Keep reading for everything you need to know about the influenza virus, commonly known as 'the flu'.
What is the flu?
Although frequently confused with the common cold, influenza or ‘the flu’ is a completely different illness1. The symptoms of the flu are more severe and lasts longer than a cold1.
The flu is a contagious viral infection that affects the respiratory system (nose, throat and lungs) and is caused by the influenza virus1,2.
The flu may be confused with the stomach flu, which causes vomiting and diarrhea2. Influenza does not cause these two symptoms2.
The influenza virus has three main types of viruses – types A, B and C3. 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 B3.
The flu could be life-threatening to certain people who are at a higher risk of developing complications2. 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 gradually2.
Early signs of the flu include a sore throat, headache, runny or blocked nose and sneezing2.
Other symptoms like tiredness, body aches, moderate to high fever and chills are also common with the flu2.
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 air2.
These droplets are minute enough to be inhaled and could infect the person who inhales it2.
The virus could also spread through touch2. 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 strain2.
However, the antibodies against flu viruses you have encountered in the past cannot protect you from new influenza subtypes3. This is because the new virus subtypes can be very different from the subtypes you had before2.
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 complications3.
These high risk groups include3:
- 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 pneumonia2. Pneumonia can be life threatening to older adults and people with a chronic illness2.
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 drink3,2.
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 category2.
Incubation and infectious period
The symptoms usually take around 1-4 days to appear1. Adults can be infectious from 1 day before the onset of symptoms till 5 to 7 days after onset3. Children and persons with weakened immune systems may be infectious for longer periods of time3.
Annual influenza vaccination is recommended to protect against influenza, especially for individuals belonging to populations at higher risk of complications of influenza3.
Here are some practical tips to prevent catching and spreading the flu3:
-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 unwell4.
With effect from 1st January 2014, those in this high-risk category can use Medisave for influenza vaccinations3.
We hope this article provided you with the essential information about the flu.
- WebMD; Influenza; Available at http://www.webmd.com/cold-and-flu/tc/influenza-topic-overview; last viewed 23/05/14.
- Mayo Clinic; Influenza; Available at http://www.mayoclinic.org/diseases-conditions/flu/basics/definition/con-20035101; last viewed 23/05/14.
- Ministry of health; Influenza; Available at http://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 http://www.hpb.gov.sg/HOPPortal/dandc-article/552; last viewed 11/06/14
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