Water at Races - Where Does it Come From?

Facebook flames erupted from walkers and runners who got sick during and after the Las Vegas Rock 'n' Roll Marathon and Half Marathon. Many point fingers at the water. Per common practice at big races (this one had 44,000 participants) they used a hose from a fire hydrant at the water stops to fill large, new trash containers lined with trashcan liners. Then pitchers were dipped into the water, cups filled, and handed to racers. The same water was used to mix up electrolyte sports drink (Cytomax) from powdered mix.

I drank the water at almost every water stop and didn't get sick. My race review. Others began to vomit 1-2 hours after the start. Racers, whether they got sick or not, are invited to fill out a survey from the Southern Nevada Health District to identify whether there could have been an outbreak related to a common source before or during the race.

Update 12/15: The interim report issued on by the health district concluded that the water was an unlikely source of the illness. Their survey seems to point towards it being a viral infection picked up by racers 24-36 hours before the race.

Here is my analysis of this situation:   I've been a walking event coordinator and volunteer for over 25 years. For our events, we fill our club's five-gallon water jugs from taps or spigots and fill cups from the tap on the jug. Using a larger trash container and a hose from a hydrant or spigot makes sense for larger events. The fire department provides the meter to tap a hydrant, and with proper flushing the water should be no different from what comes out of the water fountain nearby.

There could be chemical residues in the trash can liners, as some point out that some bags are treated to prevent smells. I didn't know that before and it is a concern. I'm a registered medical technologist (MT ASCP and CLS CAP) who practiced in the microbiology lab (as well as having my food handlers permit) and I don't know of any microbes or fungus or virus that could cause symptoms so fast. All the ones I know of take many hours to days to produce symptoms. Chemicals such as soaps, detergent, disinfectants, etc. could produce reactions much faster. Update 12/15: the health district interim report says these might cause vomiting at the event, but don't explain diarrhea, which takes a longer time to develop.

Should you expect bottled water at big events? Environmentally and as an event director, I am horrified at the logistics and recycling issues of transporting bottled water to over a dozen water stops along the course. Volunteers risk injury unloading those heavy containers from trucks. A five-gallon jug weighs at least 41 pounds. A package of 24 water bottles weighs at least 25 pounds. Racers can trip on discarded water bottles (as some did in Las Vegas on bottles the racers brought along themselves.) Paper cups make enough trash, but are biodegradable.

Can you imagine the impact of half a million water bottles at the water stops for a race? Just the gas to transport them to and from the event is a major environmental factor.

My personal suggestion is that racers who don't trust tap water should do as I do. I wear a Camelbak hydration pack filled with enough water to get me through the race. I don't do it because I don't trust the water at the water stops. I do it because I have often found water stops out of water, or to be able to take a drink after eating an energy bar or pack of energy gel. The cardinal rule of race hydration is "drink when thirsty," and the sure-fire way to be able to do that is to carry it with you. As a walker rather than a true racer, this makes sense for me. Your mileage may vary.

There were also concerns that the water stop volunteers weren't wearing gloves and often have their fingers inside the cups. As a lab professional and former waitress, I have no strong concerns about that. I have to trust that they, like cooks and wait staff and the last person to touch a doorknob, washed or sanitized their hands after using the toilet. At least I know that by the time I go through the water stop, their hands have been thoroughly rinsed by all of the water splashes they have endured. I'd bet their hands are far cleaner at that point than those of the chefs who prepared my dinner the night before.

What made the racers sick?

• My amateur-epidemiologist guess is that they may have contracted a norovirus (also known as the cruise ship virus) in the days before the race. This could have happened with shared contact from restrooms, doorknobs, handrails they used during the Expo, at the airport, hotels, etc. The stress of the race caused many to become symptomatic at about the same time.Update 12/15: the health district interim report says no norovirus was found in the samples tested, and they would be testing for viruses that cause similar illnesses -- sapovirus, astrovirus and adenovirus.
• Improper hydration and salt replacement leading to dehydration and hyponatremia: Due to the crowding and the race being unable to keep up with filling water cups and mixing the Cytomax sports drink, many racers were at risk. There was no Cytomax at all provided by the time I came through water stops. Many racers said they couldn't get through the crowd to get to the water tables throughout the race, or the tables were empty because the volunteers couldn't fill cups fast enough. This can cause dehydration and hyponatremia. This can come on fast in the dry, cold night we were racing in. I was far thirstier during the race than I expected. Update 12/15: the health department's survey showed that those who drank the water were more likely to have had symptoms, but those who drank the Cytomax mixed with the same water were not more likely to get ill. In my mind, that is a clue that those who were nauseated and vomiting may have been experiencing hyponatremia due to lack of salt replacement and overhydration with plain water. In a study of runners at the Boston Marathon in 2002,  14% had hyponatremia. That would be over 6000 runners at the Las Vegas event.
• Crowding and coming to a standstill at the finish line: The crowding at the starting line was scary to me (and I've done this race and others before with 30,000 or more starters - this was the first time I was scared). Then the biggest bunch of finishers encountered a complete standstill at the finish line due to the positioning of the mandatory photo booths. All racing experts recommend to keep moving after the finish to help cool down and prevent cramping and other symptoms. There was further congestion and delays of an hour or more when racers had to go into the Mandalay Bay convention center and encountered thousands more people streaming out of two other large events being held there. It is no wonder than many racers vomited in the hallways.
• Small possibility of chemical residues from the trash can liners, hoses, stagnant water, or act of mischief/terrorism. Update 12/15: the health district's interim report said that such chemicals might cause nausea and vomiting, but would not explain the symptoms of those with diarrhea.

We may never know the cause, but cases like this make me want to join the CDC as a outbreak investigator.

Sources:

Brian Labus, MPH, Senior Epidemiologist. "Gastroenteritis Outbreak Among Competitors at the 2011 Rock 'n' Roll Las Vegas Marathon & 1/2 Marathon - Interim Report." Southern Nevada Health District. December 15, 2011

Christopher S.D., et.al. "Hyponatremia among Runners in the Boston Marathon." N Engl J Med 2005; 352:1550-1556. April 14, 2005

Photo © Wendy Bumgardner - Water Stop near the Stratosphere at the 2011 Las Vegas Rock 'n' Roll Marathon and Half Marathon