Clinical Immunology Service, Internal Medicine Department, Faculty of Medicine, Universidade Federal Fluminense, Niterói 24070-035, Brazil.
Basic and Clinical Immunology Unit, Department of Pathology, Faculty of Medicine, University of Porto, Porto 4200-319, Portugal.
Int J Environ Res Public Health. 2021 Jan 26;18(3):1093. doi: 10.3390/ijerph18031093.
Asthma is the most frequent chronic condition in childhood and a current concern exists about asthma in the pediatric population and its risk for severe SARS-CoV-2 infection. Although all ages can be affected, SARS-CoV-2 infection has lower clinical impact on children and adolescents than on adults. Fever, cough and shortness of breath are the most common symptoms and signs in children; wheezing has not been frequently reported. Published studies suggest that children with asthma do not appear to be disproportionately more affected by COVID-19. This hypothesis raises two issues: is asthma (and/or atopy) an independent protective factor for COVID-19? If yes, why? Explanations for this could include the lower IFN-α production, protective role of eosinophils in the airway, and antiviral and immunomodulatory proprieties of inhaled steroids. Additionally, recent evidence supports that allergic sensitization is inversely related to ACE2 expression. Obesity is a known risk factor for COVID-19 in adults. However, in the childhood asthma-obesity phenotype, the classic atopic Th2 pattern seems to predominate, which could hypothetically be a protective factor for severe SARS-CoV-2 infection in children with both conditions. Finally, the return to school activities raises concerns, as asymptomatic children could act as vectors for the spread of the disease. Although this is still a controversial topic, the identification and management of asymptomatic children is an important approach during the SARS-CoV-2 epidemic. Focus on asthma control, risk stratification, and medication adherence will be essential to allow children with asthma to return safely to school.
哮喘是儿童中最常见的慢性疾病,目前人们关注的是儿科人群中的哮喘及其感染严重 SARS-CoV-2 的风险。尽管所有年龄段都可能受到影响,但 SARS-CoV-2 感染对儿童和青少年的临床影响低于成年人。发热、咳嗽和呼吸急促是儿童最常见的症状和体征;哮鸣音并未频繁报道。已发表的研究表明,哮喘儿童似乎没有不成比例地受到 COVID-19 的影响。这一假设提出了两个问题:哮喘(和/或过敏)是否是 COVID-19 的独立保护因素?如果是,为什么?对此的解释可能包括 IFN-α 产生减少、嗜酸性粒细胞在气道中的保护作用以及吸入性类固醇的抗病毒和免疫调节特性。此外,最近的证据支持过敏致敏与 ACE2 表达呈负相关。肥胖是成年人 COVID-19 的已知危险因素。然而,在儿童哮喘肥胖表型中,经典的过敏 Th2 模式似乎占主导地位,这可能是同时患有这两种疾病的儿童严重感染 SARS-CoV-2 的保护因素。最后,重返学校活动引起了人们的关注,因为无症状儿童可能成为疾病传播的载体。尽管这仍然是一个有争议的话题,但识别和管理无症状儿童是 SARS-CoV-2 流行期间的重要方法。关注哮喘控制、风险分层和药物依从性对于允许哮喘儿童安全返回学校至关重要。