Myth vs. Fact on Cold & Flu <3>

Myth #15:  “Flu shots only work if they’re a perfect match.”

Fact: Even when the vaccine isn’t a perfect match, it still helps reduce severe illness, hospitalization, and death.

Myth #16:  “Flu season only happens in winter.”

Fact: Flu is most common in winter in temperate regions, but it can occur in other seasons and can spread year‑round in tropical areas. Winter conditions that help flu spread include:

• Cold, dry air that keeps the virus stable and lets droplets travel farther
• More time spent indoors in crowded, enclosed spaces
• Less sunlight and lower vitamin D levels, which may affect immunity
• Reduced nasal defenses in cold air

Nevertheless, influenza can spread in any season whenever there is crowding, poor ventilation, or close contact with infected people.

Myth #17:  “Natural immunity is better than vaccination.”

Fact: The flu vaccine provides safe, controlled protection that is tailored to the viruses circulating each season. Natural flu infection comes with high risks, and the immunity it creates is not necessarily better.

Myth #18:  “My child has asthma, so he can’t get vaccinated.”

Fact: Asthma is not a contraindication for vaccination. In fact, children with asthma are strongly advised to receive the inactivated flu vaccine because respiratory infections pose higher risks for them. Most asthma triggers, such as dust mites, pollen, pet dander, and mold, are unrelated to vaccines.

Myth #19:  “Pregnancy is not suitable for flu vaccination.”

Fact: A flu shot during pregnancy reduces the risk of severe illness from flu by about 40~50% and provides passive immunity to your baby for the first several months after birth. Inactivated (injectable) flu vaccines are safe and recommended during any trimester.

Pregnant women are among the priority groups recommended for flu vaccination.

 
Myth #20:  “My kid still catches colds after getting vaccinated, so the vaccine is ineffective.”

Fact: Flu vaccine is only for influenza prevention. Children may still catch colds after vaccination, but this does not mean the vaccine doesn’t work. The flu vaccine is important for protecting young children from severe illness, because:

• Their immune systems are still developing.
• Their airways are smaller, so infections can cause serious breathing problems.
• They cannot clearly express their symptoms, which may delay treatment.
• They shed viruses longer (up to two weeks) and can easily infect family members.

 

Myth #21:  “I’m allergic (body type); I can’t get vaccinated.”

Fact: Most people with allergies, such as allergic rhinitis, eczema, asthma, food allergies, or dust mite and pollen allergies, can safely get the flu vaccine. Doctors strongly recommend it because these individuals have a higher risk of serious complications from the flu. 

True allergies to vaccine ingredients are very rare, about 1~2 cases per million doses. People with allergies can get vaccinated at a hospital or clinic and stay for 15~30 minutes for observation. Signs of a severe allergic reaction (anaphylaxis) usually appear within minutes to a few hours after vaccination and may include:

• Difficulty breathing, wheezing, or hoarseness
• Swelling of the lips, face, tongue, or throat
• Hives or widespread rash
• Rapid heartbeat, dizziness, fainting, or feeling faint
• Nausea and vomiting

Myth #22:  “Egg allergy is a contraindication for the flu shot.”

Fact: This is a common but outdated belief. As of 2025, major health authorities state that people with egg allergies, even those who had severe reactions, can safely receive the flu vaccine without special precautions or skin testing. If you are still concerned, you can choose egg‑free options such as cell‑based or recombinant vaccines. Protecting yourself is far more important than worrying about an extremely low risk.