Influenza, commonly known as the flu, is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe symptoms like fever, cough, sore throat, and body aches, and can lead to serious complications, especially in the young, elderly, or those with underlying health conditions.

The most effective way to prevent the flu is through an annual flu jab (vaccine). The vaccine works by stimulating the body's immune system to produce antibodies without causing the illness. While effectiveness varies each year based on the circulating virus strains, vaccination significantly reduces the risk of illness, hospitalization, and death. It is recommended for nearly everyone aged six months and older.

For those who do contract the flu, antiviral drugs are prescription medicines that can treat the illness. They are not a substitute for the vaccine but are a crucial second line of defense. Drugs like oseltamivir work by stopping the virus from replicating inside the body. To be most effective, they must be started within 48 hours of symptom onset. Antivirals can lessen fever and symptoms, shorten the illness by 1-2 days, and reduce the risk of serious complications, making them particularly important for high-risk individuals.

A balanced diet, good hand hygiene, and staying home to rest remain the most reliable supportive practices.