Health experts have issued urgent warnings over deadly pathogens lurking in Texas floodwaters.

Last week, Camp Mystic, a Christian summer camp located along the Guadalupe River, experienced devastating flooding. The tragic event resulted in the loss of 95 lives, including both children and adults, while ten young campers remain missing.

Dozens of campers and people living nearby have been washed away in the days following 12 inches of rainfall, and officials expect the death toll could rise above 100.  

As the water surrounding the camp rose 26 feet, bacteria and parasites linked to everything from stomach bugs to bloodstream infections rose to the surface. 

Experts told DailyMail.com floodwaters are teeming with E. coli, salmonella, legionella and vibrio, which collectively account for millions of illnesses in the US every year. 

Additionally, parasites entering the body through the mouth and open wounds can kill up to one in five patients, with young children like those at the camp being the most vulnerable. 

The experts encouraged people exposed to flooding to steer clear of the water and wear protective gloves and boots to avoid water getting into open wounds. 

They also urged anyone experiencing symptoms like vomiting, shortness of breath, fever or altered mental status to seek help immediately. 

A search and rescue team looks for people along the Guadalupe River near a damaged building at Camp Mystic in Hunt, Texas, on July 7, 2025

Experts told DailyMail.com bacteria like Streptococcus pyogenes (pictured above) could be lurking in floodwater. It can lead to necrotizing fasciitis, which kills one in five patients

Robert Weitz, principal and founder of environmental testing firm RTK Environmental Group in New York City, told DailyMail.com: ‘Floodwater is vastly different from recreational water sources like pools or lakes. 

‘It picks up everything in its path—raw sewage, diesel fuel, debris, storm water runoff, and chemicals—and carries those pollutants into homes, businesses, and streets. 

‘In places like Texas where infrastructure may be strained during heavy storms, these contaminants often include sewage overflow, which poses serious health risks.’

Bacteria like E. coli and streptococcus thrive in the sewage found in floodwaters. 

Weitz added: ‘These bacteria originate from raw sewage and can enter the body through open cuts, the eyes, nose, or mouth, or by touching contaminated surfaces and then your face. 

‘Once inside the body, these bacteria can cause a variety of illnesses, including gastrointestinal infections, skin infections, and in some cases, more serious health issues.’

E. coli originates from animal and human fecal matter and can enter the body through contaminated food or water or by seeping into open wounds. 

It causes gastrointestinal infections leading to bloody diarrhea, stomach cramps, nausea and vomiting. 

While most people recover on their own, about 100 Americans a year die from the bacteria due to complications like hemolytic uremic syndrome – a severe kidney infection – toxins produced by certain strains, dehydration and sepsis – the body’s overreaction to an infection that leads to mass organ shutdown. 

The O157:H7 strain of E. coli was linked to the McDonald’s Quarter Pounder outbreak last year, which sickened 100 people, hospitalized 34 and killed one. 

Additionally, exposure to the bacteria in childhood has been shown in recent research to raise the risk of colorectal cancer, as it leads to DNA mutations in the digestive tract that raise the risk of tumors forming. 

Pictured above are Hanna and Rebecca Lawrence, eight-year-old twin sisters who died in the Texas floods

Streptococcus, meanwhile, is a bacteria that lives in the nose, mouth, throat and genital tract and is usually harmless. However, the strain Streptococcus pyogenes can be found in floodwaters.

This type of bacteria leads to necrotizing fasciitis, also known as ‘flesh-eating disease,’ a severe bacterial infection that spreads quickly and kills healthy tissues. 

The CDC estimates there are 700 to 1,150 cases of necrotizing fasciitis in the US every year. It kills one in five patients. 

Jory Lange, a Houston-based attorney who specializes in food and water safety cases, also pointed to Legionella, which live in lakes and streams. 

He told DailyMail.com: ‘Legionella are bacteria. Inhaled through contaminated water droplets, they essentially cause pneumonia in the lungs called Legionnaires disease between two to 14 days after exposure.’

He estimates Legionnaires’ disease kills one in 10 patients and is ‘especially dangerous for those who are older, who are immunocompromised and anyone who is a current or former smoker.’

Legionnaires’ affects 8,000 to 10,000 Americans every year and kills about 1,000. 

Lange also pointed to the parasites Giardia and Cryptosporidium, which both can be found in floodwaters.  

Giardia causes the gastrointestinal illness giardiasis, which strikes 1.2million Americans per year. The risk of death is extremely low, according to the CDC, but it can lead to diarrhea, stomach cramps, bloating, fatigue and nausea up to 25 days after initial infection. 

Cryptosporidium, which lives in infected human and animal feces, causes cryptosporidiosis, a diarrheal disease that can lead to dehydration. It sickens nearly 750,000 Americans every year.

Lange said: ‘Most of these parasites cause symptoms similar to food poisoning but are not often caught because lab testing is needed to diagnose.’ 

Pictured above are items from inside one of the flooded cabins at Camp Mystic, an all-girls Christian camp in Texas

Avi Santos, 23, a civilian from San Antonio, Texas, wades the water at the Guadalupe River as he helps in the recovery effort near Camp Mystic

Weitz said the risk of illness is highest after flooding ‘when cleanup isn’t done quickly and thoroughly.’ 

He added: ‘The most important steps are to act quickly and clean thoroughly. First, remove the water and dry out affected areas with fans and dehumidifiers. 

‘Any wet items that can’t be properly cleaned—like carpets, makeup, toys, and cardboard boxes—should be discarded.’

He also suggested having professional mold and bacteria testing done on property affected by flooding. 

Weitz said: ‘Without testing, you can’t know what contaminants may be present.’ 

Layering up with gloves, boots, long-sleeved shirts and full-length pants is also key, Lange said. 

He told this website: ‘Wearing protective gear is always a good idea when it comes to any pathogen. If there is exposure, handwashing and sanitizing clothing, surfaces should be done quickly and often. 

‘If there are wounds, they should be washed and disinfected immediately and get medical help right away.’