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Zhao S, Zhang Q, Wang X, Li W, Juma S, Berquist R, Zhang J, Yang K. Development and performance of recombinase-aided amplification (RAA) assay for detecting Schistosoma haematobium DNA in urine samples. Heliyon 2023; 9:e23031. [PMID: 38144328 PMCID: PMC10746445 DOI: 10.1016/j.heliyon.2023.e23031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 11/17/2023] [Accepted: 11/24/2023] [Indexed: 12/26/2023] Open
Abstract
Rapid diagnosis of urogenital schistosomiasis caused by Schistosoma haematobium requires an accurate and timely assay, especially for low-intensity S. haematobium infection cases and in non-endemic areas. The mitochondrial cytochrome c oxidase 1 (cox1) gene fragment of S. haematobium was selected as detection target as this short fragment, which can be rapidly sequenced and yet possess good diagnostic resolution. A pair of primers and a fluorescent probe were designed according to the principle of recombinase-aided amplification (RAA), which was subsequently optimized and applied as an S. haematobium-specific RAA assay. Its diagnostic performance was validated for sensitivity and specificity in comparison to microscopy-based egg counting after urine filtration. The RAA assay could detect as little as 10 copies/μL of S. haematobium recombinant plasmid, and no cross-reactions were observed with S. mansoni, S. japonicum, Ancylostoma duodenale, Clonorchis sinensis, Echinococcus granulosus, or Ascaris lumbricoides. This test can be conducted at 39 °C and the whole RAA reaction can be completed within 20 min. The validation of the RAA assay showed that it had 100 % consistency with urine-egg microscopy, as it does not require an elaborate reading tool, is simple to use, and should be useful for field diagnostics and point-of-care applications.
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Affiliation(s)
- Song Zhao
- Jiangsu Institute of Parasitic Diseases, Key Laboratory on Technology for Parasitic Disease Prevention and Control, Ministry of Health, Jiangsu Provincial Key Laboratory on the Molecular Biology of Parasites, Wuxi, Jiangsu, China
- Jiangnan University, Wuxi, Jiangsu, China
| | - Qiaoqiao Zhang
- Jiangsu Institute of Parasitic Diseases, Key Laboratory on Technology for Parasitic Disease Prevention and Control, Ministry of Health, Jiangsu Provincial Key Laboratory on the Molecular Biology of Parasites, Wuxi, Jiangsu, China
- Department of Clinical Laboratory, The 904th Hospital of Joint Logistic Support Force of PLA, Wuxi, Jiangsu, 214044, China
| | - Xinyao Wang
- Jiangsu Institute of Parasitic Diseases, Key Laboratory on Technology for Parasitic Disease Prevention and Control, Ministry of Health, Jiangsu Provincial Key Laboratory on the Molecular Biology of Parasites, Wuxi, Jiangsu, China
| | - Wei Li
- Jiangsu Institute of Parasitic Diseases, Key Laboratory on Technology for Parasitic Disease Prevention and Control, Ministry of Health, Jiangsu Provincial Key Laboratory on the Molecular Biology of Parasites, Wuxi, Jiangsu, China
| | - Saleh Juma
- Ministry of Health of Zanzibar, P.O. Box 236, Zanzibar, United Republic of Tanzania
| | - Robert Berquist
- Ingerod, Brastad, Sweden (formerly with the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Jianfeng Zhang
- Jiangsu Institute of Parasitic Diseases, Key Laboratory on Technology for Parasitic Disease Prevention and Control, Ministry of Health, Jiangsu Provincial Key Laboratory on the Molecular Biology of Parasites, Wuxi, Jiangsu, China
| | - Kun Yang
- Jiangsu Institute of Parasitic Diseases, Key Laboratory on Technology for Parasitic Disease Prevention and Control, Ministry of Health, Jiangsu Provincial Key Laboratory on the Molecular Biology of Parasites, Wuxi, Jiangsu, China
- Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, 211166, China
- Jiangnan University, Wuxi, Jiangsu, China
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Tong Y, Tang L, Xia M, Li G, Hu B, Huang J, Wang J, Jiang H, Yin J, Xu N, Chen Y, Jiang Q, Zhou J, Zhou Y. Identifying determinants for the seropositive rate of schistosomiasis in Hunan province, China: A multi-scale geographically weighted regression model. PLoS Negl Trop Dis 2023; 17:e0011466. [PMID: 37440524 DOI: 10.1371/journal.pntd.0011466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 06/16/2023] [Indexed: 07/15/2023] Open
Abstract
BACKGROUND Schistosomiasis is of great public health concern with a wide distribution and multiple determinants. Due to the advances in schistosomiasis elimination and the need for precision prevention and control, identifying determinants at a fine scale is urgent and necessary, especially for resource deployment in practice. Our study aimed to identify the determinants for the seropositive rate of schistosomiasis at the village level and to explore their spatial variations in local space. METHODOLOGY The seropositive rates of schistosomiasis were collected from 1714 villages or communities in Human Province, and six spatial regression models including ordinary least squares (OLS), spatial lag model (SLM), spatial error model (SEM), geographically weighted regression (GWR), robust GWR (RGWR) and multiscale GWR (MGWR) were used to fit the data. PRINCIPAL/FINDINGS MGWR was the best-fitting model (R2: 0.821, AICc:2727.092). Overall, the nearest distance from the river had the highest mean negative correlation, followed by proportion of households using well water and the annual average daytime surface temperature. The proportions of unmodified toilets showed the highest mean positive correlation, followed by the snail infested area, and the number of cattle. In spatial variability, the regression coefficients for the nearest distance from the river, annual average daytime surface temperature and the proportion of unmodified toilets were significant in all villages or communities and varied little in local space. The other significant determinants differed substantially in local space and had significance ratios ranging from 41% to 70%, including the number of cattle, the snail infested area and the proportion of households using well water. CONCLUSIONS/SIGNIFICANCE Our study shows that MGWR was well performed for the spatial variability of schistosomiasis in Hunan province. The spatial variability was different for different determinants. The findings for the determinants for the seropositive rate and mapped variability for some key determinants at the village level can be used for developing precision intervention measure for schistosomiasis control.
