Prevalence and risks of soil transmitted helminths among Ethiopian school children:A cross-sectional study

Objective:To assess the prevalence and associated factors of soil transmitted helminths(STHs)among Endemata primary school in North West Ethiopia,2021.Methods:A cross-sectional study with 195 school children was conducted from May to July 2021 at Endemata primary school.The study participants were selected by using systematic random sampling technique.Stool samples were processed via direct wet mount and formol-ether concentration techniques.Data was entered by Epi-Dara version 3.1 and data analysis was done using SPSS version 20.0.Variables were considered to be statistically significant if P<0.05 at 95%confidence level.Results:The overall prevalence of STHs was 10.8%(95%CI 7.1-16.0).The prevalence of Ascaris lumbricoides,hookworm and Trichuris trichiura were 5.6%(95%CI 3.1-9.9),3.1%(95%CI 1.3-6.7)and 2.1%(95%CI 0.6-5.3),respectively.Grade 1-4 students were more likely to get infected with STHs as compared to grade 5-8 students(adjusted OR 4.7,95%CI 1.3-16.6).Students who did not have latrines at their home were at higher risk to develop STHs infection comparing with those who had latrine at their home(adjusted OR 5.0,95%CI 1.7-15.2).Similarly,the school children who did not wear shoes were more likely to be infected by STH parasite than those who did it(adjusted OR 6.3,95%CI 1.9-20.7).The odds of being infected by STH parasites in children who did not trim their fingernails were 4.9 as compared to those who did it(adjusted OR 4.9,95%CI 1.5-15.7).Conclusions:The prevalence of STHs among Endemata primary school children was low.Student grade level,latrine availability,shoes wear and nail status were significantly associated with STHs infection.Therefore,we recommend policy makers and stakeholders to follow the integration of deworming with water,hygiene and sanitation as well as the consistent health education of school children to control and prevent STH infections.

High prevalence of soil-transmitted helminths in Southern Belize-highlighting opportunity for control interventions

Objective:To assess prevalence and intensity of soil-transmitted helminths(STH) in school age children of two southern districts as baseline information prior to implement a deworming program against intestinal parasites as part of an integrated country development plan.Methods:Children randomly selected from urban and rural schools in Southern Belize provided one stool sample each,analysed by the Kato-Katz method to assess prevalence and intensity of STH infections.Epi Info software was used for data analysis;Chi-square test and Fischer exact test were applied to compare group proportions;P<0.05 was considered of statistical significance;descriptive statistics were expressed as percentages.Results:A total of 500 children from 10 schools participated in the study from May to December2005.Prevalence of STH ranged between 40%and 82%among schools,with a median of 59.2%;the majority of light intensity,and with 2.2%high intensity infection.Trichuris and Axaris infections presented similar frequency in children aged from 6 to 9 years old;hookworm infections tended to be more frequent in the older group 10 to 12 years old.Statistical significances(P≤0.01)were found in children in rural schools infected with any species of STH,in moderate Trichuris infections,in hookworm infections in rural areas with strong Mayan presence and in Ascaris infections in children of Mayan origin.Conclusions:High prevalence of STH in Southern Belize provided sound ground for implementing an integrated deworming control program.

Water Resource, Hygienic Practice, and Soil Transmitted Helminthiasis in Some Rural Communities of Osun State, Nigeria

