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.

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.

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.

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.

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.

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。

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。

2014年传染病相关热点回顾

本文公布了中国大陆2014年法定传染病发病情况,并重点介绍了2014年全球发生的各重要传染病(埃博拉病毒病、登革热、禽流感、肠道病毒D68感染、中东呼吸综合征、疟疾、基孔肯雅热、结核病、肝病、麻疹和土源性蠕虫病)的流行概况及其在诊断、治疗、预防和研究方面的相关进展。

鄱阳湖区人群土源性线虫感染与土壤污染状况调查

目的了解鄱阳湖区进贤县4个村土壤中土源性线虫卵污染情况及其与人群感染率的关系。方法在4个村131户农户的庭院、客厅、厕所、菜园4处采集土壤,土壤寄生虫卵检查采用饱和硫酸镁离心漂浮法,人群土源性线虫检查采用Kato-Katz法。结果4个村共调查1210人,蛔虫、鞭虫、钩虫感染率分别为26.26%、65.26%、1.74%。土壤样本共检查131户,蛔虫卵、鞭虫卵、钩虫卵检出率分别为58.02%、77.86%、3.82%。相关分析表明,4个村人群土源性线虫感染率与土样中土源性线虫卵检出率非常显著正相关(γ=0.995,P<0.01),其中人群蛔虫感染率与土样蛔虫卵检出率显著正相关(γ=0.954,P<0.05),人群鞭虫感染率与土样鞭虫卵检出率非常显著正相关(γ=0.991,P<0.01)。131户农户的菜园、厕所、庭院、客厅的蛔虫卵检出率依次为48.86%、47.53%、45.04%、34.35%,鞭虫卵检出率依次为66.40%、74.23%、54.20%、45.04%。蛔虫卵、鞭虫卵的每克土壤虫卵数均以菜园和厕所较高。土样中还查到其他寄生虫卵和成虫。结论鄱阳湖区进贤县的4个村土壤中土源性线虫卵检出率与人群感染率之间非常显著相关。

不同化疗方案控制土源性线虫病传播的效果观察

目的 探讨土源性线虫病高度流行区经济、有效、易行的化疗策略。 方法 在 3个自然村随机采用 3种全民化疗方案 ,即首次化疗后 ,每隔 3个月、6个月和 12个月重复化疗 1次 ,药物采用噻嘧啶 10 mg/ kg体重 ,顿服 ,对控制蛔、钩、鞭虫病的效果进行了比较分析。 结果 1年后 ,3、6、12个月间隔服药村的居民蛔虫感染率分别从 4 9.5 8%下降至 2 1.6 7%(P<0 .0 1)、4 4 .2 6 %下降至 2 5 .88% (P<0 .0 1)、5 5 .5 5 %下降至 39.38% (P<0 .0 1) ;钩虫感染率分别从 12 .2 9%下降至1.4 8% (P<0 .0 1)、18.0 3%下降至 2 .5 6 % (P<0 .0 1)、8.6 1%下降至 6 .5 6 % (P>0 .0 5 )。化疗后 ,3和 6个月间隔服药村之间蛔虫及钩虫的感染率差异无显著性 (P>0 .0 5 ) ,12个月间隔服药村蛔虫感染率显著高于上述 2个村 ,鞭虫阳性率化疗前后各村均无显著性变化。 结论 每隔 6个月化疗 1次对控制蛔虫、钩虫病的流行较为经济。

Reduced efficacy of single-dose albendazole against Ascaris lumbricoides, and Trichuris trichiura, and high reinfection rate after cure among school children in southern Ethiopia: a prospective cohort study

