Flu Vaccine 2026 for Children in Brazil: Complete Guide for Expat Families
Dra. Paula Andrade
CRM-SP 204778 | RQE 131771 | Título SBP 2024
Licensed in Brazil — Itaim Bibi, São Paulo
Brazil's Ministry of Health ran the 2026 National Flu Vaccination Campaign from March 28 to May 30 in the Northeast, Center-West, South, and Southeast regions, but the vaccine remains available year-round at public health clinics (UBS) because it is part of the National Vaccination Calendar. Many expat parents still have questions: Does my child need it? From what age? What is the difference between the public (SUS) and private clinic vaccines? In this guide, I explain everything about the 2026 flu vaccine for children in Brazil — what changed in the strains, who should get vaccinated, side effects, and how to protect your child this winter.
Quick Summary
Who should get it: All children from 6 months to under 6 years (priority group in public healthcare/SUS).
When: National campaign ran March 28 – May 30, 2026 at UBS; the vaccine is available year-round through SUS.
Updated strains: Three strains updated by Anvisa for 2026 (H1N1, H3N2, and B/Victoria).
SUS vs Private: SUS offers the free trivalent vaccine. Private clinics have the quadrivalent.
What Changed in the 2026 Flu Vaccine?
The influenza virus constantly mutates and can cause serious complications such as pneumonia, ear infections, and sinusitis — which is why the vaccine is reformulated every year. For 2026, Anvisa (Brazil's FDA equivalent) defined three updated strains based on viruses circulating in the Southern Hemisphere:
2026 Trivalent Vaccine Composition
- 1.A/Missouri/11/2025 (H1N1)pdm09 — updated strain
- 2.A/Singapore/GP20238/2024 (H3N2) — updated strain
- 3.B/Austria/1359417/2021 (Victoria lineage)
The quadrivalent vaccine (available at private clinics) also includes an additional B strain from the Yamagata lineage.
The changing strains are exactly why annual vaccination is necessary. Last year's vaccine does not protect against the 2026 variants. Even if your child received the vaccine in 2025, they still need the 2026 dose.
Who Should Get the Flu Vaccine?
The Brazilian Pediatric Society (SBP) and the Ministry of Health recommend vaccination for all children from 6 months of age. In the public health system (SUS), the priority groups include:
Priority Groups in SUS (Public Healthcare)
- Children 6 months to under 6 years
- Pregnant and postpartum women (up to 45 days)
- Adults over 60
- People with chronic conditions ( asthma, diabetes, heart disease)
- Healthcare and education professionals
Children who attend daycare or school should be vaccinated as soon as possible, as they are more exposed. Starting in 2025, the flu vaccine became part of the National Vaccination Calendar, available at public health clinics year-round — not just during the campaign. This is great news for families who miss the campaign period.
Need help navigating Brazil's vaccination system?
Dr. Paula guides expat families through the vaccination schedule, combining SUS and private options.
Book a ConsultationHow Many Doses Does My Child Need?
Dosing Schedule
First time getting vaccinated (6 months to 9 years)
2 doses, 30 days apart
Already vaccinated in previous years
1 annual dose (booster with updated strains)
Over 9 years old
1 annual dose, regardless of history
Important: Babies under 6 months cannot get the flu vaccine. Their protection depends on the mother's vaccination during pregnancy and breastfeeding, which transfers antibodies.
SUS or Private Clinic: Which One to Choose?
| SUS (Free) | Private Clinic | |
|---|---|---|
| Type | Trivalent (3 strains) | Quadrivalent (4 strains) |
| Extra Protection | — | + 1 B strain (Yamagata) |
| Cost | Free | R$100-180 per dose (~US$18-32) |
| Efficacy | High | High (+ B coverage) |
My recommendation: Both are excellent options. If your family can afford it, the quadrivalent vaccine offers slightly broader protection. But the SUS vaccine is safe, effective, and covers the three most important strains. The most important thing is to vaccinate — regardless of which one you choose. For expat families, private clinics often offer a more comfortable experience with English-speaking staff. Learn more about healthcare costs in Sao Paulo.
This is the same reasoning I explained in the guide about the complete 2026 vaccination calendar: the best vaccine is the one your child actually receives.
Side Effects: What to Expect
The inactivated flu vaccine (injection) is very safe. The most common side effects are mild and temporary:
Common Reactions (normal, not a cause for concern)
- •Pain and redness at the injection site (up to 2 days)
- •Low-grade fever (up to 38°C/100.4°F) in the first 24-48 hours
- •Irritability and mild fatigue on vaccination day
- •Headache and muscle aches in older children
These symptoms do not mean your child caught the flu. It is simply the immune system responding to the vaccine — exactly what we want to happen. If the fever exceeds 38.5°C (101.3°F) or lasts more than 48 hours, contact your pediatrician.
Common Myths About the Flu Vaccine
“The flu vaccine gives you the flu.”
False. The injected vaccine contains inactivated (dead) viruses. It is impossible to catch the flu from the vaccine. Mild symptoms like low-grade fever are normal immune responses, not the flu.
“My child is healthy, they do not need the vaccine.”
False. Healthy children can also develop serious complications from the flu, including pneumonia and ear infections. The flu is very different from a common cold — it can be a serious illness in young children.
“My child got it last year, they do not need it again.”
False. The virus changes every year, and the vaccine is reformulated accordingly. The 2025 dose does not protect against the 2026 strains. Annual vaccination is essential.
Vaccination is part of routine pediatric checkups. At each visit, we review the vaccination calendar and provide guidance on upcoming doses. Also check our guide on preparing for back to school, which includes all the vaccines needed for the school environment. If you are concerned about dengue in children, that is another important vaccine to discuss with your pediatrician.
Frequently Asked Questions
At what age can my baby get the flu vaccine in Brazil?
What is the difference between the SUS (public) and private flu vaccine?
Can the flu vaccine give my child the flu?
Can my child get the flu vaccine if they have a cold?
When was the 2026 flu vaccination campaign in Brazil?
Does my child need the flu vaccine every year?
Questions About Your Child's Vaccination?
Schedule a consultation for personalized guidance on your child's complete vaccination schedule in Brazil.
Consultório no Itaim Bibi, São Paulo | CRM-SP 204778 | RQE 131771
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