THIRUVANANTHAPURAM: The Nipah outbreak served as a wake-up call for Kerala, prompting the state to intensify its focus on cases of reported brain fever, some of which turned out to be deadly amoebic infections. While the health department was virtually unprepared for the 2018 Nipah outbreak, the 2023 flare-up -- marked by human-to-human transmission -- signalled a significant shift in approach.
The first case of amoebic meningoencephalitis (AME) was reported in 2016, but it wasn’t until after 2023 that clinicians began to suspect AME among brain fever (encephalitis) patients. This led to the development of a formal treatment protocol in 2024.
Encephalitis, the inflammation of the brain due to infection, is a common feature in several diseases, including Nipah and AME.
“We first developed the capacity to identify and treat Nipah patients promptly in 2023. But to truly understand Nipah, we had to understand encephalitis better. That led us to investigate all encephalitis cases, which in turn shifted our focus to non-viral pathogens, including amoeba,” explained Dr T S Anish, professor and nodal officer at the Kerala One Health Centre for Nipah Research and Resilience, Government Medical College and Hospital, Kozhikode.
Globally, fewer than 500 AME cases have been documented since 1962, with a staggering 95% fatality rate. In contrast, Kerala reported 39 cases in 2024 and 71 cases with 19 deaths in 2025 – a mortality rate of approximately 23-24%.
Despite the spike in cases, health experts in Kerala have worked to dispel public confusion and misinformation. “Reducing the death rate has been a significant achievement for Kerala,” said Dr Purushothaman Kuzhikkathukandiyil, professor of paediatrics at MES Medical College, Malappuram.
“This success is due to a combination of factors, such as early identification and the timely use of drugs such as Miltefosine.”
He added, “The Nipah outbreak helped establish a robust surveillance system and
laboratories. If not for the awareness among clinicians who insisted on testing cerebrospinal fluid (CSF) for a wet-mounted test within 24 hours, AME cases could have easily been misdiagnosed as biogenic encephalitis, which closely resembles AME. Other states have reported such misdiagnoses.”
Meanwhile, Health Minister Veena George stated that Kerala has begun taking proactive measures against AME through its One Health approach, making it the first state in India to do so.