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Objective To investigate the prevalence and influencing factors of soil-transmitted nematode infections in Ningbo City from 2016 to 2021, so as to provide insights into the development of targeted control measures against soil-transmitted nematodiasis. Methods Permanent residents at ages of 3 years and older were sampled in Ningbo City using a multi-stage sampling method each year during the period from 2016 to 2021. Soil-transmitted nematode eggs were detected in stool samples using a modified Kato-Katz thick smear method (two slides for each stool sample), and Enterobius vermicularis eggs were additionally identified among children at ages of 3 to 12 years using the adhesive cellophane-tape perianal swab method. The time- and regions-specific prevalence of soil-transmitted nematode infections was calculated, and the factors affecting hookworm infections were identified using a multivariate logistic regression model. Results A total of 11 573 person-times were detected for soil-transmitted nematode infections in Ningbo City from 2016 to 2021, and 296 egg-positives were detected, with a mean prevalence rate of 2.56% [95% confidential interval (CI): (2.28%, 2.87%)]. Hookworm was the predominant species of soil-transmitted nematode among egg-positives in Ningbo City (98.31%, 291/296), and there was a significant difference in the prevalence of hook-worm infections among years (χ2 = 190.27, P < 0.01). The highest prevalence of hook-worm infections was observed in Ninghai County (4.06%), and there was a region-specific prevalence rate of hookworm infection in Ningbo City (χ2 = 148.43, P < 0.01). Multivariate logistic regression analysis showed that elderly residents at ages of over 60 years [odds ratio (OR)= 1.94, 95% CI: (1.07, 3.54), P < 0.05], males [OR = 2.19, 95% CI: (1.72, 2.80), P < 0.01], farmers [OR = 6.94, 95% CI: (3.37, 14.29), P < 0.01] and residents with a low education level [illiteracy or semi-illiterate: OR = 3.82, 95% CI: (1.56, 9.35), P < 0.05; primary school: OR = 2.70, 95% CI: (1.11, 6.59), P < 0.05] were at a higher risk for hookworm infections. Conclusions The overall prevalence of soil-transmitted nematode infections was low among residents in Ningbo City from 2016 to 2021. The surveillance and health education for human hookworm disease remain to be reinforced among male farmers with a low education level at ages of over 60 years in Ninghai County.
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Objective To understand the prevalence of soil-transmitted nematode infections in Yancheng City from 2016 to 2020, so as to provide insights into the development of the scheme for further soil-transmitted nematodiasis surveillance. Methods Soil-borne nematode infections were detected using the modified Kato-Katz method (two slides for one sample) among the permanent residents living in Yancheng City from 2016 to 2020, and Enterobius vermicularis infection was additionally detected among children at ages of 12 years and lower using the adhesive cellophane-tape perianal swab method. The prevalence and intensity of human soil-borne nematode and E. vermicularis infections were descriptively analyzed. Results A total of 51 259 person-time residents were detected for soil-borne nematode infections in Yancheng City from 2016 to 2020, and 48 egg-positives were identified, with a 0.09% prevalence. The soil-borne nematodes infecting residents included Ascaris lumbricoides, hookworm and Trichuris trichiura, with 0.04%, 0.05% and 0.002% prevalence rates of infections, and all infections were mild. There was a region-specific prevalence of soil-borne nematode infections in Yancheng City (χ2 = 18.21, P = 0.02), with the highest prevalence seen in Funing County (0.21%), while no infections were detected in Dafeng District for five successive years. The overall prevalence of E. vermicularis infections was 0.22% among children at ages of 12 years and lower in Yancheng City. Conclusions The prevalence of soil-borne nematode infections appears a gradual decline in residents living in Yancheng City from 2016 to 2020, and is at an extremely low level. Further surveillance of soil-transmitted nematodiasis requires to be intensified targeting key regions and populations to consolidate the control achievements.
