GENEVA -- The World Health Organization's chief says the agency is increasingly concerned about the Zika virus, even though it does not recommend canceling or postponing the Rio de Janeiro Summer Olympics in hard-hit Brazil.
"The more we learn about Zika, the more worried we get about it," Dr. Margaret Chan said in a briefing Tuesday in Geneva, saying she herself would be going to the Rio Games.
Chan noted that although Zika has been around for decades, it is only recently that the virus has been proven to cause severe birth defects and neurological problems -- including in newborn children.
She reiterated the U.N. health agency's advice that pregnant women should not travel to Brazil, which has by far the biggest number of Zika cases.
She said the agency was recommending that both Olympic athletes and travelers to Rio take measures to prevent being bitten by the mosquitoes that spread Zika. Still, she didn't see a reason why the games -- which are expected to draw about 500,000 people to Brazil -- should be moved.
"You don't want to bring a standstill to the world's movement of people," Chan said. "This is all about risk assessment and risk management."
Asked if she agreed with WHO's Zika response chief Bruce Aylward, who declared earlier this year that Rio will host a "fantastic" Olympic games, Chan said it will be.
"I'm going," she said.
Chan did not address the Rio Olympics' other big health risk: the filthy, virus-laden waters that sailors, rowers and some swimmers will have to navigate.
In February, WHO declared the explosive outbreak of Zika to be a global health emergency and the virus has now spread to nearly 60 countries.
The agency is constantly monitoring its evolution, and could change its advice to travelers depending on how Zika progresses, WHO officials say.
Some experts have called for this year's Olympics, which run from Aug. 5-21, to be moved or delayed to prevent the avoidable birth of brain-damaged babies. They also warn that the Rio Olympics could spark new Zika outbreaks in other countries and speed up the virus' international spread.
Chan said Olympic athletes were getting advice from their national medical advisers, singling out Australia as one country that has issued "very positive" guidelines to its Olympic team. Other countries are taking measures such as providing protective clothing, window screens and air conditioning "to minimize the risk," she said.
Australia's medical director for the Olympic team said last week that the risk of Zika to athletes was "minimal" and that the last people he had spoken to who had been to Rio recently hadn't even seen a mosquito. The statement made no mention of the fact that Zika can cause the birth of permanently brain-damaged babies.
Chan was speaking ahead of next week's World Health Assembly, a WHO annual event that draws more than 3,500 delegates and addresses six dozen topics -- including resistance to antimicrobial drugs, a global shortage of medicines and vaccines and maternal health.
Despite Chan's concern about the Zika outbreak, not a single session at next week's meeting is focused on the virus, even though Zika is expected to come up in a number of discussions at the assembly.