The state of São Paulo reached 40 confirmed cases of measles in 2026, with children under the age of two accounting for approximately 60% of the infections, according to data released by the State Health Secretariat and reported by Agência Brasil. Health authorities note that 30 of the 40 infected individuals lacked proper vaccination records, while ongoing transmission chains continue to be actively monitored across the region. During the entire year of 2025, the state recorded two cases of measles, and no deaths have been reported among the 40 confirmed cases this year. Up to now, authorities have discarded more than 1,700 suspected measles notifications across the state.
Measles Cases Concentrated in São Paulo Capital
The capital city concentrates the vast majority of the state’s total burden, accounting for 36 of the 40 confirmed infections. Additional cases include two patients in São Bernardo do Campo, one in Santo André, and one in Guarulhos. Three recent diagnoses in the capital involved two men, aged 18 and 21, and a one-year-old baby. Epidemiological tracking shows these latest infections tie directly to transmission chains that have been under observation since June. Surveillance actions include contact tracing, laboratory analysis by the Adolfo Lutz Institute, and, for confirmed cases, genetic sequencing of the virus with support from Fiocruz. The first transmission chain identified in 2026, occurring between March and April and linked to two imported cases, was closed after 12 weeks passed without any related occurrences, whereas chains identified in June, July, and August remain under observation by health authorities.
Despite the geographic concentration, health monitors observe an overall trend of reduced transmission. Surveillance teams in Guarulhos and São Bernardo do Campo are evaluating criteria to officially close transmission chains associated with earlier local cases. Protocol dictates that a transmission chain closes when no related cases appear within a 90-day window, or 12 weeks, measured from the onset of the rash in the last confirmed patient. During this interval, teams continue investigating suspected notifications and conducting active searches.
Vaccination Gaps Drive Susceptibility Among Infants
Unvaccinated individuals or those with incomplete immunization schedules represent 75% of the total caseload, totaling 30 out of the 40 confirmed patients. Among the three newest patients identified by the State Health Secretariat, the 21-year-old man and the one-year-old infant had received a single dose of the vaccine, whereas the 18-year-old man had no immunization record on file. Infants under two years old remain the most vulnerable demographic, experiencing the highest proportion of the state’s infections.
Statewide immunization coverage has shown improvement over the course of the year. Data from the state health department indicates that coverage for the first dose of the measles vaccine rose from 86.56% in April to 93.24% in July. Second-dose coverage climbed from 72.72% to 78.37% over the same period, trailing the Ministry of Health target of 95%. During a September multi-vaccination campaign, officials administered more than 2.5 million measles doses across São Paulo, figures that await full integration into official coverage statistics.
Brazil retains its status of eliminated endemic measles transmission, though sporadic cases have appeared in 2026 across São Paulo, Amazonas, and Rio de Janeiro. Concurrently, regional health agencies outside São Paulo face distinct challenges. In Ceará, state immunization coordinators highlight the ongoing risk posed by international and domestic tourism against a backdrop where second-dose coverage reached only 84.78%, failing to meet the national 95% target required for herd immunity. Ceará recorded 96.45% coverage for the first dose among one-year-old children in 2026, investigated a suspected measles case in March that was not detailed by Sesa at the time, and currently has no active suspected cases under investigation while maintaining permanent epidemiological surveillance.
Free Immunization Guidelines Across São Paulo Clinics
The measles vaccine remains available free of charge at public health clinics across all 645 municipalities in São Paulo through the Unified Health System (SUS). The standard immunization protocol requires the first dose of the triple viral vaccine—protecting against measles, mumps, and rubella—at 12 months, followed by the tetraviral vaccine at 15 months, which adds protection against varicella. Healthcare workers must verify two doses regardless of age.
A specialized “zero dose” is currently recommended for infants aged six months to 11 months and 29 days residing in São Paulo, Guarulhos, São Bernardo do Campo, and Santo André. This localized measure serves as an extra precaution during active transmission periods and does not replace the standard doses scheduled at 12 and 15 months. The zero dose can also be indicated for infants in this age group who have had contact with suspected or confirmed measles cases, following evaluation by surveillance teams.
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