Provision of water, sanitation and hygiene (WASH) resources has been advocated as necessary add-on strategy for sustainable control of soil-transmitted helminthiasis (STH) alongside annual mass drug administration (MDA) of albendazole to endemic communities. This study investigated the burden of STH and status of WASH resources in eight rural communities in Aiyedaade LGA, Osun State, Nigeria. Four of the communities were supported with improved water and hygiene resources (Category A), and another four supported only with improved water resources (Category B). Two hundred and sixteen (216) fresh stool samples were collected from consenting community members and screened for Ascaris lumbricoides, Hookworm and Trichuris trichiura infections using ether concentration method. The status and condition of WASH resources were determined using questionnaire and physical observation. An overall prevalence of 35.2% was observed for any STH infection. Species’ prevalence of Ascaris lumbricoides, Hookworm and Trichuris trichiura prevalence was 33.8%, 22.7%, and 0.5% respectively. Intensity of STH infection was significantly higher in Category A communities than in Category B communities. The prevalence of STH in Category A communities was higher (42.0%) than that in Category B communities (30.1%). There were significant differences (p = 0.000) in STH infections between the two categories. The status of improved water supply was not significantly different (p = 0.3153) in the two categories. Knowledge, attitude, and practices about STH, its transmission and control were low in both categories of communities. These results imply that current implementation of WASH which tends to focus on resource distribution, equity, and coverage, is unlikely to impact on STH transmission and control. Therefore, it is necessary for WASH providers to consider STH transmission control in their planning and implementation of WASH intervention for STH endemic communities.

Spatial Distribution and Modeling of Soil Transmitted Helminthes Infection in Nigeria

Background and Objective: Soil transmitted helminthes (STH) infection affects more than two billion people worldwide with Nigeria having the highest burden in Sub-Saharan Africa. This study examined the spatial and potential distribution of STHs in Nigeria. Materials and Methods: Secondary data were assessed from 98 journals and the prevalence of Ascaris lumbricoides, Trichuris trichiura and hookworms were extracted from them. The spatial distribution of the parasites was performed using DIVA-GIS software. The climatic variables (temperature and precipitation) and elevation variable (altitude) were used in the modeling of the parasites using Maximum Entropy (MaxEnt) modeling tool. Results: The average prevalence of A. lumbricoides, Hookworms and T. trichiura in Nigeria is 25.17%, 16.86% and 9.74% respectively. Delta State (62.08%) had the highest infection of A. lumbricoides followed by Oyo (55.50%) and Kano (44.40%) while 14 states had prevalence of below 20.0%. Akwa Ibom and Kano States had the highest average prevalence of 55.80% for hookworm infections. Delta, Oyo and Benue States had prevalence of 38.08%, 35.80%, and 35.40% respectively while 22 states had prevalence of hookworm below 20.0%. T. trichiura had the least average prevalence among the three STHs. Akwa Ibom State had the highest prevalence for this parasite with 40.40% followed by Lagos, Delta and Kwara States with prevalence values of 24.85%, 24.05% and 23.37% respectively. Other states in the Federation had prevalence values of less than 12% with Federal Capital Territory (FCT), Abuja and Borno States having the least prevalence of 0.80 and 0.90% respectively. The potential distribution that reveals than southern Nigeria has been at high risk of infections. Precipitations of the wettest month, altitude, precipitation of the warmest quarter are the major environmental variables that affect the distribution of STH. Conclusion: Nigeria is characterized by varying prevalence of STHs. All states in Nigeria are endemic for STHs. Southern Nigeria was observed to have higher prevalence of STHs due to the high level of precipitation and low altitude of these regions. “The higher the altitude, the lower the prevalence of STH infections. The higher the temperature and precipitation, the higher the prevalence of STH infections.

Prevalence of Soil-Transmitted Helminths and Intestinal Protozoa among School Children in Lome, Togo

