INTRODUCTION
Since the end of February 2020 Italy, first non- Asian Country, has reported an ever increasing number of COronaVIrus Disease 19 (COVID-19) patients, which has reached over 200,000 confirmed Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) infected subjects and resulted in more than 34000 deaths (data updated to June 19th, 20201). The SARS-CoV-2 infection has spread all over the world becoming one of the biggest pandemics of the last centuries. COVID-19 clinical manifestations spectrum ranges from mild to critical, including diffused interstitial pneumonia, respiratory failure, shock, or multiorgan dysfunction, leading to death in about one third of hospitalized patients 2 with a overall case-fatality rate in the general population of about 7% of infected subjects3.
Patients with chronic pulmonary diseases, such as asthma and chronic obstructive lung disease (COPD), are potentially more severely affected by by SARS-CoV-2 infection 4. Indeed, it is well established that respiratory viral infections are associated with severe adverse outcomes in patients with asthma, including increased risk of asthma exacerbation episodes 5. In addition, it has been suggested that type 2 immunologic profile, which characterizes a large proportion of asthmatic patients, is associated with impaired antiviral immune response 6 and a greater expression in airway epithelial cells of molecules associate with SARS-CoV-2 infectivity 7. Nonetheless, according to the epidemiological studies published so far, chronic pulmonary diseases are not amongst the most common clinical conditions in COVID-19 patients, ranging from 0.3 to 2.5% 8-10.
A proportion of asthmatics, accounting about 5-10% of entire asthma population, continue to experience symptoms and exacerbations despite treatment with high-dose inhaled corticosteroids (ICS) in combination with other controller drugs and/or chronic use of oral corticosteroids (OCS): these are considered severe asthma patients 11. Given the deranged immunological responsiveness that characterizes severe asthma patients, one would expect increased vulnerability to SARS-CoV-2 infection. No data is available on the susceptibility of severe asthmatics to COVID-19 infection and on the clinical outcomes of the infection in these patients. Real-life, registry-based observatories are a unique opportunity to rapidly collect clinical information on the impact of COVID-19 on large populations of severe asthmatics.
The aim of the this study was to investigate the incidence of COVID-19 infection in the population of the Severe Asthma Network in Italy (SANI), one of the largest registry for severe asthma worldwide12,13, and in an additional Center (Azienda Ospedaliero Univeristaria di Ferrara, Ferrara, Italy); we also aimed to describe their clinical characteristics and clinical course of COVID-19 disease.