Adult tapeworms cause an intestinal infection called Taeniasis, of which Taenia solium (pork tapeworm) has a major impact on human health. Tapeworm eggs pass with the faeces and are infective for pigs. Humans can become infected by ingesting raw or undercooked, infected pork. Infection can result in two distinct conditions: taeniasis and cysticercosis. While the adult tapeworm in the human intestine (taeniasis) does not have major health impacts cysticercosis can result in devastating effects on human health. The larvae may develop in the muscles, skin, eyes and the central nervous system. When cysts develop in the brain, the condition is referred to as neurocysticercosis. Symptoms include severe headache, blindness, convulsions, and epileptic seizures, and can be fatal. To prevent, control and possibly eliminate Taenia solium, proper public health interventions with an approach spanning veterinary, human health, and environmental sectors are required.

Cysticercosis is a focal disease, affecting the poorest communities in which basic sanitation is deficient and pigs roam free. One of the first steps to control the disease is to identify those communities or endemic areas where control measures need to be implemented. WHO is assisting countries by providing protocols for mapping (identifying the endemic or high-risk areas), as well as assisting countries such as Cambodia in training diagnostic techniques that can be used for mapping.

Taeniasis is usually characterized by mild and non-specific symptoms associated with an intestinal infection (abdominal pain, nausea, diarrhea, etc.). These symptoms may continue until the tapeworm dies following treatment, otherwise, it may live for years.

For cysticercosis, the incubation period is variable, and infected people may remain asymptomatic for years. In some endemic regions, infected people may develop visible or palpable nodules (a small solid bump or node which is solid that can be detected by touch) beneath the skin.

Neurocysticercosis is associated with a variety of signs and symptoms 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 treatment of taeniasis by Taenia solium is important to prevent neurocysticercosis and as a tool to assist in controlling or stopping the parasite transmission cycle. The treatment can be done on an individual bases, or as mass drug administration depending on the local circumstances and the control approaches being implemented. Taeniasis can be treated using anthelmintics (Praziquantel, Niclosamide, Albendazole)

In neurocysticercosis, since the destruction of cysts may lead to an inflammatory response, specialized treatment of active disease is required and may include long courses with high doses of anthelmintic, 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.