Objective:To develop a quautitative PCR method for detecting hookworm infection and quantification.Methods:A real-time PCR method was designed hased on the intergenic regionⅡof ribosomal DNA of the hookworm Neeator a...Objective:To develop a quautitative PCR method for detecting hookworm infection and quantification.Methods:A real-time PCR method was designed hased on the intergenic regionⅡof ribosomal DNA of the hookworm Neeator americanus.The deteetion limit of this method was compared with the microscopy-hased Kato-Katz method.The real-time PCR method was used to conduct an epidemiological survey of hookworm infection in southern Fujian Province of China.Result:The real-time PCR method was specific for detecting Necator americanus infection,and was more sensitive than conventional PCR or microscopy-based method.A preliminary survey for hookworm infection in villages of Fujian Province confirmed the high prevalence of hnokworm infections in the resident populations.In addition,the infection rate in women was significantly higher than thai of in men.Conclusions:A real-time PCR method is designed,which has increased detection sensitivity for more accurate epidemiological studies of hookworm infections,especially when intensity of the infection needs to he considered.展开更多
Hookworm infection is a relatively common cause of anemia in endemic areas.The most common hookworm species are Ancylostoma duodenale and Necator americanus.In this report we present a case of overt gastrointestinal b...Hookworm infection is a relatively common cause of anemia in endemic areas.The most common hookworm species are Ancylostoma duodenale and Necator americanus.In this report we present a case of overt gastrointestinal bleeding Wause of hookworm infection.Capsule endoscopy revealed many hookworms in the lumen of proximal jejunum where active bleeding was seen. The patient was successfully treated with Albendazole.展开更多
A quantitative PCR（q PCR） assay was used to quantify Ancylostoma caninum ova in wastewater and sludge samples.We estimated the average gene copy numbers for a single ovum using a mixed population of ova.The average ...A quantitative PCR（q PCR） assay was used to quantify Ancylostoma caninum ova in wastewater and sludge samples.We estimated the average gene copy numbers for a single ovum using a mixed population of ova.The average gene copy numbers derived from the mixed population were used to estimate numbers of hookworm ova in A.caninum seeded and unseeded wastewater and sludge samples.The newly developed qP CR assay estimated an average of3.7 × 10~3 gene copies per ovum,which was then validated by seeding known numbers of hookworm ova into treated wastewater.The qP CR estimated an average of（1.1 ± 0.1）,（8.6 ± 2.9）and（67.3 ± 10.4） ova for treated wastewater that was seeded with（1 ± 0）,（10 ± 2） and（100 ± 21）ova,respectively.The further application of the q PCR assay for the quantification of A.caninum ova was determined by seeding a known numbers of ova into the wastewater matrices.The qP CR results indicated that 50%,90% and 67% of treated wastewater（1 L）,raw wastewater（1 L）and sludge（~4 g） samples had variable numbers of A.caninum gene copies.After conversion of the q PCR estimated gene copy numbers to ova for treated wastewater,raw wastewater,and sludge samples,had an average of 0.02,1.24 and 67 ova,respectively.The result of this study indicated that qP CR can be used for the quantification of hookworm ova from wastewater and sludge samples;however,caution is advised in interpreting qP CR generated data for health risk assessment.展开更多
Objective Our objective was to systematically evaluate chemotherapy-based control of ascariasis and hookworm infection and make predictions of the effectiveness of repeated mass treatment at different levels of covera...Objective Our objective was to systematically evaluate chemotherapy-based control of ascariasis and hookworm infection and make predictions of the effectiveness of repeated mass treatment at different levels of coverage in highly endemic areas of China. Methods Field surveys were carried out to acquire the ascariasis and hookworm prevalence and intensity （mean worm burden） at baseline, one month and one year later. We calculated model parameters based on the survey data, then incorporated them into a quantitative framework to predict the prevalence and intensity one year later. Sensitivity analyses were performed to assess the influence of the chemotherapy measures on prevalence and intensity, and model simulations were performed to evaluate the feasibility of achieving the proposed transmission control criteria under different chemotherapy measures. Results The predicted prevalence and intensity one year from baseline were within the 95% confidence interval of actual values. As treatment frequency or coverage increased, the prevalence and intensity decreased. Model simulations show that many rounds of treatment are needed to maintain the prevalence at a low level in highly endemic areas of China. Conclusion We should select different combinations of treatment frequency, coverage and drug efficacy according to available resources and practical attainable conditions. Mathematical modeling could be used to help optimize the chemotherapeutic scheme aiming at specific parasitic species and areas, and to direct the establishment of soil-transmitted helminthiasis control criteria in China.展开更多
基金supported by the Fujian Provincial Grants(2008N2005,2009-CXB-67)Xiamen City Science and Technology Grant(3502Z20094021)
文摘Objective:To develop a quautitative PCR method for detecting hookworm infection and quantification.Methods:A real-time PCR method was designed hased on the intergenic regionⅡof ribosomal DNA of the hookworm Neeator americanus.The deteetion limit of this method was compared with the microscopy-hased Kato-Katz method.The real-time PCR method was used to conduct an epidemiological survey of hookworm infection in southern Fujian Province of China.Result:The real-time PCR method was specific for detecting Necator americanus infection,and was more sensitive than conventional PCR or microscopy-based method.A preliminary survey for hookworm infection in villages of Fujian Province confirmed the high prevalence of hnokworm infections in the resident populations.In addition,the infection rate in women was significantly higher than thai of in men.Conclusions:A real-time PCR method is designed,which has increased detection sensitivity for more accurate epidemiological studies of hookworm infections,especially when intensity of the infection needs to he considered.