Background Mass drug administration(MDA)program of albendazole to at-risk populations as preventive chemo-therapy is the core public health intervention to control soil-transmitted helminths(STHs).Achieving this goal relies on drug effectiveness in reducing the parasite reservoirs in the community and preventing reinfection.We assessed the effcacy of albendazole against STH parasite infection and reinfection status after cure.Methods A total of 984 schoolchildren infected with at least one type of STH parasite(hookworm,Ascaris lumbri-coides,Trichuris trichiura)in southern Ethiopia were enrolled and received albendazole and praziquantel in MDA campaign conducted from January to March 2019.Stool exams at week-4 and at week-8 of post-MDA were done using Kato Katz technique.The primary outcome was effcacy assessed by cure rate(CR)and fecal egg reduction rates(ERRs)at four weeks of post-MDA.The secondary outcome was reinfection status defined as parasite egg positivity at eight weeks among those who were cured at 4 weeks of post-MDA.Group comparisons in CR and related factors were assessed with chi-square or Fisher's exact tests.Predictors of CR were examined through univariate and multi-variate regression analyses.Results The overall CR and ERR for hookworm infection were 97.2%(95%CI:94.6-99.4)and 97.02%,respectively.The overall CR and ERR for A.lumbricoides were 71.5%(95%CI:68.3-74.6)and 84.5% respectively.The overall CR and ERR and for T.trichiura were 49.5%(95%CI:44.8-54.2)and 68.3%,respectively.The CR among moderate T.trichiura infec-tion intensity was 28.6%.Among children cured of hookworm,A.lumbricoides and T.trichiura at week 4 post-MDA,4.6%,18.3% and 52.4% became reinfected at week-8 post-MDA,respectively.Significantly lower CR(36.6%)and higher reinfection after cure(60.6%)among A.lumbricoides and T.trichiura coinfected children than A.lumbricoides only(CR=69.6%,reinfection rate=15.1%)or T.trichiura only infected children(CR=55.6%,reinfection rate=47.1%)was observed.Pre-treatment coinfection with≥two types of STH parasites was significantly associated with re-infec-tion after cure.Conclusion Albendazole MDA is efficacious against hookworm but has reduced efficacy against A.lumbricoides and is not effective against T.trichiura.The low drug efficacy and high reinfection rate after cure underscore the need for alternative treatment and integration of other preventive measures to achieve the target of eliminating STHs as a public health problem by 2030.

2016-2019年广西灵山县土源性线虫感染监测分析

目的了解灵山县土源性线虫流行情况及其影响因素,评价防治效果,为制定今后防治策略与措施提供科学依据。方法2016-2019年在灵山县按照地理方位将全县划分为东、西、南、北、中5个片区,在每个片区随机抽取1个乡镇的1个行政村为纵向监测点,连续4年开展土源性线虫病监测,监测对象为≥3岁常住居民,每个点约200人,共约1000人,收集监测对象粪样,用改良加藤厚涂片法一送二检,检测寄生虫虫卵。结果2016-2019年灵山县共调查4363人,土源性线虫总感染率为1.08%(47/4363),其中钩虫、蛔虫和鞭虫的感染率分别为0.66%(29/4363)、0.30%(13/4363)、0.11%(5/4363)。不同年度感染率差异有统计学意义(X^(2)=10.387,P<0.05),总体呈下降趋势(X^(2)=8.045,P<0.05)。烟墩镇感染率最高为2.75%(26/945),人群感染率最高的是幼托儿童2.55%(11/431)。各虫种均以轻度感染为主,占总感染数89.36%(42/47)。钩虫感染主要集中于70岁及以上年龄组,鞭虫感染率较高为60~69岁年龄组,蛔虫则在0~9岁年龄组感染较高。结论灵山县土源性线虫感染率已降至较低水平,有地区和人群的分布差异,提示要针对不同地区、不同人群制定精准的防控措施。

