The French Indian Ocean island Mayotte was hit by an outbreak of chikungunya in January 2005. The purpose of this retrospective study is to report data recorded over a five-month period (February - June 2006) in the pediatric-neonatal department of the Hospital Center in Mayotte. The study cohort includes a total of 50 children in whom chikungunya was confirmed by molecular tools. Mean age was 9.3 years and the male-to-female sex ratio was 1:5. The main symptoms were intense pain (88%), high fever (82%), and skin rash (80%) that was less common in children under 2 years of age. Neurological complications were observed in 46% of patients including hypotonia (22%) that occurred mainly in newborns, meningitis syndrome (18%) and convulsions (16%) that occurred mainly in children over 2 years of age. Infectious complications included pneumonia (4%), pyelonephritis (2%), and possible nosocomial septicemia due to Pseudomonas (6%). The main hematological abnormalities were lymphopenia (27%) and thrombopenia (16%). Serum CRP values were moderately high (mean, 25 mg/l). Elevated AST (24%) and ALT (10%) values were observed. High CSF protein levels were noted in 30% of cases. A total of 25 children required hospitalization for more than 10 days. There were two deaths in newborns infected before the seventh day of life. The main risk factors for hospitalization longer than 10 days were premature birth and age at the time of chikungunya infection.