Every year, people with asthma brace for seasonal colds and flu, which can aggravate wheezing and coughing. Asthma, a common long-term lung condition, can cause difficulty breathing and shortness of breath and accounts for 9.8 million doctor visits and 1.8 million hospital visits in the United States per year.

This year, people with asthma also have COVID-19 to worry about. Like other coronaviruses, the new coronavirus that causes COVID-19 attacks the respiratory system, has infected over 135,00 people and killed nearly 5,000 as of March 13. According to health officials, those most at risk are older populations or people with pre-existing medical conditions. Now, many sufferers of asthma are asking themselves whether their condition puts them at a higher risk.

The World Health Organization (WHO) says yes. It lists asthma, along with diabetes and heart disease, as conditions that make someone “more vulnerable to becoming severely ill with the virus.” The Asthma and Allergy Foundation of America also lists asthma as a chronic medical conditions which makes one more at risk, noting that asthmatics should “take precautions when any type of respiratory illness is spreading in their community.”

But experts told TIME there is little definitive evidence to say whether asthma increases the likelihood of catching the virus or of experiencing more severe illness. “The data that we have so far from China and South Korea does not identify people with asthma as being at risk of getting the virus or having more severe illness with the virus,” Sebastian Johnston, a professor of respiratory medicine & allergy at the U.K. National Heart and Lung Institute tells TIME.

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David Jackson, a consultant respiratory physician and clinical lead for asthma care at Guy’s Hospital in London also says that “asthma currently doesn’t seem to be a significant risk factor for a more severe infection,” adding that the new coronavirus does not seem to be affecting asthmatics in the same way as other viruses generally.

Research on COVID-19 is at a very preliminary stage, but one study of 140 infected patients found that SARS-CoV-2, the virus that causes the illness, has no effect on asthma. With that said, asthma has worsened with other strains of coronavirus.

However, while studies have not yet shown a link between asthma and more severe cases of COVID-19, asthmatics are at risk of more severe illness with respiratory viruses in general—and some experts say people with asthma should make additional provisions.

Johnston says people with asthma should follow all recommended precautions—such as social distancing, avoiding contact with people who have respiratory symptoms, and washing hands—but added that all asthmatics, even those with mild symptoms, should be taking their preventer inhalers “diligently” as a precautionary measure. They should also carry Ventolin—their blue reliever inhalers—with them in case of an asthma attack. Older viruses like the seasonal flu remain a threat, he notes, and people with asthma should get the seasonal flu vaccine.

Please send any tips, leads, and stories to virus@time.com.

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