1 SummaryAn epidemiological survey of taeniasis/cysticercosis was carried out in one semi-urban and two urban villages in three districts in Bali, Indonesia in 2002 and. A total of 398 local people from 247 families were diagnosed by anamnesis and clinical examinations, and 60 residents were suspected to be taeniasis carriers. Among 60 suspected carriers, 56 persons expelled a total of 61 taeniid adult worms after praziquantel treatment. From 398 residents, 252 stool samples were available for analysis of taeniid eggs, copro-antigens or copro-DNA for identification of taeniid species, and 311 serum samples were available for detection of antibodies against Taenia solium cysticercosis. Taeniasis prevalences were highly variable among three villages (1.1-27.5%) and only one cysticercosis due to T. solium infection was detected. All expelled tapeworms were confirmed to be Taenia saginata by mitochondrial DNA analysis. There was no Taenia asiatica human case in Bali. Case control analysis of 106 families chosen at random from 179 families in 2004 and another 106 families from non-endemic areas revealed that risk factors of T. saginata taeniasis for families were the level of education (p < 0.01), the consumption of beef lawar (p < 0.01) and the source of lawar (p < 0.01).

IntroductionTaeniasis/cysticercosis, caused by the pork tapeworm, Taenia solium, is a parasitic zoonosis found primarily in countries where pigs are raised and meat inspection is lacking [1,2]. The potential for a tapeworm carrier to infect another individual (or themselves via autoinfection), resulting in cysticercosis or neurocysticercosis (NCC), is a risk not only in endemic areas, but also in areas with immigrants from endemic countries [1,[3][4][5]]. An example of such an outbreak occurred in an Orthodox Jewish community in New York City when family members were infected by a domestic employee from a T. solium endemic country [6]. Such NCC outbreaks have occurred in other developed countries, including countries in the Middle East where people do not consume pork [4,5,[7][8][9][10][11][12][13].In Asia, there are three Taenia tapeworms that infect humans; T. solium, Taenia saginata and Taenia asiatica [4,5,[14][15][16][17][18][19][20][21][22][23][24]. Although adult T. solium worms with scoleces are easily differentiated morphologically from other taeniids, it is almost impossible to differentiate adult T. asiatica and T. saginata [5,22,25,26]. Therefore, molecular differentiation is often required to correctly identify the infecting species [27]. Recent studies have also reported hybrids of T. saginata and T. asiatica in Thailand and China [5,25,[28][29][30][31][32]. This makes mitochondrial and nuclear gene analyses even more important for the differentiation of T. saginata, T. asiatica, and hybrids of these two species [30][31][32].In Indonesia, T. solium, T. saginata and T. asiatica are distributed according to livestock rearing and local food consumption practices [33][34][35][36][37][38][39][40]. Both T. saginata and T. solium have been confirmed from the island of Bali, where the local inhabitants are known to eat dishes that contain undercooked beef and pork, such as the traditional dish Lawar. NCC was considered endemic on Bali more than 20 years ago [41,42]. However, education programs aimed at keeping pigs indoors to prevent access to human faeces and the introduction of improved sanitation systems and practices have substantially reduced the prevalence of NCC during the past 2 decades [35,37,43]. Nevertheless, there are still sporadic NCC cases identified on Bali [40,[42][43][44][45]. Case ReportFieldwork conducted on Bali from 2002-2007 resulted in the identification of 69 taeniasis carriers who were treated with a single dose of praziquantel (PZQ) at 15 mg/kg body weight (Table 1). All worms were confirmed to be T. saginata by multiplex PCR [36]. In August 2007, a 47-year-old male taeniasis carrier from the Gianyar district suffered a single tonic-clonic seizure within a few hours of PZQ administration. The patient was subsequently admitted to the Sanglah Hospital in Denpasar. A computed tomography (CT) scan revealed one viable cystic lesion and one calcified lesion in the right frontal lobe of the brain. At this time, serology (ELISA) was also carried out using partially purified antigens by c...