Yellow Fever in a Brazilian Family Returning From Vacation in an Endemic Area: Relevant Clinical Features and Epidemiological Issues

We report three cases of yellow fever (YF) in a family traveling from the city of Sao Paulo, Brazil (without previous vaccination) to an endemic area, acquiring the disease and presenting mild-to-moderate symptoms. Despite posing the intermittent risk of YF in endemic areas, it also alerts to the threat of introduction and spread of YF in the urban cycle, when infected travelers return to non-endemic areas where potential vectors are highly prevalent.