Zika-linked brain disorder in adults identified by Brazilian scientists

Zika has already been linked with the autoimmune disorderGuillain-Barrsyndrome, which attacks peripheral nerves outsidethe brain and spinal cord, causing temporary paralysis that canin some cases require patients to rely on respirators forbreathing.

The findings add to the growing list of neurological damageassociated with Zika.

Brazil said it has confirmed more than 940 cases to berelated to Zika infections in the mothers. Brazil isinvestigating nearly 4,300 additional suspected cases ofmicrocephaly.

"Though our study is small, it may provide evidence that inthis case, the virus has different effects on the brain thanthose identified in current studies," Dr. Maria Lucia Brito, aneurologist at Restoration Hospital in Recife, Brazil, said in astatement.

Brito presented her findings on Sunday at the AmericanAcademy of Neurology meeting in Vancouver. Research presented at meetings should be viewed as preliminary until published in a peer-reviewed medical journal.

The study involved 151 patients who visited her hospital between December 2014 andJune 2015. All had been infected with arboviruses, the family ofviruses that includes Zika, dengue and chikungunya.

All six patients tested positive for Zika, and all hadlingering effects after being discharged from the hospital, withfive patients reporting motor dysfunction, one with visionproblems, and one with cognitive decline.

Why does Zikavirus appear to be strongly associated with disease of nervous system?

Dr. James Sejvar, a neuroepidemiologist for the U.S. Centersfor Disease Control and Prevention, said the ADEM cases linkedwith Zika do not appear to be occurring at the same acceleratedrate as cases of Guillain-Barr, but said doctors should be onthe lookout for ADEM and other central nervous system illnesses.

Sejvar, who has studied Guillain-BarrSyndrome (GBS) inBrazil and is involved in a major clinical trial ofGuillain-Barrin Puerto Rico, said he hopes future studies willshed more light on such questions.

InGuillain-Barr, the immune system attacks the nervous system, resulting in muscle weakness and sometimes paralysis, according to the U.S.Centersfor Disease Control and Prevention.

Zika, which is prevalent in Latin America and the Caribbean, is mainly transmitted through the bite of infectedAedesaegyptimosquitoes. Most healthy people infected with the virus experience no symptoms, but babies whose mothers were exposed to the virus in pregnancy appear to be at special risk formicrocephaly.