Evidence is increasing that Zika virus can cause extensive damage to the central nervous system, affecting both fetuses and adults. We sought to identify traces of possible clinical manifestations of nervous system diseases among the registers of hospital admissions recorded in the Brazilian Unified Health System. Time series of several diagnoses from the International Classification of Diseases, 10th Revision, were analyzed by using control diagrams, during January 2008-February 2016. Beginning in mid-2014, we observed an unprecedented and significant rise in the hospitalization rate for congenital malformations of the nervous system, Guillain-Barré syndrome, encephalitis, myelitis, and encephalomyelitis. These conditions are compatible with viral infection and inflammation-associated manifestations and may have been due to the entrance of Zika virus into Brazil. These findings show the necessity of adequately diagnosing and treating suspected cases of Zika virus infection and also that health surveillance systems can be improved by using routine data.
Keywords: Aedes; Brazil; Zika virus; health surveillance; information systems; neuropathies.