This is what TIMATIC says:
/ 15NOV07 / 2223 UTC
National U.S.A. (US) /Embarkation U.S.A. (US)
Destination BRAZIL (BR) /Visited COLOMBIA (CO)
[Health Information]
BRAZIL (BR)
SEE TIRULES/R3 FOR ADDITIONAL PROPHYLACTIC MEASURES.
COLOMBIA (CO) Yellow Fever Infected Areas
Yellow Fever vaccination required if arriving within 10 days
from a Yellow Fever infected country.
Exempt are children under 9 months, expectant mothers and
those holding proof of medical contraindication.
Authorities require that passengers are vaccinated at least
10 days before embarking to Brazil. Certificates issued less
than 10 days before embarkation will not be accepted.
Non-compliance with the health regulations will result in
return to point of origin at carrier's expense.
Nationals of Brazil (irrespective of country of residence)
and those residing permanently in Brazil are also subject to
proof of vaccination if coming from a Yellow Fever infected
country.
Carriers will be fined if not complying with the regulations
of the health authorities.
Malaria prophylaxis recommended.
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PLEASE NOTE! When making health entries for Brazil, Brazil
requires the "last visited countries" to be within 10 days and
not the standard practice of 6 days.
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