Doctors in the United States discovered that the strong and frequent migraines suffered by a patient were caused by the presence of larvae of the tapeworm parasite in the brain.
The 52-year-old, whose identity has not been revealed, visited his doctor in Florida after his migraines worsened and his regular pills stopped working.
When performing tomography scans, doctors found the presence of numerous cysts in his brain which, as they later confirmed with subsequent studies, were actually tapeworm larvae that had settled in his brain and were the cause of an infection known as neurocysticercosis.
This infection is caused by the larvae of the parasite Taenia solium (T.solium), also known as the pork tapeworm.
Doctors believe the man first contracted an intestinal tapeworm from eating undercooked pork.
Eating undercooked pork cannot directly cause neurocysticercosis in a person.
Experts believe that the patient first contracted the intestinal tapeworm and then, after improper hand washing, ingested the eggs that the tapeworm from his intestine had excreted in his feces, causing neurocysticercosis.
Writing about the case in the scientific journal American Journal of Case Reportsdoctors indicated that “one can only speculate” that the man’s cysticercosis was transmitted through self-infection.
The patient responded to antiparasitic and anti-inflammatory medications and made a full recovery.
“Bad hand washing”
According to the US Centers for Disease Control and Prevention (CDC), tapeworm larvae “enter tissues such as muscles and the brain and form cysts. When cysts are found in the brain, the condition is called neurocysticercosis.”
“People get cysticercosis when they swallow T.solium eggs that are passed in the feces of a human with a tapeworm.”says the CDC.
“Humans swallow the eggs when they eat contaminated food or put contaminated fingers in their mouth.”
“Someone with a tapeworm can infect themselves (autoinfection)” and other family members,” they add.
Experts say eating undercooked pork cannot cause neurocysticercosis, and the condition is also not common in the U.S., where pork undergoes rigorous testing.
The highest rates of this condition are found in parts of Latin America, Asia and Africaand is more common in rural areas where pigs – the carriers of the pork tapeworm – are allowed to roam freely and hygiene and food safety practices are poor.
People are at greater risk of contracting these types of infections if they wash their hands poorly or if they ingest contaminated water or food.
The authors of the report concluded: “It is very rare for patients to contract neurocysticercosis outside of classic exposures or traveland such cases in the United States were thought to be nonexistent.”
They say the case highlights the risk of “consumption of undercooked pork” and subsequent self-infection.
“Historically, it is very unusual to find infected pork in the United States and our case may have implications for public health,” the report concludes.
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