TeaHe called the death of a child in Nebraska rare but fatal this summer Naegleria fowleri – More commonly known as the brain-eating amoeba – back in the limelight. The amoeba lives in warm, fresh water and can enter the body through the nose, where it travels to the brain and begins to destroy tissue.
The case underscored a disturbing new reality – climate change is encouraging amoeba to pop up in parts of the US where it is not typical, such as the North and West.
Naegleria Grows best in warm water – temperatures above 30C, and can tolerate temperatures up to 46C, says Charles Gerba, a microbiologist at the University of Arizona. This makes it suitable for spreading in hot climates.
“It prefers warm surface waters during the summer in northern latitudes,” he says.
causes a disease called amoeba primary amoebic meningoencephalitisAnd getting sick is rare – only between 2012 and 2021 31 cases were reported in the USAccording to the Centers for Disease Control – it is incredibly deadly. According to the CDC, only 151. four out of Survived the infection between 1962 and 2020.
in America, Naegleria Generally confined to the southern states, it has spread rapidly north in recent years. a 2021 study showed that even though the rate of infection has not decreased, the amoeba is moving from the southern states to the mid-western regions. It has been found as far north as Minnesota.
Outbreaks have mostly been linked to swimming in lakes, although outbreaks in Arizona stem from the use of hot ground water where Naegleria was growing in a well. Previous cases have shown people contracting the infection through contaminated water used for backyard slip-n-slides or through nasal irrigators.
The pathogen was first discovered in Iowa this summer after someone had died Lake, A nearby weather station recorded high temperatures of about 35C (95F) for two consecutive days during the July 4 holiday, when the swimmer is believed to have contracted the amoeba.
Gerba says most cases occur in men under the age of 18—though it’s not clear why. It is possible that young boys are more likely to participate in activities such as diving in water and playing in sediment at the bottom of lakes and rivers, where the pathogen is likely to live.
Even though amoebas do not cause death, they can cause serious harm. in a guess Naegleria Case in Florida, a teen developed a fever after swimming in salt water, and was later hospitalized and suffered seizures. gofundme established to support her care.
Warm temperatures not only facilitate the survival and growth of pathogens such as NaegleriaThey push people even more into the water, which can increase their risk, says Yun Shen, an environmental engineer at the University of California Riverside.
The climate crisis is also increasing extreme weather events – such as floods and droughts – which can introduce more pathogens into the environment. “In dry areas, pathogens will be concentrated in water bodies, which can increase the exposure dose of pathogens when humans are in close contact with water bodies,” Shen says. In flooded areas, water can transfer pathogens into the environment – for example, floods can bring pathogens from soil or aquatic environments into homes and buildings, or cause wastewater collections to overflow and spew pathogens into the environment. can.
“In the future, because of climate change, people living in colder regions may also be exposed to warmer climates and more likely to be exposed to pathogens,” Shen says.
Understanding where the pathogen lives is challenging because there is no rapid test for its presence or abundance in any body of water. And what’s even more frustrating is that it’s still unclear why some people get sick from amoebas and others don’t, the CDC says. After all, millions of people swim in warm fresh water every year, and only a small number of people are infected. This makes it challenging to create an acceptable level to regulate.
As experts continue to observe these changes, Gerba recommends some precautions for swimming in natural fresh water. In areas with warm fresh water it is best to avoid keeping your head under water to prevent water from getting into the nose. Another option is to wear a nose clip, especially for children, he says. Soil and soil in these areas can also become infected, so experts say to avoid digging or disturbing the sediment.
“As surface water temperatures move north, we expect more cases in the future,” Gerba says. “I expect this trend to continue.”