Zika virus may cause broader range of brain disorders than previously believed | World news | The Guardian

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ZIKA

> http://www.theguardian.com/world/2016/apr/10/zika-virus-brain-disorders-brazil-study <http://www.theguardian.com/world/2016/apr/10/zika-virus-brain-disorders-brazil-study>
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> Zika virus may cause broader range of brain disorders than previously believed
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> The Zika virus <http://www.theguardian.com/world/zika-virus> may cause a wider range of brain disorders than previously thought, according to a small study released on Sunday. Scientists already suspect the mosquito and sex-spread virus causes fetal brain disorder and temporary paralysis.
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> The study followed patients with symptoms of arboviruses, the family of infectious agents that includes Zika and dengue, who came to a hospital in Recife, Brazil <http://www.theguardian.com/world/brazil>, between December 2014 and June 2015.
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> Six people developed neurological symptoms and two suffered attacks that swelled the brain and damaged its myelin, the fatty material that protects nerves there and at the spinal cord.
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> The research was presented on Sunday at the annual conference for the American Academy of Neurology in Vancouver. Its abstract concluded that “there is strong evidence that this epidemic has different neurological manifestations” than those already documented.
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> All the people arrived in the hospital with a fever, then a rash, and some suffered red eyes, itching and aching muscles and joints – the known symptoms of the Zika virus. The neurological symptoms sometimes began immediately, or as long as 15 days after patients first sought treatment.
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> All six people tested positive for the Zika virus, and negative for dengue fever and chikungunya.
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> After they left hospital, five reported problems with motor functioning; one reported trouble with vision and memory.
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> “Though our study is small, it may provide evidence that in this case the virus has different effects on the brain than those identified in current studies,” said the study’s author, Dr Maria Lucia Brito Ferreira of the Restoration hospital in Recife, Brazil.
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> Brito Ferreira repeated a common refrain of Zika research: the research is early and still inconclusive, and meant to add to the growing investigation to discover what the virus actually does. In all, her team documented 151 cases with neurological symptoms.
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> “This doesn’t mean that all people infected with Zika will experience these brain problems,” Ferreira said. “Of those who have nervous system problems, most do not have brain symptoms.
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> “However, our study may shed light on possible lingering effects the virus may be associated with in the brain.”
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> The brain swelling, called acute disseminated encephalomyelitis (ADEM), resembles multiple sclerosis in some symptoms but is not a permanent condition. ADEM usually consists of a single or occasional attack, from which most people can recover over several months.
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> Four of the people followed for Ferreira’s research developed Guillain-Barré syndrome (GBS), a serious brain condition that enervates muscles, and can leave people temporarily paralyzed and breathing through ventilators.
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> Like ADEM, the condition attacks myelin, and many people also recover from GBS after several months. Earlier this year, scientists published strong evidence <http://www.theguardian.com/world/2016/feb/29/zika-virus-scientists-evidence-guillain-barre-link> that Zika is linked to GBS through a study on 42 cases in French Polynesia.
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> Dr James Sejvar, a neurologist with the US Centers for Disease Control and Prevention, said that cases of ADEM do not appear to afflict people with Zika as often as cases of GBS.
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> “But these findings from Brazil suggest that clinicians should be vigilant,” he said, for signs of ADEM and other central nervous system diseases.
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> “Of course, the remaining question is ‘why,’” Sejvar said. “Why does Zika virus appear to have this strong association with GBS and potentially other immune-inflammatory diseases of the nervous system?”
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> Experts at the World Health Organization also “implicated” Zika in a disorder called microcephaly <http://www.theguardian.com/world/2016/mar/22/who-zika-virus-implicated-in-large-numbers-of-brain-damaged-babies>, which causes babies to suffer brain damage and abnormally small heads. In February, a few days after experts warned that the virus could be a greater threat <http://www.theguardian.com/world/2016/jan/30/zika-virus-health-fears> than Ebola, the organization declared a global public health emergency <http://www.theguardian.com/world/2016/feb/01/zika-virus-world-health-organisation-declares-global-health-emergency>.
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> Scientists have yet to confirm what conditions the virus actually causes, although research has raced to study the once rare pathogen, which emerged from a remote forest in Uganda <http://www.theguardian.com/global-development/2016/feb/13/zika-uganda-world-most-dangerous-viruses-malaria>.
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> That the evidence is still inconclusive has many scientists cautioning the public and leaders not to fuel hysteria <http://www.theguardian.com/world/2016/feb/17/zika-hysteria-health-expert-research-leslie-lobel> around it.