The World Health Organization (WHO) recently announced that fears about the mosquito-borne Zika virus should not halt the Olympic Games in Rio de Janeiro, Brazil. The global health organization said that athletes and visitors should go forward with their travel plans. However, WHO continues to urge pregnant women to avoid the Games.

WHO Says Zika Virus Is Hampered by Brazil’s Weather

WHO officials cited Brazil’s climate as a deciding factor. The Olympics are slated to begin August 5, 2016, in Rio. Since August marks the beginning of winter in the Southern Hemisphere, cold weather is likely to lower the mosquito population.

What’s surprising about WHO’s statement is that “winter” in Brazil looks a lot like summer or spring in other parts of the world. The average temperatures expected during August range between 75℉ and 80℉ (24℃ – 27℃).

Zika Is Spread by Mosquitos, Sex, and Blood Transfusions

Zika is spread to humans by mosquitos. Once a person contracts the Zika virus, it can also be contracted sexually or via blood transfusions. In adults, Zika infection usually results in tolerable symptoms and very few deaths.

Zika Babies Can Be Born With Birth Defects

However, pregnant women who contract Zika are much more likely to deliver babies who suffer from microcephaly, a birth defect in which a baby’s brain can be abnormally small, underdeveloped, or even nonexistent.

Experts Criticize WHO’s Olympic Announcement

The WHO’s announcement comes despite a letter released in May by the Harvard Public Health Review which urged the International Olympic Committee to relocate or postpone the Games to prevent increased global spreading of the Zika virus.

Other medical experts have also criticized the WHO’s short-sightedness about Zika. A public health and law professor from the University of Ottawa, Amir Attaran, said that  Zika could be devastating to those who don’t even have the means to travel to Rio for the Games:

“People shouldering the risk if [Zika] spreads will be the slum-dwellers in Mumbai, Kinshasa and Lagos who aren’t going to be able to take precautions.”

Another critic, Arthur L. Caplan, a New York University bioethicist said that the WHO was taking an irresponsible gamble by allowing the Games to proceed in Brazil despite the risk posed by the Zika virus. He said that the organization was “betting on the weather, responsible behavior by visitors, adequate mosquito control and a low sexual-transmission rate by returning visitors.”