Buzz
As the warmer seasons approach, the hidden predators beneath the water’s surface begin to awaken. Lakes offer the perfect environment for bacteria, parasites, and various pathogens to multiply and thrive. While much remains unknown about Earth’s underwater lifeforms, the knowledge we do have is just as unsettling.
10. Naegleria Fowleri
When most people hear the term “amoeba,” they imagine a harmless, friendly microscopic blob. However, this is far from the case with Naegleria fowleri. Known for claiming the lives of nearly every person it infects, this is no harmless creature. Out of all species in the genus Naegleria, Naegleria fowleri is the only one that poses a significant threat to humans.
Unlike many dangers found in lakes that could harm us, this single-celled organism needs to enter the body through the nose. This distinguishes it from other dangerous lifeforms. Once it enters through the nostrils, it travels up the nasal cavity, acting as a direct route to the brain. Upon reaching the brain, it begins to consume brain tissue. Given this, it’s no surprise that Naegleria fowleri proves fatal in 97 percent of cases. Its symptoms, which include headache, stiff neck, and vomiting, often resemble bacterial meningitis, leading to misdiagnosis until the condition worsens.
Naegleria fowleri is a heat-loving organism, thriving in warm environments. It’s most commonly found in lakes, rivers, and hot springs. Some infections have also been traced back to poorly chlorinated swimming pools. While rare, infection with Naegleria fowleri is still incredibly dangerous, with only three recorded survivors in the United States.
9. Cryptosporidium
With a name that could belong to a psychological thriller, the idea of this parasite entering your body through swallowed lake water is enough to unsettle anyone. Cryptosporidium, also known as “Crypto,” is a genus of microscopic parasites that live in the intestines of humans and animals. Its hard outer shell makes it difficult to eliminate, allowing it to survive both inside the intestines and in places like lakes. It can even withstand treated and chlorinated water.
Crypto is one of the leading recreational waterborne illnesses, often sending children and water enthusiasts rushing to the doctor. It causes intense diarrhea, which is the primary way it spreads. The parasite thrives in the feces of those infected, making it even more crucial to avoid swimming when experiencing diarrhea. If an infected person has diarrhea in the water, it contaminates the entire body of water with millions of germs, including Crypto and its companions.
8. Clostridium Botulinum
Clostridium botulinum bacteria is commonly found in waterfowl and fish. When these infected animals die, their contaminated bodies pollute the water, posing a risk to both wildlife and humans. Approximately 20 percent of botulism cases are caused by the bacteria’s spores entering open wounds, while the rest are due to ingesting contaminated water. Clostridium botulinum does not spread from person to person; transmission occurs through water, wounds, and food.
Although botulism is more commonly linked to food, it differs significantly from typical instances of food poisoning. Still, it is far too frequent, with around 145 cases annually, and can be deadly. Symptoms include difficulty swallowing or speaking, facial weakness, blurred vision, trouble breathing, and paralysis.
7. Giardia
Giardia is a type of microscopic parasite that leads to an infection in the small intestine, causing giardiasis. More people are familiar with Giardia than with other parasites, as it infects approximately three million people annually, making it one of the most common causes of waterborne diseases.
The parasite is typically ingested when a person swallows lake water or untreated drinking water. Giardia is commonly found in regions without adequate water filtration systems. Symptoms of giardiasis include fatigue, nausea, and diarrhea. While these symptoms may not seem severe, they can be life-threatening in areas with limited access to healthcare and medical technology.
In impoverished areas, complications from giardiasis are far too frequent. For young children, dehydration caused by persistent diarrhea can quickly lead to malnutrition, which in turn hinders physical and mental development. A long-term effect of the infection is lactose intolerance, which can persist even after the parasite has been eradicated.
6. Leptospira
The Leptospira bacteria, responsible for leptospirosis, spread through the urine of infected animals. Cattle, pigs, horses, dogs, and even wild animals can carry the bacteria. These animals might not show any signs of illness, yet they can excrete the bacteria for years. Quite unsettling.
What makes Leptospira particularly dangerous is that it doesn’t need to be ingested to infect the body; it can easily penetrate through the skin or mucous membranes. The fact that you can contract it just by wading in contaminated water raises the risks of swimming in lakes to a whole new level.