2016-2019年江西省土源性线虫病国家监测点人群感染情况分析

目的了解2016-2019年江西省土源性线虫病国家监测点人群感染情况,为全省制订土源性线虫病防治策略、评价防治效果提供科学依据。方法 2016-2019年在全省11个县(市)设立国家监测点,并按照《全国肝吸虫病和土源性线虫病监测方案(试行)》开展监测。监测点以县为单位按地理方位划分为东、西、南、北、中5个片区,每个片区抽取1个乡镇的1个行政村开展监测,监测点4年固定不变。每个行政村整群抽取3周岁以上常住居民不少于200人,每个监测点不少于1 000人。收集被调查者粪样,采用改良加藤厚涂片法(一粪二检)检测土源性线虫感染情况,计算感染率和感染度等指标;钩虫卵阳性粪样以试管滤纸培养法进行钩蚴培养,鉴定钩虫种类。感染率间比较采用卡方检验。每个行政村随机抽取5户家庭,每户采集1份田地或菜园的土样,其中350 g用于钩蚴检测,50 g用于人蛔虫卵检测。采用5%盐水进行土壤钩蚴镜检鉴定;用饱和硝酸钠漂浮法检测土壤中人蛔虫卵。结果11个监测点生产方式均以农业为主,饮用水以自来水和井水为主。2016-2019年无害化厕所覆盖率分别为78.4%(30 443/38 817)、 80.7%(32 856/40 723)、 85.6%(35 301/41 258)和91.0%(37 964/41 730),不同年份间差异有统计学意义(P <0.01)。2016-2019年11个监测点人群土源性线虫感染率分别为1.6%(175/11 126)、 1.4%(160/11 203)、 0.8%(91/11 183)和1.3%(151/11 197);感染率总体呈下降趋势,2019年较2016年下降了14.1%,不同年份间差异有统计学意义(P <0.01)。4年南丰县人群土源性线虫感染率分别为4.7%(48/1 016)、 3.8%(39/1 034)、 2.6%(27/1 028)和7.4%(75/1 010),均高于其他县(P <0.01)。人群钩虫感染率呈现年间波动,从2016年的1.0%(116/11 126)降至2018年0.6%(70/11 183),2019年再升至1.0%(112/11 197),各年度间差异有统计学意义(P <0.01)。除2016年外,各年度女性土源性线虫和钩虫感染率均高于男性。4年钩虫感染者中,美洲钩虫感染构成比分别为92.2%(71/77)、 91.0%(61/67)、 97.8%(44/45)和91.8%(89/97),其次为混合感染,单纯十二指肠钩虫感染较少。人群蛔虫感染率总体呈下降趋势,从2016年的0.5%(53/11 126)下降至2019年的0.3%(29/11 197),各年度间差异有统计学意义(P <0.01)。4年鞭虫感染率分别为0.1%(6/11 126)、 0.1%(14/11 203)、 0.1%(9/11 183)和0.1%(10/11 197)。4年土壤样本蛔虫卵检出率分别为9.1%(25/275)、 1.8%(5/275)、 1.8%(5/275)和1.5%(4/275),各年度间差异有统计学意义(P <0.01)。土壤中人蛔虫卵与钩蚴检出率均呈逐年下降趋势。结论江西省人群土源性线虫感染率与中、重度感染者比例总体逐年下降,呈低度流行态势。钩虫仍是今后土源性寄生虫病防治的重点虫种,南丰县是今后防控的重点地区。

江西省2016-2019年土源性线虫病时空聚集性分析

目的 应用空间流行病学方法分析江西省土源性线虫病流行特征,为控制土源性线虫病提供科学依据。方法 收集江西省2016—2019年土源性线虫病监测资料,进行描述性流行病学分析,并应用空间自相关和热点分析方法、回顾性时空扫描统计量方法对土源性线虫病传播风险热点和聚集区域进行空间聚集性分析。结果 全省人群4年间土源性线虫感染率分别为1.32%(947/71 766)、1.14%(803/70 547)、0.87%(604/69 507)和0.90%(628/69 620),不同年份差异有统计学意义(P<0.01);钩虫感染率分别为0.65%(466/71 766)、0.64%(450/70 547)、0.48%(336/69 507)和0.52%(362/69 620),不同年份差异有统计学意义(P<0.01);蛔虫感染率分别为0.55%(393/71 766)、0.41%(287/70 547)、0.32%(221/69 507)和0.32%(225/69 620),不同年份差异有统计学意义(P<0.01);鞭虫感染率分别为0.17%(125/71 766)、0.10%(74/70 547)、0.08%(57/69 507)和0.07%(49/69 620),不同年份差异有统计学意义(P<0.01)。全局空间自相关分析结果显示钩虫感染率2016年,鞭虫感染率2016、2018与2019年Moran’s I值有统计学意义(P<0.05)。局部热点区域探测、SaTScan和FleXScan两种时空扫描分析方法结果显示,各年度各虫种感染均存在高值聚集区域。结论 全省2016—2019年人群土源性线虫、钩虫、蛔虫与鞭虫感染率均呈下降趋势,且存在时空聚集性。因此,在制定防控策略时应有针对性地考虑时空分布特征。

