Influenza and Its Vaccine: What You Need To Know

Influenza, commonly known as the flu, is a highly contagious viral infection that affects the respiratory system. The flu is caused by the influenza virus, which can be spread through contact with respiratory secretions, such as saliva or mucus, from an infected person. It can also be spread through contact with objects or surfaces that have been contaminated with the virus.

Types of influenza

There are four types of influenza viruses: A, B, C and D. Influenza A and B are the most common and can cause severe illness in people of all ages. Influenza A also affects other mammalian and avian species. Influenza C generally only causes mild illness. While influenza D mainly affects cattle and does not impose a threat to humans.

Seasonal influenza

Seasonal influenza or seasonal flu is called 'season' as it usually takes place during a specific period each year. However, in a tropical country like Malaysia, influenza can occur anytime throughout the year with peak seasons over certain months.

It is caused by two main types of influenza viruses, type A and type B. These viruses are constantly changing, which is why it’s important for people to get vaccinated every year.

The symptoms of influenza can mimic the common cold which includes:​

• Fever
  
• Cough
  
• Sore throat
  
• Runny nose or stuffy nose
  
• Headache
  
• Body aches
  
• Fatigue
  

In some cases, the flu can also lead to serious complications, such as pneumonia, bronchitis and even death.

Prevention of influenza

The best way to prevent influenza is to get vaccinated every year. In addition to vaccination, you can also reduce your risk of getting the flu by these necessary precautions:​

• Washing your hands often with soap and water
  
• Avoiding close contact with people who are sick
  
• Avoiding touching your eyes, nose or mouth
  
• Cleaning and disinfecting surfaces that may be contaminated with the virus

Why is it important to get an influenza vaccine?

Every year, millions of people around the world suffer from the flu, and many of them require hospitalization due to severe flu. In fact, the flu is responsible for an estimated 291,000 to 646,000 deaths from flu cases each year. The best way to protect yourself from the flu is to get an influenza vaccine. The vaccine helps your body to develop immunity against the virus.

Who needs an influenza vaccine?

It is recommended for everyone starting from six months of age and older. Everyone who wants to lower their risk of getting influenza is recommended to get the flu shot. It is especially important for protection in the high-risk groups listed below as they are more likely to get complications and serious illnesses from the infection.

• Children aged under five years old
  
• Adults 50 years and older
  
• Elderly
  
• Pregnant women
  
• People with chronic medical conditions, such as heart disease, diabetes, asthma and immunocompromised
  
• People with morbid obesity
  
• Individuals living in certain institutional settings
  

People who are frequently exposed to the virus such as healthcare workers and caretakers in long-term care facilities are also recommended to get the vaccine.

The vaccine is also highly recommended by the Saudi Arabia government for pilgrims who are going to perform the hajj or umrah.

Below are related complications that can happen from influenza which are more severe in high-risk patients:​

• Pneumonia
  
• Bronchitis
  
• Ear infection
  
• Sinuses infection
  
• Asthma exacerbation
  
• Worsening of chronic medical conditions, such as congestive heart failure, diabetes and other respiratory illness such as Chronic Obstructive Pulmonary Disease (COPD)

When should I get the vaccine?

Influenza in Malaysia occurs all year round with peak flu season around May-July and November-January. The best time to get the flu shot is before the start of the peak season when an outbreak will likely occur. However, you can still get vaccinated after the peak season as influenza viruses can circulate all year round.

You need it every year to boost your immune system against it because the virus changes over time. The viruses in the vaccine are updated each year to keep up with the changing viruses. Therefore make sure to get your annual flu vaccination every year.

Is the vaccine safe and what are the side effects?

Yes, the influenza vaccine is safe. The most common side effect is soreness at the injection site. Serious side effects are very rare.

The flu vaccine is safe for pregnant women and their developing babies. Pregnant women are at an increased risk of complications from the flu, so it’s important to get vaccinated.

The influenza vaccine is also safe for use in breastfeeding mothers and their babies. Breastfeeding helps protect babies from getting sick.

It is also safe for the children and elderly as well as people with chronic medical conditions, such as heart disease, diabetes and asthma. In fact, getting vaccinated can help prevent serious complications from the flu in these people.

However, if you have a severe egg allergy, you should not get the egg-based influenza vaccine. Talk to your doctor if you have a mild or moderate egg allergy. You may be able to get the vaccine if you take certain precautions, such as taking antihistamines before the vaccine is given.

Another type of influenza vaccine which is a recombinant vaccine or cell-based vaccine may be given to an individual with severe egg allergies.

Can the influenza vaccine give me the flu?

No, the influenza vaccination cannot give you the flu. The inactivated influenza vaccine is made with viruses that have been killed, so it’s impossible to get the flu from this vaccine. The live attenuated influenza vaccine is made with a weakened virus, so it’s also unlikely to cause the flu.

However, you may experience flu-like symptoms such as body aches or fever due to mild side effects of the vaccine which will go away in a few days. This is a sign that your immune system is responding and creating antibodies against the virus.

Available influenza vaccines in Malaysia

1. Fluarix Tetra® (Inactivated influenza vaccine) GlaxoSmithKline Pharmaceuticals (M) Sdn Bhd/GlaxoSmithKline Biologicals, Germany 
   
2. Influvac® (Inactivated influenza vaccine) Abbott Laboratories (M) Sdn Bhd/Abbott Biologicals B.V., Netherlands 
   
3. FluQuadri Quadrivalent™ Sanofi Aventis (M) Sdn Bhd/Sanofi Pasteur Inc., USA 
   
4. Vaxigrip Tetra® Sanofi Aventis (M) Sdn Bhd/ Sanofi Pasteur inc., France
   
5. SKYCellflu Quadrivalent® AJ Biologics (M) Sdn Bhd/SK Bioscience Co., South Korea

How to get an influenza vaccine?

The influenza vaccination is available at most pharmacies and clinics. You don’t need a prescription to get the vaccine.

You can also get the annual influenza vaccination at some workplaces, schools and colleges.

Check with your employer, school or college to see if they offer the influenza vaccine.

Contact us at DoctorOnCall to book an appointment for the influenza vaccine and protect yourself and your loved ones from this illness. Remember, health is wealth.