Kolkata: Institute of Neurosciences Kolkata (INK) has detected six cases within a year of an infection where a rare amoeba eats into the human brain. One patient is still under treatment. Doctors wondered if immunological changes due to Covid-19 have pushed this amoeba to infect humans more often.
The brain-eating amoeba causes a condition called Primary Amoebic Meningoencephalitis (PAM) with 90% mortality.Kolkata reported the first PAM case in 2015, in which a teenager succumbed during treatment. Another case was reported in SSKM this Jan, which TOI reported. Now, there have been six cases in a single hospital in a span of a year.
“In 2023, we got two cases which we reported in the Indian Academy of Neurology and we detected four in the past few months. We need to have an epidemiological study to search for the reason behind the spurt,” said neurologist A Shobhana, senior consultant in critical care, stroke, and tropical neurology, INK.
While immuno-compromised individuals are susceptible to infection, some patients at the Park Circus hospital were seemingly healthy ones. According to experts, there are four genera of such amoebas: Naegleria, Acanthamoeba, Balamuthia and Sappinia, all of which cause central nervous system (CNS) infections. Transmission to humans occurs though inhalation of infested water. Although risk of infections has been reported to be high in recreational water sports, the Indian subcontinent has reported cases in people not involved in such activities as well. “In 20% cases, no clear source of infection may be detected. Out of the six cases in our hospital, only one had exposure to a swimming pool,” Shobhana said.
Treatment includes administering medicines inside the fluid-containing areas in the brain. Some may require surgery for complications, like hydrocephalus. While fever, headache, vomiting, alteration in sensorium and convulsions are common manifestations, classic symptoms may be absent, especially in the elderly, who may exhibit change in behaviour, memory loss or locomotor problems.