Signs and symptoms Taeniasis Taeniasis is infection in the intestines by the adult
T. solium. It generally has mild or
non-specific symptoms. This may include abdominal pain, nausea, diarrhoea and constipation. Such symptoms will arise when the tapeworm has fully developed in the intestine, this would be around eight weeks after the contraction (ingestion of meat containing cysticerci). These symptoms could continue until the tapeworm dies from the course of treatment but otherwise could continue for many years, as long as the worm lives. If untreated it is common that the infections with
T. solium last for approximately 2–3 years. It is possible that infected people may show no symptoms for years. But in humans, infection with the eggs causes serious medical conditions. This is because
T. solium cysticerci have a predilection for the brain. In symptomatic cases, a wide spectrum of symptoms may be expressed, including headaches, dizziness, and seizures. Brain infection by the cysticerci is called neurocysticercosis and is the leading cause of seizures worldwide. In more severe cases,
dementia or
hypertension can occur due to perturbation of the normal circulation of
cerebrospinal fluid. (Any increase in intracranial pressure will result in a corresponding increase in
arterial blood pressure, as the body seeks to maintain circulation to the brain.) The severity of cysticercosis depends on location, size and number of parasite larvae in tissues, as well as the host
immune response. Other symptoms include sensory deficits, involuntary movements, and brain system dysfunction. In children,
ocular cysts are more common than in other parts of the body.
Diagnosis Stool tests commonly include
microbiology testing – the microscopic examination of stools after concentration aims to determine the amount of eggs. Specificity is extremely high for someone with training but sensitivity is quite low because the high variation in the number of eggs in small amounts of sample.
Stool tapeworm antigen detection: Using
ELISA increases the sensitivity of the diagnosis. The downside of this tool is it has high costs, an ELISA reader and reagents are required and trained operators are needed. A 2020 study in Ag-ELISA test on
T. solium cysticercosis in infected pigs and showed 82.7% sensitivity and 86.3% specificity. The study concluded that the test is more reliable in ruling out
T. solium cysticercosis versus confirmation.
Stool PCR: This method can provide a species-specific diagnosis when proglottid material is taken from the stool. This method requires specific facilities, equipment and trained individuals to run the tests. This method has not yet been tested in controlled field trials. Current standard for serologic diagnosis of NCC is the lentil lectin-bound glycoproteins/enzyme-linked immunoelectrotransfer blot (LLGP-EITB). Guidelines for diagnosis and treatment remain difficult for endemic countries, most of them developing with limited resources. Many developing countries diagnosed clinically with imaging.
Prevention The best way to avoid getting tapeworms is to not eat undercooked pork or vegetables contaminated with faeces. Moreover, a high level of sanitation and prevention of faecal contamination of pig feeds also plays a major role in prevention. Infection can be prevented with proper disposal of human faeces around pigs, cooking meat thoroughly or freezing the meat at for 5 days. For human cysticercosis, dirty hands are attributed to be the primary cause, and especially common among food handlers. Therapies primarily include
praziquantel or
niclosamide. There are some concerns over praziquantel administration and serious neurological effects in individuals with neurocysticercosis. A 2025 study attempted to reduce those effects by screening for individuals with neurocysticercosis and treating them with niclosamide instead. Of participants who were treated with praziquantel, 10 experienced serious adverse effects. No participants given niclosamide experienced serious adverse effects.
Treatment Treatment of cysticercosis must be carefully monitored for
inflammatory reactions to the dying worms, especially if they are located in the brain.
Albendazole is commonly given (along with
glucocorticoids to reduce the inflammation). In selected cases, surgery may be required to remove the cysts. In neurocysticercosis, most patients under cysticidal therapy will have significant improvement in seizure control. A combination of praziquantel and albendazole is more effective in treating neurocystercosis. A 2014 double blind randomized control study showed increased parasiticidal effect with albendazole plus praziquantel. A vaccine to prevent cysticercosis in pigs has been studied. The life-cycle of the parasite can be terminated in their intermediate host, pigs, thereby preventing further human infection. The large scale use of this vaccine, however, is still under consideration. During the 1940s, the preferred treatment was oleoresin of
aspidium, which would be introduced into the duodenum via a
Rehfuss tube.
Epidemiology T. solium is found worldwide, but its two distinctive forms rely on eating undercooked pork or on ingesting faeces-contaminated water or food (respectively). Because pig meat is the intermediate source of the intestinal parasite, rotation of the full
life cycle occurs in regions where humans live in close contact with pigs and eat undercooked pork. However, humans can also act as secondary hosts, which is a more pathological, harmful stage triggered by oral contamination. High prevalences are reported among many places with poorer than average water hygiene or even mildly contaminated water especially with a pork-eating heritage such as Latin America, West Africa, Russia, India, Manchuria, and Southeast Asia. In Europe it is most common in pockets of
Slavic countries and among global travelers taking inadequate precautions in eating pork especially. The secondary host form, human cysticercosis, predominates in areas where poor hygiene allows for mild fecal contamination of food, soil, or water supplies. Rates in the United States have shown immigrants from Mexico, Central and South America, and Southeast Asia bear the brunt of cases of cysticercosis caused by the ingestion of microscopic, long-lasting and hardy tapeworm eggs. For example, in 1990 and 1991 four unrelated members of an
Orthodox Jewish community in
New York City developed recurrent seizures and brain lesions, which were found to have been caused by
T. solium. All had housekeepers from Mexico, some of whom were suspected to be the source of the infections. Rates of
T. solium cysticercosis in West Africa are not affected by any religion. Neurocystiscercosis is noted at around one-third of all epilepsy cases in many developing countries. Neurological morbidity and mortality remain high in lower-income countries and high amongst developed countries with high rates of migration. Global prevalence rates remain largely unknown as screening tools, immunological, molecular tests, and neuroimaging are not usually available in many endemic areas. ==See also==