Background: Significant morbidity in children is associated with infectious diseases especially soil-transmitted helminth (STH) infections which are prevalent in sub-Saharan African countries. The objective of this study is to estimate the prevalence of STH and intestinal protozoa among schoolchildren in Lomé, Togo. Patients and Methods: In November 2013, in each of the five districts of the Lomé-commune region, thirty pupils per level of the third, fourth, fifth and sixth grades of five primary schools were included. Each child submitted a single stool sample that was analyzed by the Kato-Katz method for STH. In addition, stool samples of school children selected in third and sixth grades were examined by direct visualization using saline and Lugol’s stain for intestinal protozoa. Results: A total of 2944 children were enrolled at 25 schools. The overall prevalence of STH at schools was 5.0% (range 1.5% to 8.6%), was higher in boys than girls, and increased with age and grade. Hookworm was the most prevalent species (3.4% of children surveyed). Intestinal protozoa were found in 52.2% (765/1465) of children tested and commensal amoebae represented 22.7% of these protozoa identified. Entamoeba histolytica/dispar/moshkovskii and Giardia intestinalis were identified in 2.3% and 11.5% of children, respectively. Co-infestation was noted in 1.35% of children with intestinal helminths and 12.2% of children with protozoa. Conclusion: Although a high prevalence of intestinal protozoa was found in our study, the majority were non-pathogenic protozoa and the low prevalence of STH among school-age children in Lomé-commune region confirms that mass drug administration (MDA) is not needed. Children should receive additional education on best hygiene practices.

<i>Schistosoma mansoni</i>and Soil Transmitted Helminth (STH) Infections among Pregnant Women Attending Primary Health Care Facilities in Lagos Mainland, Nigeria

In a cross-sectional survey among consented pregnant women, rapid diagnostic test (RDT) for malaria was carried out and stool examination was done to detect the presence of Schistosoma mansoni and soil transmitted helminthes using Kato-Katz technique. Intensity of infection was expressed as the number of eggs per gram (epg) of faeces. Prevalence of soil transmitted helminthes was 8.3% and 0.83% for Schistosoma mansoni while none was positive for malaria infection. Lack of co-infection with malaria could be connected with the intermittent preventive treatment with sulphadoxine pyrimethamine (IPTp-SP). Public health impact of soil transmitted helminthes and schistosomiasis infections in pregnancy may necessitate initiation of preventive treatment of helminth infections during pregnancy.

Current Status of Soil-transmitted Nematode Infection in China

Objective To carry out national surveys for ascertaining the current status and trends of soil-transmitted nematode infections in China, providing scientific basis for further developing control strategies. Methods In 1988-1992 （hereinafter abbreriated as ＂survey in 1990＂）, a stratified cluster random sampling method was used in the survey. In 2001-2004 （hereinafter abbreriated as ＂survey in 2003＂）, in order to compare with the survey in 1990, two-characteristic stratified cluster random sampling method was used and 687 investigation spots were sampled from the 2848 spots selected in the survey in 1990. Kato-Katz thick smear method was used to examine the eggs of soil-transmitted nematodes in fecal samples. Results The prevalence rates were 53.6% and 19.6% for soil-transmitted nematodes, 14.6% and 6.120% for hookworms, 44.6% and 12.7% for Ascaris lumbricoides, 17.4% and 4.630% for Trichuris trichiura in survey 1990 and survey 2003, respectively. The prevalence rates of soil-transmitted nematodes were higher in 13 provinces than the average level in China in the survey in 1990, and higher in 8 provinces than the average level in the survey in 2003. The prevalence of hookworms, Ascaris lumbricoides, Trichuris trichiura and the overall prevalence of soil-transmitted nematodes were higher in females than in males. It is estimated from the results of survey in 2003 that the number of persons with soil-transmitted nematode infections in the country is about 129 million, less than that in the survey in 1990. Conclusion The prevalence of soil-transmitted nematodes has declined considerably but is still relatively high in some provinces and autonomous regions. Control activities and socioeconomic development may have contributed to the decreased prevalence.

