Key takeaways:
Current evidence does not link mild to moderate asthma with higher rates of infection or poorer outcomes from COVID.
But COVID infection can worsen asthma symptoms in people with asthma. This is true even with mild to moderate COVID illness.
If you have asthma and get a COVID infection, continue to take your asthma medication as normal. And get medical care if your condition worsens.
The best ways to prevent severe illness from COVID infection are to keep up to date with your COVID vaccines, practice good hand hygiene, and follow your asthma treatment plan.
Some people have a higher risk of severe infection from the virus that causes COVID. This is true for people over the age of 65. And it’s the case for people who have one or more chronic medical conditions, like chronic obstructive pulmonary disease (COPD).
But what about the millions of people living with asthma? Asthma is one of the most common types of chronic lung disease. It affects 1 in 12 people in the U.S. With asthma, the airways in the lungs become inflamed and swollen, making it harder to breathe.
Like the common cold and other upper respiratory tract infections, COVID can worsen symptoms of asthma. But it turns out that people with asthma do not have a higher risk for worse outcomes when it comes to COVID. Here’s what the research shows.
Early on in the pandemic, there was concern that the virus that causes COVID might affect people with asthma more severely. That’s because this is the case for people with other respiratory diseases, like COPD and idiopathic pulmonary fibrosis.
But time and data have shown that there is not a much higher risk of a worse COVID outcome in most people with asthma. The CDC lists moderate to severe asthma as a risk factor for severe COVID. But the American Academy of Allergy, Asthma, and Immunology argues that there are not good studies to support this.
Some data show that only people with more “active” asthma (people who needed clinical care for their asthma in the last year) have a higher risk for worse COVID outcomes. But other studies have found that people with asthma actually have a lower risk of severe disease with COVID.
Why is there such a difference in findings? One reason might be due to the fact that people with different types of asthma may react differently to the virus that causes COVID.
Take allergic asthma, the most common type of asthma. People with allergic asthma have a lower risk for severe disease from COVID compared with people who have nonallergic asthma. It’s possible that allergic asthma might even protect people from severe COVID compared to people who don’t have asthma.
Researchers are still trying to understand why this is so. But there’s evidence that the type of inflammation that causes asthma can also work against COVID and prevent severe disease.
And then there’s the fact that asthma severity varies a lot from person to person. People with mild, well-managed asthma tend to have better COVID outcomes than people with hard-to-control or severe asthma. But there’s some evidence that severe asthma might be a risk factor for severe disease with COVID. Though more studies are needed.
So, if you have asthma, it’s especially important to make sure your symptoms are well managed when there are high rates of COVID infection.
No, people with asthma do not seem more likely to get COVID infection. An analysis of 150 studies found no increased frequency of COVID infections in people with asthma. It actually found that the risk of COVID in people with asthma might be lower.
Another review of over 50 studies found that people with asthma had a lower risk of catching the virus that causes COVID in the first place, compared to people who don’t have asthma.
There are several possible reasons for this surprising finding:
There are fewer ACE2 receptors. These receptors are the body’s docking stations for the COVID virus. They’re what lets the virus enter the body’s cells and cause illness. People with asthma seem to have fewer ACE2 receptors in their lungs. So, fewer receptors may mean that less virus enters the body.
Inflammation may be protective. Chronic allergies (including allergic asthma) involve an immune pathway known as type 2 inflammation. This inflammation (when there’s no infection) is what contributes to symptoms of asthma. But it turns out that the cells involved in type 2 inflammation are especially effective against COVID. So the chronic inflammation from allergic asthma might make it harder for the virus that causes COVID to replicate in the lungs.
Inhaled steroids may help. People with asthma often take inhaled corticosteroid medication. This treatment may also work to lower symptoms of COVID infection. But more research is needed to better understand this link.
Getting COVID illness can lead to worsening asthma symptoms in people with asthma. That’s the case even with mild to moderate cases of COVID illness.
One study found that people with asthma had more asthma flare-ups and needed more medication to manage their asthma compared to people who did not have COVID infection. A study from Hong Kong showed the same link.
