Solo’s teammate, Alex Morgan, said the risk of contracting Zika in Brazil “is kind of scary” and “definitely a concern.”

The Zika outbreak should force the Rio Olympics to be postponed or moved, argues Canadian doctor and professor Amir Attaran in the May issue of the Harvard Public Health Review. ”Simply put,” Attaran writes, “Zika infection is more dangerous, and Brazil’s outbreak more extensive, than scientists reckoned a short time ago.” He mentions that Rio de Janeiro’s 26,000 suspected Zika cases are higher than anywhere else in Brazil, and its Zika incidence rate—157 per 100,000—is the fourth worst.

Though the virus is bound to spread globally, “it helps nobody to speed that up” by bringing half a million travelers to the center of the outbreak so they can then carry the disease around the world, Attaran writes.

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