Parasitic infections can invade practically any part of the body.
Not only can these conditions sometimes be fatal, but they can result in lifelong disability.
Early recognition and prompt treatment are important to reduce both mortality and the frequently catastrophic aftermath of these diseases.
Hilary Allison / Verywell
What symptoms do brain parasites cause?
You may be asymptomatic and still have a parasitic brain infection.
Handwashing and kitchen cleanliness are critical so as not to ingest the eggs.
Ingesting the eggs leads to tapeworm larvae growing in many different human tissues, particularly brain and muscle.
This leads to seizures and more.
It is the eggs that can transmit neurocysticercosis.
What is the most common brain parasite?
Toxoplasmosis
Toxoplasmosisis a parasite infectioncaused by the protozoanToxoplasma gondii.
However, the immune system keeps the parasite in check for most of usand no symptoms develop.
These brain parasites create circularabscesses, which are visible on an MRI.
They can have devastating neurological consequences includingseizures, focal neurological deficits, impaired consciousness, and death.
Cerebral Malaria
Malaria is one of the most serious threats to human life throughout the entire history of humankind.
Over millennia, the disease has killed hundreds of millions of people.
The workings of this parasite are complex, but almost always involve being transmitted by an infected mosquito.
Direct invasion of brain tissue is just one way the parasite wreaks havoc on the human body.
Cerebralmalariacan cause changes in consciousness or seizures.
Without treatment, the disease usually progresses to coma or death.
With treatment, mortality is between 15% and 20%.
Cerebral malaria is most common where malaria is endemic, such as in Africa.
Visitors to such regions can help prevent malaria infection with prophylactic medication and other preventative measures.
The latter is the drug of choice in severe infection.
Like malaria, the parasite is spread by an insect host.
American trypanosomiasis is transmitted by the assassinbug.
A rash may also follow.
The disease is fatal without treatment.
Schistosomiasis
Schistosomiasis, also calledbilharziaorbilharziasis, is resulting from infection with small, flatworms called flukes.
Usually, these small, leaf-shaped worms cause intestinal, liver, kidney, or bladder problems.
Like many parasites, the life cycle of this organism is complex and involves many different stages.
Once in the blood vessels, they can travel through the body.
Roughly 240 million people are infected with schistosomiasis each year.
Most people with this infection feel no symptoms at all.
Sometimes, acute infection can be seen one day after exposure with an itchy rash.
One to two months later, fever, chills, cough, and muscle ache can develop.
Later, as the schistosomes can spread to different organs, various symptoms can occur.
Praziquantel is the treatment of choice.
The parasites which are responsible includeEchinococcus granulosusandEchinococcus multilocularis.
Humans acquire the infection by eating contaminated food.
In the brain, the cysts can cause seizures or elevated intracranial pressure.
In the spinal cord, the cysts can cause spinal cord compression and paralysis.
Cysts may need surgical removal, often with additional medical treatment with a drug such as albendazole or praziquantel.
The infection is relatively uncommon in the United States due to improvements in food preparation.
Larvae invade the wall of the small bowel and develop into adult worms.
Worms then go on to release eggs that grow into cysts in muscles.
When the muscle is ingested by another animal, the cycle continues.
Severe trichinellosis can cause meningitis and encephalitis.
A headache is a common symptom.
The CT scan show small cystic lesions throughout the brain.
Treatment is with albendazole or mebendazole, sometimes combined with prednisone in severe cases.
Paragonimiasis
Paragonimiasisis a parasitic infection with a flatworm which may enter the body through eating undercooked crab or crayfish.
It is rare in the United States, though several cases have been reported in the Midwest.
Most commonly it is found in East Asian countries.
It is contracted from eating undercooked snails, slugs, crabs, or prawns.
The larva of this parasite migrates to the brain causing headaches, nausea, and neck stiffness.
How do you detect brain parasites?
Magnetic resonance imaging (MRI) scans may show signs of parasitic lesions and abscesses.
Additional imaging studies, including CT scans and neuroimaging tests, are also used to help with diagnosis.
Due to symptoms ranging from rashes to seizures, brain parasites should be taken seriously.
Treatment varies, depending on the parasite.
Many can be avoided by using good hygiene, such as frequent hand washing and cooking meat thoroughly.
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