The Olympic Games in Rio de Janeiro could look like the movie "Contagion."
In the 2011 film, an American gets sick in Hong Kong and brings the illness back to the US, causing an epidemic. Now a report in the Harvard Public Review argues that the half million visitors who will descend on the Brazilian city could spur a similar spread of the Zika virus.
In the commentary, professor Amir Attaran of the University of Ottawa argues the quadrennial games should be canceled to prevent the disease, which has reached nearly three dozen countries, from spreading further.
"Given the choice between accelerating a dangerous disease or not -- for it is impossible the games will slow Zika down -- the answer should be a no-brainer for the Olympic organizers, too," Attaran wrote. "Putting sentimentality aside, clearly the Rio 2016 Games must not proceed."
Cancelling the games would be a huge decision. They're planned years in advance and require massive investments by the host country. No surprise, the International Olympic Committee (IOC) said the games would go on.
"There is no justification for canceling, delaying, postponing or moving the Rio Games," said IOC Medical Director Richard Budgett, according to the BBC. The IOC said in an email Friday that it remains in "close contact" with the World Health Organization (WHO) and Brazilian authorities on informing athletes and visitors about how to deal with Zika.
Brazil is considered ground zero, where 1.5 million people reportedly may have been infected. The Zika virus has now spread to more than 58 countries and territories, most in Latin America and the Caribbean. The WHO estimates there could be up to 4 million cases of the virus in the Americas in the next year. Zika is known to cause severe cases of birth defects in infants, including microcephaly -- a rare neurological condition linked to babies born with abnormally small heads, and high fever and muscle pain for adults. The virus has also been linked to the paralysis-causing Guillain-Barre syndrome. Some researchers believe it entered Brazil with visitors attending the 2014 World Cup.
In January, the IOC said the Olympics would be safe for athletes and visitors because the games take place during the southern hemisphere's winter months, when the mosquito population is smaller. However, the WHO has also advised pregnant women not travel to any area where Zika virus transmission is ongoing, including Rio.
That's enough news for some visitors, like US women's soccer goalie Hope Solo. On Tuesday, Solo said she'd be going to Rio, despite her concerns about the virus.
Still, it takes only one infected traveler to ignite a health disaster, according to Attaran, who says the IOC is being irresponsible and putting the games before public health. Zika is "flourishing," he wrote, and Rio is "the heart of the outbreak."
Update, May 13 at 7 a.m. PT: Adds further comments from the IOC and the WHO.
This article also appears in Spanish. Read: Zika y los Olímpicos: ¿qué tanto deben preocuparse los asistentes?