Mosquito population during games holds some answers

WHO to take a call on Zika and the Summer Olympic Games in Rio
news Monday, June 06, 2016 - 12:52

The World Health Organisation (WHO) will take a call on whether the Rio de Janeiro Summer Olympics should go ahead as planned as concerns about the Zika virus rise. An expert panel will meet shortly to decide. 

“Given the current level or international concern, I have decided to ask members of the Zika Emergency Committee to examine the risks of holding the Olympic Summer Games as currently scheduled” WHO chief Margaret Chan wrote. She was responding to a letter from a US Senator Jeanne Shaheen who asked the health body to evaluate whether the Rio games this year should be postponed.  The Daily Mail has reported that WHO has sent senior scientists to Brazil four times to assess the risk of Zika to the approximately 500,000 athletes and visitors expected to attend the August 5-21 games in Brazil. Read here.

At the recently concluded World Health Assembly (WHA), the WHO’s annual meeting of ministers and public health officials, concerns about Zika and the games were mentioned by several countries even as the WHO downplayed the dangers. Brazil has been the hardest-hit among some 60 nations that have reported Zika outbreaks and has by far the most cases of brain-damaged babies – almost 1500 - linked to the virus.

Late last month Canadian professor Amir Attaran write to the WHO head arguing that the Olympics as planned would result in the avoidable birth of more brain-damaged babies. In his open letter to Chan which was signed by 200, Attaran said the games must be postponed “in the name of public health” leading to concerns that the games would turn into the Olympics of brain-damage.  The WHO had rejected that letter, but is obviously having second thoughts now as the US Senator also quotes from Attiran’s letter calling for another assessment.

So who is right - the global health body or Attiran and others who are calling for the games to be postponed? The coming weeks will tell. There’s one critical piece of information that could answer that question and that is the number of mosquitos which will be flying around Rio during the games. It’s winter in Brazil at that time and mosquitoes prefer summer. This may sound ridiculous, but this is what the scientists are trying to figure out. Epidemiologist Mikkel Quam who works at the Umea University in Sweden has told media “…There’s very little mosquito activity during the Olympics.” He has used a mathematical model to predict this and according to it I in 31,000 people at the games will get infected with Zika. Since 500,000 fans and athletes are expected that would mean 16 cases of Zika at the Games.  The European Centre for Disease Control (ECDC) has said attendees are more likely to get flu or food poisoning than Zika.

No one seems to be buying that, certainly not a section of public health advocates who are upping the ante. They say it is only a model and models have little control over several other factors including weather conditions. Then there is the issue of carrying the infection for weeks before it manifests itself. That means where people go after Brazil is also an issue. Most people infected by Zika suffer only minor symptoms including fever, a rash, joint or muscle pain. But the virus can cause several birth defects including babies born with abnormally small heads or a rare syndrome that can cause death or temporary paralysis.

At the WHA, critics said WHO had a close relationship with the International Olympic Committee (IOC) making it incapable of providing an unbiased assessment of the risk. The IOC has refuted those charges. On February 1 2016, the WHO declared Zika as a Public Health Emergency of International Concern (PHEIC) which is a top global alert to countries. At time of writing, the jury seems to be in favour of keeping the games as the event itself is not seen as changing the epidemiological model. The moot question is – what happens afterwards?

This is a developing story.

Read The News Minute’s coverage of Zika.

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