High temperature sparks surge in fatal brain infections in Kerala; experts sound alarm

KOZHIKODE: Rising temperature has sparked a fresh public health concern in the state, with six deaths reported in the past month from amoebic meningitis -- a rare but deadly brain infection caused by Naegleria fowleri. The fatalities have prompted health officials and researchers to sound the alarm over water safety and climate-linked health risks. Commonly known as the brain-eating amoeba, Naegleria fowleri flourishes in warm, untreated freshwater sources such as ponds, lakes, rivers, and even inadequately maintained swimming pools. Warmer conditions create the perfect breeding ground for the pathogen, increasing the chances of human exposure during recreational water activities. Amoebic infections are strongly tied to the summer season. The organism becomes more active as water warms, which is why swimming, diving, or immersing the head in untreated freshwater is particularly dangerous now, a senior epidemiologist with the state health department said. Infection occurs when contaminated water enters through the nose, allowing the amoeba to migrate along the olfactory nerve into the brain. Once there, it triggers primary amoebic meningoencephalitis (PAM), a disease that progresses at alarming speed. Symptoms -- ranging from severe headache and fever to seizures and coma -- can appear within days, leaving little time for medical intervention. According to the study Naegleria Infection and Primary Amebic Meningoencephalitis, published by the National Library of Medicine, under the National Institutes of Health in the United States, The life cycle of N fowleri consists of three stages: trophozoites, flagellates, and cysts. The trophozoite stage is the reproductive and invasive form responsible for human infection. As a thermophilic organism, it is most active during the warm summer when human exposure is more likely. Trophozoites are long and slender, approximately 22 micrometres (m) long, equipped with pseudopodia for movement and bacterial ingestion, and capable of forming large colonies. According to Najwa Pervin and Vidya Sundareshan who conducted the research, Of the 47 known species of Naegleria, only N fowleri causes PAM, which is a rare but aggressive infection that typically leads to death within three to seven days. Once inside, N fowleri migrates to the central nervous system (CNS) via the olfactory nerves and cribriform plate, leading to severe and nearly always fatal infection. N fowleri infections are more prevalent in healthy, immunocompetent young males during the summer when water temperatures are high and people engage in outdoor water activities. They further pointed out that to prevent N fowleri infection, individuals should avoid activities that introduce freshwater into the nasal passages, especially during summer. When using non-sterile tap water or swimming in freshwater bodies or poorly chlorinated pools, it is important to keep the head above water or use nose clips. Naegleria destroys brain tissue rapidly, and the window for saving a patient is incredibly narrow, explained Dr Sunitha, an infectious disease expert. The connection between climate change and amoebic infections is not straightforward but is becoming increasingly evident. In the past decade, warmer temperatures have encouraged the presence of free-living amoebae in our surroundings. Even a minor shift in atmospheric equilibrium can trigger major health consequences, she noted. Rising temperature is no longer just an environmental concern -- its a direct public health threat, the senior epidemiologist senior warned, adding that, At the same time, the states capacity to diagnose the disease at the earliest is helping save lives. Kerala has the facilities to run microscopic tests to identify the amoeba in an infected patients cerebrospinal fluid. This is a blessing.