From a medical standpoint, we absolutely shouldn’t cancel the Rio Olympics – Quartz

Latin America has emerged as the epicenter of the Zika epidemic—and that has foreign businesses, medical experts and tourists all weighing the risks of travel abroad. Fanning the flames of the debate this week was a provocative article by Canadian lawyer and biologist Amir Attaran declaring that the 2016 Summer Olympics in Brazil “must not proceed,” released on the heels of Major League Baseball’s decision to move two games from Puerto Rico to Miami last week.

It’s understandable that people will want to take every precaution to prevent the spread of Zika, which has been linked to birth defects in newborns as well as Guillain-Barre syndrome, which causes paralysis in adults. But both Attaran’s article and MLB’s move are alarmist. The truth is that canceling the Olympics would do little to prevent the spread of Zika, while causing real economic damage to Brazil.

Attaran concedes that “Brazil’s Zika will spread globally” regardless of where the Olympics are held. However, he argues that “the mass migration of 500,000 foreigners” to the games this summer is likely to speed up the spread of the virus.

But we’ve got to put the “mass migration” of travelers to the Olympics in context. Almost six million foreigners travel to Brazil every year. The country represents the eighth-largest business market in the world. Tourists in town for the Olympics might well spread the virus—but so can the business travelers working in oil and gas, steel, mining and numerous other industries, all of whom continue to go to Brazil year-round.

Moreover, of the estimated half a million visitors who will travel to Brazil for the Olympics, about half will be Americans—no surprise, since it’s expensive to go. But travelers have already imported Zika into the United States. As of early May, there have been over 400 travel-related cases of Zika in the US. Travelers will continue to bring the disease to the States, whether the Olympics are moved or not. As for the threat to poorer nations with less developed health systems, the fact is that travelers from poor countries that aren’t already Zika-affected will represent only a tiny fraction of those attending the Olympics.

It’s also important to note that the summer months, and with them, mosquito season, will be starting soon in the US. We could see transmission in much of the southern US and even into the Midwest, if the Aedes albopictus—a species related to the Zika-spreading Aedes aegypti—also proves to be an efficient vector. Miami, where MLB relocated the two games to be played in Puerto Rico, will likely be among the cities hardest hit.

Fortunately, in this country, we’re largely protected by better housing, sanitation and health systems. So while we’ll certainly see transmission this summer, it’s unlikely to become the widespread problem facing Latin America.

It is worrisome, as Attaran writes, that reported cases of dengue—a cousin of Zika that’s also transmitted by Aedes aegypti mosquitoes—in Rio de Janeiro are up. Severe droughts in the country have led many to store water in open containers, in which mosquitoes have multiplied. Because Zika is transmitted by the same vector, it stands to reason that this could portend more Zika cases too.

But that’s only part of the story. In years past, cases of dengue have been massively underreported. It’s estimated that there could be as many as 20 unreported cases for each one that is reported. That’s because not everyone who gets a fever, rash and/or joint pain goes to the doctor. Many just suffer it out at home and are never diagnosed.

But now, with the arrival of Zika, people’s radars are up. Patients, especially women of childbearing age, are far more likely to come in for testing if they have symptoms possibly related to Zika. The screening algorithm includes testing not only for Zika, but also its cousins dengue and chikungunya. So at least some of the increase in reported dengue cases is simply because more people are getting tested—what we in public health call a surveillance bias, i.e. “the more you look, the more you find.”

I harbor little sentimental feeling about the Olympics. My husband, a sports journalist who will be covering the Olympics in August, often jokes with me about my lack of interest in sports. But I do worry about how canceling or indefinitely postponing the games would affect Brazilians—economic risks that need to be weighed against Attaran’s what-ifs.

If the games are moved, the ripple effects would impact small businesses, foreign investment and other travel to the region. Brazil is already saddled by the worst economic crisis in decades as well as political chaos—the Brazilian Senate voted on May 12 to commence impeachment proceedings against President Dilma Rousseff. And it’s the poor in Brazil (and elsewhere in Latin America) who will bear the brunt of another hit to the economy.

With the threat of Zika looming in the US, the Senate may finally approve emergency funding to fight Zika—though the amount of $1.1 billion falls far short of the Obama Administration’s request for almost $1.9 billion. Rather than fall prey to fear of Zika entering the US from other countries or distracting debates about moving the Olympics, we should acknowledge that the virus is already here with more cases on the way, and keep the pressure on Congress to do its job of protecting the American people.

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