The effects of leptospirosis can be severe, with the most common symptoms being far from benign. Kidney failure, meningitis, liver failure, and death are frequently linked to it. Even the “milder” symptoms are anything but mild. Many people experience fever, chills, muscle pain, jaundice, and bleeding in the skin or mucous membranes.
5. Legionella Pneumophila
Legionellosis, also known as Legionnaires' disease, was first identified during an outbreak at an American Legion convention in the late 1970s. This was when the new pneumonia strain was discovered. Fortunately, researchers have studied Legionella pneumophila and found that this bacterium naturally inhabits freshwater sources.
People can become infected with the bacteria by simply inhaling contaminated water droplets. These droplets, small enough to be breathed in, carry the bacteria. Another way the infection spreads is through aspirating or swallowing tainted water. The severity of the disease can range from mild symptoms to life-threatening conditions, with one in ten infected individuals estimated to die.
In the early stages, the symptoms closely resemble those of mono, with patients experiencing weakness, fatigue, and a loss of appetite. For those who experience the more severe form of Legionnaires’ disease, lasting neuromuscular and neurological symptoms can persist even after the infection has subsided.
4. Norovirus
Often referred to as the stomach bug or the notorious "cruise ship bug," norovirus is a highly contagious virus that spreads rapidly, contaminating everything it touches. Between 1978 and 2010, it was the second most common cause of waterborne illness outbreaks linked to untreated water. Remarkably, norovirus can persist in water for months, and in some instances, even for years.
The symptoms of norovirus infection begin to show within just a few hours. The effects generally last around three days and typically resolve without medical intervention. The virus causes inflammation of the stomach and intestines. Those living in poverty-stricken areas are at a higher risk of severe dehydration. Children are particularly vulnerable, largely because they tend to put almost anything in their mouths.
3. Dracunculus Medinensis
Dracunculus medinensis, also known as the Guinea worm, is a parasitic nematode. Despite its harmless-sounding name, it is responsible for Dracunculiasis, or Guinea worm disease (GWD), which has a history that dates back to ancient Egypt. Unfortunately, there is no known treatment or vaccine to protect against the Guinea worm.
The concept of this parasite is truly unsettling. Infected individuals may not realize they are carrying the worm for up to a year. When the female worm matures and is ready to release her larvae, she migrates from the connective tissue beneath the skin to the surface. The process of her emergence can take weeks, causing immense pain for the infected host.
Typically, the worm targets the lower leg or foot, where blisters form once it starts to break through the skin. These blisters can lead to secondary bacterial infections if they are left untreated. After the female worm exits the skin, only a small portion of her wriggling body is visible. She then releases her larvae, and if not carefully removed, she may re-enter the body. It's a truly disturbing cycle.
Once again, it’s time to stop drinking water from lakes.
2. E. Coli
Escherichia coli is a bacterium first discovered in infants with digestive issues. Every human body harbors around 1,000 E. coli cells per gram of feces in their gut, indicating that some strains are actually beneficial. Most healthy individuals experience no problems with this microorganism, which resides comfortably in their digestive system.
While E. coli itself is mostly harmless, a few dangerous strains exist that can pose serious health risks even in tiny amounts. These strains can be contracted from a wide range of sources, including agricultural runoff, wastewater treatment plants, septic systems, and fecal contamination. Rain can wash contaminated water into lakes and rivers, making them possible sources of infection.
Symptoms of an E. coli infection vary, ranging from mild discomfort to severe health issues. Common complaints include gastrointestinal problems, skin, ear, and eye infections. In extreme cases, respiratory and neurological complications may occur. Hemolytic uremic syndrome (HUS) is also linked to E. coli infections.
1. Shigella
Shigella is a type of bacteria responsible for causing shigellosis, a diarrheal illness. In the United States alone, this bacterium accounts for approximately 500,000 cases of gastrointestinal distress each year. The takeaway here: Avoid contact with feces and refrain from drinking lake water.
Shigella is another harmful bacterium that lurks in the feces of those infected. Water sources often become contaminated when people improperly dispose of diapers or leave their waste in or near water. The telltale symptoms of shigellosis include diarrhea (often bloody), abdominal pain, stomach cramps, and fever.
Victims of shigellosis may also face serious complications. Some have developed postinfectious arthritis, bloodstream infections, and hemolytic-uremic syndrome (HUS), a severe condition linked to recreational water illnesses. HUS occurs when a bacteria-generated toxin destroys red blood cells, often causing bloody stools and potentially leading to kidney failure.
