Cross-sectional Investigation On Soil-transmitted Helminth Infections In One Village Of West China And Efficacy Evaluation Of Chemotherapy Schemes On Hookworm

ObjectiveThe purpose of the research was to study on current situation of soil-transmitted helminth infection and its factors on transmission by cross-sectional survey. Then, efficacy evaluation of different kind of chemotherapy schemes on hookworm infection was investigated by field trial.MethodsThis study has two parts. One is to Study on current situation of soil-transmitted helminth infection of the field; the other is to make efficacy evaluation of different chemotherapy schemes on hookworm and their applicability.Firstly, pilot study was performed by using cross-cetional survey. The residents over 2 years old were selected as eligible study targets for the survey. All eligible residents' stool were collected and examined by Kato-Katz technique. Simultaneously, hemoglobinometry were tested for all eligible residents. All eligible residents were invited to answer a questionnaire including personal information and their hygienic habits, family health status and economy income. After finished the survey, 3 aspects of analysis were undertaken: 1) the demographic characteristics of soil-transmitted helminth infection were analyzed based on results of Kato-Katz examination. 2) The influence factors on soil-transmitted helminth infection were analyzed by chi-square test and logistic regression. 3) An asset index for each family was stratified based on living conditions and household assets to compare the socio-economic factors and the soil-transmitted helminth infection level.Secondly, based on the etiological examination information in Part 1, patients infected with hookworm were selected as eligible residents. All of eligible residents were classified into 3 groups in random and treated by single dose of albendazole, single dose of tribendimidine and combined therapy with albendazol and Pyrantel. The adverse event informations after patients took the drug were collected and analyzed. Evaluate drug efficacy by "2 samples 6 smears" stool test. The statistic analysis was performed as follows: 1) Compare the recovery rate and worm egg reduction rate for three chemotherapy schemess by chi square test and T test. 2) Incidence rate of adverse event for each trial were compared for three chemotherapy schemess.ResultsThrough the study on current situation of soil-transmitted helminth infection of the field, we have results as follows: A total of 473 people eligible residents of Dachi Village, Changning County , Sichuan Province attended this study. The soil-transmitted helminth infection rate of total eligible residents was 64.5%. The infection rates of hookworm, trichuris and ascaris were 48.4%, 8.5% and 31.5%. The soil-transmitted helminth infection rate among men and women were 61.8% and 67.2%. The eligible residents between 15-30 years old had a higher infection rate. The eligible residents who had the education level of graduated from elementary school also had a higher infection rate. The weather and geographical environment were suitable for the transmission of soil-transmitted helminth. Based on the result of chi square test, the influence factor on soil-transmitted helminth infection were the exposure time in the field, frequency of washing hands, the type of water source, the type of latrine and the family income. Also, soil-transmitted helminth infection was significantly associated with anemia and dermatitis cause by hookworm larve. Based on the result of logistic regression, soil-transmitted helminth infection was significantly associated with 4 factors; they are frequency of washing hands, the type of water source, the type of latrine and the family income.1) The recovery rate single dose of albendazole, single dose of tribendimidine and combined therapy with albendazole and pyrantel on hookworm are 65.0%, 64.5% and 84.1%. Based on the result of chi square test, albendazole and tribendimidine have no significant difference in the efficacy on hookworm. 2) The adverse event rate of single dose of albendazole, single dose of tribendimidine and combined therapy with albendazole and pyrantel on hookworm are 13.3%, 25.0% and 11.1%. Based on the result of chi square test, only group tribendimidine and combined therapy with albendazole and pyrantel have significant difference.ConclusionThis study indicates that the influence factors of soil-transmitted helminth infections in the nightsoild-fertilizer area in west China are highly related to daily activities, such as frequency of washing hands, the type of water source, and the type of latrine and the family income. The effect of tribendimidine and albendazole are similar. These results provide useful information to formulate the prevention strategy of soil-transmitted helminth in west China and help government to make the decision on selecting chemotherapy schemes.