17 Jun 2015
Yellow fever: Goiás state, BrazilConfirmation of a case of yellow fever in a previously unvaccinated woman living in Alexânia, Goiás state
On 1 June, 2015 the Government of Goiás state, Brazil issued a health alert following confirmation of a case of yellow fever in a previously unvaccinated woman living in Alexânia, Goiás state. The case was diagnosed and treated in Brasilia, Federal District [1, 2].
A public health response is underway; unimmunized residents and visitors to Alexânia are recommended to be vaccinated and surveillance for further cases has been enhanced [1, 2].
To date in 2015 the health authorities in Goiás have reported of total of five cases of yellow fever (three under investigation and two confirmed cases). Three deaths have been reported. The likely areas where infection was acquired were: Alto Paraíso, Niquelândia, São Miguel do Araguaia and Alexânia [1, 2].
Yellow fever in the Americas
Since January 2015, in Brazil confirmed human cases of YF have been reported from the States of Amapá and Goiás ; these are known risk areas for YF transmission.
In South and Central America, 13 countries are considered endemic for YF. These are listed by the World Health Organization (WHO) as countries with risk of YF transmission . Over the last three decades, the majority of cases of YF in the Americas have been reported from Peru (54% of all cases), Bolivia (18%), Brazil (16%), and Colombia (7%) .
In the Americas, the YF virus is usually transmitted in jungle areas via the bite of the Haemagogus spp. mosquito. The biting/feeding time for this mosquito are thought to be both during the day and night. The Aedes aegypti mosquito, also prevalent in the Americas, favours an urban environment and can also transmit YF. Urban areas are at risk of introduction of YF due to human traffic between jungle and urban locations. A. aegypti feeds predominantly during daylight hours.
Advice for travellers
YF is transmitted to humans via the bite of an infected mosquito. You should take mosquito bite avoidance measures day and night.
If you are travelling to or through areas of Brazil with risk of YF, including the states of Amapá or Goiás, vaccination is recommended for your personal protection.
Full details of YF vaccination recommendations can be found on the Country Information pages. Some travellers may require vaccination for certificate purposes. Details of the countries that require proof of YF vaccination as a condition of entry under the International Health Regulations (2005) are also provided.
Advice for health professionals
When undertaking YF risk assessment, health professionals should refer to the individual country information pages where detail relating to risk areas, recommendation for YF vaccination and certificate requirements are available. A map of the current areas where YF vaccine is recommended in the Americas has been produced by the WHO. This provides a useful guide for the consultation, and health professionals are also encouraged to access the Outbreak Surveillance Database, where verified and unverified outbreaks of YF are posted.
Under the International Health Regulations (2005), countries are no longer required to automatically report YF outbreaks to the WHO ; surveillance and reporting of YF in YF risk countries can be poor.