Even as some athletes say they won't go to Brazil this summer for the Olympics because of the Zika outbreak, the head of the Centers for Disease Control and Prevention said Thursday there's no reason people shouldn't travel to the games.

“We don’t see a public health reason to postpone or cancel the Olympics,” Dr. Tom Frieden said during an address to the Atlanta Press Club.

His statement comes as the World Health Organization’s Emergency Committee on Zika prepares to take up the travel question in the next couple of weeks. So far, both health agencies have said people shouldn’t change their Olympic travel plans in light of the outbreak.

Late last month, the WHO issued a statement saying cancellation of the event “will not significantly alter the international spread of Zika virus.”

The CDC has had teams of researchers in Brazil since the virus picked up speed earlier this year. The country has been the epicenter of the outbreak in the Americas. Because of this, Frieden said, "there's likely to be some transmission in Brazil during the Olympics."

The CDC has been in constant contact with the U.S. Olympic Committee and will provide “any help they need” during the games, which begin in August.

Perhaps the only athletes or travelers who should not attend or participate the Olympics would be those who are pregnant or planning to start families in the near future, Frieden told the press club. Zika causes severe birth defects in fetuses. There is no treatment or vaccine for the virus, which is primarily transmitted by two types of mosquitoes. In that way, it "hitchhikes in the blood of people," Frieden said. It is also sexually transmitted.

What this means for Olympic travelers is a question athletes and fans will have to weigh for themselves, Frieden said.

“Anytime you travel there’s a risk,” Frieden said. “You make a decision every time you travel, is it worth the risk?”