The U.S. Centers for Disease Control confirmed this Wednesday afternoon that the Zika virus is linked to defects in thousands of newborn babies in Brazil, the CDC Director Tom Frieden told members of House of Representatives in Washington.
"Zika is new, and new diseases can be scary, particularly when they can affect the most vulnerable among us," Frieden said during a hearing with the House Foreign Affairs Committee.
The CDC studied four cases in Brazil that have pointed to the strongest link yet between the Zika virus and the birth defect known as microcephaly that has affected thousands of babies in Brazil with abnormally small heads and incomplete brain development. Two fetuses spontaneously miscarried and two babies born with microcephaly who died within a day both had the DNA of the Zika virus in their brain tissue.
“This is the strongest evidence to date that Zika is the cause of microcephaly,” Frieden said, adding that though the data is important, the link is not conclusive. “It's still not definitive.”
A8 We do not know the risk to an unborn baby if a woman is infected with Zika while she is pregnant.— CDC (@CDCgov) February 10, 2016
A8 An increase in no. of babies born w.smaller has been reported from some areas with Zika. #WellnessWed— CDC (@CDCgov) February 10, 2016
Frieden issued a warning to all pregnant women to avoid traveling to South America, Central America and the Caribbean, saying that is where the virus is spreading more quickly than anywhere else.
The CDC head said that women who are already in the regions he mentioned should take precautions against mosquitoes, which is the main way the disease is transmitted. There have also been cases of the virus being transmitted through sexual intercouse and blood transfusions. But health experts admit that the virus, including how it develops and how it can be transmitted, is not well understood.
"We will discover more and more each day," Frieden said.
The official also said that 80 percent of the people who are infected with the virus will show no symptoms at all, while the rest will only have mild symptoms.
The CDC data comes just days after President Barack Obama announced a plan to ask Congress for US$1.8 billion in emergency funding to combat the Zika virus. The funding would support a plan to ramp up research on the virus, including monitoring birth defects that could be linked to Zika, and prevent its spread through mosquito control initiatives.
On Feb. 5, the CDC published a statement on their website warning couples from having sex without using protection.
“Pregnant women with a male sexual partner who has traveled to, or lives in, an area affected by active Zika virus transmission should refrain from sex or use condoms during sex until the pregnancy is over,” the CDC advised.
They also anticipated that the mosquito-borne virus was linked to thousands of cases of microcephaly in newborns in Brazil.
Frieden said the CDC is currently investigating Brazilian research that found Zika virus in the urine and saliva of patients with the disease.
However, he said the CDC would refrain for the time being from warning pregnant women against kissing.
"We're not aware of any prior mosquito-borne disease associated with such a potentially devastating birth outcome on a scale anything like appears to be occurring with Zika in Brazil," Frieden added. "Because this phenomenon is so new, we are quite literally discovering more about it each and every day."
The CDC also announced that experts still do not understand the link, if any, between the Zika virus a neurological condition that can cause temporary paralysis known as Guillain-Barre syndrome.
On Feb. 1, the World Health Organization labeled the Zika outbreak a global health emergency, but also stressed the need for more research.
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