Scientists sound the alarm as dangerous amoebas spread globally

Date: June 6, 2026 Source: Shenyang Agricultural University Summary: Scientists warn that free-living amoebae may be an underappreciated public health threat, capable of causing deadly infections and shielding other dangerous microbes from water treatment. Climate change and aging infrastructure could help these resilient organisms spread more widely in the years ahead. Share: Facebook Twitter Pinterest LinkedIN Email FULL STORY Scientists are sounding the alarm on tough-to-kill amoebae that can spread disease, survive water treatment, and may become more common as the planet warms. Credit: Shutterstock Environmental and public health researchers are warning that a little-known group of microbes could become a much bigger threat to human health. These organisms, known as free living amoebae, are found in water and soil, but scientists say some species are becoming increasingly concerning as the world warms and water systems age. In a perspective published in the scientific journal Biocontaminant, researchers describe free living amoebae as an overlooked public health risk that needs far more attention. They point to climate change, aging water infrastructure, and weak monitoring systems as factors that could allow dangerous amoebae to spread and become harder to control. Why Some Amoebae Are Dangerous Amoebae are single celled organisms that commonly live in natural environments such as lakes, rivers, soil, and water systems. Most do not harm humans, but a small number can cause severe disease. One of the best-known examples is Naegleria fowleri, sometimes called the brain eating amoeba. This organism can cause a rare but extremely deadly brain infection when contaminated water enters the nose, often during swimming or other recreational water activities. "What makes these organisms particularly dangerous is their ability to survive conditions that kill many other microbes," said corresponding author Longfei Shu of Sun Yat sen University. "They can tolerate high temperatures, strong disinfectants like chlorine, and even live inside water distribution systems that people assume are safe." A Hidden Shelter for Other Pathogens The danger does not come only from the amoebae themselves. The researchers also warn that amoebae can act as living shelters for other harmful microbes. Bacteria and viruses can hide inside amoebae, where they may be shielded from disinfectants and other treatment methods. This allows some pathogens to persist longer in drinking water systems and potentially spread more effectively. Scientists refer to this as a Trojan horse effect, and the researchers say it may also play a role in the spread of antibiotic resistance.