No one likes getting sick, but understanding the stages of the flu can help you recognize the symptoms early and get on the road to recovery faster. The flu moves through several phases, each with its own set of challenges. The 2026 flu season is breaking records; this year, find out how the flu progresses, when to seek treatment, and how Xpress Wellness Urgent Care is here to help. 

Stage 1: The Sneaky Start

At first, the flu might feel like a simple cold. You may have a sore throat, mild body aches, or a little fatigue. Some people may also experience nausea, vomiting, or diarrhea at the start of their flu infection. But unlike the cold, flu symptoms tend to hit harder and faster. If you start feeling unusually rundown, a flu test can determine if you’re dealing with influenza. If you test positive for the flu, rest up and stay hydrated — your body is gearing up for a bigger battle. 

Stage 2: The Full-On Flu 

Symptoms of the flu peak within a day or two of their onset. Fever, chills, body aches, cough, and fatigue are in full force, making even simple tasks feel exhausting. The flu is most contagious during this phase, so limit exposure by staying home and resting. Continue to drink lots of fluids and take pain and fever relievers as needed. If you have a high fever, worsening symptoms, or experience difficulty breathing, a visit to can help you manage the worst of it.