If untreated, ocular sparganosis can lead to blindness.In one case of brain infestation by Spirometra erinaceieuropaei, a man sought treatment for headaches, seizures, memory flashbacks and strange smells. Magnetic resonance imaging (MRI) scans showed a cluster of rings, initially in the right medial temporal lobe, but moving over time to the other side of the brain. The cause was not determined for four years; ultimately a biopsy was performed and a 1 cm-long tapeworm was found and removed. The patient continued to have symptoms. Transmission
The parasite is transmitted to humans in three different ways. First, humans may acquire the infection by drinking water that is contaminated with copepods housing Spirometra larvae. Second, humans may acquire the infection by consuming the raw flesh of one of the second intermediate hosts, such as frogs or snakes. For example, humans consume raw snakes or tadpoles for medicinal purposes in some Asian cultures; if the snakes or tadpoles are infected, the larvae may be transmitted to humans. Third, humans may acquire the infection by placing raw poultices of the second intermediate hosts on open wounds, lesions, or the eyes for medicinal or ritualistic reasons. If the poultice is infected with plerocercoid larvae, the human may become infected. According to Zunt et al., human infection most often occurs following ingestion of infected raw snake, frog, or pig, although contact with infected flesh of an intermediate host can also cause infection. The high prevalence in Korea may be explained by the ingestion of dog meat.
In theory, a pre-operative diagnosis could be made by identification of exposure history and a painful, migratory, subcutaneous nodule. Sparganosis usually presents as a single nodule, while other cestode infections such as cysticercosis typically present as multiple nodules. Preoperative diagnosis, however, is rare.CT and MRI scans are especially useful for diagnosis of cerebral sparganosis, as they reveal lesions in the brain. Through a retrospective analysis of 25 cases of cerebral sparganosis from 2000 to 2006, Song et al. found a number of characteristic signs that could be used in the future to diagnose cerebral sparganosis without performing an excision or tissue biopsy. The most characteristic finding was the "tunnel sign" on MRI images, showing the migrating track of the worm, while the most common finding was multiple conglomerated ring-shaped enhancements, seen as bead-shaped, usually with 3 to 6 rings. These findings led Song et al. to suggest that clinical history, ELISA, and either MRI or CT scans could be sufficient to make a sparganosis diagnosis. These lesions, however, are sometimes mistaken for tuberculosis lesions. In one case cerebral sparganosis was not diagnosed for four years, during which scans showed a cluster of rings moving from the right to the left side of the brain; ultimately the worm was found on biopsy. Prevention
Because sparganosis is a rare infection, public health strategies have not made its prevention a priority. Public health strategies focusing on providing basic access to clean water may help to reduce future sparganosis infections.