What are the symptoms of dengue in children?

Key symptoms include sudden high fever (39-40C), intense headache, pain behind the eyes, body and joint aches, red spots on the skin, nausea, and vomiting. In young children, irritability and excessive crying may be the only signs.

Can children get the dengue vaccine in Brazil?

The Qdenga vaccine is available for children aged 4 and older in Brazil, both through the public health system (SUS) and private clinics. The new single-dose Butantan-DV vaccine is approved for ages 12-59, with studies underway for children 2-11.

When should I take my child to the doctor if I suspect dengue?

Seek IMMEDIATE medical attention if your child is under 2 years old, has intense abdominal pain, persistent vomiting, any bleeding (nose, gums), excessive sleepiness, cold extremities, or worsens after the fever drops (a sign of the critical phase).

Can I give ibuprofen to a child with dengue?

NO. Ibuprofen and other anti-inflammatory drugs (such as aspirin and diclofenac) increase the risk of bleeding in dengue. Use ONLY acetaminophen (paracetamol/Tylenol) for fever and pain. This is the recommendation of the Brazilian Pediatric Society.

How long does dengue last in children?

Dengue typically lasts 7 to 10 days. Fever usually persists for 2-7 days. The most dangerous period is between days 3 and 7, when the fever may drop but the critical phase begins. Full recovery may take 2-4 weeks.

Dengue in Children 2026: Symptoms, Vaccine, and When to See a Pediatrician

In 2026, Brazil is facing a new wave of dengue with a projected 1.8 million cases, with 54% concentrated in Sao Paulo. Children are especially vulnerable to severe forms of the disease. As an expat family living in Brazil, understanding dengue is essential for keeping your child safe. In this guide, I explain how to recognize symptoms, when the situation is an emergency, and everything about the available vaccines — including the new single-dose Butantan-DV.

What Is Dengue and Why Are Children More Vulnerable

Dengue is a viral disease transmitted by the Aedes aegypti mosquito, the same mosquito that transmits Zika and Chikungunya. There are 4 serotypes of the virus (DENV-1, DENV-2, DENV-3, and DENV-4), and a person can get dengue up to 4 times in their lifetime. It is important to distinguish dengue from other common childhood infections, such as the flu and common cold. For expat families new to Brazil, dengue is a tropical disease you may not have encountered before — understanding it is critical.

Why are children a high-risk group?

Less specific symptoms: Babies and young children may only show irritability and fever, making diagnosis difficult
Rapid dehydration: Children lose fluids more quickly than adults
Second infection: Children who have already had dengue once have a higher risk of severe forms upon reinfection
Cannot protect themselves: They depend on adults for prevention (repellent, clothing, screens)

Dengue Symptoms in Children

Symptoms can vary depending on the child's age:

Babies and Toddlers (Under 2 Years)

• High fever without apparent cause
• Intense irritability
• Excessive and inconsolable crying
• Feeding refusal
• Unusual sleepiness or agitation
• Red spots on the skin
• Vomiting

Older Children (Over 2 Years)

• Sudden high fever (39-40°C / 102-104°F)
• Intense headache
• Pain behind the eyes
• Muscle and joint pain
• Red spots across the body
• Nausea and vomiting
• Weakness and fatigue

Pediatrician's Tip

The famous "bone pain" that adults describe is less common in young children. In babies, the main sign may be just irritability — different from their usual behavior. Trust your parental instinct! If something feels off, contact your pediatrician.

The 3 Phases of Dengue: Why a Dropping Fever Can Be Dangerous

Many parents relax when the fever drops. This is the biggest mistake! Dengue has 3 phases, and the most dangerous one is precisely when the fever disappears:

Phase 1: Febrile (Days 1-3)

High fever (39-40°C / 102-104°F), body aches, skin rash, nausea.

During this phase: Intense hydration + acetaminophen. Avoid anti-inflammatory drugs.

Phase 2: Critical (Days 3-7) — THE MOST DANGEROUS

The fever drops, but the child may worsen rapidly. During this phase, complications can occur:

• Plasma leakage (fluid escapes from blood vessels)
• Bleeding
• Shock (blood pressure drops)
• Organ damage

WARNING: If the fever drops and the child becomes more listless, drowsy, or develops abdominal pain — SEEK IMMEDIATE MEDICAL CARE.

