Respiratory virus infections cause a majority of asthma exacerbations in the fall to spring months. Current diagnostic platforms for respiratory viruses have limitations including cost, availability, and invasiveness. The use of noninvasive breath collection to analyze breath metabolites may be used to differentiate virus-infected asthmatics from other causes of acute asthma exacerbations.

Inclusion Criteria:

• Asthma, Age ≥12, Symptoms/signs of an early asthma exacerbation, Ability to provide exhaled breath condensate (EBC) x15 min, Body mass index (BMI) ≥18

Exclusion Criteria:

• Chronic lung diseases other than asthma (e.g., chronic obstructive pulmonary disease [COPD], lung cancer, fibrotic lung disease, etc.), Smoking in the past 7 days, Eating or non-clear liquids <4 hrs prior to EBC collection, Pregnancy

Patients with asthma with or without an acute exacerbation will be recruited