The dangerous waterborne microorganism is Naegleria fowleri, also called the “brain-eating amoeba.” This amoeba is seen in warm freshwaters, including rivers, hot springs, lakes, and rarely even water supply systems, with the temperature of water ranging from 25 to 400 °C. This microorganism is mainly responsible for primary amoebic meningoencephalitis, a rare condition that leads to fatal brain infection. It occurs through water contamination that enters the nose, allowing the amoeba to bypass protective membranes and travel to the brain through the olfactory nerve. In the brain, it destroys the tissue and causes swelling, leading to quick and severe disease. Drinking contaminated water does not cause infection; the danger arises only when water enters the nasal passages during nasal rinsing, bathing, and swimming.
The incubation period of this infection is 3 to 7 days. The symptoms include confusion, fever, hallucination, changes in smell or taste, vomiting, sore throat, headache, progressing immediately to seizures/convulsions, and coma. Even with medical treatment, the deaths are generally reported within 5 days of symptoms; therefore, the mortality rate is extremely high.
From 1962 to 2024, the United States reported 167 cases with four survivors. A global review up to 2018 identified 381 cases worldwide with a 92% death rate. Australia accounted for 22 cases, the 5th highest total after Mexico, India, Pakistan, and the U.S. The most infections were detected in young people and children, specifically males. People of all age groups have been playing or swimming in the contaminated water through diving, water sports, sprinklers, and hoses, which were associated with these infections if water is forced up the nose. A 16-month-old in the U.S. died after exposure to contaminated freshwater at a splash pad in 2023. Nasal rinsing using tap water is an additional risk, which is why health authorities of the government strongly recommend using only distilled or saline solutions for nasal irrigation.
Naegleria fowleri has recently been identified in the drinking water of two towns in south-west Queensland: Augathella, population 300, and Charleville, 3,000 residents. Queensland Health confirmed the presence of organisms after testing water from town water supply systems. Following the discovery, the Murweh Shire Council issued a health notice on August 7, warning visitors and residents of the potential risk.
Although the amoeba was detected in the Charleville and Augathella water supplies, experts emphasize that cooking or drinking with this water is safe. Australian drinking water guidelines recommend that health authorities be immediately consulted if N. fowleri is detected. Disinfection techniques such as chlorination should be applied. Australian town water supply systems were regularly monitored to ensure safety, and the precise cause of the present contamination remains under investigation.
Queensland highlights to reduce the risk of deadly infection by monitoring, providing public awareness, and vigilance. The individuals were advised to take safety precautions during baths or showers and supervise children around hoses or sprinklers by avoiding nasal exposure to tap water. Swimming in oceans and properly chlorinated pools remains safe, as the amoeba cannot survive in chlorinated water or salt water.
Reference: Wright IA. A rare ‘brain-eating amoeba’ has been detected in Queensland water. Can I catch it by drinking tapwater? Or in the shower? The Conversation. Published August 15, 2025. Accessed August 18, 2025. A rare ‘brain-eating amoeba’ has been detected in Queensland water. Can I catch it by drinking tapwater? Or in the shower?
