Prevalence of soil - borne nematode infections among residents living in urban/town areas of China in 2015 / 中国血吸虫病防治杂志

Objective To understand the prevalence of soil-borne nematode infections among residents living in urban/town areas of China, so as to provide insights into the control and elimination of soil-borne nematodiasis. Methods A total of 5 epidemic areas were classified in China according to the prevalence of human Clonorchis sinensis infections captured from the 2014–2015 national survey on major human parasitic diseases in China, and the total sample size was estimated according to the binomial distribution and Poisson’s distribution. Then, the total sample size was allocated proportionally to each province (autonomous region, municipality) of China based on the percentage of residents living in urban and town areas, and the number of survey sites in each province (autonomous region, municipality) was proportionally assigned according to the percentages of residents living in urban and town areas. Then, stratified sampling was performed at county, township and community levels according to the number of sampling sites in each province (autonomous region, municipality), and the survey site (community) was defined as the smallest sampling unit. All permanent residents in the survey sites were selected as the study subjects, and their stool samples were collected for identification and counting of parasite egg using a Kato-Katz technique. The prevalence and intensity of each parasite species were calculated. Results From 2014 to 2015, among the 133 231 residents detected in 31 provinces (autonomous regions, municipalities) of China, the overall prevalence of soil-borne nematode infections was 1.23% (1 636/133 231), and the prevalence rates of hookworm, Ascaris lumbricoides and Trichuris trichiura infections were 0.77% (1 032/133 231), 0.32% (426/133 231) and 0.17% (224/133 231), respectively. The highest prevalence of soil-borne nematode infections was seen in Jiangxi (4.03%, 82/2 034) and Chongqing (4.03%, 524/13 012), followed by in Hainan (3.47%, 72/2 075). The prevalence of soilborne nematode infections was 1.07% (662/62 139) in men and 1.37% (974/71 092) in women, and the greatest prevalence was found in residents at ages of 65 to 70 years (2.56%, 219/8 569). With regard to occupations and education levels, herdsmen (2.47%, 2/81) and illiterate residents (3.33%, 226/6 795) were found to have the highest prevalence of soil-borne nematode infections, respectively. In addition, mild infections were predominantly identified in hookworm-, A. lumbricoides- and T. trichiura-infected individuals (all > 90%). Conclusions The overall prevalence of soil-borne nematodiasis remains low in urban and town areas of China; however, human infections are widespread. According to the epidemiological features, health education combined with deworming are recommended to reduce the prevalence of soil-borne nematode infections among residents living in urban and town areas of China.

National surveillance on Enterobius vermicularis infections among children at ages of 3 to 9 years in China from 2016 to 2018 / 中国血吸虫病防治杂志

Objective To understand the epidemic status of Enterobius vermicularis infections among children aged 3 to 9 years in China, so as to provide scientific basis for the formulation of the prevention and control strategies for enterobiasis. Methods The national surveillance of enterobiasis was performed in 736 national surveillance sites (counties) from 30 provinces (municipalities/autonomous regions) in China from 2016 to 2018. All surveillance sites were classified into parts according to the geographical directions, including the eastern, western, southern, northern and middle parts, and a township was randomly selected from each part. Then, an administrative village was randomly selected from the township, and 200 permanent residents at ages of over 3 years living in the administrative village were randomly selected using the cluster sampling method. A total of 1 000 residents were examined in each surveillance site. E. vermicularis infections were detected among children at ages of 3 to 9 years using the modified Kato-Katz technique and the adhesive cellophane-tape perianal swab method, and the prevalence of infections was calculated and compared. Results The prevalence of E. vermicularis infections was 2.50%, 2.84% and 2.46% among children at ages of 3 to 9 years in the 736 surveillance sites from 30 provinces (municipalities/autonomous regions) in China from 2016 to 2018, and there was no gender-specific prevalence of E. vermicularis infections (P > 0.05). Enterobiasis was main prevalent in the southern and southwestern part of China (Jiangxi, Guangxi, Guangdong, Sichuan, Fujian, Chongqing and Hainan), with 5.00% prevalence and greater, and the highest prevalence was seen in Jiangxi and Guangxi for successive 3 years. In addition, the prevalence of E. vermicularis infections was higher in children with the Han ethnicity than in those with the minority ethnicity, and a high prevalence was found in children at ages of 4 to 7 years, and a low prevalence seen in children at ages of 3, 8 and 9 years. Conclusions The prevalences of E. vermicularis infections have not changed much among children at ages of 3 to 9 years in China from 2016 to 2018, and high prevalence is seen in southern and southwestern China, which should be given a high priority.