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Objective To investigate the prevalence of soil-transmitted nematode human infections in Jurong City from 2016 to 2020, so as to provide the scientific evidence for formulating the control strategy. Methods During the period from 2016 to 2020, the permanent residents at ages of over 3 years living in Jurong City were selected as the study subjects. Stool samples were collected for the detection of soil-transmitted nematode eggs using the modified Kato-Katz thick smear method (two detections for one stool sample), and the species of hookworm was identified in stool-positive stool samples using the culture method. The prevalence and intensity of soil-transmitted nematode infections were calculated, and the change of the infection prevalence among years was examined using the Cochran-Armitage test for trend. Results A total of 10 011 people-time populations were detected for soil-transmitted nematode infections in Jurong City from 2016 to 2020, and 56 egg-positives were identified, with mean prevalence of 0.56%. The prevalence of soil-transmitted nematode human infections appeared a tendency towards a decline year by year in Jurong City (χ2trend = 5.15, P < 0.01). The mean prevalence of hookworm, Ascaris lumbricoides and Trichuris trichiura infections was 0.44%, 0.11% and 0.20% in Jurong City from 2016 to 2020, respectively, and individuals with hookworm infections accounted for 78.57% of all cases with soil-transmitted nematode infections. Single parasite (98.21%) and mild infection were pre-dominant in individuals with soil-transmitted nematode infections, and no multiple infections were seen after 2016. Conclusions The prevalence of human soil-transmitted nematodiasis is low in Jurong City. Based on reinforcement of soil-transmitted nematodiasis surveillance, an increase in the health education investment is required to consolidate the control achievements.
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Soil-transmitted nematodiasis was once widely prevalent in Jiangsu Province, which seriously threatened human health and hindered socioeconomic development. The control efforts over decades resulted in a remarkable decline in the prevalence of soil-transmitted nematode human infections in Jiangsu Province, with a reduction from 59.32% in 1989 to 0.12% in 2019, and the human prevalence remains at < 0.5% since 2013. Since 1987, an integrated strategy has been adopted for the control of soil-transmitted nematodiasis in Jiangsu Province; however, the core interventions varies at different stages, which mainly include deworming, water and sanitation service improvement, health education, and monitoring and assessment. The criteria of effective soil-transmitted nematodiasis control had been achieved in all epidemic counties (districts) of Jiangsu Province by 2019. Further actions to strengthen health education and monitoring and implement precision control measures are required to consolidate the achievements of soil-transmitted nematodiasis control and eliminate the harm of soil-transmitted nematodiasis to humans. This review summarizes the epidemiology, control progress and evolution of control strategy of soil-transmitted nematodiasis in Jiangsu Province.
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Objective To investigate the related factors of soil-transmitted nematode infections in Chongqing City, so as to provide the basis for scientific prevention and treatment of the infections. Methods From 2011 to 2015, the stool samples of residents of the surveillance sites in Chongqing City were collected every year, and the soil-transmitted nematode eggs were examined by the modified Kato-Katz thick smear method (three smears for a single stool sample). The respondents were surveyed by questionnaires, and the factors affecting soil-transmitted nematode infections were identified. Results The prevalence of human soil-transmitted nematode infections were 6.44%, 7.30%, 6.85%, 6.93% and 5.56% in Chongqing City from 2011 to 2015, respectively. The more unclean drinking water and the lower frequency of washing hands after using the toilet were the risk factors for Ascaris lumbricoides infection. The more harmless toilets, the higher level of fertilizer application, the lower frequency of drinking raw water, and the lower frequency of food without washing were the protective factors for A. lumbricoides infection. Conclusions The local soil-transmitted nematode infections are at a low epidemic level in Chongqing City, and it is necessary to ad-here to the classified guidance, comprehensive prevention and further monitoring on the basis of health education, water and toilet improvement, and environmental sanitation improvement in order to consolidate the prevention and control achievements.
