The current yellow fever epidemic in Brazil is the most severe outbreak of the last 5 decades and raises concerns for some local doctors and other countries, some of them not even neighboring the Latin American country.

Locally, the rapid dispersion is concerning because infections are not limited to the jungle or remote rural areas but are also seen in the areas surrounding the most densely populated cities of São Paulo, Minas Gerais, Espiritu Santo, Bahia, and Rio de Janeiro.

Now Brazil is considering the possibility of immunizing the entire population, a decision that is hampered by limitations in the number of doses available.

São Paulo recently made it to the list of risk areas, a decision that affects business travelers. "If you are going to make a connection in São Paulo, you do not need to get vaccinated because the airport has mosquito controls and low temperatures. But if you are going to spend a day in São Paulo, get vaccinated even for one night in a nearby hotel to the Guarulhos airport.

Yellow fever can present with a wide spectrum of manifestations, including asymptomatic, subclinical, nonspecific febrile disease, without jaundice, and the potentially fatal form, with fever, jaundice, renal failure, and haemorrhage.