After months of speculation, the Zika virus has been confirmed as a cause of microcephaly and other birth defects, U.S. officials say.
U.S. Centers for Disease Control and Prevention (CDC) scientists made the conclusion after “careful review of existing evidence.” The findings are summarized in a New England Journal of Medicine special report.
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Zika virus is spread by mosquitoes and has also been found to be transmitted via some bodily fluids.
For months it has been speculated that the virus is linked to birth defects; officials in some countries have even warned women against getting pregnant.
Brazilian officials were the first to raise alarm bells over the link between the virus and microcephaly, after a spike in cases of the birth defect in the country.
CDC officials now say the link is “clear”, but the work to understand the full impact of Zika is just beginning.
“This study marks a turning point in the Zika outbreak. It is now clear that the virus causes microcephaly,” said Tom Frieden, director of the CDC.
“We are also launching further studies to determine whether children who have microcephaly born to mothers infected by the Zika virus is the tip of the iceberg of what we could see in damaging effects on the brain and other developmental problems.”
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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, which is usually the result of the brain developing abnormally in the womb or not growing at a normal rate after birth.
This can lead to developmental issues requiring speech and other therapies. There is no cure.
The CDC is careful to point out that women who are infected with Zika are not guaranteed to have babies born with microcephaly, simply that they are at increased risk of having a child with health problems.
Prevention is key as officials work against time to learn more about Zika and its related health risks, officials say, and in the meantime prevention is key.
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Preventative measures for people in affected areas include avoiding being bitten by mosquitoes and avoiding sexual transmission of the virus. For people outside active areas, avoiding travel has been advised if you or your partner are pregnant or plan to get pregnant soon.
First identified in Uganda in 1947, in the decades following Zika virus was found in Southeast Asia, and by the 21st century had spread to the Pacific Islands, reaching South America around 2014.
Zika has been spreading rapidly in recent months, making its way north from Brazil. A recent study predicted Zika will become “increasingly abundant” in much of the southern and eastern United States as the weather warms.
Brazil is set to host the Summer Olympics and Paralympics this summer; more than half a million people are expected to attend as athletes, volunteers or spectators.
As of April 7, 44 cases of travel-related Zika have been confirmed in Canada. The mosquito that spreads the virus — Aedes aegypti — is restricted to tropical and subtropical regions, and is generally not of concern in Canada.
The Public Health Agency of Canada has assessed the overall risk of the Zika virus to Canadians as “very low to low.”