New evidence provides a strong link between Zika virus and the birth defect microcephaly.
The virus has been found in tissue samples from two babies with microcephaly who died within 20 hours of their birth along with two miscarried fetuses (11 and 13 weeks), the Center’s for Disease Control and Prevention (CDC) reported Wednesday.
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All four mothers had signs of Zika virus during the first trimester of pregnancy. The samples were all from the state of Rio Grande do Norte in Brazil.
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The South American country has been grappling with a rapid outbreak of Zika virus, which has been blamed for a spike in cases of microcephaly.
Brazilian officials first warned women against getting pregnant in December; additional countries have since followed suit.
Microcephaly is a rare neurological condition in which a baby’s head is significantly smaller than that of other children of the same age and size, usually the result of the brain developing abnormally in the womb or not growing at the normal rate after birth.
This can lead to developmental issues needing speech and other therapies. There is no cure.
A case report also released Wednesday by the New England Journal of Medicine details a European woman who had spent time volunteering in Rio Grande do Norte. In February of 2015 while in Brazil she became pregnant, and at 13 weeks had an illness suspected to be Zika virus.
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She returned to Europe when she was 28 weeks pregnant; testing began to suggest fetal anomalies.
“The clinical presentation raised suspicion of fetal viral infection. Because of severe brain disease and microcephaly, the fetus was given a poor prognosis for neonatal health,” the report states.
A medical termination of the pregnancy was performed at 32 weeks, and the fetus at delivery showed “prominent microcephaly.”
Tissue from the fetus tested positive for Zika virus.
Last week after the World Health Organization declared Zika virus an international public health emergency. It mosquito-borne and related to dengue fever, West Nile and Japanese encephalitis viruses, according to the European Centre for Disease Prevention and Control.
Zika virus has also been found to be transmitted via some bodily fluids.
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The Public Health Agency of Canada has assessed the overall risk of the Zika virus to Canadians as “very low.”
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