The Flu: Causes
Exploring the causes of the flu
The flu is an upper respiratory tract infections (URTIs) caused by the influenza virus,2,3 typically types A and B, which cause seasonal epidemics every year.
Type C is detected less often and usually causes mild symptoms.1
Transmission of the Flu
Influenza virus particles are spread from person to person within tiny droplets formed when coughing, sneezing, or talking.4-6
These infected droplets are then transmitted to another person who either:5,6
- Breathes in the airborne droplets
- Comes into close contact with an infected person
- Touches a contaminated surface and then touches their mouth, nose, or eyes
Anyone can get the flu, but it can be more serious in certain groups of people:1
- People aged 65 and over
- Pregnant women
- People with serious medical conditions
- Babies/young children
The Contagious Period
When is a person contagious?
An infected person may be able to spread the flu before even becoming symptomatic.4
The highest point of contagiousness is within the first 3-4 days after the illness begins, but most adults may be considered infective 1 day prior to demonstrating symptoms.4
Healthy adults can be capable of spreading the virus for up to 7 days into their flu episode, but children and immunocompromised patients may be contagious for a longer period.4
Reducing the risk of contracting the flu
Due to the constantly evolving nature of viruses, the composition of the flu vaccine is updated every year as necessary.7 In addition to this, patients can be counselled to reduce their risk of infection and the risk of spreading it to others.
1. Use a tissue to cover coughs and sneezes
Cough or sneeze into a tissue, and then immediately dispose of it.8
2. Wash your hands regularly
Wash your hands regularly and thoroughly with soap and water for at least 20 seconds. If soap and water is not available, use an alcohol-based hand sanitizer.8
3. Avoid touching your face
The flu virus can be caught through the process of “self-inoculation”, which refers to a person touching an infected surface and then transferring virus particles to themselves by touching their eyes, nose, or mouth.5,8
Where possible, avoid touching your face.
4. Routine cleaning
The flu virus can “live” on some surfaces for up to 48 hours. Routine cleaning of surfaces can help to reduce the spread of flu.9
5. Self isolation
Avoiding close contact with people that are ill and early self-isolation of those feeling unwell is recommended.
For those who have been ill with flu symptoms, remaining isolated for at least 24 hours after their fever is gone is also advised.10