Time-Domain Analysis of Underground Station-Layered Soil Interaction Based on High-Order Doubly Asymptotic Transmitting Boundary

Based on the modified scale boundary finite element method and continued fraction solution,a high-order doubly asymptotic transmitting boundary(DATB)is derived and extended to the simulation of vector wave propagation in complex layered soils.The high-order DATB converges rapidly to the exact solution throughout the entire frequency range and its formulation is local in the time domain,possessing high accuracy and good efficiency.Combining with finite element method,a coupled model is constructed for time-domain analysis of underground station-layered soil interaction.The coupled model is divided into the near and far field by the truncated boundary,of which the near field is modelled by FEM while the far field is modelled by the high-order DATB.The coupled model is implemented in an open source finite element software,OpenSees,in which the DATB is employed as a super element.Numerical examples demonstrate that results of the coupled model are stable,accurate and efficient compared with those of the extended mesh model and the viscous-spring boundary model.Besides,it has also shown the fitness for long-time seismic response analysis of underground station-layered soil interaction.Therefore,it is believed that the coupled model could provide a new approach for seismic analysis of underground station-layered soil interaction and could be further developed for engineering.

Risk Factors for Geo-Helminthiasis in Children Aged 6 - 36 Months in a Rural Health District in Cameroon

Introduction and Objectives: Soil-Transmitted-Helminthiasis (STH) is a public health problem in Cameroon. The control strategies currently in place, particularly chemoprevention, has shortcomings linked to the target population, which are school-age children. The objective was to determine the prevalence and the risk factors associated with geo-helminthiasis in children aged 0 to 3 years in a rural health district. Method: From December 2020 to May 2021, a descriptive and analytical cross-sectional study of 376 children between 6 and 36 months was carried out in the Akonolinga health district. This was a cluster sampling in 4 health areas. Stool samples were collected and analysed using the mini-FLOTAC method. The results expressed as the number of eggs per gram of stool. A questionnaire on socio-demographic and lifestyle data was administered to the parents. The Chi-squared test was used to measure the association between geo-helminth infection and the data collected. A multivariate analysis using logistic regression was performed (p 0.05). Results: The prevalence of STH was 19.4% (Ascaris lumbricoides: 16% and Trichuris trichiura: 8%). Risk factors were: consumption of contaminated water (AOR = 1.93 [1.03 - 3.6];p = 0.040), early contact of the child with the ground (before age of 4 months) (AOR = 4.9 [2.1 - 11.37];p .001), habit of walking barefoot (AOR = 2.91 [1.1 - 7.97];p = 0.038), and living in a habitat with unpaved ground (AOR = 7.4 [1.55 - 35.7];p = 0.012). Conclusion: The prevalence of STHs in infants was high. Preventive chemotherapy should be extended to this age-group, and other measures intensified.

Soil-transmitted helminth infection in school age children in Sierra Leone after a decade of preventive chemotherapy interventions

Background:Baseline mapping of soil-transmitted helminth(STH)infections among school age children(SAC)in 2008-2009 found high or moderate prevalence in 13 of the 14 districts in Sierra Leone.Following these surveys,mass drug administration(MDA)of mebendazole/albendazole was conducted biannually at national level targeting pre-school children(PSC)aged 12-59 months and intermittently at sub-national level targeting SAC.In addition,MDA with ivermectin and albendazole for eliminating lymphatic filariasis(LF)has been conducted nationwide since 2010 targeting individuals over 5 years of age.Each MDA achieved high coverage,except in 2014 when all but one round of MDA for PSC was cancelled due to the Ebola emergency.The objective of the current study was to determine the prevalence and intensity of STH infections among SAC after a decade of these deworming campaigns.Methods:Seventy-three schools in 14 districts were purposefully selected,including 39 schools from the baseline surveys,with approximately two sites from each of low,moderate and high prevalence categories at baseline per district.Fresh stool samples were collected from 3632 children aged 9-14 years(male 51%,female 49%)and examined using the Kato Katz technique.Results:The prevalence of STH infections in Sierra Leone decreased in 2016 compared to 2008:Ascaris lumbricoides 4.4%(95%confidence interval[CI]:3.7-5.1%)versus 6.6%(95%CI:0-25%),Trichuris trichiura 0.7%(95%CI:0.5-1.1%)versus 1.8%(95%CI:0-30.2%),hookworm 14.9%(95%CI:13.8-16.1)versus 38.5%(95%CI:5.4-95.1%),and any STH 18.3%(95%CI:17.0-19.5%)versus 48.3%(CI:5.4-96.3%),respectively.In 2016,no district had high hookworm prevalence and four districts had moderate prevalence,compared with eight and four districts respectively in 2008.In 2016,the arithmetic mean hookworm egg count in all children examined was light:45.5 eggs per gram(EPG)of faeces,(95%CI:\35.96-55.07 EPG);three(0.08%)children had heavy infections and nine(0.25%)children had moderate infections.Conclusions:Sierra Leone has made considerable progress toward controlling STH as a public health problem among SAC.As LF MDA phases out(between 2017 and 2021),transition of deworming to other platforms and water and sanitation strategies need to be strengthened to maintain STH control and ultimately interrupt transmission.

