Brain-eating amoeba in Kerala: How it spreads, early signs and prevention

Business Standard

11 hours ago

In Kerala's Kozhikode district, a nine-year-old girl died recently, while a three-month-old baby and a 40-year-old man are currently battling for their lives. The reason - Primary Amoebic Meningoencephalitis (PAM), a rare but nearly fatal brain infection.
District Medical Officer KK Rajaram clarified on Monday that though the mortality of this rare infection is extremely high, it does not spread from person to person. However, with no single effective treatment available, awareness and prevention remain the key to avoid further infection.
What is PAM and how does it occur?
PAM, or primary amoebic meningoencephalitis, is a swift and deadly brain infection caused by the free-living amoeba Naegleria fowleri, often dubbed the 'brain-eating amoeba'.
"Naegleria fowleri exists naturally in warm freshwater environments like lakes, rivers, ponds, and inadequately chlorinated or untreated swimming pools. It develops best in water temperatures ranging from 25 degrees Celsius to 40 degrees Celsius, hence making tropical and subtropical areas more susceptible," said Dr Girishkumar Soni, who works with the Department of Neurology at Lilavati Hospital Mumbai.
"The amoeba infects a person when infected water enters the nostrils, commonly while swimming, diving, or nasally rinsing with unsterilized water. It travels from the nasal cavity along the olfactory nerve to the brain, causing intense brain tissue inflammation. Infection is not through ingestion of infected water but is purely associated with nasal exposure," he added.
What are the symptoms?
"Since its discovery, only a few hundred cases of the disease have been documented, making it incredibly rare. Treatment is very challenging and it has a very high mortality rate, with over 90% of infected people dying. The younger population, including children and young adults, are more prone to this illness," said Dr Charudatt Vaity, director-critical care, Fortis Hospital Mulund.
Symptoms of PAM include -
Intense headache
High fever
Nausea, and vomiting
Nasal discharge
"These may then develop into more serious neurological symptoms like seizures, increased drowsiness, and altered behaviour. The individual may eventually go into a deep coma, which could result in death," added Dr Vaity.
Challenges in treating PAM
According to Dr Vaity, the main challenge in the treatment of PAM is that amoeba causes severe destruction of brain tissue and the majority of parasite medications are unable to effectively enter the brain.
"The primary treatment tried is the antifungal Amphotericin B, which is occasionally taken with Rifampicin, a medication mainly used to treat tuberculosis. Although they are not proven treatments, they can be tried as a last resort. The absence of a single effective medication is the cause of the high death rate," he explained.
"A variety of drugs, including amphotericin B, miltefosine, azithromycin, rifampicin, and fluconazole, have been administered in combination. Intravenous and intrathecal administration of amphotericin B is the treatment of choice," said Dr Soni.
Diagnosis is frequently delayed due to the unfamiliarity of the disease. "The other big challenge is the time for diagnosis—when the disease is rare and has similar early symptoms to viral meningitis, there can be a significant delay in the start of specific therapy for the infection," said Dr Subhajit Pal, neurologist at the Calcutta Medical Research Institute.
Role of climate change
"Increased temperature and erratically timed rainfall have raised the incidence of Naegleria fowleri in freshwater. Stagnant warm water with inadequate chlorination is a favourable setting for the amoeba," said Dr Soni.
Adding to the point, Dr Vaity said, "Warm, tropical climates like India's are favourable for the amoeba, increasing the risk of infection. Proper water management is very important in such an environment. Public or municipal swimming pools must be cleaned and maintained regularly, as this is where the illness can originate."
"Good water treatment, sanitation, and safe recreational water practices are important to prevent risks of PAM," added Dr Pal.
How are health authorities responding?
The Kerala health department has escalated preventive measures:
Chlorinating local wells and water bodies
Issuing public advisories to avoid swimming or bathing in untreated freshwater
Encouraging use of nose clips for swimming
Implementing fever surveillance in affected areas
Conducting water testing to prevent further exposure
How can individuals and families stay safe?
To reduce the risk of infection:
Avoid swimming or bathing in warm, stagnant freshwater such as ponds or unchlorinated pools.
Use well-maintained and properly chlorinated pools or water features, and nose clips.
For nasal rinsing or ablutions, use only boiled (and cooled), distilled, or sterile water.