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Objective To understand the current situation of soil-transmitted nematode infections and influencing factors of pupils in rural areas of Yi Ethnicity in Butuo County, Sichuan Province, so as to provide the evidence for the prevention and control of soil-transmitted nematode infections. Methods In 2016, the pupils of 2 villages in Butuo County were selected by the multi-stage random sampling method, and the relevant information was obtained by questionnaires, including social demographic information, diet and hygiene habits and acknowledge of parasitic disease prevention. The soil-transmitted nematode infections were examined by Kato-Katz technique. The results were statistically analyzed by the single factor analysis and multivariate logistic regression methods. Results A total of 160 pupils were investigated in this survey. The soil-transmitted nematodes included Ascaris lumbricoides, Trichuris trichiura and hookworm. The overall infection rate was 89.38%, and the multi-infection rate was 54.55%. The infection rates of A. lumbricoides and T. trichiura were higher. The infection densities were mild (75.68%) or moderate (22.97%). The logistic regression analysis showed that the protective factor of soil-transmitted nematode infections was the knowledge about correct diet and health habits notified by teachers (OR = 0.67), but the risk factor was drinking unboiled water (OR = 19.26). Conclusions The infection rate of nematodes is still high in the pupils in rural areas of Yi Ethnicity in Butuo County, Sichuan Province. Therefore, we should strengthen the prevention and control of soil-transmitted nematode infections, especially A. lumbricoides and T. trichiura infections, and mostly develop the teachers’function in health education.
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Objective To understand the current situation of soil-transmitted nematode infections and influencing factors of pupils in rural areas of Yi Ethnicity in Butuo County, Sichuan Province, so as to provide the evidence for the prevention and control of soil-transmitted nematode infections. Methods In 2016, the pupils of 2 villages in Butuo County were selected by the multi-stage random sampling method, and the relevant information was obtained by questionnaires, including social demographic information, diet and hygiene habits and acknowledge of parasitic disease prevention. The soil-transmitted nematode infections were examined by Kato-Katz technique. The results were statistically analyzed by the single factor analysis and multivariate logistic regression methods. Results A total of 160 pupils were investigated in this survey. The soil-transmitted nematodes included Ascaris lumbricoides, Trichuris trichiura and hookworm. The overall infection rate was 89.38%, and the multi-infection rate was 54.55%. The infection rates of A. lumbricoides and T. trichiura were higher. The infection densities were mild (75.68%) or moderate (22.97%). The logistic regression analysis showed that the protective factor of soil-transmitted nematode infections was the knowledge about correct diet and health habits notified by teachers (OR = 0.67), but the risk factor was drinking unboiled water (OR = 19.26). Conclusions The infection rate of nematodes is still high in the pupils in rural areas of Yi Ethnicity in Butuo County, Sichuan Province. Therefore, we should strengthen the prevention and control of soil-transmitted nematode infections, especially A. lumbricoides and T. trichiura infections, and mostly develop the teachers’function in health education.
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Objective To investigate the related factors of soil-transmitted nematode infections in Chongqing City, so as to provide the basis for scientific prevention and treatment of the infections. Methods From 2011 to 2015, the stool samples of residents of the surveillance sites in Chongqing City were collected every year, and the soil-transmitted nematode eggs were examined by the modified Kato-Katz thick smear method (three smears for a single stool sample). The respondents were surveyed by questionnaires, and the factors affecting soil-transmitted nematode infections were identified. Results The prevalence of human soil-transmitted nematode infections were 6.44%, 7.30%, 6.85%, 6.93% and 5.56% in Chongqing City from 2011 to 2015, respectively. The more unclean drinking water and the lower frequency of washing hands after using the toilet were the risk factors for Ascaris lumbricoides infection. The more harmless toilets, the higher level of fertilizer application, the lower frequency of drinking raw water, and the lower frequency of food without washing were the protective factors for A. lumbricoides infection. Conclusions The local soil-transmitted nematode infections are at a low epidemic level in Chongqing City, and it is necessary to ad-here to the classified guidance, comprehensive prevention and further monitoring on the basis of health education, water and toilet improvement, and environmental sanitation improvement in order to consolidate the prevention and control achievements.
