[Changes of serum anti-schistosome antibody levels in schistosomiasis japonica patients after treatment].

OBJECTIVE: To investigate the changes of serum anti-schistosome antibody titers in schistosomiasis japonica patients after treatment, in order to provide the evidence for formulating the schistosomiasis surveillance program in marshland and lake regions. METHODS: Upon prospective cohort study, the stool examination positive schistosomiasis patients and blood examination positive suspected patients (the titer was more than 1:80, including 1:80) were selected as the research objects in Jiangling County in 2014, and they received the 2-day praziquantel therapy. Half year, one year and two years after the treatment, their blood samples and fecal samples were collected for IHA anti-schistosome antibody detections and schistosome egg and miracidium detections. RESULTS: In 2014, the stool examination positives were 251, and the majority of them were over 41 years old, accounting for 93.23% (234/251) ; 581 cases of high antibody titers were detected by the IHA method, and the majority of them were over 41 years old, accounting for 89.16% (518/581) . Half year, one year and two years after the treatment, among the stool examination positives, the negative conversion rates of stool positives were 99.60% (250/251), 100% (239/239) and 100% (234/234) respectively and the negative conversion rates of antibody positives were 21.91% (55/251), 64.11% (156/239) and 76.89% (193/234) respectively. In the high antibody titer positives, the negative conversion rates were 38.04% (221/581), 64.11% (359/560), and 77.86% (429/551) respectively, Half year, one year and two years after the treatment. There were statistically significant differences among the antibody negative conversion rates by χ2 test (χ2 = 77.538, 183.412, 25.469 respectively, all P < 0.001) . The geometric mean values of antibody titers of different durations between 2 groups were analyzed by 2-independent-samples T test, and the geometric mean values of antibody titers between the 2 groups were different before the treatment (t = 23.576, P < 0.01), but the geometric mean values of antibody titers between the 2 groups were not different 6 months, 1 year and 2 years after the treatment (t = -0.046, 1.165, -0.132, P = 0.964, 0.245, 0.895 respectively). CONCLUSIONS: The levels of serum anti-schistosome antibody degrade slowly in schistosomiasis japonica patients after the treatment, and the results of IHA tests cannot distinguish the current schistosome infection from previous schistosome infection. Therefore, it is necessary to develop the specific diagnostic technology for schistosome infection in order to meet the need of monitoring.

Survey of knowledge and practice of residents about schistosomiasis preven-tion and control in endemic areas of Jingzhou City / 中国血吸虫病防治杂志

Objective To investigate the knowledge and practice of residents about schistosomiasis prevention and control in endemic areas of Jingzhou City,Hubei Province after the disease transmission being controlled,so as to provide the valuable in-formation for formulating an efficient health education and intervention strategy.Methods The residents were selected by using the cluster sampling method and investigated with questionnaires in Jiangling County and Gong'an County,Jingzhou City,Hu-bei Province,and the data were analyzed by using the descriptive analysis method,Chi-square tests and logistic regression.Re-sults In a total,826 available questionnaires were obtained with 100% of valid rate.Among them,97.0% of the interviewee knew schistosomiasis,and 86.3% knew that the infection happened by contacting water containing cercariae.The residents in el-der age(41-84 years)had higher awareness rates than the residents in lower age(6-17 years),about the regions of epidemic area(χ 2=57.860),infection route of schistosomiasis(χ 2=87.045),advanced schistosomiasis symptoms(χ 2=27.268)and On-comelania hupensis being as intermediate host(χ 2=55.856)(all P<0.05).The males had higher awareness rates of epidemic areas than the females(χ2=13.442,P<0.05).For personal behavior,36.6% of the interviewee had experience of contacting lake or pond water many times a day,and 66.5% had the willingness to participate in schistosomiasis health education.Conclu-sion In the investigation areas,Jiangling County and Gong'an County,the awareness rates of the residents about schistosomia-sis prevention and control are higher,and we should strengthen the health education and behavior intervention,especially in the students of middle and primary schools to help them have the self-protection ability efficiently.

Changes of serum anti-schistosome antibody levels in schistosomiasis japoni-ca patients after treatment / 中国血吸虫病防治杂志

