Recommended by Dr. Povroznik, vice president of Quality and chairman of Infection Control at United Hospital Center
What is Influenza (Flu)?
Influenza, also known as the flu, is a respiratory infection caused by the spread of the influenza virus. The infection mainly affects a person’s nose, throat, and lungs and can come in four main types: Type A, B, C, and D.
Each type of influenza has varying strengths and viral characteristics when it comes to how it can spread. Influenza Type A and Type B are the most common and usually spread among humans each year (flu season). Influenza Type C is less common and less severe, and influenza Type D is usually only seen in animals such as cattle.
How Does the Flu Spread?
The flu is spread from an infected person to a healthy person via water droplets or vapors containing the influenza virus, usually transmitted in a cough, sneeze, or talking within close proximity. The influenza virus can also live briefly on solid surfaces and be transmitted to someone who has touched their eyes, nose, or mouth after touching the contaminated surface. This is one reason why handwashing can be such a powerful preventive measure.
Once the influenza virus enters a person’s system, it begins to attack their respiratory tract. If their immune system cannot fend off the virus, the person will become infected and contagious. The person will quickly begin experiencing symptoms of the infection and will spread the virus further without proper precaution.
What Are Symptoms of the Flu?
Main symptoms of the flu include coughing, sneezing, runny nose, sore throat, headaches, fatigue, and muscle soreness throughout their body. These symptoms usually begin one to two days after a person has had contact with the influenza virus and typically last between two and eight days.
Though some individuals may experience the asymptomatic flu, in which they do not experience any symptoms, others may experience more severe symptoms such as high fever, nausea, vomiting, dizziness, chest pain, and shortness of breath.
The influenza virus can often lead to other more serious health complications such as pneumonia and bronchitis and infection and inflammation in other areas of the body. Preventing influenza can help to prevent the development of these other conditions.
When is Flu Season?
Flu season in the United States typically occurs in the fall and winter months, with some seasons lasting until early spring. Though the influenza virus is present throughout the year, environmental factors such as temperature and low humidity allow the virus to survive longer and be transmitted more quickly in the colder months.
Learn more about the flu vaccine by reading FAQs About Influenza with Dr. Mark Povroznik, Part 2.
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