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Objective To understand the epidemic trend of soil-transmitted nematodiasis in Zhenjiang City from 2006 to 2018, so as to provide evidence for formulating targeted control measures. Methods The permanent residents at ages of 3 years and greater and the immigrants who had lived in Zhenjiang City for more than one year were selected as the study subjects. Fecal samples were collected, and the soil-transmitted nematode eggs were detected in fecal samples with the modified Kato-Katz technique (three smears from one stool sample), while the children at ages of 12 years and lower were tested for Enterobius vermicularis eggs using the adhesive cellophane-tape perianal swab method. The prevalence and intensity of parasitic infections were estimated in Zhenjiang City each year from 2006 to 2018, and the data pertaining to the deworming for soil-transmitted nematode infections were collected during the study period. Results A total of 202 880 person-times were subjected to stool examinations in Zhenjiang City from 2006 to 2018, and 946 persons were detected with soil-transmitted nematode infections, with a mean prevalence of 0.47%. The overall prevalence of human soil-transmitted nematode infections appeared a decline tendency (P < 0.01), with a reduction from 1.10% in 2006 to 0.11% in 2018, and there was a region-specific overall prevalence (P < 0.01), with the highest prevalence seen in Runzhou District (1.65%) and the lowest detected in New District (0.04%). The mean prevalence of human Ascaris lumbricoides, hookworm and Trichuris trichiura infections was 0.33%, 0.09% and 0.04% in Zhenjiang City, respectively, and showed a decline tendency year by year from 2006 to 2018 (P < 0.01). Among all infections, mild infections were predominant. During the period from 2006 through 2018, a total of 45 427 children were examined in Zhenjiang City from 2006 to 2018, and 145 children were positive for E. vermicularis infections, with a mean prevalence of 0.32%. The prevalence of E. vermicularis infections decreased from 1.33% in 2006 to 0.22% in 2018 in children, and the overall prevalence appeared a decline tendency (P < 0.01). A single parasite infection was predominant in soil-transmitted nematode infections (97.46%), and mixed infection of two parasites were mainly detected before 2007. A total of 535 089 person-times received deworming in Zhenjiang City from 2006 to 2018, and the rate of adverse events was 0.002%. Conclusions Currently, the soil-transmitted nematode infection is at a low level in Zhenjiang City, and the overall prevalence of soil-transmitted nematode infections shows a decline tendency year by year. The surveillance and health education of soil-transmitted nematodiasis should be further intensified to consolidate the control achievements.
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Objective To establish an evaluation system for the field assessment of the Kato-Katz technique in detecting soiltransmitted nematodes, so as to provide insights into the field application of the Kato-Katz technique. Methods The initial evaluation indicators were determined through literature search, brainstorming and expert consultation. The evaluation indicatorswere improved and the weight of each indicator was decided through three rounds of expert consultation by using the Delphimethod. In addition, the expert authority coefficient and the coordination coefficient of each indicator were calculated at eachround of expert consultations. Results The recovery rates of the questionnaire were 100.00%, 100.00% and 89.29% at the firstto the third round of the expert consultations, respectively, and the expert authority coefficients were all more than 0.85 at eachround. The final evaluation system included 4 first-level indicators and 15 second-level indicators. In the first-level indicators, “detecting effect” and “funds investment” had the mean weighted value of 4.53 and 4.49, which were relatively higher than that of“person-time investment“ and "operability“ (both 4.34). Among the second-level indicators under each first-level indicator, thefour most significant indicators included “ability of personnel in egg discrimination“, “cooperation of village cadres and doctors“,“Person-time on testing“ and “organizational start-up cost“, with the mean weighted values of 4.74, 4.43, 4.39 and 4.17, respectively. The coordination coefficients were 0.39 to 0.65, 0.28 to 0.58 and 0.45 to 0.65 at the first to the third round of the expertconsultations, respectively, and there were significant differences in the coordination coefficients at all three rounds of the consultations (all P < 0.05). Conclusions An evaluation system for the field assessment of the Kato-Katz technique in detecting soiltransmitted nematodes is successfully established, among which “ability of personnel in egg discrimination“ and “cooperation ofvillage cadres and doctors“ have the greatest mean weighted values of the significance.
