Influenza (flu) is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and lungs. Learn about flu, including symptoms, prevention methods, and treatment options.

Dec 19, 2025 · Flu, also called influenza, is an infection of the nose, throat and lungs, which are part of the respiratory system. The flu is caused by a virus. Influenza viruses are different from the "stomach …

Oct 11, 2022 · What is the flu (influenza)? The flu is an illness you get from the influenza virus. It causes symptoms like head and body aches, sore throat, fever and respiratory symptoms, which can be …

1 day ago · A resulting 12-point cold & flu severity index is further broken out into five levels, helping to paint a regional and national picture of influenza activity in the US. The map also provides breakouts …

2 days ago · Moderna’s mRNA flu vaccine gave more protection against illness than the standard flu shot in a phase 3 clinical trial, according to published results.

Jul 15, 2025 · The flu and the common cold may seem very similar at first. Here’s what you need to know to correctly identify the flu and get the treatment you need.

Feb 28, 2024 · The flu, also called influenza, is a respiratory infection caused by viruses. Each year, millions of Americans get sick with the flu. Sometimes it causes mild illness. But it can also be …

Feb 28, 2025 · Seasonal influenza (the flu) is an acute respiratory infection caused by influenza viruses. It is common in all parts of the world. Most people recover without treatment. Influenza spreads …

3 days ago · Flu cases have reached a 25-year high in the US, driven by a mutated H3N2 subclade K strain. CDC data shows record doctor visits for flu symptoms. Experts warn immunity gaps are …