The Rio Olympics should be moved or postponed because of the ongoing Zika virus, according to more than 150 global health experts.
In an open letter to the World Health Organisation (WHO) and the International Olympic Committee (IOC), the group, including a former White House adviser, called for the Games to be moved to another location or postponed "in the name of public health".
The letter states that the Zika virus has more serious medical consequences than previously known and that the emergency contains "many uncertainties".
Professor Amir Attaran, one co-authors of the letter, told the Press Association that the Games risked becoming "the Olympics of brain damage" if they went ahead this summer.
WHO declared the Zika epidemic to be a global emergency in February and in its latest assessment this week, said it "does not see an overall decline in the outbreak."
The experts, many of whom have worked with the WHO, also voiced concerns over the relationship between the UN's health agency and the IOC, who they said entered an official partnership in 2010.
Prof Attaran called the partnership "beyond the pale" and called into question the independence of the WHO.
He said: "It is ignorant and arrogant for the WHO to march hand-in-hand with the IOC. How can it be ethical to increase the risk of spreading the virus?"
"Just because a fire has begun doesn't mean you need to pour gasoline on it."
On Friday the IOC announced a new campaign with the WHO in battling child obesity and said they had been working with the health body "for over 20 years."
Professor Attaran added that allowing the Olympics to go ahead would lead to the birth of more brain damaged children.
The majority of those infected with Zika will have no symptoms, but for others it can cause a mild illness with symptoms including a rash, fever and headache.
Serious complications that arise from infection are not common, but experts have said the virus can cause microcephaly, where babies are born with abnormally small heads due to the fact their brains have not developed properly.
Some 500,000 foreign tourists are expected to attend the games, which would lead to the virus being spread across the globe to areas it may not have reached if it was not for the Olympics, the letter warned.
Pregnant women have already been advised not to travel to Rio and the WHO have predicted the Zika risk in August would drop since it will be the south American winter and there should be fewer mosquitoes.
The letter dismisses this claim because many visitors to Rio may return to countries with a hotter climate.
WHO director-general Dr. Margaret Chan said earlier this month that the UN health agency is increasingly worried about Zika but stopped short of recommending the Olympics be moved or postponed.
No Olympic Games have been moved because of health concerns, but in 2003 Fifa moved the Women's World Cup from China due to the respiratory virus Sars.
The opening ceremony of the Olympic Games is due to take place at Rio's Maracana Stadium on August 5.