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Diphyllobothriasis latum is an intestinal parasitosis caused by the ingestion of mostly raw fresh-water fish containing plerocercoids of Diphyllobothrium latum. We report an 8-year-old boy who came to our hospital with the complaint of a tapeworm hanging from the anus after defecation. The other symptom was mild abdominal cramping for a period of 1 year. The laboratory examination did not reveal anemia or vitamin B12 deficiency. Examination of gravid proglottids with rosette-like central uterus and typically operculated eggs of D. latum confirmed the diagnosis. The morphologic characters of proglottids and eggs size are compatible with D. latum. The patient had a history of eating uncooked fish for 1 year. Salmonids may be the infection source. He was treated with two doses of praziquantel and passed about 183 cm in length of all proglottids. There is a high prevalence of diphyllobothriasis latum in the northern temperate areas, but it is very rare in children. This patient is the first child case reported in Taiwan.

In Taiwan, Angiostrongylus cantonensis infection has been reported in foreign laborers who had consumed raw Ampullarium canaliculatus snails. This study analyzed three foreign laborers who had contracted enzyme-linked immunosorbent assay-confirmed A cantonensis infection while working in Taiwan. All three workers had consumed either roasted snails or raw snails flavored with seasoning while drinking wine. This study investigated possible risk factors for A cantonensis, including naturally occurring A cantonensis in A canaliculatus snails, viability of third-stage A cantonensis larvae in raw seasoned snails and in roasted snails, infectivity of larvae, and effects of alcohol while consuming snails. Positive infection rates in snails from five different irrigation canals in south Taiwan ranged from 12.3% to 29.4% and the average number of motile larvae per infected snail ranged from 36 to 65. The number of motile and coiled larvae in snail meat after 120 minutes seasoning was 93 (27.7%) and 233 (69.3%), respectively. After 20 minutes of roasting, most larvae in the snail meat were dead. The infectivities of motile and coiled larvae from snail meat after 60 minutes seasoning were 53.2% and 33.2%, respectively, and those from snail meat after 5 minutes roasting were 33.2% and 7.0%, respectively. Eating Taiwan A canaliculatus snails raw is extremely risky given their high infection rates and infection intensities. Even after 120 minutes seasoning or after 20 minutes roasting, snail meat should be considered unsafe for human consumption. Finally, experimental rodent studies indicated that consuming alcohol while ingesting larvae does not significantly reduced infectivity.

When non-permissive hosts are infected with Angiostrongylus cantonensis, the migration of the worms to the brain and their subsequent development manifests as marked eosinophilic pleocytosis. We used microchambers to demonstrate direct eosinophil chemotactic activity by adding a variety of antibodies into cerebrospinal fluid (CSF) of BALB/c mice 21 days post-infection with A. cantonensis. The antibodies were directed to neutralize eotaxin, RANTES (regulated on activation, normal T-cells expressed and secreted), macrophage inflammatory protein (MIP)-1alpha, and platelet-activating factor (PAF), respectively. Eosinophil migration into the polycarbonate membrane covering CSF with anti-eotaxin or anti-MIP-1alpha antibodies was significantly lower than that for antibody-free CSF (Student's t test: p0.01, p0.05). We also collected CSF from mice 21 days after infection with 10, 20, 30, 40, and 50 third-stage larvae (L3) respectively for dose-dependent testing, and 40 L3 at days 7, 14, and 21 after infection for time-dependent testing. Chemokine production in CSF was affected by A. cantonensis infection intensity and post-infection time. In conclusion, eotaxin and MIP-1alpha released in the CSF of A. cantonensis-infected mice have eosinophil chemotactic activity in this in vitro assay.