WASHINGTON — The Centers for Disease Control has identified the Zika virus in the tissue of two babies who died in Brazil from microcephaly — the strongest link yet between the virus and the birth defect that has stricken developing fetuses, the CDC director told a House panel Wednesday.
"This is the strongest evidence to date that Zika is the cause of microcephaly,” CDC Director Tom Frieden told members of the House Foreign Affairs Committee. He added that the findings did not prove that the virus causes the birth defect and that more tests are needed before the link can be proven definitively.
"Zika is new, and new diseases can be scary, particularly when they can affect the most vulnerable among us," Frieden said.
The CDC is warning pregnant women to protect their babies by avoiding travel to South America, Central America and Caribbean countries such as Puerto Rico, where the virus is spreading fast. Women who are already in those countries should take precautions to protect themselves from mosquitoes, which are the main way that the disease is transmitted, Frieden said.
"Our goal really is to protect pregnant women," he said. "That's our main priority right now."
The virus is not a major threat to the rest of the population. Frieden said that 80% of people who contract the virus will have no symptoms at all. The rest will have only mild symptoms, he said. The virus remains in infected people's blood for about a week, Frieden said.
President Obama on Monday announced that he was seeking $1.8 billion in emergency funding from Congress to combat the Zika virus through mosquito control programs, vaccine research, education and improving health care for low-income pregnant women.
Obama's request includes $355 million in foreign aid to South America, Central America, and the Caribbean. The World Health Organization declared an international public health emergency last week, warning that the virus is strongly suspected to be the cause of a cluster of cases of microcephaly, in which babies are born with abnormally small heads and incomplete brain development.
Health officials in Indiana, Ohio, Tennessee and Delaware have confirmed cases of Zika virus in those states. Although the virus is usually spread by mosquitoes, it can also be transmitted through unprotected sex, blood transfusions or, in rare cases, from mother to child during the birth process.
There is no vaccine to prevent the disease, but one could be developed by the end of 2017 if there are still thousands of cases heading into next year, said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health.
He called that timeline "rocket speed for a vaccine" and said big pharmaceutical companies already are calling him to express interest in developing a vaccine.
Sen. Ron Johnson, R-Wis., introduced a bill Tuesday that would give the Obama administration the flexibility to use existing, unused funds that had been set aside for combating the Ebola outbreak of 2014. The legislation lifts restrictions on the funds to allow it to be spent for response and preparedness related to the Zika virus. Identical legislation is being offered in the House by Rep. Chris Stewart, R-Utah.
There was nearly $3 billion left in the fund as of September, Johnson's office said.
However, Health and Human Services Secretary Sylvia Burwell said the administration does not want to tap into the remaining Ebola funds, even though that disease has been largely contained. She told reporters after a briefing with Senate leaders Tuesday that "we need to finish the job in terms of Ebola” and focus separately on the Zika virus.
A second hearing on the Zika virus and Obama's funding request is scheduled for Thursday before the Senate Appropriations subcommittee that oversees health issues. Frieden and Fauci will testify again.
"We all believe this needs to be dealt with in the best possible way and the quickest possible way," said Sen. Roy Blunt, R-Mo., chairman of the appropriations subcommittee.
The outbreak of the Zika virus in Brazil has raised concerns about the safety of traveling to the Olympic games in Rio de Janeiro this summer.
"Brazil has taken this very seriously," Frieden said, adding that Brazilian officials are working to control mosquitoes there.
