This study tests Xuanfei Baidu Granule, a Chinese medicine, for treating Influenza A (a type of flu) to see if it's safe and effective. A total of 584 people will join, divided into four groups. Each group gets different treatments: some will take Xuanfei Baidu Granule alone, others will take it with another medicine called Baloxavir Marboxil, and some will get a placebo (a fake treatment to compare results). The granule is taken twice daily with hot water for 5 days, while Baloxavir Marboxil is taken once for a day.

Participants must be between 18 and 65 years old, recently diagnosed with Influenza A, and able to follow study procedures. Visits happen every day for a week. Certain health conditions and recent medication use can exclude you from the study.

• Duration: Daily visits for 7 days.
• Eligibility: Must be 18-65 years old and recently diagnosed with Influenza A.
• Risks: Allergy to study drugs, other health conditions may exclude participation.