Olympic Games in Brazil come with personal, global health implications

The spread of Zika virus in Brazil happens to coincide with the final year of preparations for the Rio de Janeiro Olympics — the first Olympics ever held in South America.

Unlike Major League Baseball, which relocated a recent two-game series from Puerto Rico to Miami over fears about Zika, Olympic organizers have proceeded as planned amid concerns about the virus and other common illnesses spread by mosquitoes and polluted water in Brazil.

In a recent editorial published in the Harvard Public Health Review, Amir Attaran, DPhil, MS, professor of medicine and law at the University of Ottawa, called for the Olympics to be moved out of Brazil or postponed due to the risks associated with Zika, which he said are more serious than scientists believed even a short time ago.

“But for the games,” Attaran wrote, “would anyone recommend sending an extra half a million visitors into Brazil right now?”

Olympics arrive amid ‘dynamic’ outbreak

The risks of hosting an Olympics in Brazil exist on a personal and global level and could have far-reaching health implications, according Stephen S. Morse, PhD, professor of epidemiology at the Columbia University Mailman School of Public Health and director of the university’s infectious disease epidemiology certificate program.

“There is a concern any time you have a mass gathering of people packed closely together,” Morse told Infectious Disease News. “The diseases we most worry about are those that might land in places where they are not already established.”

This includes Zika, which was discovered in Uganda in 1947 but only recently has been linked to more serious effects, particularly in Brazil, where the outbreak has been described by the CDC as “dynamic.” According to Morse, it is unknown whether the Zika virus circulating in Brazil is more virulent than the strains that circulated decades ago in Africa, or if better science and larger case numbers are making it easier to notice the more serious effects.

Uncertainty is at the heart of concerns about Zika being reintroduced to Africa, which has not reported the same serious side effects of the disease, Morse said.

“Maybe people will come back with Zika virus from South America that won’t behave the same as what they already know,” Morse said. “That’s speculation, but there’s been some concern. Is it going to behave differently? We have no idea. There are a lot of unknowns there.”

Other mosquito-borne viruses such as malaria, dengue and yellow fever are common throughout Brazil, according to the CDC. Yellow fever, which is currently causing an outbreak in Angola, is of particular concern, Morse said. The illness has never been reported in Asia, but WHO considers the continent to be at-risk because the conditions for transmission exist there.

“There has been a lot of concern to keep yellow fever out of Asia, where it still has not established itself or even been introduced except in the rare imported case, which is a very good thing,” Morse said.

Fears about holding the Olympics in Brazil echo recent concerns over the annual hajj pilgrimage to Saudi Arabia. In the past several years, millions of people have traveled to the country at the center of an outbreak of Middle East respiratory syndrome without causing a serious worldwide outbreak.

“On the one hand, we’ve been lucky,” Morse said. “On the other hand, there has been a lot of effort devoted to surveillance.”

In the United States, potentially infected travelers returning from Brazil may be more likely to transmit Zika virus depending on where they land, according to a recent study that determined that southern areas of Florida and Texas were more susceptible to local outbreaks of Zika virus than anywhere else in the country. Researchers found that all 50 cities in the study, from New York to the California coast, can support the Aedes aegypti mosquito — the main vector of Zika — during peak summer months.

The Rio Olympics will be held Aug. 5-21 — winter in Brazil, but a peak summer month in the U.S.

“If infected people come back to areas where there may be the appropriate vectors and the appropriate local ecology, you could now have not only new local cases, but even cases that are locally transmitted,” Morse said. “Then they establish themselves the way that West Nile did when it first came to the U.S. It came to New York and found a suitable vector and ecological situation and managed to establish itself as part of the ecology in most of the U.S. That’s a possibility with Zika in places with the right conditions, such as mosquito species that can transmit the virus.”

Preventive measures for the Games

Prevention appears to be paramount in avoiding Zika virus infection and limiting the spread of the disease. Travelers are urged to protect themselves from mosquito bites, and the CDC has recommended that pregnant women not go to Brazil for the Olympics. The agency says all travelers should schedule a health appointment 4 to 6 weeks before they depart and talk with a doctor about appropriate vaccines and medicine.

Morse said travelers have many things to worry about beyond Zika.

“Dengue would probably be more likely for many travelers,” he said. “Anyone should be taking all of the normal travel precautions that they would take when they travel to any other tropical or developing country, including using mosquito repellents.”

