Prevalence and Clinical Attributes of Congenital Microcephaly - New York, 2013-2015

Congenital Zika virus infection can cause microcephaly and other severe fetal neurological anomalies. To inform microcephaly surveillance efforts and assess ascertainment sources, the New York State Department of Health and the New York City Department of Health and Mental Hygiene sought to determine the prevalence of microcephaly in New York during 2013-2015, before known importation of Zika virus infections. Suspected newborn microcephaly diagnoses were identified from reports submitted by birth hospitals in response to a request and queries of a hospital administrative discharge database for newborn microcephaly diagnoses. Diagnoses were classified using microcephaly case definitions developed by CDC and the National Birth Defects Prevention Network (NBDPN). During 2013-2015, 284 newborns in New York met the case definition for severe congenital microcephaly (prevalence = 4.2 per 10,000 live births). A substantial proportion of newborns with severe congenital microcephaly (42%) identified in this analysis did not have any known maternal conditions or maternal/fetal exposures documented in the newborn hospital record.