Babies infected with the chikungunya virus during labor and delivery are at high risk of developing serious neurologic problems as newborns, according to a new study.
Between January 1 and December 10, 2025, 18 countries and one territory in the Americas Region reported 313,132 chikungunya cases to PAHO.
A model that tracks the impact of USAID funding cuts estimates that more than 760,000 people have died as a result of those cuts since January 2025.
Through December 10, the world has seen 502,264 chikungunya cases worldwide, with 291,451 in the Americas region alone.
Chikungunya is rarely fatal, but it can cause fever and sometimes severe joint pain.
Uneven distribution of cases makes it difficult to call the situation a global rise, but ongoing transmission and several risk factors boost the potential for further spread, the WHO says.
The company said durable protection from a single dose is highly valuable, especially where vaccine access is limited.
Mississippi has recorded 115 pertussis cases this year, sharply higher than in 2024.
France and Italy continue to battle chikungunya outbreaks and the spread of dengue, as Greece probes possible local malaria cases.
In a chikungunya genotype shift, detection of ECSA in at least 4 countries is concerning, because cocirculation enhances the risk of adaptation.
