Background Chikungunya virus (CHIKV) emerged in the Americas in 2013 and has caused ~2.1 million cases and over 600 deaths. A retrospective investigation was undertaken to describe clinical, epidemiological and virus genomic features associated with deaths caused by CHIKV in Ceará state, northeast Brazil. Methods Sera, cerebrospinal fluid (CSF) and tissue samples from 100 fatal cases with suspected arbovirus infection were tested for CHIKV, dengue (DENV) and Zika virus (ZIKV). Clinical, epidemiological and death reports were obtained for patients with confirmed CHIKV infection. Logistic regression analysis was undertaken to identify independent factors associated with risk of death during CHIKV infection. Phylogenetic analysis was conducted using whole genomes from a subset of cases. Results 68 fatal cases had CHIKV infection confirmed by RT-qPCR (52.9%), viral antigen (41.1%), and/or specific-IgM (63.2%). Co-detection of CHIKV with DENV were found in 22% of fatal cases, ZIKV in 2.9%, and DENV and ZIKV in 1.5%. A total of 39 CHIKV-deaths presented with neurological signs and symptoms, and CHIKV-RNA was found in the CSF of 92.3% of these patients. Fatal outcomes were associated with irreversible multiple organ dysfunction syndrome. Patients with diabetes appear to die at a higher frequency during the sub-acute phase. Genetic analysis showed circulation of two CHIKV-East Central South African (ECSA) lineages in Ceará and revealed no unique virus genomic mutation associated with fatal outcome. Conclusion The investigation of the largest cross-sectional cohort of CHIKV-deaths to date reveals that CHIKV-ECSA strains can cause death in individuals from both risk and non-risk groups, including young adults.

Introduction: Chikungunya causes fever and severe and persistent joint pain. Methods: We reported a chikungunya outbreak that occurred in Ceará State, Brazil between 2016 and 2017 with emphasis on epidemiological characterization of cases, high number of deaths, mortality-associated factors, and spatial and temporal spread of the epidemic among municipalities. Results: In November 2015, the first autochthonous cases of chikungunya were confirmed in Ceará, Brazil. In 2016-2017, 195,993 cases were reported, with an incidence of 2,186.5/100,000 inhabitants and 244 confirmed deaths. Conclusions: Rapid transmission and high mortality rate are serious problems, especially in regions with co-circulating arboviruses.

BackgroundChikungunya virus infection in neonates is relatively rare and can lead to death.Case presentationWe report the occurrence of the first death of a mother and child after probable vertical transmission of chikungunya virus in Brazil. A 28-year-old pregnant woman with hypertension presented with symptoms compatible with an arboviral disease at 34 weeks’ gestation. She developed preeclampsia with severe respiratory failure which resulted in the emergency cesarean section, and the patient died 12 days after the onset of symptoms. The pre-term newborn weighed 2535 g, with an Apgar score of 4/8. He was referred to the neonatal ICU with neutrophilia and thrombocytopenia, several seizure episodes, and hemorrhagic disorders, which resulted in death. Chikungunya IgM antibody was detected in the cerebrospinal fluid.ConclusionsWe present the first documented maternal and neonatal death in Brazil after probable chikungunya infection during pregnancy.

Introduction: Newborn who had Zika vírus but did not show microcephaly at birth may have neuropsychomotor development problems. We aimed to evaluate the developmental and anthropometric milestones of asymptomatic children whose mothers had Zika during pregnancy in Northeastern Brazil in 2015 and 2016. Methods: We conducted a descriptive cross-sectional case series study of children in Fortaleza born without microcephaly whose mothers had Zika during pregnancy. Home visits were undertaken to evaluate the developmental milestones and gather anthropometric data of the children and to conduct semi-structured interviews with the mothers to identify their socioeconomic and gestational profiles and assess the newborns after birth. Results: In total, 30 cases were identified. Of these, 17 children and their mothers participated in the study. The median age of the mothers at the time of delivery was 26 years. All were symptomatic, and TORCH was negative. At the time of the home visit, all had growth profiles suitable for their age. However, nearly all children (15/17, 88.2%) presented at least one developmental delay, considering their age group. Conclusions: There were late changes in the neuropsychomotor development of children born to mothers who had Zika during pregnancy, suggesting the need for specialized medical follow-ups.