Zika Won't Go Global Because of Olympics, CDC Says

Will the 2016 Olympic Games in Rio de Janeiro lead to global spread of Zika? Some health officials have voiced dire warnings to that effect.

The US Centers for Disease Control and Prevention has assessed the risk and concluded it is minimal.

For most Zika-free nations, there is only an "unlikely scenario that Zika importation would be solely attributable to travel to the Games,” CDC analysts Ardath Grills, PhD and colleagues wrote in a risk assessment published online today in Morbidity and Mortality Weekly Review.

While there are dozens of nations that do not now have Zika sending athletes and supporters to the games, only four of them have climates that would sustain mosquitoes carrying Zika.

The four countries at risk are Chad, Djibouti, Eritrea, and Yemen. The CDC’s conclusion is based on an analysis that shows that virtually no one from those four nations goes to Rio currently so once they do, the odds are that the virus could hitch a ride on Zika-exposed travelers’ return trips. The four countries are sending a total of 19 athletes to the games, plus a delegation of 60 non-athletes.

Another 15 nations participating in the games do not have Zika now, but their climates would not likely sustain viral spread.

The team included all 206 nations participating in the games in its study.

Their report also includes the CDC’s warnings advising pregnant women to stay away from the games, and urging both men and women to avoid getting mosquito bites both during the stay in Brazil and for three weeks afterwards. Men should use condoms for at least 8 weeks after travel even if they are not infected and for six months if they have the infection.

Men with pregnant partners should use condoms or abstain from having sex for the duration of the pregnancy.

Couples should wait 8 weeks before attempting to conceive and wait six months if the potential father has the virus.

Brazil is one of 49 countries and US territories in the Western Hemiphere where Zika is known to be a problem. Infection poses risks of sexual transmission that is associated with birth anomalies including microcephaly in babies born to infected mothers. Otherwise, tthe illness is usually mild and flu-like but can have complications.