In response to a large, ongoing outbreak of yellow fever in multiple states of Brazil, including near large urban areas and popular tourist destinations, CDC is recommending travelers to the country protect themselves from yellow fever by getting the yellow fever vaccine at least 10 days before travel, and taking steps to prevent mosquito bites during their travel.
CDC recommends that people who are unable to get yellow fever vaccine or aren’t recommended to get it should avoid traveling to areas of Brazil where yellow fever vaccination is recommended. Travelers going to areas with ongoing outbreaks may consider getting a booster dose of yellow fever vaccine if it has been 10 or more years since they were vaccinated.
Yellow fever vaccine is available at a limited number of clinics in the United States, so travelers should plan ahead to get the vaccine. For more on yellow fever vaccination clinics: https://wwwnc.cdc.gov/travel/yellow-fever-vaccination-clinics/search.
Brazilian public health authorities announced in early 2017 an outbreak of yellow fever in several eastern states of Brazil, including areas where yellow fever was not traditionally considered to be a risk. Since the end of 2017, yellow fever cases have reoccurred in several states, especially in the states of Rio de Janeiro, Minas Gerais, and São Paulo, including areas close to the city of São Paulo.
In early 2018, a case of yellow fever was reported in an unvaccinated Dutch traveler who had stayed near the São Paulo metropolitan region. Since then, there have been reports of other unvaccinated travelers to Brazil who visited areas with yellow fever outbreaks and contracted yellow fever; many of these travelers were infected on the island of Ilha Grande (Rio de Janeiro State). Four travelers have died in this outbreak.
For more information: https://wwwnc.cdc.gov/travel/notices/alert/yellow-fever-brazil.