Zika's not the only health concern for athletes heading to Rio, now they need to worry about the water, which is heavily contaminated with raw human sewage.

FOX's Alex Hein reports in this "Housecall for Health":

This is Housecall for Health.

In addition to Zika, athletes are now being warned about another health hazard in Rio, as the waterways are contaminated with raw human sewage teeming with dangerous viruses and bacteria.

With more than 1,400 athletes at risk of getting violently ill during water competitions, tourists are also facing potential risks as they flock to the golden beaches of Ipanema and Copacabana.

Experts say swimmers and athletes who ingest just three teaspoons of water are almost certain to be infected with viruses that can cause stomach and respiratory illnesses and more rarely heart and brain inflammation.

Athletes have been taking precaution to prevent illnesses like taking antibiotics, bleaching oars and donning plastic suits and gloves to limit contact with the water. One expert has advice to travelers and Olympians alike: Don't put your head under water.

For more on this story, check FOXNewsHealth.com.

Housecall for Health, I'm Alex Hein, FOX News.

Follow Alex Hein on Twitter: @Ahlex3889