2013-2016年合江县土源性线虫监测结果分析

目的了解合江县土源性线虫感染状况和流行规律,为制定土源性线虫感染防制措施提供科学依据。方法采用改良加藤厚涂片法,一粪三检,查钩虫、蛔虫、鞭虫卵和透明胶纸肛试子法查蛲虫卵对监测点的常住居民进行土源性线虫感染情况进行监测。率的比较采用χ^2检验。结果2013-2016年间,合江县土源性线虫平均感染率为11.41%,其中蛲虫的平均感染率最高(χ^2=634.67,P<0.05);土源性线虫感染总感染率分别为13.80%、10.80%、9.15%和11.90%,整体未呈现显著趋势(χ^2=2.69,P>0.05)。女性的鞭虫感染率(0.78%)高于男性(0.26%)(χ^2=5.17,P<0.05);土源性线虫总感染率随着年龄增加呈增长趋势(χ趋势2=127.97,P<0.05);非学龄儿童和农民的土源性线虫、钩虫感染率较高,学生较低(P<0.05),非学龄儿童和学生蛔虫感染率较高,农民较低(P<0.05);土源性线虫的总感染率随着文化水平的提高总体呈下降趋势(P<0.05)。结论2013-2016年合江县土源性线虫感染率总体无下降趋势,不同年龄、性别、文化程度土源性线虫感染率不同。

单次和双次阿苯达唑治疗土源性线虫感染的疗效观察

目的观察单次和双次阿苯达唑治疗人体土源性线虫感染的疗效。方法2015年10月—2016年1月,选择云南省西双版纳州勐海县布朗山乡5所小学2~6年级的小学生进行基线调查,连续2 d收集粪样,每人每天1份,每份粪样采用Kato-Katz法制作3张加藤片镜检,结果为阳性(蛔虫、钩虫、鞭虫单一或混合感染)的学生接受阿苯达唑治疗(一次口服400 mg)。服药后3 d连续2 d收集粪样并镜检。4周后同一批学生再次服用阿苯达唑片剂400 mg,3 d后连续2 d收集粪样并镜检。2次服药后均同时开展问卷调查,统计不良反应情况。经2次服药后仍然阳性的学生再服用阿苯达唑片剂治疗1次。将5所小学按行政村归纳,统计不同行政村鞭虫感染治疗疗效。率的比较采用卡方检验。结果5所学校共调查438人,土源性线虫感染率82.19%(360/438)。男生感染率为79.19%(175/221),女生为85.25%(185/217),差异无统计学意义(χ2=2.754,P>0.05);布朗族、拉祜族、哈尼族、其他民族学生土源性线虫感染率分别为89.79%(299/333)、90.57%(48/53)、21.43%(9/42)、4/10(χ2=133.781,P<0.05);2~6年级学生土源性线虫感染率分别为73.97%(54/73)、90.38%(94/104)、73.56%(64/87)、87.50%(28/32)、84.51%(120/142)(χ2=13.700,P<0.05)。蛔虫、钩虫、鞭虫感染率分别为52.51%(230/438)、35.39%(155/438)、73.29%(321/438),其中第1次服药后蛔虫、钩虫、鞭虫感染治愈率分别为94.24%(180/191)、63.64%(77/121)、2.64%(7/265),第2次服药后蛔虫、钩虫、鞭虫感染治愈率分别为98.77%(161/163)、91%(91/100)、6.33%(14/221)。蛔虫、钩虫、鞭虫感染者服用1、2次阿苯达唑治愈率差异均有统计学意义(χ2=5.107、22.487、3.976,P<0.05)。蛔虫、钩虫、鞭虫轻、中、重度感染者两次服药后治愈率差异均无统计学意义(第一次服药χ2=3.218、3.930、4.050,P>0.05;第二次服药χ2=1.745、1.902、0.329,P>0.05)。第1次服药后觉得吞药片困难、头晕、恶心、腹泻、呕吐等不良反应的发生率依次为11.47%(39/340)、10.88%(37/340)、16.76%(57/340)、7.65%(26/340)、1.47%(5/340)。第2次服药不良反应发生率接近第1次,两次服药各项不良反应发生率差异均无统计学意义。按照学校所在行政村分析,第2次服药后吉良小学感染鞭虫的学生治愈率为12.68%(9/71),高于曼囡小学(3.60%,4/111)(χ2=5.374,P<0.05)。结论阿苯达唑单次疗法对蛔虫感染有较好疗效;双次疗法对蛔虫和钩虫的驱虫效果均更好,且不增加不良反应的发生率。用阿苯达唑治疗中、重度的蛔虫、钩虫感染者无需增加剂量。阿苯达唑对鞭虫治疗效果较差,不宜单独使用阿苯达唑治疗鞭虫感染者。

