Understanding the brain-eating amoeba and flesh-eating bacteria

Headlines about the brain-eating amoeba and flesh-eating bacteria can sound alarming. But knowing how to protect yourself and your family from the rare, fast-spreading and often deadly infections that these microscopic organisms can cause can bring you peace of mind.

Life-saving innovations now offer new hope and timely care for people who may be infected.

An AdventHealth medical microbiologist explains how simple precautions can help you safely enjoy the outdoor activities that help you feel whole.

"This isn't just a summer issue anymore. When temperatures rise above 80 degrees -- even in winter -- amoebas can remain active."

Brain-eating amoeba: What you should know

The brain-eating amoeba (Naegleria fowleri) is found in warm, untreated freshwater, including lakes, rivers, hot springs, and even poorly maintained pools and underchlorinated splash pads.

The amoeba can only cause an infection by entering the body through the nose. This happens when a swimmer dives, submerges their head or has water forced into the nose. It can also occur by using tap water in nasal rinses.

Unlike a parasite, which requires a host organism to live, amoebas live freely in water, said Jose Alexander, MD, medical and technical director of the microbiology, virology and immunology laboratories at AdventHealth Orlando.

"When they enter the human body, we become what we call an accidental host," he said. "They're not looking to infect us. They were just in the water that got into the nose."

Dr. Alexander said that taking precautions can prevent infections.

"The amoeba is probably in every lake. As an expert, I always assume that, because it's part of nature," he said. "I would avoid getting into a lake. If I must get into a lake, I avoid putting my head in the water. And even with all of that, if I get into a lake, I use a nose clip to reduce the chance of getting water in my nose, because that's the amoeba’s portal of entry into the body."

Flesh-eating bacteria: What you should know

The flesh-eating bacterium Vibrio vulnificus is found in warm coastal waters.

It can enter the body through cuts, scratches or other open wounds when exposed to saltwater or brackish water.

That exposure can sometimes lead to necrotizing fasciitis -- a rare, fast-moving infection of soft tissue.

The Centers for Disease Control and Prevention says that if you get a cut or wound in coastal waters, wash it immediately with soap and clean running water.

Brain-eating amoeba: Risk and symptoms

The brain-eating amoeba can cause a rare brain infection known as primary amebic meningoencephalitis, or PAM.

It is extremely rare -- only 164 cases have been reported in the United States in the past 60 years. But it is also highly deadly, with a 97% mortality rate. The infection rapidly progresses, often proving fatal within five to 10 days.

In 2016, AdventHealth experts successfully treated one of only four known survivors of this infection. His story shows that with expertise, innovation and timely care, survival is possible. Read his story here.

Dr. Alexander said that more than half of PAM cases occur in children under 14, with males accounting for about 75% of reported infections.

Researchers are uncertain why PAM is more common in young males. Some suggest that it might be linked to exposure patterns -- such as time spent engaging in activities in warm freshwater -- but the precise reasons remain unclear.

Symptoms include fever, severe headache, stiff neck, confusion, nausea, vomiting and seizures. The illness can quickly progress to coma and death.

Flesh-eating bacteria: Risk and symptoms

Each year, 150 to 200 cases of flesh-eating disease caused by V. vulnificus are reported in the U.S. -- 20% of which are fatal, the CDC said. But the rapidly progressing infection can be survivable with early intervention.

"The immune system can limit the infection," Dr. Alexander said. "The treatment can be effective."

He said that it can be more difficult to treat infections in patients with underlying conditions, such as liver disease, diabetes or cancer.

"Any condition that causes some level of immunosuppression decreases the chance for the immune system to fight back," Dr. Alexander said. "This organism will spread quickly."

Symptoms include fever, redness, severe localized pain, swelling, warmth, discharge and rapid skin and tissue death, which may require surgery, including amputation.

The CDC says that you should immediately see your doctor or go to the emergency room if you have symptoms of an infection.

Quicker detection

For both conditions, swift detection and proper treatment are essential to saving lives.

"Time is critical," Dr. Alexander said. "A key factor in the treatment for these cases is a rapid diagnostic."

To support faster answers for patients and their families, he and his team developed a PCR test that quickly rules out the presence of the amoeba in spinal fluid, cutting turnaround time for results from days to hours.

This tool is now available nationwide, allowing more people to receive life-saving treatment sooner.

Dr. Alexander said that promising technologies, such as next-generation sequencing and artificial intelligence, will continue to advance patient care -- offering physicians faster, more accurate ways to diagnose and treat infections.

"At AdventHealth, we believe there is always a reason for hope," he said. "Through innovation and whole-person care, we strive to give patients every possible option for healing so that they can return to the activities that make them feel whole."