Dang H.,National Institute of Parasitic Diseases |
Xu J.,National Institute of Parasitic Diseases |
Li S.-Z.,National Institute of Parasitic Diseases |
Cao Z.-G.,Anhui Institute of Schistosomiasis Control |
And 4 more authors.
International Journal of Environmental Research and Public Health | Year: 2014
Schistosomiasis japonica, caused by Schistosoma japonicum infection, remains a major public health concern in China, and the geographical distribution of this neglected tropical disease is limited to regions where Oncomelania hupensis, the intermediate host of the causative parasite, is detected. The purpose of this study was to monitor the transmission of S. japonicum in potential risk regions of China during the period from 2008 through 2012. To monitor the transmission, 10 fixed surveillance sites and 30 mobile sentinel sites were selected in 10 counties of four provinces, namely Anhui, Jiangsu, Chongqing and Hubei. There were 8, 9, 6, 2 and 3 cases infected with S. japonicum detected in the 30 mobile sentinel sites during the 5-year study period, while 27 subjects were positive for the antibody-based serum test in the 10 fixed sentinel sites; however, no infection was found. In addition, neither local nor imported livestock were found to be infected. No O. hupensis snails were detected in either the fixed surveillance or the mobile sentinel sites; however, the snail host was found to survive and reproduce at Chaohu Lake, inferring the potential of transmission of the disease. It is suggested that the continuous surveillance of schistosomiasis japonica should be carried out in both the endemic foci and potential risk regions of China, and an active, sensitive system to respond the potential risk of transmission seems justified. © 2014 by the authors; licensee MDPI, Basel, Switzerland. Source
Wang S.-X.,Wuhan University |
Wang S.-X.,Hubei Institute of Schistosomiasis Control |
Shi J.-M.,Wuhan University |
Shi J.-M.,Hubei Institute of Schistosomiasis Control |
And 6 more authors.
Chinese Journal of Schistosomiasis Control | Year: 2012
Objective: To evaluate the preventive effect of Fangyouling (a plant cercaricide) for schistosome infection in the field. Methods: Villagers contacting schistosome infested water in 3 administrative villages in Hubei Province were randomly selected, and the villagers rubbing Fangyouling before they contacted with the infested water were divided into Group I (159 cases) and those not rubbing Fangyouling before they contacted with the infested water were divided into Group II (172 persons). All the villagers were investigated by questionnaire, and their infections of schistosome were tested by sera and fecal examinations. Results: There were no differences of constituent ratios of gender, age, occupation, time and type of infested water contact between the two groups (all P values > 0.05). The positive rates of sera and fecal examinations were 3.14%; and 1.87%, respectively in Group I, and the positive rates of sera and fecal examinations were 9.30% and 6.40%, respectively in Group II, and there were significant differences between both the results of sera and fecal examinations of Group I and Group II (both P values < 0.05). In Group I, there were 110 people who completely embrocated Fangyouling, and their positive rates of sera and fecal examinations were 0.91% and 0, respectively. There are 42 people who incompletely embrocated Fangyouling, and their positive rates of sera and fecal examinations were 8.16% and 6.12%, respectively, and there were significant differences (both P values < 0.05). Conclusions: The preventive effect of schistosome infection of Fangyouling is significant. Incomplete embrocating may be one of the possible reasons for people still being infected with schistosome after rubbing the protective agent. Source
Yuan Y.,Hubei University |
Yuan Y.,Hubei Institute of Schistosomiasis Control |
Dong H.,Hubei University |
Xu X.,Hubei Institute of Schistosomiasis Control |
And 10 more authors.
Malacologia | Year: 2011
A novel molluscicide, derived from niclosamide, the salt of quinoid-2′,5-dichloro-4′-nitrosalicylanilide (LDS) was recently developed in China. The molluscicidal activity of LDS was compared with the commonly used molluscicide niclosamide (WPN) by immersion at seven concentrations; 0.05, 0.1, 0.2, 0.4, 0.8, 1.6, and 3.2 mg/L, and with spraying and powdering methods (dosages of 0.2, 0.4, and 0.8 g/m2) in the laboratory and the field. We recorded mortality at 1 d, 3 d, and 7 d. The results showed that at 0.4 mg/L immersion exposure for 72 hours, snail mortalities for LDS and WPN were 100% and 96.70% respectively in the lab, and 100% and 95.33 ± 1.15% respectively in the field. With a dosage of 0.8 g/m2 exposure for 7 d by spraying, snail mortalities for LDS and WPN were 100% and 97.33 ± 2.30% respectively in the lab, and 99.27 ± 1.27% and 97.47 ± 3.11 % in the field. With a dosage of 0.8 g/m 2 exposure at 7 d by powdering, snail mortalities for LDS and WPN were both 98% in the lab, and 100% in the field. These results from three different methods show that molluscicidal effects were similar in the lab and the field. However, LDS is much cheaper than WPN, and LDS is less toxic to fish than WPN. Therefore, LDS might be more useful than WPN for controlling snails in endemic areas of schistosomiasis in China. Source