Adult-onset asthma induced by COVID-19: A case report.

COVID-19 commonly presents respiratory symptoms that can linger after the acute phase. Asthma onset or exacerbations have been documented after viral infections although rarely in adults. We report a case of adult-onset asthma triggered by mildly symptomatic COVID-19 in a 24-year-old female without previous respiratory issues. Fatigue, exercise dyspnea, and intermittent cough persisting a month after the infection, led to spirometry testing, revealing reduced lung function, with normal CT imaging. Budesonide/formoterol therapy improved symptom control and repeated spirometry testing showed improving but reduced lung function after five months. Methacholine testing was thus conducted and confirmed bronchial hyperreactivity and adult-onset asthma. Clinicians should be attentive to persistent respiratory symptoms and suggest appropriate testing. Further research should focus on underlying mechanisms of this phenomenon.