Objective To investigate the changes of serum anti-schistosome antibody titers in schistosomiasis japonica pa-tients after treatment,in order to provide the evidence for formulating the schistosomiasis surveillance program in marshland and lake regions.Methods Upon prospective cohort study,the stool examination positive schistosomiasis patients and blood exami-nation positive suspected patients(the titer was more than 1:80,including 1:80)were selected as the research objects in Jian-gling County in 2014,and they received the 2-day praziquantel therapy.Half year,one year and two years after the treatment, their blood samples and fecal samples were collected for IHA anti-schistosome antibody detections and schistosome egg and mira-cidium detections. Results In 2014,the stool examination positives were 251,and the majority of them were over 41 years old,accounting for 93.23%(234/251);581 cases of high antibody titers were detected by the IHA method,and the majority of them were over 41 years old,accounting for 89.16%(518/581).Half year,one year and two years after the treatment,among the stool examination positives,the negative conversion rates of stool positives were 99.60%(250/251),100%(239/239)and 100%(234/234)respectively and the negative conversion rates of antibody positives were 21.91%(55/251),64.11%(156/239)and 76.89%(193/234)respectively.In the high antibody titer positives,the negative conversion rates were 38.04%(221/581),64.11%(359/560),and 77.86%(429/551)respectively,Half year,one year and two years after the treatment.There were statistically significant differences among the antibody negative conversion rates by χ2test(χ2=77.538,183.412,25.469 respectively,all P<0.001).The geometric mean values of antibody titers of different durations between 2 groups were analyzed by 2-independent-samples T test,and the geometric mean values of antibody titers between the 2 groups were different before the treatment(t=23.576,P<0.01),but the geometric mean values of antibody titers between the 2 groups were not different 6 months,1 year and 2 years after the treatment(t=-0.046,1.165, -0.132,P=0.964, 0.245,0.895 respectively). Conclu-sions The levels of serum anti-schistosome antibody degrade slowly in schistosomiasis japonica patients after the treatment, and the results of IHA tests cannot distinguish the current schistosome infection from previous schistosome infection.Therefore, it is necessary to develop the specific diagnostic technology for schistosome infection in order to meet the need of monitoring.

[Survey of knowledge and practice of residents about schistosomiasis prevention and control in endemic areas of Jingzhou City].

OBJECTIVE: To investigate the knowledge and practice of residents about schistosomiasis prevention and control in endemic areas of Jingzhou City, Hubei Province after the disease transmission being controlled, so as to provide the valuable information for formulating an efficient health education and intervention strategy. METHODS: The residents were selected by using the cluster sampling method and investigated with questionnaires in Jiangling County and Gong'an County, Jingzhou City, Hubei Province, and the data were analyzed by using the descriptive analysis method, Chi-square tests and logistic regression. RESULTS: In a total, 826 available questionnaires were obtained with 100% of valid rate. Among them, 97.0% of the interviewee knew schistosomiasis, and 86.3% knew that the infection happened by contacting water containing cercariae. The residents in elder age (41-84 years) had higher awareness rates than the residents in lower age (6-17 years), about the regions of epidemic area (χ2 = 57.860), infection route of schistosomiasis (χ2 = 87.045), advanced schistosomiasis symptoms (χ2 = 27.268) and Oncomelania hupensis being as intermediate host (χ2 = 55.856) (all P < 0.05) . The males had higher awareness rates of epidemic areas than the females (χ2 = 13.442, P < 0.05) . For personal behavior, 36.6% of the interviewee had experience of contacting lake or pond water many times a day, and 66.5% had the willingness to participate in schistosomiasis health education. CONCLUSIONS: In the investigation areas, Jiangling County and Gong'an County, the awareness rates of the residents about schistosomiasis prevention and control are higher, and we should strengthen the health education and behavior intervention, especially in the students of middle and primary schools to help them have the self-protection ability efficiently.

[Distribution features of wild feces in schistosomiasis endemic areas in Jiangling County, Hubei Province].

OBJECTIVE: To understand the spatial distribution characteristics of wild feces in schistosomiasis endemic areas of Jiangling County, Hubei Province and further explore the source of infection efficiently, so as to provide the evidence for the development of corresponding monitoring and response technology. METHODS: In 2011, the fresh wild feces were investigated every two months in the selected 15 villages by the severity of historical endemic in Jiangling County. The schistosome miracidium hatching method was used to test the schistosome infection of the wild feces. The descriptive analysis and spatial analysis were used for the description of the spatial distribution of the wild feces. RESULTS: Totally 701 wild feces samples were collected with the average density of 0.055 6/100 m2, and the positive rate of the wild feces was 11.70% (82/701). The results of the regression analysis showed a positive spatial correlation between the positive rate of wild feces and the rate of human infection, the area with infected Oncomelania hupensis and the number of fenced cattle, and the corrected R2 of the model was 0.58. CONCLUSIONS: The infection rate of wild feces is positively correlated with the rate of human infection, area with infected O. hupensis and number of fenced cattle in space in Jiangling County, so the prevention and control measures could be conducted according to the spatial distribution of the positive wild feces.

[Pattern analysis of tempo-spatial distribution of schistosomiasis in marshland epidemic areas in stage of transmission control].