New artificial boundary condition for saturated soil foundations

Anew artificial boundary model based on multi-directional transmitting and viscous-spring artificial boundary theories is proposed to absorb stress waves in a saturated soil foundation in dynamic analysis. Since shear waves （S-waves） are the same in a saturated soil foundation and a single-phase medium foundation, a tangential visco-elastic boundary condition for a single-phase medium foundation can also be used for saturated soil foundations. Thus, the purpose of the artificial boundary proposed in this paper is primarily to absorb two types of P-waves in a saturated soil foundation. The main idea is that the stress of the P-waves in the saturated soil foundation is decomposed into two types. The first type of stress, δra＇ is absorbed by the first artificial boundary. The second type of stress, δrb, is balanced by the stress generated by the second artificial boundary. Ultimately, both types of P-waves （fast-P-waves and slow-P-waves） are absorbed by the artificial boundary model proposed in this paper. In particular, note that the fast-P-waves and slow-P-waves are absorbed at the position of the first boundary. Thus, the artificial boundary model proposed herein can simultaneously absorb P-fast waves, P-slow waves and shear waves. Finally, a numerical example is given to examine the proposed artificial boundary model, and the results show that it is very accurate.

郑州地区土源性线虫感染监测检验结果分析

目的调查分析郑州地区土源性线虫感染率及流行特征情况,为制定防治措施提供参考。方法于2016—2022年对郑州登封市、管城回族区、上街区、中原区、金水区、二七区、惠济区、航空港区、新密市设置监测点进行监测,每个地区根据东、南、西、北、中划分为5个行政村,通过整群抽样方法每个行政村抽取3周岁以上的常住居民(外来居民住满1年以上、本地居民住满6个月及以上)至少200人,每个监测点至少1000人作为研究对象。所有监测对象采集粪便样本约30 g,利用改良加藤厚涂片法(一粪两检)检测土源性线虫虫卵情况,计算出土源性线虫感染情况,3~9周岁的儿童通过透明胶纸肛拭法增加蛲虫检测,分析土源性线虫感染各年感染情况及各虫卵感染情况,以及各人群土源性线虫感染情况。结果郑州共调查10437人,检出土源性线虫感染共32人,感染率为0.31%(32/10437),其中蛔虫3例,感染率为0.03%(3/10437),蛲虫29例,感染率为0.28%(29/10437),无钩虫、鞭虫感染。2016年土源性线虫感染率最高为1.33%(14/1052),2017年、2019年与2020年均未检出感染者,土源性线虫不同年份间感染率对比差异显著(χ^(2)=51.807,P<0.001)。登封市土源性线虫感染率最高1.33%(14/1052),管城回族区、中原区、金水区、二七区、惠济区、航空港区均未检出感染者,土源性线虫不同地区间感染率对比差异显著(χ^(2)=63.263,P<0.001)。男性土源性线虫感染率为0.20%(10/4947),女性感染率为0.40%(22/5490),土源性线虫不同性别间感染率对比无明显差异(χ^(2)=3.357,P=0.067);3~9岁年龄组土源性线虫感染率最高0.72%(11/1535),20~49岁年龄组感染率最低0.07%(1/1369),土源性线虫不同年龄组间感染率对比差异显著(χ^(2)=20.416,P=0.001);农民土源性线虫感染率最高0.52%(13/2478),医务人员及其他职业感染率最低0.14%(3/2091),土源性线虫不同职业间感染率对比无明显差异(χ^(2)=7.148,P=0.128);文盲/半文盲土源性线虫感染率最高0.80%(7/875),大专及以上学历人群感染率最低0.14%(4/2822),土源性线虫不同文化程度间感染率对比差异显著(χ^(2)=24.007,P<0.001)。结论蛲虫为郑州市地区土源性线虫病虫种,登封市为重点地区,女性、3~9岁儿童、农民、文盲/半文盲为高危人群,应加强郑州市重点地区及高危人群土源性线虫病防治管理。