And even after recovering from mild to moderate COVID illness, people with asthma were more likely to develop hard-to-control asthma or need more asthma medication to manage their symptoms.
Researchers are still trying to understand if COVID infection can cause new asthma. Some people can develop lingering respiratory symptoms after COVID that seem similar to asthma.
Long COVID is when symptoms of COVID linger for weeks or months after the initial infection. When long COVID involves the lungs, some people experience shortness of breath, wheezing, and cough. There’s some evidence that a small percentage of these people might actually develop new asthma. But more research is needed to understand if COVID is causing new asthma or if the breathing symptoms are just part of long COVID.
Any infection in the lung — including a common cold — can trigger an asthma attack. This is when the smallest airways in the lung tighten up and let very little air through. It’s this airway tightening that causes classic asthma symptoms, like:
Shortness of breath
Wheezing
Tightness in chest
Cough
In mild COVID infections, the virus affects mostly the upper airways, like the nose and throat. Typical symptoms of this type of COVID infection are similar to a cold: stuffy nose, sneezing, and sore throat. Mild COVID infections can usually be managed at home — including people with asthma.
In more serious COVID infections, the virus can cause widespread lung inflammation. It can even lead to pneumonia. And the virus can infect the bloodstream, leading to damage in the heart, kidneys, intestines, or brain.
With a moderate to severe COVID infection, a person with asthma may need emergency treatment in the hospital with oxygen, nebulizers, and corticosteroids. Some people may also need specific therapies for COVID illness, like Paxlovid (nirmatrelvir / ritonavir).
Most people with asthma have an action plan that tells them how to manage their asthma on a daily basis, what to do when it worsens, and when to get medical attention. Severe breathlessness and low oxygen levels are examples of when to get medical attention if you have asthma and COVID infection.
Since COVID infection can lead to symptoms similar to asthma, certain inhalers used to treat asthma might be prescribed to people with COVID illness.
By reducing inflammation in the airways, inhalers can help with symptoms of COVID. But there’s not enough evidence yet to recommend inhalers to everyone with a COVID infection. Several clinical trials are underway to study this. If you’re already using an inhaled steroid for asthma and you’re diagnosed with COVID infection, it’s recommended that you continue the inhaled steroid medicine.
Everyone should take steps to prevent the spread of COVID. This includes people with asthma, even if the risk may not be as high as originally thought. Here are some recommendations from the CDC to lower your risk of COVID infection:
Stay up to date with your COVID vaccine.
Improve ventilation and spend time outdoors when possible.
Wash your hands often with soap and water.
Avoid contact with people who have known or suspected COVID infection.
Wear a mask, especially in crowded settings.
Avoid crowds during times of high spread of COVID in your community.
Regardless of how severe your asthma is, the best way to protect yourself if you get COVID illness is to actively manage your asthma and asthma symptoms. Follow these simple steps:
Keep taking your daily inhalers exactly as prescribed to prevent an asthma attack.
Keep your fast-acting bronchodilator (such as albuterol) with you every day, in case your asthma symptoms get worse.
Plan for an emergency supply of medications with your provider.
Make sure you have an asthma action plan to help you recognize and manage asthma symptoms if and when you experience them.
Get a peak flow meter (from a pharmacy) and keep a diary of your peak flows and your symptoms. This can help track your symptoms and tell you how well your asthma is managed. It can also help your medical team assess you over the phone or video.
Anxiety and stress can make asthma symptoms worse. Take steps to help manage your emotions.
For most people with asthma, asthma is not a risk factor for getting COVID or having a more severe COVID illness. It’s even possible that having asthma may even make you a little less likely to get a COVID infection in the first place. But people with severe or hard-to-control asthma may be at higher risk for experiencing more serious COVID symptoms.
Whatever type of asthma you have, it’s likely that getting COVID will make your symptoms worse, even with a mild or moderate case. The best way to protect yourself is to keep up to date with your COVID vaccines, mask in (or avoid) crowded areas, and follow your asthma treatment plan.
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