Since December 2016, Brazil has experienced an unusually large outbreak of yellow fever (YF). Whether urb a n transmission may contribute to the extent of the outbreak is unclear. The objective of this study was to characterize YF virus (YFV) genomes and to identify spatial patterns to determine thedistribution and origin of YF cases in Minas Gerais, Espírito Santo and Rio de Janeiro, the most affected Brazilian states during the current YFV outbreak.

7th February 2018 • comment

The authors of this study tested nonhuman primates (NHP) sampled during 2012 to 2017 in urban and peri-urban areas severely affected by ZIKV and CHIKV in Brazil. Seroprevalence and antibody titers were low for both viruses. Additionally, they found evidence for infection by heterologous viruses eliciting cross-reactive antibodies. These data suggest that urban or peri-urban NHP are not easily infected by ZIKV and CHIKV despite intense local transmission, and they may also imply that the ZIKV and CHIKV outbreaks in the Americas cannot be sustained in urban or peri-urban NHP once human population immunity limits urban transmission cycles.

31st January 2018 • comment