Daijiworld Media Network - New Delhi

New Delhi, Jan 3: Free-living amoebae—often referred to as brain-eating amoebae—are increasingly posing a global public health challenge, according to a new scientific study that links their growing threat to climate change and deteriorating water systems.

The study, published in the journal Biocontaminant, highlights how rising temperatures, ageing water infrastructure, and inadequate monitoring are allowing these dangerous microorganisms to thrive in natural and treated water environments. The research was conducted by a team of environmental and public health scientists.

“What makes these organisms especially concerning is their resilience,” said corresponding author Longfei Shu of Sun Yat-sen University, China. “They can survive extreme heat, withstand strong disinfectants such as chlorine, and persist within water distribution systems that are generally considered safe.”

Amoebae are single-celled organisms commonly present in soil and water. While most species are harmless, a few can cause severe and often fatal infections.

The most well-known among them is Naegleria fowleri, which can lead to a rare brain infection when contaminated water enters the nose, typically during swimming or other water-related activities. In recent years, this amoeba has been linked to multiple deaths in Kerala.

Beyond causing direct infections, the study points out that amoebae can act as “hidden reservoirs” for other disease-causing microbes. By hosting bacteria and viruses inside their cells, amoebae can shield these pathogens from disinfection processes, enabling them to survive longer in drinking water systems. This so-called Trojan horse effect may also play a role in the spread of antibiotic resistance.

The researchers warn that global warming could further intensify the threat by expanding the habitat of heat-tolerant amoebae into regions where they were previously uncommon. Several recent outbreaks associated with recreational water use have already heightened public concern worldwide.

To address the growing risk, the authors recommend adopting a One Health approach, which integrates human health, environmental protection, and water management. They call for enhanced surveillance, better diagnostic capabilities, and the use of advanced water treatment technologies to prevent infections before they occur.

“Amoebae are not confined to a single sector,” Shu said. “They exist at the crossroads of environmental and human health, and tackling them effectively requires coordinated, integrated solutions that address the problem at its source.”