The 2026–2027 Flu Vaccine Update in the Philippines: What You Need to Know
First: What does "valent" even mean?
It refers to the number of influenza strains the vaccine protects against. The flu virus isn't a single strain — it mutates constantly and exists in multiple forms simultaneously. Each year, health authorities study which strains are most likely to circulate and update the vaccines accordingly.
So when a vaccine is "trivalent," it protects against 3 strains. "Quadrivalent" means 4.
Trivalent flu vaccine: what it covers
The trivalent influenza vaccine protects against three strains:
Influenza A (H1N1)
Influenza A (H3N2)
One Influenza B virus (Victoria lineage)
It is the current WHO-recommended formulation — and as of May 2025, at least 40 countries worldwide are already using or actively switching to trivalent vaccines.
Quadrivalent flu vaccine: what it covers
The quadrivalent influenza vaccine protects against four strains:
Influenza A (H1N1)
Influenza A (H3N2)
Two Influenza B viruses (Victoria and Yamagata lineages)
A reliable, widely trusted option with an excellent safety profile and a long track record of effectiveness.
What changed — and why
Since September 2023, the WHO influenza vaccine composition advisory committee has determined that including a B/Yamagata lineage antigen in flu vaccines is no longer warranted.
Here's why: B/Yamagata is one of the two Influenza B strains covered by the quadrivalent vaccine. Since March 2020, it has not been detected naturally anywhere in the world. The WHO's Global Influenza Surveillance and Response System — which monitors flu strains continuously across countries worldwide — has found no confirmed cases of naturally occurring B/Yamagata viruses in over five years. This is indicative of a very low risk of infection.
Based on this, the WHO recommends removing B/Yamagata from seasonal influenza vaccines as soon as possible. Including a strain that is no longer circulating adds no protection — so the trivalent formula keeps the vaccine focused on the strains that actually matter.
This is not a downgrade. It is the formula being kept current and accurate.
So which one should you get this season?
Both are good options — and both are available at Vaxcen.
The trivalent is the current WHO-recommended choice. It is updated to protect against the strains genuinely posing a public health risk right now, and it has been adopted by at least 40 countries globally as of May 2025.
The quadrivalent remains a safe, effective, and widely trusted option. Both trivalent and quadrivalent influenza vaccines have excellent safety profiles — the WHO document confirms this directly. If you've been receiving the quadrivalent consistently and feel comfortable continuing, that is a perfectly valid decision.
The most important thing is getting vaccinated — whichever formulation you choose, you're making the right call.
Does it matter for children vs. adults?
Both vaccines are available for pedia and adult use at Vaxcen. The same guidance applies across age groups. Your Vaxcen team will help you choose the right option for your child's age and health history.
What about side effects — are they different between the two?
No meaningful difference. The WHO confirms that both trivalent and quadrivalent influenza vaccines have excellent safety profiles. Common mild reactions — soreness at the injection site, slight fatigue, or a low-grade fever within 24 to 48 hours — are temporary and a normal sign that your immune system is building protection.
Neither vaccine can give you the flu.
How often do you need to get vaccinated?
Every year. The WHO reviews and updates flu vaccine composition annually through its Global Influenza Surveillance and Response System. Annual vaccination ensures your protection reflects the strains most likely to be circulating in the current season.
For the latest vaccine prices, visit the Vaxcen website or message us on Facebook.
Where to get your flu vaccine at Vaxcen
Vaxcen has two branches — both easy to visit on a regular day out:
SM Megamall, Level 5 Mega A EDSA corner Doña Julia Vargas Ave, Ortigas Center, Mandaluyong City, 1555 Metro Manila
Fishermall, 3rd Floor Quezon Ave, Quezon City, 1104 Metro Manila
Ready to get vaccinated? You have two easy ways to book:
Book directly on the Vaxcen website and secure your slot in minutes — or send us a message on Facebook and our team will help you get scheduled.
Walk-ins are also welcome at both branches, subject to vaccine availability. To make sure your preferred vaccine is ready when you arrive, booking ahead is the easiest way to go.
No consultation fee. No complicated process. Just show up and we'll take care of the rest.
Book your flu vaccine at Vaxcen today.