The Scientific Study Group for Travel Medicine advises all travelers to Brazil to be vaccinated against yellow fever, regardless of the region they visit. Travelers who go to Rio de Janeiro or Sao Paolo for carnival must also be vaccinated.
Yellow fever is a viral condition that is transmitted by mosquitoes. In January 2018, new cases of yellow fever were reported in Brazil, even in areas that were previously known as a non-risk zone. In Brazil, a general national vaccination campaign is in progress.
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A yellow fever vaccination should in principle be administered ten days before departure. Even if you are late, the vaccination can be useful during longer holidays. If you are not yet protected by the vaccination, be sure to apply mosquito-repellent measures to minimize the risk. If travelers are younger than 9 months or older than 60, the doctor must weigh the pros and cons of vaccination.