Influenza, also known as the flu, is an infection caused by influenza viruses.

07 Sep 2018

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Understanding Influenza

Influenza, also known as the flu, is an infection caused by influenza viruses. There are three main types – Type A, Type B and Type C. Influenza A(H1N1-2009), Influenza A(H3N2) and Influenza B are influenza viruses commonly circulating globally and in the community.  Influenza C is associated with mild sporadic illness and occurs less frequently.

How Influenza Spreads

Influenza is spread from person to person mainly through infectious respiratory droplets and secretions released during coughing and sneezing.

Transmission can also occur when secretions of an infected person are transferred from a recently contaminated surface (e.g. doorknob, telephone receiver) to the nose or mouth of a healthy individual.

Adults may be contagious from one day before the onset of symptoms until  5 to 7 days after onset. Children and people with weakened immune systems may be infectious for longer periods of time.


Symptoms can appear quite suddenly, and usually include:

  • Fever

  • Headache

  • Chills

  • Cough

  • Sore throat

  • Muscle aches

  • General malaise and fatigue

Gastrointestinal symptoms, such as nausea, vomiting or diarrhea, can sometimes accompany influenza, especially in children, but these symptoms are rarely prominent.

Influenza can result in pneumonia, hospitalization or even death, especially in populations at higher risk of developing complications of influenza This includes:

  • Persons aged 65 or over

  • Children less than 5 years old

  • Adults and children who have chronic disorders of the lun

  • Adults and children who have required regular medical follow-u

  • Children and adolescents aged 6 months to 18 years old who are receiving long-term aspirin therapy and therefore might be at risk of developing Reye’s syndrome, a swelling in the liver/brain, after influenza infection

  • Pregnant women

  • Residents of nursing homes, intermediate/long-term care facilities

What to do if you think you have influenza

If you suspect you have influenza infection, you should stay home and avoid contact with other people except to seek medical care. Avoid strenuous physical activities such as jogging and running activity during illness until complete recovery.

Most people with influenza have mild illness and do not require medical care or antiviral drugs. If you know you are at a higher risk of flu-related complications, or if you are concerned about the illness, please consult your doctor.

Seek immediate medical attention if you experience the following warning signs:



Breathing difficulties

Breathing difficulties

Pain or pressure in the chest or abdomen

Blueish skin colour


Fever with a rash

Persistent vomiting

Not drinking enough fluids

Sudden dizziness

Not waking up or not interacting

Symptoms of influenza that improve but then return with fever and a worse cough

Being so irritable that they don’t want to be held

Treatment for influenza

Antiviral medications are available for the treatment of influenza. They can help reduce the severity of symptoms, promote recovery and antivirals are most effective within the first two days of illness.

Antivirals can be classified into:

  • adamantanes (e.g. amantadine and remantadine); and

  • ·neuraminidase inhibitors (e.g. oseltamivir and zanamivir)

Protecting against influenza

Seasonal influenza vaccination is recommended to protect against influenza, especially to populations at higher risk of influenza complications. Medisave can be used for influenza vaccinations for persons at higher risk of developing influenza-related complications.

People living and caring for high-risk individuals should also be vaccinated against influenza. Other measures include:

  • Practise good personal hygiene by washing your hands regularly and thoroughly with soap and water, especially before touching your eyes, nose or mouth

  • Cover your nose and mouth with a tissue when coughing or sneez

  • Avoid crowded places and stay home from work/school if you

  • Use a serving spoon when sharing food at meal times

For More Information

  • 1800-225-4122