OBJECTIVE: To investigate the tempo-spatial patterns of schistosomiasis in Jiangling County, Hubei Province, so as to identify the risk areas and provide the scientific evidence in following intervention plans for marshland epidemic areas in the stage of transmission control. METHODS: The schistosomiasis epidemiological data in Jiangling County from 2009 to 2013 together with the related geographical information were collected and analyzed. The tempo-spatial distribution patterns were analyzed by the spatial autocorrelation analysis and spatial clustering analysis. RESULTS: The human infection rate was decreased from 2.15% in 2009 to 0.63% in 2013, which was the historically low level. The results of tempo-spatial analysis showed that there were spatial clustering effects in human schistosomiasis infection for each of the years. The values of spatial autocorrelation index Moran's I were statistically significant. Eighteen and thirty-five clusters were detected by using SatScan and FlexScan software, respectively. CONCLUSIONS: From 2009 to 2013, the schistosomiasis endemic situation in Jiangling County presented a decline trend and reached the historical low level. The identified spatial clustering areas should be targeted as the prioritized areas for schistosomiasis control.

[Oncomelania hupensis snail control effects of molluscicides with different formulations in field in marshland and lake regions].

OBJECTIVE: To observe the Oncomelania hupensis snail control effects of molluscicides with different formulations in the ditch with unstable water level in field of marshland and lake areas, so as to provide the evidence for formulating the prevention strategies. METHODS: A drainage channel with O. hupensis snails in Jiangling County, Jingzhou City were selected as the study field, then it was divided into 6 segments, except 1 segment was treated as the blank control group for observing the natural mortality rate of the snails, the other 5 segments were treated as observation groups, where 4% niclosamide ethanolamine salt powder, 5% niclosamide ethanolamine salt granule, 25% suspension concentrate of niclosamide ethanolamine salt, 26% suspension concentrate of metaldehyde and niclosamide ethanolamine salt, 50% niclosamide ethanolamine salt wettable powder were applied respectively. Before and after the mollusciciding, the snail surveys were carried out through the systematic sampling method, and the short- and long-term effects of snail control were observed, and the mortality rates of the snails on the slope above the water level and those below the water level were compared. RESULTS: When 7 d and 15 d after mullusciciding, the mortality rates of snails on the slope above the water level in each observation group were 79.52%-97.87% and 90.43%-96.30%, respectively, when compared with those before mollusciciding, all the differences were statistically significant (all P < 0.01). When 7 d after mullusciciding, the mortality rates of snails below the water level in each observation group were 17.11%-50.00%, which were all lower than those of the snails on the slope above the water level in the corresponding groups (all P ＜ 0.05); when 15 d after mullusciciding, the rates were 9.43%-95.24%, and those in 25% suspension concentrate of niclosamide ethanolamine salt, 26% suspension concentrate of metaldehyde and niclosamide ethanolamine salt, 50% niclosamide ethanolamine salt wettable powder groups were all lower than those of the snails on the slope above the water level in the corresponding groups (all P ＜ 0.01). Compared with the densities of living snails before mollusciciding, those 6 months after mollusciciding in each observation group decreased by 70.21%-78.98%. CONCLUSIONS: The molluscicides in the formulation of powders and granule are suitable for both the snail environment with or without water, while those in the formulation of suspension agents and wettable powders are suitable only for environments with water.

[Effect of two-level community-based health education pattern on schistosomiasis control].

OBJECTIVE: To implement a two-level community-based health education pattern of schistosomiasis in residents of endemic areas in marshland and lake regions, so as to explore the suitable pattern of health education under hypo-endemic situation. METHODS: Two schistosomiasis endemic villages in Jiangling County, Hubei Province were collected as study areas, and among which, one village was treated as an intervention group, where the two-level community-based health education pattern as well as regular control measures was implemented; the other village was a control group, where only regular control measures were implemented. The awareness rates on schistosomiasis control, the rates of correct behavior and the compliance rates of examination, treatment and chemotherapy of the two groups before and after the intervention were compared. RESULTS: According to the results of the baseline survey in 2014, the awareness rates of schistosomiasis control of the intervention and control groups were 84.00% and 77.45%, respectively, the correct rates of behavior of the two groups were 72.00% and 63.73%, respectively, and the compliance rates of the treatment were 80.36% and 82.28%, respectively, there were no statistically significant differences between all the above rates of the two groups (all P > 0.05). After the intervention of the two-level community-based health education, the correct rates of behavior, and the compliance rates of examination and chemotherapy of the two groups were 92.31% and 80.37%, 95.11% and 82.55%, 84.13% and 63.64%, respectively, and the differences between all the rates above of the two groups were statistically significant (all P < 0.05). When compared to those before intervention, the growing rates of the compliance rates of examination, treatment and chemotherapy of the intervention group were 20.97%, 15.33% and 23.29%, respectively, while those of control group were 14.27%, 4.17%, -3.77%, respectively, the growing rates of the intervention groups were higher than those of the control groups. CONCLUSIONS: Through the two-level community-based pattern of health education, the compliance rates of examination and treatment of the residents have improved, and therefore, the pattern is suitable for popularization and application in marshland and lake regions.