The recent increase in measles cases in different regions of the world has reignited an important alert: diseases considered controlled can circulate again when vaccination coverage decreases. In a global scenario marked by frequent international travel, declining vaccine adherence in some countries, and the spread of misinformation, immunization has returned to the center of public health discussions.

More than just a topic restricted to measles, this debate reinforces an essential reality: vaccines continue to be one of the most effective strategies to prevent outbreaks, hospitalizations, and deaths from infectious diseases.

According to the Ministry of Health, Brazil maintains active surveillance against the risk of measles reintroduction, especially in light of the virus's circulation in other countries and the international flow of travelers.

What is measles?

Measles is a highly contagious viral disease transmitted primarily through respiratory droplets released when coughing, sneezing, speaking, or breathing. The transmission capacity is so high that a single infected person can transmit the virus to several others even before symptoms appear.

The most common signs include:

  • High fever

  • Persistent cough

  • Runny nose

  • Conjunctivitis

  • Red spots on the body, usually starting on the face and spreading progressively

Symptoms typically appear between 7 and 14 days after contact with the virus.

What are the complications of measles?

Although many people associate measles only with skin spots, the disease can cause serious complications, especially in young children, elderly people, pregnant women, and immunocompromised individuals.

Among the main complications are:

  • Pneumonia

  • Otitis

  • Severe dehydration

  • Encephalitis

  • Neurological involvement

  • Hospital admission

  • Death in more severe cases

Additionally, measles can cause a temporary reduction in the body's immune memory, leaving the person more vulnerable to other infections in the following months.

Why is vaccination so important?

The measles vaccine does not only protect the vaccinated individual. It also reduces the circulation of the virus in the community, protecting more vulnerable people who cannot receive certain vaccines, such as some immunocompromised individuals and pregnant women.

This concept is known as collective protection.

When vaccination coverage falls, the virus finds room to circulate again. This is exactly what happened in various countries in recent years, including regions that had previously controlled the disease.

Mass vaccination transformed diseases that previously caused thousands of deaths into rare events. The impact is not limited to measles. Other potentially serious diseases also depend directly on maintaining vaccination coverage, such as:

  • Pertussis

  • Bacterial meningitis

  • Poliomyelitis

  • Rubella

  • Yellow fever

  • Influenza

  • HPV

  • COVID-19 in priority groups

What changed in the vaccination calendar in 2026?

The National Vaccination Calendar underwent important updates in 2026, reinforcing strategies for population protection and epidemiological surveillance.

Among the most relevant points related to measles are:

  • Reinforcement of guidance on the trivalent viral vaccine

  • Expanded strategies for vaccination blockade in areas with suspected cases

  • Update of recommendations for international travelers

  • Specific guidance for use of the so-called "zero dose" in children between 6 and 11 months in situations of epidemiological risk

Currently, the recommended vaccination schedule includes:

Children

  • 12 months: first dose of trivalent viral vaccine

  • 15 months: second dose

People aged 1 to 29 years

  • Should have two proven doses of the vaccine

People aged 30 to 59 years

  • Should have at least one registered dose

Healthcare professionals

  • Need to prove two doses regardless of age

What if the vaccination card is outdated?

One of the main current difficulties is that many adults do not know if they received all recommended vaccines in childhood.

In these cases, the guidance from the Ministry of Health is to seek a health facility for assessment of vaccination status. In many situations, it is possible to update the schedule safely.

Vaccination continues to be offered free of charge by the SUS (Unified Health System).

Beyond vaccination: how to prevent measles?

Although vaccination is the primary form of prevention, other measures help reduce the risk of transmission:

  • Frequent hand hygiene

  • Respiratory etiquette

  • Isolation of suspected cases

  • Early medical care when symptoms appear

  • Active epidemiological surveillance

  • Update vaccination card before international travel

Vaccinating is an individual decision with collective impact

In public health, some choices go beyond the personal sphere. Vaccination is one of them.

When a population maintains high immunization rates, outbreaks become less likely, hospitalizations decrease, and vulnerable people become more protected. When this coverage falls, diseases previously controlled can return quickly.

The history of medicine has shown many times that prevention is more efficient and less painful than dealing with the consequences of preventable epidemics.

This content is exclusively educational and informative in nature. It does not replace medical evaluation, diagnosis, or consultation with a healthcare professional. If you have questions about vaccination or symptoms, seek medical care or visit a health facility.

Dr. Rebeca Soares Andrade CRM-GO 39335