Dr. David Hughes, The Australian team's medical director states that water quality in Rio de Janeiro could be more hazardous than the mosquito-borne Zika virus both for athletes and officials at the Olympics.
The doctor said cases of pregnancy aside, the Zika virus usually results in a mild infection, and 80 percent of those infected often do not get serious symptoms.
Zika virus causes a birth defect marked by an abnormally small head, people especially women should avoid travelling to affected areas, he said.
Hughes said the polluted waters of Guanabara Bay and aquatic venues for other Olympic events in August were another matter when it comes to the threat of illness.
"If someone gets a nasty gastro infection, vomiting and diarrhea, it's not ideal for competing in an Olympic environment."
Recent testes of Guanabara Bay shows that disease-causing viruses linked to human sewage at levels well above what would be considered alarming in the US or Europe. The tests also include the venue for sailing, but also Rio's Olympic venues for rowing, canoeing, open-water swimming and triathlon.
"Rio poses a multitude of medical challenges when it comes to keeping our athletes and officials safe," Hughes said.
"We have had many teams go to Rio, we are aware of the water quality issues. We have protocols in place to minimize the risk, but you can't make the risk zero."
Hughes said he had been contacted by several Australian athletes and officials in the past several days over the Zika virus, but none had indicated they would not travel to Brazil in August.
"A few people have asked advice, and they're generally happy just to receive up-to-date information," he said.
"They're grateful that this all came up six months out and not two months out (from the Games). It gives them adequate time to think about it to make an informed decision."
"It's really important to realize that pregnancy aside, Zika poses less risk to a person's health than mosquito-borne illnesses like Dengue fever or gastro from contaminated water” he added.