[Status and working principals of soil-transmitted nematodiasis during new period in China].

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.

Establishment of an evaluation system for the field assessment of the Kato-Katz technique in detection of soil-transmitted nematodiasis / 中国血吸虫病防治杂志

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.

Status and working principals of soil-transmitted nematodiasis during new period in China / 中国血吸虫病防治杂志

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.

[Epidemiological survey on clonorchiasis and awareness of prevention and control knowledge in Xinfeng County of Jiangxi Province].

OBJECTIVE: To understand the epidemic status of clonorchiasis and awareness of prevention and control knowledge in Xinfeng County of Jiangxi Province, so as to provide the evidences for control measures. METHODS: The baseline survey was carried out with a clue in vestigation of raw-fish eating behavior in potential endemic areas in 2016.The residents were examined by stool tests. The metacercariae of Clonorchis sinensis in fish, the rediae and cercariae in freshwater mollusk were detected. The feces samples of cats, dogs and pigs were collected and examined by sedimentation technique. Meanwhile, the epidemic factors, health knowledge and behavior were also surveyed. RESULTS: The residents in 26 villages had the habit of eating raw freshwater fish, and 19.51% of the respondents had this habit. The average infection rates of the population, Parafossarulus striatulus, freshwater fishes and reservoir hosts were 21.56%, 0, 8.24% and 2.27%, respectively. The infection rate of the population increased with age. There was a significant positive correlation between the behavior and the infection rate of the population (r = 0.88, P < 0.01). Only 11.46% of the respondents knew that eating raw-fish might cause C. sinensis infection, and 5.28% of them knew that C. sinensis was harmful to health. CONCLUSIONS: Twenty-six villages in five townships were endemic areas of clonorchiasis in Xinfeng County. The permanent solution of prevention and control of clonorchiasis is to strengthen the health education and change the habit of raw-fish eating gradually.

[Interpretation of Detection of Intestinal Helminthes-The Kato-Katz Method (WS/T 570-2017)].

The criteria for the Kato-Katz thick smear are compiled following the Management Measures for Health Criteria and GBT 1.1-2009 Standardization Working Guidelines. The criteria are composed of five chapters, including the range of application, terms and definitions, equipments, reagent materials, and testing procedures. Three informative appendices (identification of helminth eggs in human faeces, counting method of eggs in Kato-Katz thick smear, and other considerations) are appended. The criteria have been issued by the National Health and Family Planning Commission of the People's Republic of China, it provides a technical reference for the detection of helminth eggs in human faeces in medical institutions and disease prevention and control institutions.

[Establishing evaluation system for health education products of parasitic diseases by Delphi method].

OBJECTIVE: To establish an evaluation system for health education products of parasitic diseases by using a Delphi method, so as to provide references for the evaluation of health education products. METHODS: An expert panel was established and evaluation indicators were determined by brainstorming and face-to-face discussion, then the weight of each evaluation indicator was determined through a two-round Delphi method and the evaluation system was established. RESULTS: The evaluation indicators for material products, graphic design products and audio-visual products were established respectively by expert panel. Four first indicators and 12 second indicators were included in each type of products. The consensus was achieved following the two rounds of expert consultation among 23 knowledgeable and experienced experts, who considered "scientificity" and "acceptability" to be the most important of all the first indicators, and "information accuracy" and "behavioral guidance" of all the second indicators. CONCLUSIONS: A scientific and rational evaluation system is established, and it can be used in comprehensive evaluation of health education products for parasitic diseases.

Establishing evaluation system for health education products of parasitic dis-eases by Delphi method / 中国血吸虫病防治杂志

Objective To establish an evaluation system for health education products of parasitic diseases by using a Del-phi method,so as to provide references for the evaluation of health education products.Methods An expert panel was estab-lished and evaluation indicators were determined by brainstorming and face-to-face discussion,then the weight of each evalua-tion indicator was determined through a two-round Delphi method and the evaluation system was established.Results The eval-uation indicators for material products,graphic design products and audio-visual products were established respectively by ex-pert panel.Four first indicators and 12 second indicators were included in each type of products.The consensus was achieved fol-lowing the two rounds of expert consultation among 23 knowledgeable and experienced experts,who considered"scientificity"and"acceptability"to be the most important of all the first indicators,and"information accuracy"and"behavioral guidance"of all the second indicators.Conclusion A scientific and rational evaluation system is established,and it can be used in compre-hensive evaluation of health education products for parasitic diseases.

