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Asthma, Allergies, and COVID-19 Explained

May 27, 2021
by Jane E. Dee

Throughout the pandemic, having asthma was considered a risk factor for severe COVID-19. But new data show that people with asthma are relatively protected from severe COVID-19, said Geoffrey Chupp, MD, professor of medicine in the Section of Pulmonary, Critical Care & Sleep Medicine (Yale-PCCSM) at Yale School of Medicine (YSM).

“We looked at 8,000 hospital admissions of patients with COVID-19, and we found that the patients who were diagnosed with asthma - about 10% of the patients - were more likely to survive compared to those people who didn’t have asthma,” Chupp said. He emphasized that the patients had asthma, not smoking-related lung diseases such as emphysema and COPD.

It’s possible that some of the medications used for asthma helped to reduce the inflammation that COVID-19 causes, Chupp said. It’s also likely that the type of immune response most asthmatics have, the allergic response, protected them from severe lung damage, he added.

However, after these patients recovered from COVID-19, their asthma became reactivated. “As they healed, their natural immune response came back with more activity,” explained Chupp. “We’re seeing a fair amount of post-COVID uncontrolled asthma. Most people do well but some have this persistence, a kind of long-hauler problem, although most of them will get better with time.”

Chupp is the director of the Yale Center for Asthma and Airway Disease (YCAAD) at Yale-PCCSM where he and his team provide comprehensive, multidisciplinary treatment. They also take part in translational and clinical trials that look at the effectiveness of novel therapies to improve lung function and quality of life for asthma patients.

Chupp leads several investigations, including the study of a drug that targets a mediator of inflammation. “We’re developing a biologic drug against this target and have teamed up with a biotech company,” Chupp said. “We started this before the pandemic, and we’re hoping to continue with the project and to get it into further development.”

A clinical study sponsored by the National Heart, Lung, and Blood Institute, called the Precision Interventions for Severe and/or Exacerbation-Prone Asthma Network (PrecISE), uses personalized medicine to treat severe asthma. Patients with severe disease receive one of six different treatments based on their type and style of asthma. “If they respond to the drug they stay in the trial and continue to receive treatment,” Chupp said. “If they don’t, they get switched to a different treatment.”

“We’ve been very successful at recruiting for this trial during the pandemic,” Chupp said. “In order to do that we really had to make sure that the patients felt safe. They all get COVID tested before they come in. Even though we are vaccinated, our staff has very strict rules to make sure that the patients and the staff are safe.”

Asthma, Allergies & Pollen

May is National Asthma and Allergy Awareness Month, and for good reason. With spring comes an increase in tree, grass and weed pollen, which often causes allergy symptoms and asthma flare-ups for many people with chronic asthma.

“When yellow pollen dust is everywhere, you know it’s going to be a busy time in the asthma clinic,” said Lauren Cohn, MD, associate professor of medicine (Yale-PCCSM) and a pulmonary specialist at YCAAD.

In recent years, lung disease specialists such as Cohn have recognized that asthma is not a single disease, and that allergies are not the only reason people who have asthma suffer. In fact, most flares of asthma are caused by respiratory infections like the common cold, Cohn said. “Air pollution is an irritant for all asthmatics because it increases inflammation of the bronchial airways,” she added.

“Allergies can bother asthmatic patients year-round. Some asthmatics are worse in the fall during ragweed season. Other weather-related conditions that affect asthmatics include rapid changes from warm to cold or vice versa, or hot, humid weather in the summer,” Cohn said. “This spring we are seeing more asthmatics suffering from allergic disease than last year, possibly because the pollen is worse, or because there are more people outdoors due to relaxation of the pandemic restrictions.”

During the pandemic, her patients had fewer asthma flare-ups than in past years, Cohn said. “We think this is due to mask-wearing and limited human-to-human contact at work and school. This led to much fewer viral respiratory infections. In fact, we saw very few cases of the common cold this year and practically no influenza. These are infections that may cause an asthmatic to come to the hospital or be admitted.”

Jose Gomez Villalobos, MD, assistant professor of medicine (Yale-PCCSM) is among the members of YCAAD. He is a physician-scientist who integrates clinical care of patients with asthma with cutting-edge research.

“We reassess every new patient, making sure that their diagnosis is correct. Pulmonary function tests that are not routinely performed, are done at our center,” Gomez Villalobos said. “If we identify an issue that needs to be addressed, we work with our colleagues to conduct comprehensive evaluations of patients with complicated asthma.”

The center works closely with specialists throughout YSM, including Allergy & Immunology, Otolaryngology (Ear, Nose and Throat), Digestive Diseases (gastroenterology), and Occupational & Environmental Medicine.

“If someone has asthma, and they are constantly having trouble controlling their symptoms or are being limited because of their symptoms, they don’t have to suffer through that,” Gomez Villalobos said.

The Section of Pulmonary, Critical Care and Sleep Medicine is one of the eleven sections within YSM’s Department of Internal Medicine. To learn more about Yale-PCCSM, visit PCCSM’s website, or follow them on Facebook and Twitter.


Submitted by Jane E. Dee on May 27, 2021