Brazil: Yellow fever on Marajó Island, Pará state
During the Carnival holiday, the Ministry of Health arranged for a technical team from the Emergency Operations Center for Dengue and Other Arboviruses (COE) to be sent to Belém, the capital of Pará. The team arrived on Wednesday, March 5 with the mission of supporting the State in investigating cases of yellow fever. Together with professionals from the Pará State Health Department (SESPA) and the Breves Municipal Health Department (SEMSA/Breves), the group is carrying out a diagnosis of the health structure of the municipality of Breves, one of the 17 municipalities and the largest on Marajó Island.
Located 233 kilometers from the capital, Breves is the most populous municipality on the island and has so far recorded five confirmed deaths from the disease. Until the arrival of the technical team, 37 cases of yellow fever had been reported, of which 15 were confirmed, seven are still under investigation, nine were ruled out and six remain as suspects.
“We are here to support the actions of the state and the municipality. We held a meeting to align actions, where data on the local epidemiological scenario were presented. Starting on Thursday, teams from SESPA and the Ministry of Health will produce a situational diagnosis in the municipality of Breves, mapping isolated families, possible primates killed by the disease and developing actions in the areas of assistance, surveillance and risk communication to protect the local population. In Belém, a team will be available to the state to activate a local COE”, explains the general coordinator of the Strategic Information Centers for Health Surveillance (CGCIEVS) and representative of the Dengue COE Command, Daniel Coradi.
Vaccination is the main strategy for preventing yellow fever. In Brazil, the Unified Health System (SUS) provides the vaccine free of charge to the entire population. Since April 2017, the country has adopted a single-dose regimen throughout life, in accordance with the recommendations of the World Health Organization (WHO).
Currently, yellow fever vaccination coverage in Brazil is 72.6%. In the state of Pará, this rate is 54.03%, while in the municipality of Breves it is half the state average. The data are from the National Health Data Network (RNDS) and refer to doses administered up to November 2024.
To reinforce immunization, the Ministry of Health has already sent 442,400 doses to Pará in 2025 alone. This amount corresponds to 75.5% of the total distributed to the state in the previous year. In addition, between March 10 and 21, SESPA, with the support of the ministry, will promote a vaccination campaign against yellow fever in the state.
Yellow fever is an acute infectious febrile disease that can be prevented with a vaccine. It has a rapid progression and variable severity, and can be fatal in its most severe forms. Transmission occurs in two distinct cycles: in the urban cycle, the vector is the Aedes aegypti mosquito ; in the sylvatic cycle, transmission occurs by mosquitoes that are predominantly sylvatic. Non-human primates (NHPs) are considered the main hosts of the virus and, like humans, are also victims of the disease. In the sylvatic cycle, humans are accidentally infected.
Initial symptoms include fever, chills, severe headache, muscle aches, nausea, vomiting, fatigue, and weakness. Most infected individuals recover after this initial phase. However, about 30% of cases progress to severe disease after an asymptomatic period of a few hours to a day, which can lead to death.