Interpretation of Detection of Intestinal Helminthes—The Kato-Katz Method (WS/T 570–2017) / 中国血吸虫病防治杂志

The criteria for the Kato-Katz thick smear are compiled following the Management Measures for Health Criteria and GBT 1.1–2009 Standardization Working Guidelines. The criteria are composed of five chapters, including the range of application, terms and definitions, equipments, reagent materials, and testing procedures. Three informative appendices (identification of helminth eggs in human faeces, counting method of eggs in Kato-Katz thick smear, and other considerations) are appended. The criteria have been issued by the National Health and Family Planning Commission of the People’s Republic of China, it provides a technical reference for the detection of helminth eggs in human faeces in medical institutions and disease prevention and control institutions.

Epidemiological survey on clonorchiasis and awareness of prevention and control knowledge in Xinfeng County of Jiangxi Province / 中国血吸虫病防治杂志

Objective To understand the epidemic status of clonorchiasis and awareness of prevention and control knowledge in Xinfeng County of Jiangxi Province, so as to provide the evidences for control measures. Methods The baseline survey was carried out with a clue in vestigation of raw-fish eating behavior in potential endemic areas in 2016.The residents were examined by stool tests. The metacercariae of Clonorchis sinensis in fish, the rediae and cercariae in freshwater mollusk were detected. The feces samples of cats, dogs and pigs were collected and examined by sedimentation technique. Meanwhile, the epidemic factors, health knowledge and behavior were also surveyed. Results The residents in 26 villages had the habit of eating raw freshwater fish, and 19.51% of the respondents had this habit. The average infection rates of the population, Parafossarulus striatulus, freshwater fishes and reservoir hosts were 21.56%, 0, 8.24% and 2.27%, respectively. The infection rate of the population increased with age. There was a significant positive correlation between the behavior and the infection rate of the population (r = 0.88, P < 0.01). Only 11.46% of the respondents knew that eating raw-fish might cause C. sinensis infection, and 5.28% of them knew that C. sinensis was harmful to health. Conclusions Twenty-six villages in five townships were endemic areas of clonorchiasis in Xinfeng County. The permanent solution of prevention and control of clonorchiasis is to strengthen the health education and change the habit of raw-fish eating gradually.

Interpretation of Detection of Intestinal Helminthes—The Kato-Katz Method (WS/T 570–2017) / 中国血吸虫病防治杂志

The criteria for the Kato-Katz thick smear are compiled following the Management Measures for Health Criteria and GBT 1.1–2009 Standardization Working Guidelines. The criteria are composed of five chapters, including the range of application, terms and definitions, equipments, reagent materials, and testing procedures. Three informative appendices (identification of helminth eggs in human faeces, counting method of eggs in Kato-Katz thick smear, and other considerations) are appended. The criteria have been issued by the National Health and Family Planning Commission of the People’s Republic of China, it provides a technical reference for the detection of helminth eggs in human faeces in medical institutions and disease prevention and control institutions.

Epidemiological survey on clonorchiasis and awareness of prevention and control knowledge in Xinfeng County of Jiangxi Province / 中国血吸虫病防治杂志

Objective To understand the epidemic status of clonorchiasis and awareness of prevention and control knowledge in Xinfeng County of Jiangxi Province, so as to provide the evidences for control measures. Methods The baseline survey was carried out with a clue in vestigation of raw-fish eating behavior in potential endemic areas in 2016.The residents were examined by stool tests. The metacercariae of Clonorchis sinensis in fish, the rediae and cercariae in freshwater mollusk were detected. The feces samples of cats, dogs and pigs were collected and examined by sedimentation technique. Meanwhile, the epidemic factors, health knowledge and behavior were also surveyed. Results The residents in 26 villages had the habit of eating raw freshwater fish, and 19.51% of the respondents had this habit. The average infection rates of the population, Parafossarulus striatulus, freshwater fishes and reservoir hosts were 21.56%, 0, 8.24% and 2.27%, respectively. The infection rate of the population increased with age. There was a significant positive correlation between the behavior and the infection rate of the population (r = 0.88, P < 0.01). Only 11.46% of the respondents knew that eating raw-fish might cause C. sinensis infection, and 5.28% of them knew that C. sinensis was harmful to health. Conclusions Twenty-six villages in five townships were endemic areas of clonorchiasis in Xinfeng County. The permanent solution of prevention and control of clonorchiasis is to strengthen the health education and change the habit of raw-fish eating gradually.

