them and become inflamed, making it hard to breathe and causing shortness of breath. Your doctor may suggest you get an X-ray to check to see if you have pneumonia.
While you may not need to go to the hospital, keep in close contact with your doctor to monitor your illness. If your symptoms start getting worse, call your doctor. If you are struggling to breathe, go to the ER.
Some people with COVID-19 become severely ill. Your doctor will want you to go to the hospital.
According to the CDC, you should go to the ER if you have any of the following severe symptoms:
- Difficulty getting enough air
- Persistent pain or pressure in your chest
- New confusion
- Inability to wake up or stay awake
- Bluish lips or face
Some people, however, may have dangerously low oxygen levels without realizing it. Your doctor may ask you to monitor your oxygen saturation levels (how much oxygen is circulating in your blood) with a pulse oximeter. (They are sold at drugstores and online.)
Oxygen saturation that is consistently below 92% or adults needing to take more than 30 breaths per minute are red flags that the illness is worsening. Low oxygen can damage your organs. Your doctor will tell you to go to the ER.
At the hospital, you’ll be given supplemental oxygen and other vital signs will be checked. You’ll be given other treatments depending on how sick you are.
A small percentage of people with COVID-19 symptoms end up with the most extreme form. People with critical illness related to COVID-19 are best cared for in the hospital intensive care unit. The signs of critical illness include:
- Cytokine storm. Your immune system starts attacking your body. It sets off a chain reaction that can damage your liver, kidneys, lungs, and blood vessels as well as increase blood clots.
- These blood clots can not only cause additional harm to the lungs, but also can cause strokes if they form in the blood vessels of the brain, or kidney failure if they clog kidney blood vessels.
- Severe difficulty breathing. This is caused by acute respiratory distress syndrome (a more advanced form of pneumonia).
- Septic shock. The infection is spreading through the bloodstream, causing organs like the heart or kidneys to shut down.
- Cardiac dysfunction. Your heart is no longer working as it should.
The scientific understanding of COVID-19 as well as guidelines for its prevention and treatment are constantly changing. There may be new information since this article was published. It’s important to check with sources like the CDC for the most up-to-date information.