Virus Diseases

The goal of this observational study is to learn if a traditional Chinese herbal medicine (Xuanfei Jiangzhuo Decoction) works to help older adults recover from a COPD flare-up caused by the flu (influenza virus). The main questions it aims to answer are: Does the herbal medicine help participants feel better and recover faster? Does it lower the chance of getting a second infection from bacteria? Is the herbal medicine safe to use? Researchers will compare participants who choose to take the herbal medicine along with their standard flu treatment (Oseltamivir or Baloxavir) to participants who only take the standard flu treatment (Oseltamivir or Baloxavir). Participants will: Take the herbal medicine (a liquid drink) twice a day for 5 days, or just take their standard flu medicine for 5 days. Visit the clinic 4 times over 28 days for checkups and tests. Provide blood and stool samples to help researchers understand how the medicine affects the body and gut health. Answer simple questions about their cough, breathing, and energy levels.