Dissecting Human Immune Responses to Infection With Influenza or SARS-CoV-2

The purpose of this study is to evaluate the virus-specific immune response in people who are symptomatic with confirmed influenza or COVID-19. We will study the immune response of people who have and who have not been vaccinated with the seasonal influenza and COVID-19 vaccines within the past year. All participants will have data collected and blood, saliva, and nasal swabs performed at five separate visits; 1) at study enrollment, 2) on study day 7, 3) on or between study days 10 to 28, 4) on study day 90, and 5) on study day 180. For participants who agree to the optional sub-study, bronchoscopy with bronchoalveolar lavage (BAL) and endobronchial biopsy (EBBx) will be performed once between study days 10 and 28 and once at study day 180. As part of the bronchoscopy procedure, two chest x-rays will be performed. The bronchoscopy and chest x-ray procedures are not required for participation in the study.