Phase 3: Recovery (After Day 7)

Gradual improvement. Intense itching across the body may appear (a sign of recovery).

Maintain adequate hydration and nutrition. Weakness may last 2-4 weeks.

Worried your child may have dengue?

Dr. Paula provides same-day or next-day evaluations. Do not wait for warning signs.

Talk to the Pediatrician

Warning Signs: When to Seek IMMEDIATE Medical Care

Go to the Emergency Room NOW if there is:

Intense and continuous abdominal pain
May indicate internal bleeding
Persistent vomiting (3 or more in 1 hour)
Leads to rapid dehydration
Any bleeding
Nosebleeds, bleeding gums, blood in vomit, stool, or urine
Excessive drowsiness or extreme irritability
Altered level of consciousness
Cold and pale extremities
Cold hands and feet, excessive sweating — signs of shock
Difficulty breathing
May indicate fluid accumulation in the lungs. Learn more about childhood pneumonia
Child under 2 years with any suspicion
At this age, the disease can progress more rapidly
Fever dropped BUT child got worse
Classic sign of entering the critical phase

Dengue Vaccines in 2026: What Parents Need to Know

There are currently 3 dengue vaccines in Brazil. Here is which one is indicated for your child:

Vaccine	Age Range	Doses	Availability
Qdenga (Takeda)	4 to 60 years	2 doses (3 months apart)	SUS + Private
Butantan-DV (new!)	12 to 59 years*	Single dose	SUS (Jan/2026)
Dengvaxia (Sanofi)	6 to 45 years**	3 doses	Private (restricted)

* Studies are ongoing to include children aged 2-11 for the Butantan-DV vaccine
** Dengvaxia is only indicated for those who HAVE already had dengue (risk for seronegative patients)

Pediatrician's Recommendation

For children aged 4 and older, the Qdenga vaccine is available and recommended by the Brazilian Immunization Society (SBIm). Talk to your pediatrician about the best time to vaccinate — ideally before the peak transmission season (summer/fall in Brazil, which is December through May). Also check our 2026 vaccination schedule to keep all immunizations up to date.

Home Care: Treatment and Hydration

There is no specific treatment for dengue. Care focuses on relieving symptoms and preventing complications:

Recommended Care

INTENSIVE HYDRATION
Water, coconut water, oral rehydration solution, natural juices. Offer every 30 minutes. This is the most important step!
Acetaminophen for fever
At the correct dose for weight. Do NOT use ibuprofen, aspirin, or other NSAIDs.
Rest
Light activities only. Avoid exercise until full recovery.
Light diet
Soups, fruits, easily digestible foods. Do not force eating.
Monitor warning signs
Especially between days 3-7. Keep a log of temperature and symptoms.

Prevention: How to Protect Your Child

While vaccines still have age limitations, prevention is essential — especially for expat families who may be unfamiliar with mosquito-borne disease prevention:

At Home

• Eliminate standing water (plant saucers, tires, gutters)
• Install window screens
• Use electric mosquito repellent in the bedroom
• Keep water tanks covered
• Clean pet water bowls frequently

For Your Child

• Age-appropriate repellent:
- - Babies under 6 months: NO repellent (use clothes and screens)
- - 6 months to 2 years: IR3535 or Icaridin
- - Over 2 years: DEET up to 30%
• Long-sleeved, light-colored clothing
• Mosquito net over crib/bed
• Avoid peak hours (dawn and dusk)

To keep your child healthy year-round, also check our guides on the 2026 flu vaccine for children, your first pediatric appointment, and the first-year checkup schedule. If your child is returning to school in 2026, dengue prevention should be part of your preparation checklist.

Scientific References

• Brazilian Ministry of Health. Dengue: Clinical Diagnosis and Management. 2025 Update.
• Brazilian Pediatric Society. Scientific Document: Fever Management in Arboviruses. 2025.
• Instituto Butantan. Butantan-DV Vaccine: Phase 3 Results. 2025.
• Brazilian Immunization Society. Vaccination Calendar 2026.
• World Health Organization. Dengue Guidelines for Diagnosis, Treatment and Prevention. 2024.

Last updated: January 23, 2026