Although Zika virus is primarily spread via the bite of a female Aedes aegypti mosquito, it also can be transmitted through sexual intercourse. The CDC’s guidelines for preventing sexual transmission of the virus to minimize the risk for infection in women who are pregnant or plan to become pregnant have so far focused on abstinence and condom usage.

In Brazil, Olympic athletes will have access to 450,000 free condoms that will be available in 41 dispensers, including dispensers in the recreational area and the polyclinic of the athletes village that will be refilled daily by the government, according to Andrew Mitchell, an International Olympic Committee spokesman. The total includes 350,000 male condoms and 100,000 female condoms.

“This is considered to be a sufficient quantity to encourage athletes to practice safe sex while in Brazil for the Olympic Games,” Mitchell told Infectious Disease News.

ID experts working with USOC

In response to Attaran’s editorial, which criticized WHO for being too quiet about the Olympics, the agency released a joint statement with the Pan American Health Organization encouraging visitors to Brazil to practice safer sex and avoid visiting “impoverished and overcrowded” areas with no piped water and poor sanitation, where the risk for being bitten by a mosquito is greater.

In response to the threat of Zika, the U.S. Olympic Committee (USOC) named three infectious disease experts to a volunteer advisory group that will help American athletes and staff prepare for Brazil.

The threat forced USA Swimming to move a planned Olympic training camp from Puerto Rico, which has been hit hard by Zika, to Atlanta.

“The health and safety of our athletes is our top priority,” William J. Moreau, DC, DACBSP, CSCS, Team USA’s chief medical officer for the Rio Olympics, told Infectious Disease News. “We’ve worked hard over the course of the last several years to ensure that all of our athletes are aware of the challenges they’ll face in Rio and have strategies to mitigate the risks associated with those challenges.”

Beyond Zika and other vector-borne diseases, athletes competing in the waterways around Rio, or tourists who decide to swim at one of the city’s famous beaches, should be concerned about water-borne infections while in Brazil, according to Morse.

“People have gone down there for sporting events in boating and swimming and have suffered from some of the pathogens in the water,” he said. “I doubt that’s going to be any different.”

The European Centre for Disease Prevention and Control has classified gastrointestinal illness and vector-borne infections as the main risks to public health during the Rio Games. In a recent report, the agency declared there was a “moderate” risk for infections or outbreaks caused by Salmonella, Campylobacter, norovirus and Escherichia coli during the Olympics, and a “high” risk for an influenza outbreak or transmission.

The decision to go or stay home

Athletes have a tough decision to make, Morse said. As competitors, they have a better reason to travel to Brazil than the general public, and thus might feel more compelled to make the trip.

“I think the decision has largely been that those who are participating should participate if the Olympics aren’t canceled. But they should obviously take the precaution that any traveler would take,” Morse said.

Moreau said athletes are always interested to learn how they can protect themselves.

“There are risks associated with virtually every sport,” he said, “but we’re very confident that Team USA will compete safely and successfully.”

As for spectators or anyone else planning to visit Brazil during the Olympics, Morse said anxiety over the threat of contracting a disease could detract from the enjoyment of being there.

“If they feel really worried about it, it’s probably better to stay home," he said. – by Gerard Gallagher

References:

CDC. 2016 Summer Olympics (Rio 2016). http://wwwnc.cdc.gov/travel/notices/alert/2016-summer-olympics-rio. Accessed May 11, 2016.

CDC. Zika and sexual transmission. 2016: http://www.cdc.gov/zika/transmission/sexual-transmission.html. Accessed May 11, 2016.

European Centre for Disease Prevention and Control. Potential risks to public health related to communicable diseases at the Olympics and Paralympics Games in Rio de Janeiro, Brazil, 2016. http://ecdc.europa.eu/en/publications/_layouts/forms/Publication_DispForm.aspx?List=4f55ad51-4aed-4d32-b960-af70113dbb90&ID=1486. Accessed May 11, 2016.

Monaghan AJ, et al. PLoS Curr. 2016;doi:10.1371/currents.outbreaks.50dfc7f46798675fc63e7d7da563da76.

Disclosures: Mitchell is a spokesman for the International Olympic Committee. Moreau is the USOC’s chief medical officer for the Rio Olympics. Morse reports no relevant financial disclosures.

Photo Credit for Moreau: USOC