Kerala’s health department has sounded an alert in Kozhikode district after three back-to-back cases of the rare but deadly brain infection primary amoebic meningoencephalitis (PAM) were reported.

One of the victims, a nine-year-old girl, died on August 14, while a three-month-old baby and another patient continue to battle for their lives. The health department is still investigating the possible sources of infection, most likely ponds or other freshwater bodies in the region. This year alone, Kerala has reported eight confirmed cases of PAM and two deaths. 

When was the first case reported in India?

India’s first case of PAM was documented in 1971, while Kerala recorded its first case in 2016. For years, the infections were sporadic, with only eight cases between 2016 and 2023. But last year, numbers spiked sharply, with 36 confirmed cases and nine deaths.  

Globally, PAM has a fatality rate of 97 per cent, yet Kerala has managed to reduce it to around 25 per cent through early detection and interventions. In July 2024, a 14-year-old boy from Kozhikode became the first Indian—and only the 11th person worldwide—to survive the disease, offering a rare glimmer of hope. 

What is ‘Brain-Eating Amoeba’?

The infection is caused by Naegleria fowleri, a free-living microscopic amoeba often dubbed the “brain-eating amoeba.” This organism thrives in warm freshwater and moist soil, growing best in high temperatures up to 46°C.

It has also been detected in inadequately chlorinated swimming pools, tap water, industrial wastewater, and even household water heaters. The amoeba becomes dangerous when it enters the body through the nose, travelling to the brain, where it triggers a severe and often fatal inflammation that destroys brain tissue. 

How does the infection happen?

The infection route is unusually specific. Naegleria fowleri cannot cause illness if swallowed; it becomes deadly only when contaminated water enters the body through the nose.

Activities like swimming, diving, or dunking the head in lakes, ponds, or poorly maintained pools increase the risk.  

Once in the nasal cavity, the amoeba moves along the olfactory nerve and crosses into the brain. There, it causes primary amoebic meningoencephalitis, leading to swelling, tissue destruction and rapid neurological decline. It does not spread from person to person and is not transmitted through water vapour or mist. 

What symptoms should raise an alarm? 

The signs of infection typically appear within one to nine days of exposure and progress with alarming speed. Early symptoms resemble meningitis and include high fever, severe headache, nausea and vomiting. As the disease advances, patients may develop a stiff neck, mental confusion, sensitivity to light, tremors, loss of balance and even hallucinations. In most cases, the illness progresses to coma and death within five to eighteen days after the first symptoms appear.  

Is there a cure—and how can you stay safe?

Treatment options for PAM remain extremely limited, largely because the disease progresses so quickly and is often diagnosed late. Experimental drug combinations, particularly antifungals and antibiotics, have been tried with varying degrees of success. Survival, however, is exceptionally rare, with fewer than 20 known cases worldwide. Kerala’s recent success in treating a 14-year-old boy marked a significant breakthrough, yet prevention continues to be the only reliable safeguard against the disease. 

“Water bodies should be cleaned regularly, and swimming pools must be chlorinated, maintained, and kept hygienic as per the guidelines. People need to be extra cautious during water-related activities—always use a nose clip. Even babies must be protected; contaminated water should never enter their nose, so it is important to always filter or boil the water,” said Dr Anuradha T.C. Nambiar, Assistant Director, Department of Health and Family Welfare, Government of Kerala. 

Dr Rajaram KK, District Medical Officer of Kozhikode, echoed the concern: “We have not yet arrived at a definite conclusion regarding the cause. Kerala has a population density comparable to Delhi, and there may be contamination of water sources from different areas, but a conclusive study has not been undertaken. What we do know is that cases are being reported from different parts of the state. Though they remain occasional, they are alarming.” 

He explained that the infection is caused by free-living amoebas that usually enter the body through the nose. “They are most often found in stagnant water—ponds, slow-moving rivers, or even in water where animals like buffaloes bathe. In recent times, traces have also been detected in some well-water samples,” he said. 

According to Dr Rajaram, the risk arises not from drinking water but from contaminated water entering the nasal cavity. “That is why we are stressing preventive measures. People should avoid bathing in ponds for the time being. Even swimming pools can pose a risk if not maintained properly. Ideally, pools should be chlorinated weekly, scrubbed thoroughly before draining, and allowed to dry under sunlight before being refilled.” 

The DMO further noted that the health department will provide guidance for chlorinating wells. “People with nasal surgeries or ear discharge, especially those with a damaged eardrum, should strictly avoid bathing in natural water sources,” he cautioned. 

Calling PAM an extremely rare but highly fatal infection with a 95–100% mortality rate, Dr Rajaram said doctors are adhering to the treatment protocol. “Unfortunately, the two current patients remain in the same critical condition as when they were admitted,” he added. 

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