Even while being in the midst of battling the COVID-19 pandemic, here in Singapore, we are about to enter another bout with the flu (influenza) season.

How many flu seasons do we have in a year?

You may wonder why are you hearing its flu season again, having just heard it recently?

"The flu season occurs between the fall and winter seasons around the world. With the Northern and Southern hemispheres, the flu virus is different on both sides of the equator. For us in (un)lucky Singapore, we are right in the middle of both, and thus are affected by both," explains Dr Ling Moi Lin, Director of Infection Prevention & Epidemiology from Singapore General Hospital (SGH), a member of the SingHealth group.

"The months that we (in Singapore) are affected by the flu season typically range from May to July and December to February."

Possible complications from the flu

A severe case of the flu (influenza) can lead to pneumonia, myocarditis (inflammation of the heart) and encephalitis (inflammation of the brain). Other associated complications include bronchitis, sinusitis and middle ear infection.

Read more: Pneumonia - A leading cause of death in Singapore and worldwide

Who are at risk of developing complications from the flu?

  • Children who are six months to five years old, with no underlying medical condition
  • Those with long-term medical conditions such as:
    • Chronic lung conditions such as asthma or chronic lung disease
    • Chronic heart disease
    • Neurologic and neurodevelopmental conditions with muscle weakness, swallowing and breathing problems
    • Diabetes
    • Chronic kidney or liver conditions
    • Blood disorders such as thalassaemia
    • Immune system disorders
    • Extreme obesity
  • Children on long-term aspirin therapy
  • Pregnant women

Why is getting the flu shot important and why must it be done annually?

The influenza vaccine is the best way to keep yourself and others safe from the flu. The more people get vaccinated, the less likely that influenza can spread among a community.

You need a flu shot every year because the influenza virus mutates quickly and frequently. So this year's 'popular' strains of viruses would be different from last year's. This means the flu shot you had last year would not protect you from the current influenza.

Read more: Have been coughing for weeks? This could be the cause

5 Common questions about the flu shot

1) Will I get the flu from the flu shot?

The influenza vaccine contains inactivated virus. And dead viruses can’t make you sick. But they do stimulate your immune system to make antibodies that would protect you from the influenza viruses that you have been vaccinated against.

2) Is it safe to get a flu shot during pregnancy?

Not only is it safe for pregnant women to get the vaccine, it is essential. Because pregnant women have a higher risk of developing complications from influenza. 

3) If I am allergic to eggs, can I still get the flu shot?

Most influenza vaccines contain a small amount of egg proteins because the viruses used to make the vaccines have been incubated in eggs. However, severe reactions in people with egg allergies are rare.

4) Will I be protected from the flu instantly after getting the flu shot?

The flu vaccination takes effect in about 2 weeks, thus it is better to get vaccinated early before flu season starts.

5) If I feel fine, why do I need to get the flu shot?

You can be a carrier of the flu virus and not know it. According to studies, as many as 3 out of 10 people carrying the virus have no symptoms of influenza. This means you can be spreading the virus to others – like your children, elderly parents, friends and co-workers – without knowing it.

Read more: Natural immunity is better than vaccines. True or false?


Articles on HealthXchange.sg are meant for informational purposes only and cannot replace professional surgical, medical or health advice, examination, diagnosis or treatment. Photo courtesy of iStock.