Out of the half million tourists expected at the Rio Olympics just one is expected to catch Zika, Brazil's health minister said today.
However pregnant women should still keep away out of precaution, he said.
Facing international concern over Zika less than two months ahead of the Olympics, Health Minister Ricardo Barros told journalists that chances of catching the mosquito-carried virus in Rio de Janeiro will be almost zero.
"The statistical forecast is that out of the 500,000 foreigners coming to the Games in Rio, less than one tourist will be infected," he said.
Barros said the figure was extrapolated from studies into the spread of dengue -- a disease transmitted by the same mosquito -- during Brazil's hosting of the football World Cup in 2014, when three out of 1.4 million tourists were infected.
Despite Brazil's reassurances, there is mounting international worry about Zika, which has spread rapidly across much of Latin America. In most cases the symptoms are similar to a cold or flu and not dangerous, but pregnant women who contract Zika risk giving birth to children with severe defects, including an abnormally small head and brain.
In an added complication, there is limited, but growing evidence that Zika can be transmitted sexually.
Brazilian officials insist that the Olympics will be safe, because they take place in the southern hemisphere winter when mosquito numbers plummet. In addition, sporting sites will be regularly fumigated.
However, Barros said the World Health Organization's call for pregnant women not to travel to Brazil is "a reasonable measure." The WHO issued an updated guideline this week also urging all women in Zika-affected areas to consider delaying pregnancy.
The Brazilian health ministry says that the Zika outbreak peaked in February with 16,059 cases, while in May the number was 87 per cent down at 2,053.
Last month, 150 scientists signed an appeal to the WHO to ask for moving or delaying the Olympics because of the risks of the still mysterious virus. Barros says Brazil rejects this as "having no scientific basis."
However, the crisis has become a public relations nightmare for Olympic organizers already trying to push back against fears of high crime in Rio and heavy pollution in the bay where sailing contests will take place.
"Brazil is on the front line of aiding and informing the public on this virus," Barros said. "It's not an alarming situation but we have to keep careful watch.
