Fear of the Zika virus is intense in Brazil because of its apparent link to a birth defect. After a fact-finding mission in Brazil, Dr. Margaret Chan, who heads the World Health Organization, said the situation "can get worse before it gets better."
Chan called the Zika virus a much bigger menace than the Ebola epidemic in West Africa that killed more than 11,000 people, given the magnitude of Zika's spread and its possible link to microcephaly, a birth defect involving brain growth that leaves babies at risk of a host of long-term developmental issues.
The WHO, governments of affected countries and U.S. health officials have made Zika a top priority.
Dr. Anne Schuchat of the Centers for Disease Control and Prevention and Dr. Anthony Fauci of the National Institutes of Health stressed the need for special funding to continue research on the disease, work on a vaccine against it, and help U.S. states and territories prepare for the virus's spread. They spoke before committees in both the U.S. House of Representatives and Senate.
"We need to prepare to respond in Puerto Rico," Schuchat said. The Zika virus is circulating in Puerto Rico, which is a U.S. territory. "We need the rest of the U.S. to be ready, because travelers will be returning from these affected areas. And we need to work with international partners on the ground to learn as much as we can so that we can protect Americans."
Forty million to 50 million people travel between the U.S. and Latin America each year, and the type of mosquito that carries the Zika virus lives in much of the United States. While U.S. public health officials expect some transmission in the southern part of the U.S., they don't expect Zika to be a major worry. Most of the cases of Zika in the U.S. have been in people who traveled to the affected regions. The CDC is investigating sexual transmission and has confirmed that a woman in Texas got the virus from a male sexual partner.
A pregnant woman holds a mosquito net in Cali, Colombia, Feb. 10, 2016. The Colombian Health Ministry began delivering mosquito nets for free to pregnant women to prevent the infection by Zika virus, vectored by the Aedes aegypti mosquito.
The CDC is working with health ministries in Colombia and Brazil to determine whether the virus causes Guillain-Barré syndrome, a serious type of paralysis, as well as microcephaly.
Fauci told the committees that the link between Zika and microcephaly, while still unproven, was getting stronger.
"There have now been several instances in which the virus has been actually demonstrated in the brains of these babies who died at autopsy, as well as in placenta and amniotic fluid," he said. "So although all of us are reluctant to say there's definitive evidence, it is really quite strong."
U.S. health agencies were heavily involved in the Ebola outbreak in Africa and remain involved in curbing diseases throughout the world. CDC Director Dr. Tom Frieden told VOA during a trip to Addis Ababa that while Ebola and Zika are different viruses, having good public health systems in every country around the world is essential.
"The main lesson from Ebola was that every country has to be prepared to find, stop and prevent health threats," he said. "If we’re not, that country is at risk, the region is at risk, their neighbors and the world is at risk."
Zika is a new threat and scientists don't understand exactly what's happening with it, but they agree much needs to be learned, and learned quickly.