Related Experiment Video
Updated: Oct 11, 2025

Author Spotlight: Advancements in Multiplex Detection of Respiratory Viruses
Published on: November 10, 2023
COVID-19 Infections and Asthma
Philip A Palmon1, Daniel J Jackson2, Loren C Denlinger1
1Division of Allergy, Pulmonary & Critical Care Medicine, Department of Medicine, University of Wisconsin School of Medicine & Public Health, Madison, Wis.
Abstract:
The severe acute respiratory syndrome coronavirus 2, which causes coronavirus disease 2019 (COVID-19), has infected more than 200 million and led to the deaths of more than 4.3 million people. Although there are known risk factors for severe disease, asthma was initially hypothesized to be a risk factor for severe disease given the association between asthma exacerbations and respiratory viral illnesses in general. Fortunately, clinical outcomes for patients with asthma overall are similar to those for patients without asthma, without convincing evidence that asthma is a risk factor for severe disease. This may be explained in part by the decreasing gradient of angiotensin-converting enzyme-2 receptor from the upper to lower respiratory epithelium and that aeroallergen-sensitized patients with asthma can have up to 50% reduction in angiotensin-converting enzyme-2 receptor expression. Vaccination for patients with asthma is recommended for all without clear contraindications. COVID-19-specific treatment options are available depending on the severity of disease. We caution the use of systemic corticosteroids in patients with asthma not requiring supplemental oxygen given an association with worse outcomes. Postacute COVID-19 syndrome or long-haul COVID does not appear to be more prevalent in the population with asthma, and a multidisciplinary approach to care is a reasonable option.
Related Concept Videos
Asthma-I: Introduction
Asthma-II: Pathophysiology and Classification
Additionally, environmental and genetic factors play crucial roles in determining an individual's susceptibility to asthma and the severity of their condition.
Critical processes in asthma pathophysiology include:
Asthma-III: Symptoms and Complications
Classification of Asthma
Asthma: Pathogenesis and Management
Asthma is classified as allergic and non-allergic. Allergens such as dust mites, pollen, and pet dander trigger allergic asthma, while factors like cold air, intense emotions, or exercise can induce non-allergic asthma.
Asthma-IV: Diagnostic and Management
Clinical Assessment for Asthma:
This is the first step in diagnosing and managing asthma. It includes:
COPD: Pathogenesis and Clinical Features
The primary cause for the onset of COPD is cigarette smoking and exposure to air pollution. These hazardous factors initiate a chain reaction within the lungs, resulting in chronic inflammation, damage to the airways, and a...

