Studies sought on amoebic density in waterbodies in Kerala

In view of the recurring cases of amoebic meningoencephalitis in Kerala, experts have sought more studies on the harmful pathogens causing the infection in the water sources, while calling for behavioural changes to deal with the situation.

According to experts, primary amoebic meningoencephalitis and granulomatous amoebic encephalitis are the two types of commonly found infections caused by the free-living amoeba. PAM is caused by the Naegleria fowleri species, commonly termed as “brain-eating amoeba” as it destroys the brain tissue leading to the death of the patient. GAE is caused by species such as Acanthamoeba and Balamuthia mandrillaris. The presence of these species has been detected in Kerala’s environment already.

T.S. Anish, Professor, Community Medicine, and nodal officer for the Kozhikode-based Kerala One Health Centre for Nipah Research and Resilience, says it is important to know the density of amoebae in the water sources. “Amoeba is ubiquitous in the atmosphere. There is a need to find out the seasons during which their density increases. Also, whether factors such as sewage discharge and the resulting water contamination are contributing to it,” he says.

Dr. Anish claims the link between climate change and these infections need not be a linear one. “In the past decade or so, due to the rise in temperature, the presence of these amoeba has increased in our atmosphere. Even a small change in the atmospheric equilibrium will lead to significant outcomes in terms of the infections. From the available data, we can see that these infections start getting reported by February-end, reach a peak in the summer months, remain high in the monsoon months, and the cases decline by October when the ambient temperature drops,” he says.

Dr. Anish says that the districts that reported a high number of Hepatitis ‘A’ cases have had amoebic meningoencephalitis cases too showing a link between the infections and water contamination.

K.K. Purushothaman, former Professor, Government Medical College, Thrissur, suggests that behavioural changes and creating awareness on chlorination could be crucial in dealing with the situation. “The stress should be on the protection of the nose through which amoeba enters the body. Also, chlorination should be done periodically in wells and water tanks. The government should ensure that bleaching powder is made available to the people in required quantity,” he adds.

Meanwhile, asked about the reporting of relatively high number of such infections in recent months, another government doctor, who did not wish to be named, says that “diagnostic sensitivity” is now high in Kerala.

“At present, we have almost a 100% chance of detecting the presence of an amoeba in an infected person. If the presence of a free-living organism is found in the cerebrospinal fluid of a person through a microscopic test, we are terming it amoebic meningoencephalitis. The medical treatment is started even without a PCR reaction confirming the presence of the organism. Because of this, many patients are getting cured of this infection, whose mortality rate is normally above 97%,” he adds.