The São Paulo State Department of Health registered another case of yellow fever in the state. The patient is a 55-year-old man with no history of vaccination and who lives in the city of Lagoinha, in the Vale do Paraíba region, which accounts for 82% of cases of the disease this year. As a result, the state of São Paulo already has 11 cases of yellow fever in 2026, with six deaths. Of this total number of registered cases, nine occurred in the Vale do Paraíba region, with five deaths. None of these people who were confirmed to have yellow fever had a history of vaccination. Related news: State of São Paulo confirms fifth death from yellow fever this year. Government of SP reinforces yellow fever vaccine in the ABC region. SP: anyone who received a split yellow fever vaccine must complete the course. Last year, the state confirmed 57 cases of yellow fever, with 35 deaths. Because of this scenario, the São Paulo State Department of Health intensified the alert for vaccination against the disease. Immunization is recommended for the entire population and is available free of charge in Basic Health Units (UBSs) throughout the state. "The vaccine against yellow fever is safe, effective and is available in the Basic Health Units of the 645 municipalities in São Paulo. Since 2019, immunization has been recommended for the entire population of the state. Therefore, the recommendation is that anyone who has not yet been vaccinated should look for a UBS, especially before traveling to forested areas or regions where the virus is circulating", explains Tatiana Lang, director of the Epidemiological Surveillance Center of the State of São Paulo. >> Follow the Agência Brasil channel on WhatsApp Who should get the yellow fever vaccine: Children: one dose at 9 months of age and a booster dose at 4 years of age; People who received only one dose before the age of 5: must take a booster dose; People aged 5 to 59 who have not yet been vaccinated should receive a single dose; People vaccinated with a fractional dose in 2018, during emergency campaigns, should check the need to update their booklet. Yellow fever Yellow fever is an acute febrile infectious disease caused by a virus, transmitted by the bite of a wild mosquito, which lives in forest areas. There is no direct person-to-person transmission.  An indicator of the presence of these transmitting mosquitoes is the death of monkeys, which also suffer from high mortality rates when infected. Therefore, the sighting of dead monkeys must be reported to the municipal health teams. The initial symptoms of yellow fever are fever, chills, severe headache, back pain, body aches, nausea and vomiting, fatigue and weakness. The disease can be prevented through a vaccine, which is available free of charge through the Unified Health System (SUS). Since April 2017, Brazil has adopted a vaccination schedule of just one dose for a lifetime, a measure that is in accordance with the recommendations of the World Health Organization (WHO).