What is the flu?
Although frequently confused with the common cold, influenza or ‘the flu’ is a completely different illness.1 The symptoms of the flu are more severe and lasts longer than a cold.1
The flu is a contagious viral infection that affects the respiratory system (nose, throat and lungs) and is caused by the influenza virus.1,2
The flu may be confused with the stomach flu, which causes vomiting and diarrhea.2 Influenza does not cause these two symptoms.2
The influenza virus has three main types of viruses – types A, B and C.3 The virus types A and B are associated with annual outbreaks and epidemics, while type C is associated with mild sporadic illness and occurs less frequently than Types A and B.3
The flu could be life-threatening to certain people who are at a higher risk of developing complications.2 More details on this later-on.
Symptoms of the flu
The symptoms of the flu appear quite suddenly, as opposed to a cold where the symptoms would appear gradually.2
Early signs of the flu include a sore throat, headache, runny or blocked nose and sneezing.2
Other symptoms like tiredness, body aches, moderate to high fever and chills are also common with the flu.2
How does the flu spread?
The flu spreads quite rapidly and easily through direct contact. When an infected person talks, sneezes or coughs, tiny droplets of saliva and mucus fly into the air.2
These droplets are minute enough to be inhaled and could infect the person who inhales it.2
The virus could also spread through touch.2 For example, your child could get the flu when she touches toys that have been touched by an infected child and then touches her own eyes, nose or mouth.
If you have gotten a certain strain of the flu in the recent past or have been vaccinated for it, then your body might be immune to that particular strain.2
However, the antibodies against flu viruses you have encountered in the past cannot protect you from new influenza subtypes.3 This is because the new virus subtypes can be very different from the subtypes you had before.2
Who’s at a higher risk of developing complications?
Although most healthy children and adults recover from the flu with minimum medication, there are a few people who are at a higher risk of developing complications.3
These high risk groups include:3
- Adults over the age of 65
- Children from 6 months to less than 5 years, pregnant mothers
- Adults and children who have chronic disorders of the lung or heart systems, including asthma
- Adults and children who have required regular medical follow-up or hospitalisation during the preceding year due to chronic metabolic diseases (including diabetes mellitus), renal, neurologic, liver, or blood disorders, or immunosuppression (including immunosuppression caused by medications or the Human Immunodeficiency Virus)
What are the complications of the flu?
Sometimes the flu could lead to complications such as bronchitis, ear infections, sinus infections and pneumonia.2 Pneumonia can be life threatening to older adults and people with a chronic illness.2
When should you see the doctor?
If your child has the flu, keep her away from school, let her get plenty of rest and give her plenty of fluids to drink.3,2
If you have a baby and suspect he has the flu, it is best to show him to the paediatrician as soon as possible2. The same goes for others in the higher-risk category.2
Incubation and infectious period
The symptoms usually take around 1-4 days to appear.1 Adults can be infectious from 1 day before the onset of symptoms till 5 to 7 days after onset.3 Children and persons with weakened immune systems may be infectious for longer periods of time.3
Prevention tips
Annual influenza vaccination is recommended to protect against influenza, especially for individuals belonging to populations at higher risk of complications of influenza.3
Here are some practical tips to prevent catching and spreading the flu:3
-Follow good hygiene practices. Wash your hands regularly with soap and water.
-Avoid crowded places when you are unwell.
-Turn quickly away from anyone and cover your nose and mouth with a tissue when coughing and sneezing.
-Wear a surgical mask if you are unwell.4
With effect from 1st January 2014, those in this high-risk category can use Medisave for influenza vaccinations.3
We hope this article provided you with the essential information about the flu.
References:
- WebMD; Influenza; Available at www.webmd.com/cold-and-flu/tc/influenza-topic-overview; last viewed 23/05/14.
- Mayo Clinic; Influenza; Available at www.mayoclinic.org/diseases-conditions/flu/basics/definition/con-20035101; last viewed 23/05/14.
- Ministry of health; Influenza; Available at www.moh.gov.sg/content/moh_web/home/diseases_and_conditions/i/influenza.html; last viewed 23/05/14.
- Health Promotion Board; Influenza; Available at www.hpb.gov.sg/HOPPortal/dandc-article/552; last viewed 11/06/14
SG/VAC/0002/14a Certified 14/07/14