[Analysis of results of Assessment on National Parasitic Disease Control and Prevention Techniques in 2015].

OBJECTIVE: To assess the theoretical knowledge and practical skills of parasitic diseases among technicians from disease control and prevention institutions. METHODS: The Assessment on National Parasitic Disease Control and Prevention Techniques was organized in September, 2015. Together, 124 subjects from disease control and prevention institutions at province, prefecture or county levels in 31 provinces joined the assessment. A database was built consisting of subjects' basic information and assessment scores. Statistical analysis was used to analyze the scores by gender, age, professional title, institutions and places of participants. RESULTS: The average total score of all the subjects was 123.3, with a passing rate of 57.3%. The average scores of male subjects (48 subjects) and female subjects (76 subjects) were 125.9 and 121.7 respectively; the average scores of the subjects aged under 30 years (57 subjects), between 30 and 40 years (61 subjects) and above 40 years (6 subjects) were 119.6, 128.1 and 111.2 respectively; the average scores of persons with junior (94 subjects), intermediate (28 subjects) and senior (2 subjects) professional titles were 119.2, 135.9 and 140.5 respectively. The average theoretical assessment score of all the subjects was 61.9, with a passing rate of 62.9%. The average practical skill assessment score of all the subjects was 61.4, with a passing rate of 58.1%. CONCLUSIONS: The theoretical assessment results range widely. The theoretical knowledge results of technicians from disease control and prevention institutions are low in general. Therefore, the specific training based on daily work needs to be enhanced.

[Interpretation of Diagnostic Criteria for Clonorchiasis].

Clonorchis sinensis infection is carcinogenic to human, which results in cholangiocarcinoma, confirmed by the World Health Organization. An investigation in 2005 indicated that the standardized C. sinensis infection rate was 0.58%, with 12 490 000 infected people estimated in the clonorchiasis endemic areas in China. In the world, 80% of C. sinensis infected people were distributed in China. Diagnostic Criteria for Clonorchiasis (WS309-2009) was compiled by the ex-Ministry of Health of the People's Republic of China and it was issued and implemented in March 13, 2009. The Diagnostic Criteria for Clonorchiasis is composed of six chapters, including the Range of Application, Terms and Definitions, Diagnostic Basis, Diagnostic Principle, Diagnostic Standard, and Differential Diagnosis. Three informative appendices (etiology, epidemiology, clinical manifestation; enzyme-linked immunosorbent assay; differential diagnosis) and one normative appendix (laboratory examination) are appended. The Criteria provides the technical reference for diagnosis of clonorchiasis in medical institutions and disease control institutions. Combined with the current epidemic situation of clonorchiasis in China, this paper interprets the main contents of the Diagnostic Criteria for Clonorchiasis (WS309-2009), so as to promote its learning and implementing.

Twenty six cases of human Fasciola gigantica infection in Dali, Yunnan province / 中国地方病学杂志

