Shortness of breath can make it hard to breathe deeply. You may feel winded, or as if you can’t get enough air into your lungs.

Known clinically as dyspnea, shortness of breath is one of the hallmark symptoms of COVID-19, the disease that’s caused by the new coronavirus known as SARS-CoV-2.

Unlike many other conditions that can cause shortness of breath, this symptom can persist and quickly escalate in people with COVID-19.

Keep reading to learn more about what to watch out for with this symptom, how to differentiate it from other causes, and when to get medical attention for shortness of breath caused by the new coronavirus.

Shortness of breath can make it hard to breathe. It can leave you gasping for air.

Your chest may feel too tight to inhale or exhale fully. Each shallow breath takes greater effort and leaves you feeling winded. It can feel like you’re breathing through a straw.

It may happen when you’re active or resting. It can come on gradually or suddenly.

High intensity or strenuous workouts, extreme temperatures, and high altitudes can all cause shortness of breath. Anxiety can also lead to changes in your breathing rate and pattern.

How does anxiety affect shortness of breath?

Acute stress or anxiety can trigger your biological fight-or-flight response. Your sympathetic nervous system reacts by launching a cascade of physiological responses in response to a perceived threat.

For instance, your heart may race, your breathing may become rapid and shallow, and your vocal cords may constrict when you try to breathe.

The reason your breathing becomes faster and more shallow is because the muscles in your chest take over much of the work of breathing.

When you’re more relaxed, you breathe mostly with the help of your diaphragm, which allows you to take deeper, fuller breaths.

COVID-19-related shortness of breath usually occurs a few days after initial infection. However, some people may not develop this symptom at all.

On average, it sets in between day 4 and 10 of the disease course. It typically follows milder symptoms, such as:

According to doctors’ observations while working in a clinic, the onset of shortness of breath, along with sudden drops in oxygen saturation after very little exertion, may help clinicians distinguish COVID-19 from other common illnesses.

Shortness of breath on its own usually rules out COVID-19. But when it occurs with other key symptoms, such as fever and cough, the likelihood of having an infection with SARS-CoV-2 increases.

The Centers for Disease Control and Prevention (CDC) reports that 31 to 40 percent of people with confirmed cases of COVID-19 have experienced shortness of breath.

The occurrence of other symptoms is as follows:

  • fever: 83 to 99 percent
  • cough: 59 to 82 percent
  • fatigue: 44 to 70 percent
  • loss of appetite: 40 to 84 percent
  • sputum production: 28 to 33 percent
  • muscle, body aches: 11 to 35 percent

Another CDC study of confirmed cases in the United States found that shortness of breath occurred in about 43 percent of symptomatic adults and 13 percent of symptomatic children.

In healthy lungs, oxygen crosses the alveoli into tiny, nearby blood vessels known as capillaries. From here, oxygen is transported to the rest of your body.

But with COVID-19, the immune response disrupts normal oxygen transfer. White blood cells release inflammatory molecules called chemokines or cytokines, which in turn rally more immune cells to kill SARS-CoV-2-infected cells.

The fallout from this ongoing battle between your immune system and the virus leaves behind pus, which is made up of excess fluid and dead cells (debris) in your lungs.

This results in respiratory tract symptoms such as coughing, fever, and shortness of breath.

You may be at a higher risk for developing breathing issues with COVID-19 if you:

According to a review of 13 studies published in the Journal of Infection, having shortness of breath poses a greater risk of severe and critical disease outcomes with COVID-19.

While close monitoring at home is often recommended for mild cases of breath shortness, the safest course of action is to call your primary care doctor if you’re unsure of what to do.

Persistent or worsening shortness of breath can lead to a critical health condition known as hypoxia.

When you can’t breathe properly, it can cause your oxygen saturation levels to drop below 90 percent. This can deprive your brain of oxygen. When this happens, confusion, lethargy, and other mental disruptions may occur.

In severe cases, if oxygen levels dip to around 80 percent or lower, there’s an increased risk of damage to vital organs.

Ongoing shortness of breath is a symptom of pneumonia, which can progress to acute respiratory distress syndrome (ARDS). This is a progressive type of lung failure in which fluid fills up the air sacs in your lungs.

With ARDS, breathing becomes increasingly difficult as stiff, fluid-filled lungs have a harder time expanding and contracting. In some cases, help breathing with mechanical ventilation is needed.

When to get medical care

Below are some of the warning signs to watch out for that may indicate a progression to ARDS or other serious respiratory conditions:

  • rapid, labored breathing
  • pain, tightness, or discomfort in your chest or upper abdomen
  • blue or discolored lips, nails, or skin
  • a high fever
  • low blood pressure
  • mental confusion
  • a rapid or weak pulse
  • cold hands or feet

Get immediate medical attention if you have these or other serious symptoms. If possible, call your doctor or hospital in advance so they can give you instructions on what to do.

Some lung damage caused by COVID-19 may slowly and fully heal. But in other cases, people who recover from COVID-19 may face chronic lung problems.

These lung injuries may cause the formation of scar tissue known as pulmonary fibrosis. Scarring further stiffens the lungs and makes it harder to breathe.

Besides COVID-19, many other health conditions can trigger shortness of breath. Here are some of the most common:

  • Asthma. This obstructive lung disease causes the lining of your airways to swell, nearby muscles to tighten, and mucus to build up in your airways. This blocks the amount of air that can pass into your lungs.
  • Chronic obstructive pulmonary disease (COPD). COPD is a group of progressive lung diseases, the most common of which are emphysema and chronic bronchitis. They can restrict your outward airflow, or lead to swelling and narrowing of the bronchial tubes, as well as mucus buildup.
  • Myocardial infarction. Also known as a heart attack, it can decrease blood and oxygen flow to and from your heart and lungs. This can lead to congestion in these organs, making it harder to breathe.
  • Interstitial lung disease (ILD). ILD includes more than 200 conditions that affect the airways, blood vessels, and air sacs inside your lungs. ILD leads to scarring and inflammation around the air sacs in your lungs, which makes it harder for your lungs to expand.

A variety of health conditions can trigger shortness of breath. On its own, it’s unlikely to be a symptom of COVID-19. Shortness of breath is more likely to be a warning sign of COVID-19 if it’s accompanied by a fever, cough, or body aches.

On average, shortness of breath tends to set in around 4 to 10 days after you contract an infection with the new coronavirus.

Shortness of breath may be mild and not last long. But, in other cases, it may lead to pneumonia, ARDS, and multi-organ dysfunction or failure. These are potentially life threatening complications.

All episodes of shortness of breath must be taken seriously. Be sure to call your doctor right away if you have any concerns about how to manage this symptom.