LAUSR

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to a worldwide pandemic. People with airways disease are at higher risk of respiratory infection, and viruses can trigger respiratory exacerbations. Patients with airways disease may therefore be more susceptible to SARS-CoV-2 infection, development of covid-19, or be at higher risk of adverse outcomes. Here we review susceptibility, based on current epidemiological studies, and explore biological mechanisms. Evidence from multiple large observational studies has shown chronic obstructive pulmonary disease (COPD) is a significant risk factor for covid-19 related mortality. Whether people with asthma are more susceptible to infection or severe outcomes has been much debated but appears to be related to their asthma phenotype and severity. To what extent these differences are biological or influenced by public health non-pharmacological interventions is difficult to quantify. Biological mechanisms that may influence susceptibility and adverse outcomes in airways disease include the increased expression of protein receptors enabling viral cell entry, dysfunctional epithelial airway immunity, type-2 inflammation and the use of inhaled corticosteroids. A better understanding of the susceptibility and mechanisms is essential for developing preventative and therapeutic strategies. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).