Definition:

Influenza is an infectious disease caused by influenza viruses. Although it is often confused with other influenza-like illnesses, especially the common cold, influenza is a more severe disease than the common cold and is caused by a different type of virus.

Typically, influenza is transmitted through the air by coughs or sneezes, creating aerosols containing the virus. Influenza can also be transmitted by direct contact with bird droppings or nasal secretions, or through contact with contaminated surfaces.

Influenza spreads around the world in seasonal epidemics, resulting in the deaths of between 250,000 and 500,000 people every year, up to millions in some pandemic years.

 Cold or Influenza:

As mentioned above the flu (influenza) is a lot more serious than a common cold. With a cold, the symptoms are centered around the nose and throat. But the flu tends to make the whole body ache the patient is sick all over.

The symptoms of a cold include a runny or blocked nose, sneezing, minor throat irritation, mild fever, sore throat, a feeling that your ears are blocked, and finally coloured mucus or nasal discharge (which means that your immune system is fighting the infection).

Symptoms of influenza usually start suddenly with a high fever and you may feel sick enough to go to bed. Other symptoms include, irritation in the throat or lungs, a dry cough, high fever, shivering, sweating and severe muscle aches. Tests are available to diagnose the flu but there are no such tests for colds.