2021—2023年邹城市土源性线虫病监测结果分析

目的:了解邹城市土源性线虫病感染现状,掌握其流行规律及影响因素,为相关部门制定防治策略提供科学依据。方法:2021—2023年选取邹城市常住居民3165人作为研究对象,每年收集常住居民的粪便样本,采用改良加藤厚涂片法检验。结果:在3165名常住居民中,检出土源性线虫病感染16人,总感染率为0.51%,其中鞭虫、蛔虫和蛲虫感染率分别为0.03%、0.03%和0.44%;不同年份土源性线虫病感染率比较,差异有统计学意义(χ^(2)=9.002,P<0.05);2021—2023年邹城市不同性别、不同年龄段、不同职业、不同文化程度人群土源性线虫病感染率比较,差异无统计学意义(P>0.05)。结论:邹城市已达到土源性线虫病传播控制与阻断标准,应加大健康教育宣传,提高人群对土源性线虫病的认识程度,开展重点人群驱虫防治工作,降低人群感染率,加强无害化厕所管理。完善人民健康促进政策,把保障人民健康放在优先发展的战略位置,从而进一步巩固阻断土源性线虫病防治成果。

基于NodeMCU的智能浇灌系统设计

当前,智能化技术不断发展,为了提升现代农田的智能化管理水平,设计以NodeMCU(节点微控制单元)作为中央控制器的智能浇灌系统,实现农田灌溉智能化。YL-69土壤湿度传感器用于检测土壤含水量,DHT11温湿度传感器用于检测环境温度和湿度,中央控制器负责数据的采集与处理,通过内置的ESP8266芯片连接Wi-Fi将数据无线传输至网页端进行实时监测与控制,并对比系统设置的阈值指标,反馈至微控制器,微控制器通过控制继电器打开水泵对土地浇灌,并且搭建数据库进行数据记录与分析。该系统结构简单,可靠性较高,可实现浇灌的无人化管理,具有重要的现实意义。

Assessment of albendazole efficacy against Ascaris lumbricoides at three sites of Andhra Pradesh,Odisha,and Kerala in India

Objective:To assess efficacy of albendazole against Ascaris(A.)lumbricoides among school-children at three sites of Rajahmundry,Sundergarh and Wayanad.Methods:Sites were selected based on soil-transmitted helminths prevalence,different sociocultural-geographical characteristics and operational feasibility.9-12 Years old children from 14 schools were included.The study was conducted in two rounds:baseline&follow up survey.All eligible children found positive for A.lumbricoides at baseline were administered supervised single tablet albendazole 400 mg under the National Deworming Day Initiative.During post-treatment follow-up survey,eligible children who provided second stool sample were included in the final analysis.Stool samples were examined using WHO recommended Kato-Katz technique.Efficacy was estimated based on cure rate(CR)and Fecal Egg Count Reduction Rate(FECRR)among children found positive in baseline and follow-up surveys.Results:328 Out of 625(52.5%)were found positive for A.lumbricoides in the baseline survey and 85 out of 178 samples(47.8%)during post-treatment follow-up survey.Overall,the estimated CR was 52.2%.FECRR(95%CI)for albendazole was 72.6%(79.2%-66.0%).The FECRR was highest in East Godaveri[89.7%(96.8%-82.6%)],followed by Sundergarh[86.4%(95.3%-77.5%)]and Wayanad[69%(81.7%-56.4%)].Conclusions:Our study confirmed overall reduction in FEC although with varying albendazole efficacy for A.lumbricoides infection at three different locations in India.However,these finding may be assessed in context of ongoing MDA under Filaria control program and further studies by in vivo as well as in vitro methods are required to reach to a conclusion on possible resistance if any.

