What began as a backpacking adventure through India turned into a years-long medical nightmare for a British woman, whose shocking diagnosis has drawn attention to a little-known parasitic brain infection that can remain hidden for years. 

Lowri Denman, a 42-year-old media professional from Cardiff, has revealed that she was diagnosed with neurocysticercosis after doctors discovered 38 live parasites embedded in her brain. Her experience has highlighted how the condition can develop long after the initial infection, with symptoms appearing only when the parasites begin affecting the brain.

Despite taking precautions during her travels in 2007 by eating only vegetarian food to reduce the risk of food-borne illnesses, Denman unknowingly consumed microscopic tapeworm eggs. Years later, she would learn that avoiding meat alone does not eliminate the risk of this particular infection.

Shocking diagnosis years after travelling

Denman's health ordeal did not begin immediately after her trip. Four years later, she unexpectedly passed a tapeworm measuring about a metre in length. Although she was treated and initially reassured that the problem had been resolved, her condition soon took a more serious turn.

Within months, she developed intense headaches before suffering a severe tonic-clonic seizure that temporarily affected her ability to speak. Brain imaging, including CT and MRI scans, eventually revealed the cause, dozens of parasitic cysts lodged deep within her brain tissue.

Doctors diagnosed her with neurocysticercosis, a potentially serious infection of the brain caused by the larval stage of the pork tapeworm.

What is neurocysticercosis?

Neurocysticercosis is a disease that affects the brain and central nervous system after a person ingests microscopic eggs of the pork tapeworm, Taenia solium. Once inside the digestive tract, the eggs hatch into larvae that can enter the bloodstream and travel to different parts of the body, including the brain, where they develop into fluid-filled cysts.

The condition is recognised as one of the leading preventable causes of acquired epilepsy in many parts of the world where the parasite remains common.

One of the most concerning aspects of the disease is that the cysts can remain inactive for months or even years before triggering symptoms. In many cases, inflammation develops only when the parasites begin to die or interfere with surrounding brain tissue.

You don't have to eat pork to get the disease

One of the biggest misconceptions surrounding neurocysticercosis is that it is contracted by eating undercooked pork. Medical experts say that is not how the neurological form of the disease develops.

Eating infected pork can result in an intestinal tapeworm infection. Neurocysticercosis, however, occurs when a person swallows microscopic tapeworm eggs through food, drinking water or contaminated surfaces. This can happen if food has been handled by someone carrying the tapeworm who has not practised proper hand hygiene, or if produce has been exposed to contaminated water.

After entering the body, the eggs hatch into larvae, penetrate the intestinal wall and spread through the bloodstream before becoming lodged in the brain.

Symptoms may take years to appear

A major challenge with neurocysticercosis is that symptoms often develop long after the initial infection, making diagnosis difficult.

Common symptoms include:

  • Seizures
  • Persistent or severe headaches
  • Difficulty speaking
  • Dizziness
  • Problems with memory or concentration
  • Muscle weakness
  • Vision changes
  • Confusion and other neurological symptoms

For many patients, seizures are the first indication that something is seriously wrong and often lead to further neurological investigations.

How is neurocysticercosis diagnosed?

Doctors typically diagnose neurocysticercosis using brain imaging tests such as CT and MRI scans, supported by a patient's medical history and laboratory investigations.

According to the World Health Organization (WHO), neurocysticercosis remains one of the leading preventable causes of adult-onset epilepsy globally, particularly in regions where sanitation is poor and the parasite is more widespread.

Treatment depends on the severity

Treatment is tailored to each patient because the number, location and stage of the cysts vary considerably.

Management may include anti-parasitic medicines to destroy the larvae, corticosteroids to control inflammation, anti-seizure medications for epilepsy and, in some cases, surgery if the cysts cause significant complications.

Doctors closely monitor treatment because killing the parasites can temporarily increase inflammation in the brain before the patient's condition begins to improve.

Now in her 40s, Denman says she has recovered significantly and is using her experience to raise awareness about tropical diseases among international travellers.