|
|
Tapeworm and the brain
Prof. H. Foyaca-Sibat, University of Transkei
A neurologist based in the former Transkei region of South Africa profiles a
seldom heard of neurological ailment which affects more than 50 million people
world-wide. The catch is not knowing you may have it. In southern Africa where
many are living with HIV, a bleak picture is painted.
Neurocysticercosis(NCC) is the most common parasitic infection of the brain
affecting more than 50 million people all over the world. NCC is caused by
infection of the larvae of the pig tapeworm Taenia solium(TS). Pigs
become  infected when they ingest contaminated human
faeces.
If someone ingests diseased (measly) pork meat containing larva forms of
this tapeworm or ingests its eggs when eating contaminated foods, the parasite
fins its way to the small intestine where they become mature. From here the
parasite spreads to the brain to form of cystic lesions, also affecting the
eyes, muscles or spinal cord.
This parasite can live for years sometimes for entire life-times in the
brains of humans who can be free of symptoms, particularly so in HIV infected
patients. In HIV patients where the immune system is compromised the parasite
remains alive far longer in the brain, but its is a two way street.
Neurocysticercosis debilitates the body's defense system and these patients
become much more susceptible to get infection and are more prone to develop
AIDS. In HIV-positive patients with NCC, epilepsy, epileptic attacks and
seizures are the symptoms most commonly observed.
In non-HIV patients the parasite symptoms differ from country to country but
in general the most common symptoms include epileptic attacks , headaches,
visual and skin problems, and psychiatric manifestations. Any person living,
visiting or in close contact with persons from endemic areas such as Latin
American, Asian, or African countries could be a candidate for  NCC. If you are
in that group and you developed epilepsy later in your life (though younger ages
are not an exclusion criteria) you could be a candidate. Diagnosis by a
health professional could rule out NCC as a cause. Radiographic tests such as
Computer Tomography (CT Scan) of the brain is the best confirmatory test, as it
identifies most of the cystic lesions and also the head of the parasites (see
image to the right). The CT Scan test is available in most cities in South Africa and for
patients  requiring special care the New Nelson Mandela Academic Hospital a
National Reference Center is an option. Alternative ways do exist in case
CT Scan is not available.
The medication of choice for infection of the brain by this tapeworm is
praziquantel or albendazol taken with steroids under medical supervision. These
anti-parasitic medications kill parasites in all stages of their development in
the human brain, eyes or muscles. Most patients respond very well to one-day
treatments with praziquantel. However, for people living in endemic areas who
remain susceptible to re-infection, periodical treatment is necessary.
The good news is that after the treatment the damage to the brain is 100 %
reversible in most cases and only a few require intensive medical attention.
National figures for NCC remain unknown. NCC is a disease of poverty and
underdevelopment and its dissemination is permanent in areas where the
population have a limited or non-existent access to primary health care
attention, health education, proper access to toilet facilities, proper refuse
disposal, safe and clean water, electricity, employment, and money. The former
Transkei areas of Southern Africa are perhaps hardest hit. According to Prof
Foyaca patients are treated for NCC with young children more so than adults.
While this situation persists the number of infected immigrants to developed areas will
continue increasing. Patients diagnosed in Soweto, Cape Town, and other
places are migrants from impoverished regions of Southern Africa.
Although we can't expect radical changes we may contribute to reduce the risks
to this disease by:
- spreading this information
- encouraging all people with a high suspicion of NCC to be seen by health
professionals,
- educating our population towards better personal hygiene, hygienic food
preparation,
- freezing suspected pork meat when it is possible or simply overcooking it ,
- educating people to limit access of pigs to human feces.
More Information:
Prof. H. Foyaca-Sibat is with the Department of Neurology. Division of Medicine. Faculty of Health Sciences.
University of Transkei. Private Bag X1 Umtata 5100 South Africa.
Email: foyaca@intekom.co.za
|