2016—2022年山东省临沂市农村土源性线虫病感染状况调查

目的 了解临沂市2016—2022年土源性线虫病感染现状,为制定有针对性的防治策略和措施提供依据。方法 每个监测点采集1 000份粪便样本,采用改良加藤厚涂片法和透明胶纸肛拭法检测,计算土源性线虫感染率。采用SPSS 24.0软件进行统计学分析,感染率的差异比较采用χ^(2)检验。结果 2016—2022年临沂市土源性线虫监测点共调查16 361人,总感染率为2.15%(352/16 361)。土源性线虫感染率在不同县区、年龄组、职业、文化程度之间均存在显著差异(P<0.001)。结论 临沂市农村土源性线虫病人群感染率总体呈下降趋势,农村60岁人群以上老年人和学龄前儿童是土源性线虫防控的重点人群。

土源性线虫感染的化学治疗研究

在湖南省衡山县对常用驱虫药的疗效进行了研究。所用药物为阿苯达唑(400mg,单剂)、复方甲苯达唑(甲苯达唑100mg和左旋咪唑25mg bid×3d)、复方噻嘧啶(噻嘧啶与酚嘧啶各150mg,bid×2d)及噻嘧啶(10mg基质/kg,单剂)。给药后2wk的疗效显示前3种药物剂量组蛔虫感染者治愈率(CR)为97.5—100.0％,后者为80.9％;对钩虫感染者的CR分别为95.4％、78.6—100％、96.7％和83.3％,服药后4wk复查显示上述4个药物剂量组的CR无显著性差异。根据对鞭虫感染的CR来判断,以复方噻嘧啶为佳(89.3％),其次为复方甲苯达唑(64.6—83.8％),阿苯达唑再次之(28.2—42.6％),噻嘧啶无效。上述药物除噻嘧啶外,治疗鞭虫感染时虫卵减少率均显著。

福建省2006-2010年土源性线虫感染的监测

目的分析福建省土源性线虫感染及变化情况,为制定该地区土源性线虫病防治策略与评价防治效果提供科学依据。方法 2006-2010年对福建省漳州市浦南镇浦南村和邵武市鼓山镇鼓山村两个监测点,每年11月份收集3岁以上的常住居民粪便,采用改良加藤氏厚涂片法粪检肠道蠕虫卵(一送三检);同时对同村3～12周岁儿童用透明胶纸肛拭法检测蛲虫。另外,随机选择粪检阳性者的10户家庭,每年采集其居所附近的菜地、厕所周边、庭院和厨房等4种环境类型的土壤各1份,用改良饱和硝酸钠漂浮法检测蛔虫卵污染情况,用直接镜检法判定蛔虫卵活力。结果 2006-2010年,监测点居民土源性线虫感染率呈下降趋势,从2006年的45.3%(946/2087)下降至2010年的15.1%(226/1494),下降率为66.6%。其中监测点各年蛔虫和鞭虫感染者所占的比例均低于10%,而钩虫感染者则占75%～85%;钩虫感染者中,90%以上为农民,65.2%～85.5%为轻度感染。儿童蛲虫感染率呈下降趋势,从2006年的46.1%(140/304)下降至2010年的29.8%(36/121),下降率为35.4%,但仍维持在较高的感染水平。检测100户家庭不同环境类型的土壤400份,发现蛔虫卵有21份,其中1份蛔虫卵具有活力。结论 2006-2010年2个监测点人群土源性线虫感染率呈下降趋势,但居民钩虫和儿童蛲虫仍维持在较高的感染水平。

