5 days ago · Influenza, acute viral infection of the upper or lower respiratory tract, marked by fever, chills, and a generalized feeling of malaise. Influenza is caused by viruses in the family Orthomyxoviridae. Learn more about the classification of influenza viruses, influenza outbreaks, and influenza symptoms and treatment.

Jan 28, 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 flu" viruses that cause diarrhea and vomiting. Most people with the flu …

6 days ago · WHO fact sheet on influenza: includes key facts, definition, symptoms, transmission, seasonal epidemics, effects, prevention, WHO response.

The meaning of INFLUENZA is an acute, highly contagious, respiratory disease caused by any of three orthomyxoviruses. How to use influenza in a sentence.

Understanding Influenza. Flu is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and sometimes the lungs. It can cause mild to severe illness, and at times can lead to death. The best way to prevent flu is by getting a flu vaccine each year.

Jan 23, 2023 · Influenza is a communicable viral disease that affects the upper and lower respiratory tract. A wide spectrum of influenza viruses causes it. Some of these viruses can infect humans, and some are specific to different species.

Influenza, commonly known as the flu, is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These symptoms begin one to four (typically two) days after exposure to the virus and last for about two to eight days.

Sep 18, 2024 · There are four types of influenza viruses: A, B, C, and D. Influenza A and B viruses cause seasonal epidemics of disease in people (known as flu season) almost every winter in the United States.

Influenza (Flu) Influenza (flu) is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and lungs. View All

Nov 27, 2009 · Influenza is an acute viral infection that primarily attacks the upper respiratory tract, including the nose, throat, bronchi and, less frequently, the lungs. The disease occurs worldwide and spreads very quickly in populations, especially in crowded circumstances.