8个干预示范区停止干预措施后土源性线虫病的控制现状评价

目的评价8个寄生虫病综合防治示范区停止干预措施后,土源性线虫病的控制现状。方法在2009年综合防治措施停止后,于2011-2015年的9-11月调查贵州省开阳县、海南省屯昌县、江西省贵溪市、安徽省桐城市、湖南省岳阳县、云南省祥云县、广西壮族自治区容县和四川省丹棱县等8个示范区的人群土源性线虫感染率、健康知识知晓率、无害化厕所和自来水普及情况,对不同时间、地区、性别、年龄、虫种等的人群土源性线虫感染率进行χ~2检验。结果2011-2015年,8个示范区人群土源性线虫总感染率分别为6.1%(490/8 005)、5.8%(474/8 146)、5.5%(447/8 066)、5.8%(477/8 164)和4.0%(305/7 688),其中钩虫(Ancylostoma sp.)的感染率由3.8%(303/8 005)降至2.3%(177/7 688)(P<0.05),蛔虫(Ascaris lumbricoides)感染率由1.6%(125/8 005)降至1.0%(78/7 688)(P<0.05),鞭虫(Trichuris trichiura)感染率由1.1%(84/8 005)降至0.3%(24/7 688)(P<0.05)。8个示范区中,海南屯昌示范区的土源性线虫感染率在2011-2015年均最高,分别为19.2%(195/1 015)、19.7%(209/1 063)、20.6%(215/1 046)、22.6%(235/1 038)和11.2%(114/1 022)。5~9岁年龄组的蛔虫感染率在2011-2014年均最高,分别为2.9%(23/797)、2.4%(17/698)、2.0%(16/800)、1.2%(9/735);60岁以上年龄组的钩虫感染率在2011-2015年均最高,分别为6.2%(76/1 231)、5.1%(67/1 328)、6.0%(88/1 476)、6.2%(118/1 894)、2.7%(54/2 032)。男性土源性线虫感染率为5.5%(1 090/19 805),女性为5.3%(1 050/19 904),两者差异无统计学意义(P>0.05)。2011-2015年,人群卫生知识行为问卷合格率分别为93.2%(1 129/1 211)、94.9%(1 142/1 203)、94.1%(1 134/1 205)、92.3%(973/1 054)和94.9%(854/900)。自来水普及率由2011年的33.2%(187/564)上升至2015年的59.4%(209/352);无害化厕所普及率由2011年的71.3%(402/564)上升至2015年的77.3%(272/352)。结论2009年示范区综合防治措施停止后,防治效果仍然维持在有效控制状态,表明原先的措施取得了可持续的效果。

福建省2015年人体土源性线虫感染调查分析

目的了解福建省人群土源性线虫感染流行现状,为制定防治对策提供科学依据。方法于2014-2015年根据生态区、经济水平、地理方位进行分层整群随机抽样,选择福建省10个地市25县63个调查点。采用改良加藤厚涂片法,对受检者进行粪检(一粪两检),检查肠道蠕虫卵感染情况。透明胶纸肛拭法检查12岁以下儿童蛲虫卵。感染率间差异采用卡方检验。结果共调查17 090人,检出土源性线虫感染560例,感染率为3.28%,与1992年第一次(77.30%, 41 290/53 416)和2003年第二次(36.01%, 7 300/20 195)调查的结果比较,分别下降了95.76%和90.89%。3种土源性线虫中,钩虫感染率最高,为3.03%(518/17 090),鞭虫和蛔虫的感染率分别为0.20%(34/17 090)和0.05%(8/17 090)。各地市中,三明的感染率最高,为9.21%(154/1 673);宁德最低,为0.20%(3/1 514)。女性感染率为3.72%(325/8 728),高于男性的2.81%(235/8 362)(P <0.01)。浙闽山地丘陵生态区的感染率为3.52%(271/7 701),滇、桂、粤中部鄄闽南山地丘陵生态区为3.08%(289/9 389),二者差异无统计学意义(P> 0.05)。不同年龄组人群感染率随着年龄的增大总体呈上升趋势,其中3～9年龄组人群的感染率最低,为0.43%(9/2 076); 60～69年龄组人群的感染率最高,为7.34%(180/2 453);不同年龄组差异有统计学意义(P <0.01)。职业分布以农民的感染率最高,为4.33%(524/12 095);不同职业间差异有统计学意义(P <0.01)。文化程度以小学文化人群感染率最高,为4.09%(322/7 875);不同文化程度间差异有统计学意义(P <0.01)。检查12岁以下儿童共3 472人,检出蛲虫感染205例,感染率为5.90%。结论福建省土源性线虫感染率呈持续下降趋势,处于较低流行水平,但农民群体、儿童和老年人为重点防治人群,钩虫和蛲虫为重点防治虫种。