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The current status of soil-transmitted nematodiasis in China is analyzed. The achievements in prevention and control of soil-transmitted nematodiasis are illustrated. Moreover, the challenges in condition of the decline of soil-transmitted nematodiasis in China are demonstrated. Finally, the working principals for prevention and control of soil-transmitted nematodiasis in the new period are proposed, combining with the health poverty alleviation project, focusing on the goals of control plan for important parasitic diseases, establishing monitoring system for soil-transmitted nematodiasis, and implementing the principles of precise prevention and control.
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Objective To understand the infection status of soil-transmitted nematodes in Xinchang County,so as to offer the evidence for the formulation of control measures.Methods The infection of soil-transmitted nematodes in residents was in-vestigated by using the Kato-Katz method and cellophane anal swab.Results A total of 3 069 people were examined in 2009,2012 and 2017,of which 1 520 people were male and 61 people were infected,with the infection rate of 4.01％;1 549 were women and 54 people were infected,with the infection rate of 3.48％.The infection rates of soil-transmitted nematodes in 2009,2012 and 2017 were 4.60％,4.29％and 2.35％,respectively,and the total infection rates were decreased(Χ2= 7.151,P＜0.05).Conclusion The rate of soil-transmitted nematode infection in Xinchang County is declining,and it is at a low epidemic level.
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Objective To understand the epidemic situation of soil-transmitted nematodiasis in the national surveillance site in Henan Province. Methods Over 1000 fecal samples from inhabitants in Huaiyang County of Henan Province,which was a national surveillance site,were collected each year from 2006 to 2015,the eggs of soil-transmitted nematodes and other intesti-nal helminths were examined by Kato-Kats technique. The cellophane swab method was used to detect Enterobius vermicularis eggs in children aged 3 to 12 years. In addition,the soil samples were collected from vegetable fields,lavatories,courtyards and kitchens of 10 families randomly selected in each year to examine Ascaris eggs by a modified saturated sodium nitrate floatation method. Results From 2006 to 2015,10419 persons were investigated,and the eggs of five species of intestinal helminths, Ascaris lumbricoides,Trichuris trichiura,hookworm,E. vermicularis,and Trichostrongylus orientalis,were detected,The aver-age infection rate of soil-transmitted nematodes in residents in Huaiyang County was 3.69%. The intensity of infection was mild and a family clustering was obvious. Both the infection rates of E. vermicularis in children and soil-transmitted nematodes in vil-lagers had no significant differences between different genders (both P>0.05). The infection rates of soil-transmitted nema-todes,A. lumbricoides and E. vermicularis all reached the highest in the age group of 1-10 years. For different education back-ground,the people with primary school education had the highest infection rate,and the infection rate showed a decreasing trend with the increase of the educational level. The infection rate of soil-transmitted nematodes in the national surveillance site in Henan Province showed a decreasing trend from 2006 to 2015. Unfertilized and fertilized A. lumbricoides eggs were detected in the soil samples,but the positive rate was very low. Conclusions In the recent 10 years,the infection rate of soil-transmit-ted nematodes in the national surveillance site in Henan Province shows a decreasing trend and maintains at a low level. The in-fection shows a family clustering. The children,especially those aged 3-9 years are the main infected population,and E. vermic-ularis infection is the key point of prevention and control.