Objective The aim of the study was to investigate the epidemic situation,clinical symptom,diagnosis and epidemiological characteristics of human Fasciola gigantica infection in Dali,Yunnan province.It will also provide a scientific basis for fasciolosis control and prevention.Methods Epidemic data were collected and patient's clinical signs and symptoms were studied.Serum soluble antigen of Fasciola gigantica of patients and part of family members and health people in the same village was detected using enzyme-linked immunosorbent assay (ELISA) and the eggs of Fasciola gigantica in stool were observed under microscope.Sequencing and PCR amplification of Fasciola gigantica eggs had been done.Sequencing results were analyzed using basic local alignment search tool (BLAST) program of the U.S.National Center for Biotechnology Information (NCBI) and the similarity of the two in the sequence of nucleic acid was compared.Furthermore,patients were experimentally given orally therapeutic doses of Triclabendazole 10 mg·kg-1·d-1 daily for 2 days,and kept in the hospital for observation for one week.Moreover,host and vector were investigated in the surrounding ditches of Dali prefecture and Limnaea peregra snail samples were collected.All the snails were squashed by glass sheet in order to detect the cercarie.Cow dung and sheep manure was collected in the Limnaea peregra distribution environment,and the eggs in the feces were checked by microscope after washing and precipitation.Results All the 26 patients had a continued hyperpyrexia with distinct alimentary system symptoms of nausea,vomiting,stomachache,abdominal distension as well as hepatomegaly,sensitive to percussion,different levels of liver damage detected by CT.All the patients had an eaten history of raw Herba Houttuyniae and other aquatic plants,and the course of the disease was similar,with the same epidemiological characteristics.ELISA detection was used in the 26 patients,family members and other healthy population,the results of all the 26 patients were positive(100.0％,26/26) ; the positive rates of the 57 family members and other health people of the same village were 31.6％ (18/57) and 17.1％ (6/35),respectively.The results of sequencing and BLAST program showed that the pathogen was Fasciola gigantica with the similarity between 99％-100％.PCR amplification also confirmed that the eggs were Fasciola gigantica eggs with an approximately 1000 bp band on agarose gel.After treatment with Triclabendazole,body temperature of the patients dropped to normal and symptoms improved markedly.Moreover,329 Limnaea peregra snails were collected including 5 ones with redia and one-tailed cercariae which were preliminary identified as the larva of Fasciola gigantica.There were also eggs of Fasciola gigantica detected in one stool of cattle and one of goat.Conclusions Eating raw food is the leading cause of the onset of the disease.Triclabendazole is the drug of choice to treat Fasciolasis.Health education should be strengthened by government and disease prevention and control departments in order to make the local residents to understand the potential hazard of eating raw aquatic vegetable and drinking unboiled water,which is the key to prevent the occurrence of the disease.

[Prevention and treatment of ascariasis in demonstration plots of integrated control from 2006 to 2009].

OBJECTIVE: To understand the situation of Ascaris lumbricoides infection in the demonstration plots and evaluate the effect of integrated intervention measures. METHODS: The integrated intervention measures included health education, mass chemotherapy, safe water and sanitary toilets. The changes of infection rates of Ascaris lumbricoides in residents were observed before and after the intervention. RESULTS: With the 3-year's intervention, the Ascaris lumbricoides infection rates decreased from 17.81% to 2.52%, the rate of mass chemotherapy was 81.65%, which covered more than 6.2 million person-time, the awareness rates of parasitic disease control knowledge among the residents raised from 45.11% to 95.99%, and 84.09% of local people were supplied with safe water and 50.30% of families had sanitary toilets. CONCLUSION: The Ascaris lumbricoides infection rate decreases dramatically through the 3-year's intervention.

[Analysis of influencing factors of Trichuris trichiura infection in demonstration plots of comprehensive control of parasitic diseases].

OBJECTIVE: To understand the main risk factors of Trichuris trichiura infection in plots carrying out the integrated control of parasitic diseases. METHODS: The simple and multiple unconditional logistic regression were applied to analyze related data from the database of baseline survey in demonstration plots carrying out the integrated control of parasitic diseases. RESULTS: The results of simple logistic regression analysis suggested that the effects of 7 factors to Trichuris trichiura infection were significant (all P values were less than 0.05), namely drinking water resources, toilet type, fertilization type of farmland, fertilization type of vegetable field, washing hands after defecation, eating raw vegetables, melons and fruits and taking anthelminthic before examination. Among the factors above, eating raw vegetables, melons and fruits was of high risk (OR = 2.302), washing hands after defecation and taking anthelminthic before examination were two protection factors (with OR of 0.904 and 0.664, respectively). Compared to feces of human and livestock, fertilizing chemical fertilizer and compound fertilizer in farmland and vegetable field showed more obvious protection effect (with OR of 0.864 and 0.854, respectively). Drinking well water and spring water were two protection factors (with OR of 0.843 and 0.567, respectively). Simple toilet indoor and biogas pool also showed protection effect (with OR of 0.576 and 0.687, respectively). Multivariate analysis showed that four factors including eating raw vegetables, melons and fruits, fertilization type of farmland, fertilization type of vegetable field and taking anthelminthic before examination were determined to be the main influencing factors of Trichuris trichiura infection. CONCLUSIONS: The main influencing factors of Trichuris trichiura infection in demonstration plots for the integrated control of parasitic diseases include eating raw vegetables, melons and fruits and fertilization type of farmland and vegetable field. Besides those, taking anthelminthic could reduce Trichuris trichiura infection of the population, meanwhile, sanitary water supply and latrine improvement could also reduce the risk of infection.