Infection rate of Schistosoma japonicum in the snail Oncomelania hupensis quadrasi in endemic villages in the Philippines: Need for snail surveillance technique.

Schistosomiasis japonica is one of seven NTDs endemic in the Philippines that continues to threaten public health in the country. The causative agent, the blood fluke Schistosoma japonicum, uses an amphibious snail Oncomelania hupensis quadrasi which can harbor larval stages that multiply asexually, eventually producing the infective cercariae which are shed into the water. Contamination of freshwater bodies inhabited by the snail intermediate host occurs through release of human and animal feces containing S. japonicum eggs. Miracidia hatching from these eggs subsequently infect the snails that inhabit these water bodies. The degree of fecal contamination can vary across snail sites and influences snail infection rates in these sites. In this study, conventional malacological surveys using intensive manual search for snails were conducted from 2015 to 2016 in seven selected endemic provinces, namely Leyte and Bohol in the Visayas and Surigao del Norte, Agusan del Sur, Bukidnon, Lanao del Norte and Compostela Valley in Mindanao. A total of 6,279 O. hupensis quadrasi snails were collected from 38 snail sites. The municipality of Trento in Agusan del Sur recorded the highest number of snail sites (7) that yielded O. hupensis quadrasi snails while only one snail site was found positive for O. hupensis quadrasi snails in Kapatagan in Lanao del Norte and Talibon in Bohol. Alegria in Surigao del Norte yielded the highest number of snail sites (5) that were found to harbor snails positive for S. japonicum infection. The snail infection rates in this municipality ranged from 0.43% to 14.71%. None of the snails collected from Talibon in Bohol was infected. Bohol is the only province among the 28 schistosomiasis-endemic provinces which has reached near elimination status. Snail infection rates were found to vary considerably across snail sites, which could be due to the degree of fecal contamination of the snail sites and their connectivity to water that can serve as contamination source.

Infection rate of Schistosoma japonicum in the snail Oncomelania hupensis quadrasi in endemic villages in the Philippines: Need for snail surveillance technique

@#Schistosomiasis japonica is one of seven NTDs endemic in the Philippines that continues to threaten public health in the country. The causative agent, the blood fluke Schistosoma japonicum, uses an amphibious snail Oncomelania hupensis quadrasi which can harbor larval stages that multiply asexually, eventually producing the infective cercariae which are shed into the water. Contamination of freshwater bodies inhabited by the snail intermediate host occurs through release of human and animal feces containing S. japonicum eggs. Miracidia hatching from these eggs subsequently infect the snails that inhabit these water bodies. The degree of fecal contamination can vary across snail sites and influences snail infection rates in these sites. In this study, conventional malacological surveys using intensive manual search for snails were conducted from 2015 to 2016 in seven selected endemic provinces, namely Leyte and Bohol in the Visayas and Surigao del Norte, Agusan del Sur, Bukidnon, Lanao del Norte and Compostela Valley in Mindanao. A total of 6,279 O. hupensis quadrasi snails were collected from 38 snail sites. The municipality of Trento in Agusan del Sur recorded the highest number of snail sites (7) that yielded O. hupensis quadrasi snails while only one snail site was found positive for O. hupensis quadrasi snails in Kapatagan in Lanao del Norte and Talibon in Bohol. Alegria in Surigao del Norte yielded the highest number of snail sites (5) that were found to harbor snails positive for S. japonicum infection. The snail infection rates in this municipality ranged from 0.43% to 14.71%. None of the snails collected from Talibon in Bohol was infected. Bohol is the only province among the 28 schistosomiasis-endemic provinces which has reached near elimination status. Snail infection rates were found to vary considerably across snail sites, which could be due to the degree of fecal contamination of the snail sites and their connectivity to water that can serve as contamination source.

Discovery of Liopiophila varipes and Protopiophila contecta (Diptera: Piophilidae) from human cadavers.

Here, we present two cases in which larvae of the family Piophilidae were detected in human cadavers. Both cases were found in Tochigi Prefecture, which is located in the middle of Honshu Island, Japan. Case 1: A corpse was found hanging in the sun lounge of a house. Dipteran larvae were collected from inside the spinal canal, despite no visible breach on the skin. The adults derived from these larvae were identified as Piophila casei (Linnaeus, 1758) and Liopiophila varipes (Meigen, 1830). Case 2: Skeletal human remains were found in a mountainous forest. Dipteran larvae were detected in the bone marrow cavity of a tibial section during autopsy. One adult fly derived from the larvae was identified as Protopiophila contecta (Walker, 1860). This is the first report of the identification of L. varipes and P. contecta in human cadavers.

Characteristics of granuloma formation and liver fibrosis in murine schistosomiasis mekongi: a morphological comparison between Schistosoma mekongi and S. japonicum infection.

A histopathological study was performed to clarify the characteristics of granuloma formation and liver fibrosis in Schistosoma mekongi infection in comparison with S. japonicum infection. Mice were exposed to S. mekongi (Laotian strain) and S. japonicum (Japanese strain) cercariae, and were dissected at 6, 8, 12, 16, and 20 weeks post-exposure. In the liver, granulomas in S. mekongi infection were cellular, initially organized with foam cells, and continuously appeared in the intralobular area, while granulomas in S. japonicum infection were fibrous and did not continuously appear in the intralobular area. Portal fibrosis was not seen in S. mekongi infection, but was commonly seen in S. japonicum infection in the later weeks. Granulomas in the small intestine were seen mainly in the submucosa with foam cells in S. mekongi infection and without foam cells in S. japonicum infection. The lung granulomas contained mainly histiocytes in both S. mekongi and S. japonicum infection. The absence of portal fibrosis in S. mekongi infection allows schistosome eggs to infiltrate into the intralobular area continuously, which can be what lies behind the ultrasonographic differences; the echogenic network pattern as was seen in S. japonicum infection, has not been noted in S. mekongi infection.