What will prevent the outbreak is the weather in Rio. The Zika mosquito takes 3 to 4 weeks to reproduce <a href="http:&#x2F;&#x2F;www.denguevirusnet.com&#x2F;life-cycle-of-aedes-aegypti.html" rel="nofollow">http:&#x2F;&#x2F;www.denguevirusnet.com&#x2F;life-cycle-of-aedes-aegypti.ht...</a>
and it loves hot and wet weather.<p>The autumn in Rio is the coldest and driest in a long time <a href="http:&#x2F;&#x2F;g1.globo.com&#x2F;rio-de-janeiro&#x2F;noticia&#x2F;2016&#x2F;03&#x2F;outono-no-rio-sera-mais-frio-e-tera-menos-chuvas-esse-ano.html" rel="nofollow">http:&#x2F;&#x2F;g1.globo.com&#x2F;rio-de-janeiro&#x2F;noticia&#x2F;2016&#x2F;03&#x2F;outono-no...</a>
When the Olympics arrive, the mosquito will be in their lowest population count.<p>If you consider that the Olympics tourists are rich ones, that will spend most of their times in air conditioned environments, the risk is really very low.