What Causes the Flu?

The flu, also known as influenza, is caused by influenza viruses. These viruses belong to the Orthomyxoviridae family and are categorized into different types, including influenza A, B, and C. Influenza A and B viruses are the ones that commonly cause seasonal flu outbreaks in humans.

The flu is highly contagious and spreads primarily through respiratory droplets that are produced when an infected person coughs, sneezes, or talks. It can also spread by touching surfaces or objects contaminated with flu virus and then touching the mouth, nose, or eyes.

The influenza virus has the ability to change over time through a process known as antigenic drift and antigenic shift, which can lead to new strains of the virus emerging. This is why seasonal flu vaccines need to be updated regularly to provide protection against the most current strains of the virus.

Symptoms of the flu typically include:

  • Fever or feeling feverish/chills
  • Cough
  • Sore throat
  • Runny or stuffy nose
  • Muscle or body aches
  • Headache
  • Fatigue
  • Some people may experience vomiting and diarrhea, though this is more common in children

Flu symptoms can range from mild to severe and can lead to complications, particularly in vulnerable populations such as young children, the elderly, pregnant women, and people with certain underlying health conditions.

The best way to prevent the flu is to get vaccinated annually with the flu vaccine. The vaccine helps your immune system build defenses against the most prevalent strains of the virus for that particular flu season. Additionally, practicing good hygiene, such as washing hands frequently, covering coughs and sneezes, and avoiding close contact with sick individuals, can help reduce the risk of infection.

It’s worth noting that the flu is different from the common cold, even though they share some similar symptoms. The flu tends to come on more suddenly and is generally associated with more severe symptoms than the common cold.