ENC Researcher Warns About Texas Floodwater Pathogens

Sep 1, 2017

A local researcher wants to raise awareness of bacteria and viruses lurking in the stagnant floodwaters in Texas.  

Credit UNC

You’ve heard about flooding in Texas…rescuers pulling people from stranded vehicles, families wading through the floodwaters to get to higher ground.  Eastern North Carolina is no stranger to being inundated with massive amounts of rainfall from tropical systems. These swift moving waters damage property and pose serious health risks.  For decades now, local researchers at the Institute of Marine Sciences in Morehead City have been studying stormwater impacts and the bacteria, viruses and chemicals that thrive in warm turbid conditions.  Jared Brumbaugh has more on how eastern North Carolina based research will help those affected in the Lone Star State deal with the aftermath of Harvey.

Eastern North Carolina is empathizing with Texas as they deal with record flooding.  This week, nearly 700 Marines from Camp Lejeune were sent to assist with relief efforts.  Five swift water rescue teams from various fire departments across North Carolina were sent to help people in College Station, Texas stranded by floodwaters. 

Once the rain stops, slowly the stagnant floodwaters will start to recede and then another public health risk will emerge.  It’s a scenario all too familiar for folks in eastern North Carolina as devastating flooding from Hurricane Matthew washed human and animal waste, coal ash and other contaminants into Cape Fear, Neuse and Pamlico tributaries. 

“I mean, we’re homeless right now.”

Just last fall during Hurricane Matthew, residents waded through rising water to rescue items from their homes, a scene I witnessed in Washington…

“We’re doing the best we can.”

To business owners assessing damage after the flooding subsided on Highway 70 in Kinston…

“This carpet is destroyed, we’re going to have to replace all the carpet.”

In counties like Beaufort, Craven, Lenoir and Wayne, many people in 2016 were exposed to potentially dangerous floodwaters, harboring harmful bacteria and pathogens.  And now that Texas soon begins the recovery process, Professor at the University of North Carolina’s Institute of Marine Sciences says it’s important for folks to take the precautions to keep disease at bay.

“A lot of people don’t know about some of the risks that are posed and they are so busy dealing with more serious concerns.”

The swift water rescue crews from North Carolina helping out in Texas know all about the health risks.  State Department of Public Safety spokesperson Keith Acree says the 92 firefighters assisting with evacuations will be wearing protective gear and are rigorously trained to decontaminate their equipment.

“It’s cleaning yourself off, cleaning your gear off when you get done with a mission. They have protective gear that they can wear to protect them so they’re not in directly in contact with the water, so they have layers on.”

It seems simple, but Dr. Nobel says good hygiene can ward off infections brought on by organisms and chemicals typically found lurking in floodwaters.

“Things like Salmonella, E. coli, Campylobacter.  Those are names of bacterial groups that people might have read about. In addition to that, some of the more serious and more what I would call emphatic infections can come from viruses like Norovirus. Most people would be familiar with Norovirus because of the recent outbreak that was seen at Chipotle. Another type of virus that’s very important is Adenovirus.  Those are viruses just simply put that if you ingest them, the likelihood of illness is great.”

Nobel says gastrointestinal symptoms associated with bacterial infections and viruses generally pass in two to three days.  However, Salmonella and a particular strain of E. coli, 015787 can cause prolonged infections.  Vibrio bacteria, a naturally occurring bacteria found in floodwater, can precipitate long term health concerns.  It’s the same bacteria that makes raw oysters unsafe to eat because they thrive in warm temperatures.  

“They can actually cause wound infection which can cause very, very serious damage. And certainly life-threatening conditions for a long period of time.  Sometimes people can battle those infections for weeks or months, and then even at that point, suffer an amputation of a limb or a finger.”

In 2005, after Hurricane Katrina, Vibrio infections killed five people and 22 people lost limbs.  Katrina, as with Hurricane Harvey and Matthew, caused record breaking flooding which resulted in warm, standing water.  Nobel says is the perfect environment for Vibrio to thrive. 

Despite geographic differences, the factors that trigger waterborne illnesses in floodwaters are the same, whether they happen here or along the Gulf Coast.

“You still have really high levels of ground water.  And that ground water even slightly below the surface of the land is submerging the conveyance systems that we use to carry our sewage away from our homes and businesses.  So things like septic systems and sewage pipes that would normally function just fine, when they’re inundated, they’re not going to function the way they were designed.”

Leaching septic tanks combined with sediment from the ground create the perfect conditions for bacteria like Vibrio to thrive.

“They’re just as prominent here in North Carolina as they are in Houston it’s just that normally, the population of those bacteria, the numbers are kept in check. But whenever we have these storms, there’s a certain number of factors that really promote their growth.”

More than 50 inches of rain has fallen in parts of Texas, but floodwaters continue to rise.  In Beaumont, levels are expected to rise to 82 feet.  It’s anybody’s guess as to when concerns of floodwater contamination will be allayed.

Dr. Nobel is a professor at the University of North Carolina’s Institute of Marine Sciences.  She’ll be interviewed on Science Friday on September 1st on PRE, Public Radio East News and Ideas about the health impacts of floodwaters from Harvey.