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Objective To understand the status of soil-transmitted nematode infections,as well as the awareness and healthy behavior on soil-transmitted nematodiasis in rural residents of Dezhou City. Methods Six villages were selected according to the stratified sampling method;the permanent resident population aged 3 years or above was determined as the investigation objects. The modified Kato-Katz technique was adopted to detect the eggs of Ascaris lumbricoides,hookworm and Trichuris trichiura in the feces of the residents,and the method of cellophane anal swab was used to detect the Enterobius vermicularis infection in children under 12 years old. More than 50 households in each investigated site were randomly selected to investigate the awareness status on nematodiasis prevention and treatment and the condition of healthy behavior formation. Results A total of 2 294 residents were detected by Kato-Katz methods,11 of them were positive,and the total infection rate of soil-transmitted nematodes was 0.48%. To-tally 260 children were detected and 40 were infected with E. vermicularis,and the infection rate was 15.38%. A total of 898 resi-dents were investigated in the household survey and the awareness rate of nematodiasis prevention and treatment was 44.99%,the proportion of residents with healthy behavior was above 70%. Conclusions The infection rate of soil-transmitted nematode is low in rural areas of Dezhou City,but the infection rate of E. vermicularis in children is higher. The condition of healthy behavior forma-tion is satisfying,but the awareness rate of nematodiasis prevention and treatment of the residents is low. Therefore,the control measures as well as healthy education still should be strengthened.
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Objective To understand the status of Ascaris eggs pollution in soil at national monitoring spots of soil-transmit-ted nematodiasis,so as to provide the evidence for making countermeasures and evaluating the control effect. Methods Ten households were selected from each of the 22 national monitoring spots annually according to the National Surveillance Program of Soil-Transmitted Nematodiasis(Trial),and the soil samples from vegetable gardens,toilet periphery,courtyards and kitchens were collected and examined by using the modified floatation test with saturated sodium nitrate. Fertilized or unfertilized eggs as well as live or dead fertilized eggs were discriminated and identified. In addition,a SWOT analysis of monitoring of Ascaris eggs pollution in the soil of rural China was carried out. Results A total of 1 090 households were monitored in 22 monitoring spots from 2006 to 2010. The total detection rate of Ascaris eggs in the soil was 30.73%,and the detection rates of fertilized,unfertilized and live fertilized eggs were 13.21%,26.42%and 20.28%,respectively. The total detection rates of Ascaris eggs in the vegetable garden,toilet periphery,courtyard and kitchen were 16.51%,13.49%,14.22% and 10.73% respectively. The SWOT analysis demonstrated that the monitoring work had both advantages and disadvantages,and was faced with opportunities as well as threats. Conclusion The pollution status of Ascaris eggs in the soil is still quite severe at some national monitoring spots,and the counter-measures such as implementing hazard-free treatment of stool,improving water supply and sanitation and reforming environment should be taken to protect people from being infected.
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Objective To evaluate the effect of integrated control measures on soil-transmitted nematodiasis so as to provide the evidence for formulating the appropriate control strategies and measures in Jinhu County,Jiangsu Province. Methods Since 1995,the comprehensive control measures were carried out for soil-transmitted nematodiasis,and the measures included deworm-ing,health education,safe water,sanitation and environmental remediation. The effects of the comprehensive control measures were evaluated by the investigations of the prevalence of soil-transmitted nematodiasis,awareness of health knowledge,and behav-iors of residents. Results From 1995 to 2012,646 437 person-times were administrated in deworming medication with 2.48 times per capita;the benefit rate of safe water was 97.90%;the popularity rate of harmless toilets was 86.89%. The awareness rate of health knowledge increased from 54.05%in 1996 to 95.60%in 2012,the difference between them were statistically significant (χ2=230.92,P<0.01);the rate of correct health behaviors increased from 59.07%in 1996 to 96.40%in 2012,the difference between them had statistical significance(χ2=202.69,P<0.01). The prevalence of soil-transmitted nematodiasis decreased from 62.57%in 1989 to 1.21%in 2012,the difference had statistical significance(χ2=1 016.92,P<0.01). The infection rates of Asca-ris lumbricodes,hookworm and Trichuris trichiura were 0.58%,1.12%and 0,respectively in 2012,and compared with the rates of those infections in 1989,the decline rates were 94.96%,97.28%and 100%respectively,the differences between them were sta-tistically significant(χ2A sc aris =129.50,χ2hookworm=544.62,χ2Tri ch uris =254.19,all P<0.01). Conclusion The comprehensive control strategies and measures are effective and soil-transmitted nematodiasis has been controlled in Jinhu County.