RESUMO
BACKGROUND: Large-scale epidemics in countries with high birth rates can create a concerning scenario where pregnant people are more likely to transmit the virus. Additionally, increased international mobility has made arboviruses a growing problem for travelers. The increased risk of vertical transmission has been related to maternal viremia near delivery. Such transmission leads to severe infection of newborns and may be associated with subsequent neurological impairment including cerebral palsy. This case series provides an overview of clinical and laboratory findings in pregnant individuals with confirmed CHIKV infection as well as the clinical effects on their newborn emphasizing the severity of neonatal chikungunya. METHODS: an ambispective case series enrolled newborns with confirmed exposure to CHIKV in utero or in the neonatal period. RESULTS: during the delivery period, the transmission rate among viremic individuals was approximately 62% (18/29). Fever, irritability, rash, and poor feeding in the first week of life were critical signs of neonatal chikungunya, highlighting its severity. CONCLUSION: Close monitoring of healthy newborns during the first week of life is essential in areas affected by CHIKV epidemics, and in offspring of pregnant travelers who visited the outbreaks zones. This case series is intended to increase neonatologists' awareness of the possibility of mother-to-child transmission of CHIKV among newborns with a sepsis-like presentation. Prioritizing CHIKV vaccination for women of childbearing age should also be considered.