The World Health Organisation (WHO) said on Tuesday (14 June) that there is only a “very low risk” of the zika virus spreading internationally following the Rio 2016 Olympic and Paralympic Games.

A special committee of the WHO had been tasked with analysing the potential risks of zika transmission from mass gatherings, especially Rio 2016.

Reporting the committee's findings, its chairman Dr David Heymann said "the committee concluded that there is a very low risk of further international spread of zika virus as a result of the Olympics and Paralympics."

Brazil will be hosting the Games during the southern hemisphere's winter, when dry and cold conditions are expected to reduce the population of the mosquitoes that transmit the zika virus. "The intensity of transmission in Brazil is at its lowest in August and September," Dr Heymann said.

The Brazilian health minister said on Friday (10 June) that the number of new cases of zika registered in Rio fell from 2,116 in the third week of February to 208 in the first week of May, a reduction of 90 per cent.

The WHO said that control measures being carried out in Brazil, such as regularly inspecting the Olympic venues for pools of stagnant water where mosquitoes could breed, would contribute even more to the decrease in transmission.

"The risks are no different for people going to the Olympics or Paralympics than they are for people going to other areas where there are outbreaks of zika,” Dr Heymann said.

Rio 2016’s chief medical officer explains why Games will be safe for athletes and visitors

The chairman of the WHO committee on the zika virus , Dr David Heymann, answered questions from journalists in Geneva on Tuesday (Source: WHO/Twitter)

Countries with experience of zika, including Brazil, Cabo Verde, Colombia, France, and the USA, provided evidence to the committee.

Dr Heymann reiterated the recommendations of the WHO for international travellers. The Geneva-based organisation, an agency of the United Nations, is advising athletes and visitors to Rio de Janeiro, and other areas where the zika virus is circulating, to protect themselves from mosquito bites by using insect repellents and by wearing clothing – preferably light-coloured – that covers as much of the body as possible. 

Because the virus can be sexually transmitted, visitors should practise safe sex or abstain from sex during their stay and for at least eight weeks after their return. Pregnant women are advised not to travel to areas with ongoing zika virus transmission, including Rio de Janeiro.