Situation summary in the Americas
Since epidemiological week (EW) 1 to EW 15 of 2017, Brazil, Colombia, Ecuador, Peru, the Plurinational State of Bolivia, and Suriname have reported suspected and confirmed yellow fever cases.
Following is an update on the situation in Brazil.
In Brazil, since the beginning of the outbreak in December 2016 up to 12 April 2017, there were 2,422 cases of yellow fever reported (623 confirmed, 1,128 discarded, and 671 suspected under investigation), including 326 deaths (209 confirmed, 53 discarded, and 64 under investigation). The case fatality rate (CFR) is 34% among confirmed cases.
According to the probable site of infection,the cases were reported in 359 municipalities, while the confirmed cases were distributed among 108 municipalities in 5 states (Espírito Santo,
Minas Gerais, Pará, Rio de Janeiro, and São Paulo).
With regard to the confirmed fatal cases and their probable site of infection, 151 were in Minas Gerais, four in São Paulo, 48 in Espírito Santo, four in Pará, and two in Rio de Janeiro. In descending order, the CFR among confirmed cases by state is 100% in Pará, 80% in São Paulo, 34% in Minas Gerais, 31% in Espírito Santo, and 20% in Rio de Janeiro.
In the state of Minas Gerais, no new suspected cases have been reported since 23 March 2017, and the date of symptoms onset of the last reported case is 14 March 2017.In the state of Espírito Santo, since EW 9 of 2017, a second increase has been observed in the number of cases, the majority of which are being reported from municipalities in the south of the state.
Local and state authorities are intensifying immunization activities in the area and the possibility that additional cases could be detected among susceptible persons in the area is not excluded.
In Rio de Janeiro, an increase in the number of suspected cases was observed between 15 and 25 March; however, no new cases have been reported since 6 April (Figure 1). Of the 10 confirmed cases, 8 had as probable site of infection the municipality of Casimiro de Abreu, one had the municipality of São Fidelis, and the probable site of infection for the case who resided in Porciúncula is still under investigation.Moreover, in the state of Pará, the number of confirmed cases remains unchanged from EW 13 of 2017.
To date, Aedes aegypti has not been reported to have a role in transmission. However, confirmed epizootics in large cities, such as Vitoria in Espírito Santoand Salvador in Bahia,represent a high risk for a change in the transmission cycle.