福建省土源性线虫感染流行现状分析

目的了解福建省土源性线虫人群感染现状。方法2007-2009年对全省9个地市采用分层整群随机抽样的方式确定调查点,调查对象为3周岁以上常住居民。用Kato-Katz法(一粪一检)粪检蛔虫、钩虫和鞭虫虫卵,分别计算3种虫卵的每克粪便虫卵数(EPG),同时收集调查者的性别、年龄和受教育程度等。并将本次调查结果与1992年和2003年的调查结果进行比较分析。结果本次共调查了9地市49县(市、区)185乡(镇)610村的93 833人。土源性线虫总感染率为10.14%(9 511/93 833),与1992年和2003年的比较,分别下降了86.88%和71.84%。蛔虫、钩虫和鞭虫的感染率分别为1.32%(1 234/93 833)、7.31%(6 863/93 833)和1.73%(1 622/93 833)。蛔虫、钩虫和鞭虫感染者的平均EPG分别为9 556、526和156。男性和女性感染率分别为9.48%(4 385/46 246)和10.77%(5 126/47 587),性别间差异有统计学意义(χ2=42.84,P<0.01);各年龄组间感染率差异有统计学意义(χ2=1 626,P<0.01);不同教育程度的人群感染率不同,教育程度越高,感染率越低(χ2=1 107,P<0.01)。结论福建省土源性线虫感染率呈下降趋势,但是在经济欠发达地区感染率仍然较高,钩虫感染率仍高于全国平均水平。

土源性线虫感染儿童智力水平和认知结构特征的研究

目的从认知结构不同维度对土源性线虫(钩虫、蛔虫和鞭虫)感染儿童的认知能力进行评估和鉴定,探讨土源性线虫感染儿童的认知结构特征。方法选取土源性线虫感染率较高的广西融水县白云乡、海南定安县龙州镇和新竹镇等3个乡镇的农村小学1 031名9～12岁儿童进行调查,采用改良加藤厚涂片法(Kato-Katz)检查钩虫、蛔虫和鞭虫的虫卵(一粪三检)。选取77例仅感染1种线虫者作为病例组,并以年龄、性别等与病例组相匹配的健康儿童39人为对照,共计1 16例,采用韦克斯勒儿童智力量表第4版(WISC-Ⅳ)进行认知能力诊断与测量评估。结果检出土源性线虫感染378例,感染率为36.7%(378/1 031);中、重度感染173例,感染率为16.8%(173/1 031)。土源性线虫感染儿童除知觉推理指数外,其总智商分数、言语理解指数、工作记忆指数和加工速度指数得分显著低于健康对照组(P<0.05)。中重度土源性线虫感染儿童在总智商分数(95.4)、言语理解指数(97.2)、工作记忆指数(84.6)和加工速度指数(91.1)均显著低于轻度感染组(分别为99.2、103.3、88.3和99.1)和健康对照组(分别为102.0、104.2、91.9和100.1)(P<0.05)。单纯钩虫感染组的工作记忆指数(83.7)显著低于蛔虫组(87.6)和鞭虫组(88.3)(P<0.05),单纯鞭虫感染组的加工速度指数(92.8)显著低于蛔虫组(97.3)和钩虫组(94.4)(P<0.05)。结论土源性线虫感染儿童的智力水平在正常范围,但处于较低或边缘状态,言语理解、工作记忆和加工速度等方面的认知功能存在不足,尤其是中重度土源性线虫感染影响儿童智力水平和认知功能。