Brain-damaging tapeworm infections on rise in Mumbai this monsoon

Hindustan Times

27-07-2025

Doctors in Mumbai have raised an alarm over the rising number of tapeworm infections during the monsoon, warning that they could lead to deadly brain damage. They specifically pointed to the threat of 'neurocysticercosis', a severe condition caused by ingesting tapeworm eggs through contaminated food or water – risks that increase significantly during the rainy season. Neurocysticercosis is a preventable parasitic infection of the central nervous system, caused by the larval cysts of the pork tapeworm 'Taenia solium'. (Pic used for representation)(Unsplash)
A report by Free Press Journal quoted neurologist Dr Pavan Pai, who said, 'During the monsoon, people frequently neglect fundamental food hygiene, but undercooked pork and inadequately washed vegetables are common carriers of tapeworm larvae.' He explained how the infection progresses: 'Once ingested, these parasites can migrate to the brain, developing into cysts that can trigger seizures, debilitating headaches, and even irreversible neurological harm.'
The risk is further heightened by frequent flooding and poor sanitation during monsoon months, which create ideal conditions for such infections to spread. Pai stressed that children and those with weakened immune systems are particularly vulnerable.
He also issued a crucial warning: 'Never disregard persistent headaches or seizures. Seeking medical attention without delay can be life-saving and prevent potentially devastating consequences.'
What is neurocysticercosis? All you need to know about this brain-affecting tapeworm infection
According to the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC), neurocysticercosis is a preventable parasitic infection of the central nervous system, caused by the larval cysts of the pork tapeworm 'Taenia solium'.
Humans become infected by consuming undercooked pork, contaminated water, or through poor hygiene practices that expose them to tapeworm eggs. The initial intestinal infection, known as taeniasis, occurs when adult tapeworms reside in the gut. If untreated, the infection can progress to cysticercosis, in which larvae invade body tissues such as the muscles, skin, eyes, and most dangerously, the brain.
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When these cysts lodge in the brain, the condition is called neurocysticercosis, the most severe form of the disease. It is a leading cause of seizures worldwide and can lead to irreversible neurological damage or even be fatal. The disease is classified as a Neglected Parasitic Infection, due to its significant impact and lack of awareness among healthcare providers.
Neurocysticercosis is endemic in several regions, including Latin America, Southeast Asia, India, Nepal, China, and parts of Africa.
Symptoms
The clinical symptoms of neurocysticercosis depend on the location of the cysts in the brain, the number of parasites present, and the individual's immune response.
Many people may remain asymptomatic, showing no clear signs of infection.
When symptoms do appear, seizures are the most common, occurring in about 70% of symptomatic patients. These seizures can emerge at any stage of the disease.
Epilepsy is the leading symptom and neurocysticercosis is the primary cause of late-onset seizures in low- and middle-income countries.
Seizures are most commonly linked to parenchymal neurocysticercosis, where the cysts are located within the brain tissue itself. If untreated, seizures may continue and become recurrent, even with anti-seizure medications.
are most commonly linked to parenchymal neurocysticercosis, where the cysts are located within the brain tissue itself. If untreated, seizures may continue and become recurrent, even with anti-seizure medications. Degenerating cysts are often responsible for seizures, as they trigger brain inflammation, swelling, nerve damage, and scarring (gliosis).
The seizures result from both the inflammatory response of the body and the space-occupying effect of the cysts within the brain.
Multiple cysts increase the likelihood of seizures, making the condition more difficult to manage.
Active (living) cysts are typically linked to first-time seizures, while calcified cysts or granulomas—a later stage in the infection—are associated with chronic epilepsy.
Other symptoms of neurocysticercosis include headaches, strokes, neuropsychiatric issues, and a gradual decline in cognitive or motor functions.
Diagnosis
Magnetic Resonance Imaging (MRI) is the preferred diagnostic tool. It is especially effective in detecting intraventricular, subarachnoid, or small parenchymal cysts that may not be clearly visible on other scans.
Computed Tomography (CT) Scan is useful for identifying the different stages of cyst development:
Vesicular stage: Cysts appear non-enhancing (no visible inflammation or Oedema).
Colloidal stage: Cysts become edematous and show contrast enhancement, indicating inflammation.
Calcified stage: Cysts appear as hardened or mineralised lesions, often indicating an inactive or healed stage of infection.
How can you prevent
Neurocysticercosis is more common in regions where the transmission of Taenia solium is likely due to poor sanitation, lack of proper waste disposal, low education levels, and the presence of free-roaming pigs or unregulated pig slaughter practices. The transmission cycle requires both unsanitary conditions and domestic pigs.
As areas undergo urbanization and development, these risk factors decrease, leading to a decline in transmission. However, because neurocysticercosis can take years to manifest, the impact of prevention efforts may not be immediately visible and often requires long-term commitment.
Effective prevention involves improving hygiene and sanitation, raising awareness through education, and enforcing strict standards for pig farming and meat inspection.