These 4 countries are most at risk of Zika during Olympics

Thursday, July 14, 2016, 12:47 PM - As the 2016 Olympic games in Rio draw closer, concerns over the risk of Zika transmission have been heightened. However, a new report released by the U.S. Centers for Disease Control says the games are unlikely to cause any further spread of the virus across the world, with the exception of four countries.

The findings echo a conclusion reached by the World Health Organization last month that the games do not need to be postponed or cancelled due to Zika.

The CDC estimates 19 countries that currently do not have Zika have the right environmental conditions and population susceptibility to sustain the virus if a case were imported from a person returning from the Olympics. But of those 19, only four countries face a substantial risk for mosquito-borne transmission of Zika virus. They include: Chad, Djibouti, Eritrea, and Yemen. This is because they have very few travellers to Zika outbreak countries, except for anticipated travel to the games.

These four countries will be represented by a combined total of 19 athletes, which is a small fraction of the estimated 350,000 to 500,000 visitors expected in Rio de Janeiro, the report highlights. However, as of June 30, Chad and Yemen had not qualified any athletes for the games.

In addition, the overall travel volume expected at the Olympics and Paralympics in August and September represent less than 0.25 per cent of the total estimated travel to Zika-affected countries in 2015, according to the CDC analysis.

"Compared with all travel to Zika-endemic areas, the Olympics account for about one-tenth of one per cent of travel from the U.S. and globally about one-quarter of one per cent, so even if Olympics didn’t exist, 99.75 per cent would be the same risk," CDC Director Tom Frieden told reporters Wednesday.

To gain a better understanding of each country's individual risk, the CDC took into account several factors including, whether the country in question has ever had a Zika outbreak, if the country is home to Aedes aegypti, the breed of mosquito responsible for the transmission of the virus, and how much interaction the country has already experienced with Zika-stricken areas.

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Winter in Brazil

One of the key reasons why the overall risk of transmission will be low is due to colder weather. The games will occur during winter in Brazil and the cooler, drier weather will reduce mosquito populations, says the CDC report.

Officials say if athletes and visitors follow precautions to prevent exposure to the virus, the four countries most at risk could be spared Olympics-related outbreaks.

"To prevent Zika virus infection and its complications among athletes and visitors to the Games and importation of Zika virus into countries that could sustain local transmission, pregnant women should not travel to the games, mosquito bites should be avoided while traveling and for three weeks after returning home, and measures should be taken to prevent sexual transmission," the report notes.

SOURCE: CDC report

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