Taeniasis/cysticercosis (Tape Worm Infections – Fish)
Taeniasis due to T. solium or T. saginata is usually characterized by mild and non-specific symptoms. Abdominal pain, nausea, diarrhoea or constipation might arise, 6-8 weeks after ingestion of the cysticerci when the tapeworms become fully developed.
These symptoms may continue until the tapeworm dies following treatment (otherwise it may live many years).
In the case of cysticercosis due to T. solium, the incubation period is variable, and infected people may remain asymptomatic for years.
In some endemic regions (in particular Asia), infected people may develop visible or palpable nodules (a small bump or node which is solid that can be detected by touch) beneath the skin (subcutaneous).
When cysts are recognized by the host following spontaneous degeneration or after treatment, an inflammatory reaction may occur.
Neurocysticercosis is associated with a variety of symptoms and signs depending on the number, size, stage and location of the pathological changes as well as the host’s immune response and the parasite’s genotype, but it can also be clinically asymptomatic. Symptoms may include chronic headaches, blindness, seizures (epilepsy if they are recurrent), hydrocephalus, meningitis, dementia and symptoms caused by lesions occupying spaces of the central nervous system.
The diagnosis of neurocysticercosis usually requires MRI or CT brain scans. Blood tests may be useful to help diagnose an infection, but they may not always be positive in light infections.
Taenaisis can be treated with praziquantel (5-10 mg/kg, single-administration) or niclosamide (adults and children over 6 years: 2 g, single-administration after a light breakfast, followed after 2 hours by a laxative; children aged 2-6 years: 1 g; children under 2 years: 500 mg).
Currently there are no standard treatment guidelines for neurocysticercosis and treatment has to be tailored to the individual case. Since the destruction of cysts may lead to an inflammatory response, treatment of active disease may include long courses with praziquantel and/or albendazole, as well as supporting therapy with corticosteroids and/or anti-epileptic drugs, and possibly surgery. The dosage and the duration of treatment can vary greatly and depend mainly on the number, size, location and developmental stage of the cysts, their surrounding inflammatory edema, acuteness and severity of clinical symptoms or signs.