What is the flu?

The flu is an illness caused by a virus called influenza. It spreads between humans as infected people cough or sneeze, releasing infectious virus particles into the air.1

Simple hygiene practices such as covering your nose when sneezing and regularly washing your hands can help to minimize the spread of flu;2 however, these measures are not always enough.

The flu causes a range of different symptoms, leaving people feeling very unwell.3,4

Many of these symptoms can also be caused by other illnesses, such as a cold, which can create ‘conflusion’ as you try to figure out if you actually have the flu or not.

How many people does the flu affect?

Globally, up to one billion cases of the flu are estimated to occur each year.5 Of these, up to 5 million cases are deemed severe, resulting in up to 650,000 deaths.6

Is the Flu a serious illness?

Many people believe that the flu is a minor illness that does not have any serious consequences.7–9 In reality, the flu can cause a wide range of severe complications, which in some cases can be life-threatening. These can include:4

  • Inflammation of the brain
  • Blood poisoning (sepsis)
  • Pneumonia
  • Worsening of existing health problems, such as asthma
  • Inflammation of the heart
  • Inflammation of the muscle
  • Multiple organ failure

In the USA alone, up to 960,000 people are hospitalized with the flu each year, resulting in up to 79,000 deaths.10