文摘Hookworm infection is a relatively common cause of anemia in endemic areas.The most common hookworm species are Ancylostoma duodenale and Necator americanus.In this report we present a case of overt gastrointestinal bleeding Wause of hookworm infection.Capsule endoscopy revealed many hookworms in the lumen of proximal jejunum where active bleeding was seen. The patient was successfully treated with Albendazole.
基金financial support from the Water Corporation(No.XX-09-13910)WA and the Commonwealth Scientific and Industry Research Organisation(CSIRO)(Grant No:EOP 77576),Land and Water Flagship
文摘A quantitative PCR（q PCR） assay was used to quantify Ancylostoma caninum ova in wastewater and sludge samples.We estimated the average gene copy numbers for a single ovum using a mixed population of ova.The average gene copy numbers derived from the mixed population were used to estimate numbers of hookworm ova in A.caninum seeded and unseeded wastewater and sludge samples.The newly developed qP CR assay estimated an average of3.7 × 10~3 gene copies per ovum,which was then validated by seeding known numbers of hookworm ova into treated wastewater.The qP CR estimated an average of（1.1 ± 0.1）,（8.6 ± 2.9）and（67.3 ± 10.4） ova for treated wastewater that was seeded with（1 ± 0）,（10 ± 2） and（100 ± 21）ova,respectively.The further application of the q PCR assay for the quantification of A.caninum ova was determined by seeding a known numbers of ova into the wastewater matrices.The qP CR results indicated that 50%,90% and 67% of treated wastewater（1 L）,raw wastewater（1 L）and sludge（~4 g） samples had variable numbers of A.caninum gene copies.After conversion of the q PCR estimated gene copy numbers to ova for treated wastewater,raw wastewater,and sludge samples,had an average of 0.02,1.24 and 67 ova,respectively.The result of this study indicated that qP CR can be used for the quantification of hookworm ova from wastewater and sludge samples;however,caution is advised in interpreting qP CR generated data for health risk assessment.
基金supported by the Special Fund for National Health Scientific Research in the Public Interest by the Ministry of Health of China (No.200802023)
文摘Objective Our objective was to systematically evaluate chemotherapy-based control of ascariasis and hookworm infection and make predictions of the effectiveness of repeated mass treatment at different levels of coverage in highly endemic areas of China. Methods Field surveys were carried out to acquire the ascariasis and hookworm prevalence and intensity （mean worm burden） at baseline, one month and one year later. We calculated model parameters based on the survey data, then incorporated them into a quantitative framework to predict the prevalence and intensity one year later. Sensitivity analyses were performed to assess the influence of the chemotherapy measures on prevalence and intensity, and model simulations were performed to evaluate the feasibility of achieving the proposed transmission control criteria under different chemotherapy measures. Results The predicted prevalence and intensity one year from baseline were within the 95% confidence interval of actual values. As treatment frequency or coverage increased, the prevalence and intensity decreased. Model simulations show that many rounds of treatment are needed to maintain the prevalence at a low level in highly endemic areas of China. Conclusion We should select different combinations of treatment frequency, coverage and drug efficacy according to available resources and practical attainable conditions. Mathematical modeling could be used to help optimize the chemotherapeutic scheme aiming at specific parasitic species and areas, and to direct the establishment of soil-transmitted helminthiasis control criteria in China.