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Affiliation(s)
- Yixin Tong
- Fudan University School of Public Health, Shanghai, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Shanghai, China
- Fudan University Center for Tropical Disease Research, Shanghai, China
| | - Ling Tang
- Hunan Institute for Schistosomiasis Control, Yueyang, China
| | - Meng Xia
- Hunan Institute for Schistosomiasis Control, Yueyang, China
| | - Guangping Li
- Hunan Institute for Schistosomiasis Control, Yueyang, China
| | - Benjiao Hu
- Hunan Institute for Schistosomiasis Control, Yueyang, China
| | - Junhui Huang
- Fudan University School of Public Health, Shanghai, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Shanghai, China
- Fudan University Center for Tropical Disease Research, Shanghai, China
| | - Jiamin Wang
- Fudan University School of Public Health, Shanghai, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Shanghai, China
- Fudan University Center for Tropical Disease Research, Shanghai, China
| | - Honglin Jiang
- Fudan University School of Public Health, Shanghai, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Shanghai, China
- Fudan University Center for Tropical Disease Research, Shanghai, China
| | - Jiangfan Yin
- Fudan University School of Public Health, Shanghai, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Shanghai, China
- Fudan University Center for Tropical Disease Research, Shanghai, China
| | - Ning Xu
- Fudan University School of Public Health, Shanghai, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Shanghai, China
- Fudan University Center for Tropical Disease Research, Shanghai, China
| | - Yue Chen
- School of Epidemiology and Public Health, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Qingwu Jiang
- Fudan University School of Public Health, Shanghai, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Shanghai, China
- Fudan University Center for Tropical Disease Research, Shanghai, China
| | - Jie Zhou
- Hunan Institute for Schistosomiasis Control, Yueyang, China
| | - Yibiao Zhou
- Fudan University School of Public Health, Shanghai, China
- Key Laboratory of Public Health Safety, Fudan University, Ministry of Education, Shanghai, China
- Fudan University Center for Tropical Disease Research, Shanghai, China
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de Araújo AD, Carvalho ODS, Gava SG, Caldeira RL. DNA barcoding as a valuable tool for delimiting mollusk species of the genus Biomphalaria Preston, 1910 (Gastropoda: Planorbidae). Front Cell Infect Microbiol 2023; 13:1167787. [PMID: 37168391 PMCID: PMC10165093 DOI: 10.3389/fcimb.2023.1167787] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 03/22/2023] [Indexed: 05/13/2023] Open
Abstract
Introduction The genus Biomphalaria in Brazil includes 11 species and one subspecies, three of which are intermediate hosts of Schistosoma mansoni. Due to the recent evolution of this group, some species are difficult to identify based on morphological characters, making the use of genetic markers necessary for species identification. This study aimed to evaluate the use of partial sequences of the cytochrome c oxidase I (coi) gene for the identification of Biomphalaria species using phylogenetic reconstruction and species delimitation algorithms. The study tested the use of DNA barcoding technique for species delimitation within the genus. Methods DNA barcoding was performed by sequencing a partial region of the coi gene from specimens, and the sequences were analyzed using phylogenetic reconstruction and algorithms to delimit Operational Taxonomic Units (OTUs). Results The study found that the use of the coi gene in the reconstruction of the phylogeny of the genus might be an alternative for understanding the evolution and dispersion of species. However, this marker alone is not enough to solve complex taxonomic problems within the genus. A total of 223 sequences were analyzed, 102 of which could be separated using the barcode gap, enabling the correct identification of seven taxa. Discussion The study demonstrated that accurate mollusk identification is necessary for effective schistosomiasis control. The DNA barcoding methodology was found to be promising for accurate mollusk identification, which is crucial for concentrating schistosomiasis control efforts in places where it is needed.
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Wang X, Juma S, Li W, Suleman M, Muhsin MA, He J, He M, Xu D, Zhang J, Bergquist R, Yang K. Potential risk of colonization of Bulinus globosus in the mainland of China under climate change. Infect Dis Poverty 2022; 11:52. [PMID: 35562755 PMCID: PMC9103089 DOI: 10.1186/s40249-022-00980-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 04/25/2022] [Indexed: 11/17/2022] Open
Abstract
Background Bulinus globosus, the main intermediate snail host of Schistosoma haematobium. The increased contacts between Africa and China could even lead to large-scale dissemination of B. globosus in China. Temperature is the key factor affecting fresh-water snail transmission. This study predicted potential risk of colonization of B. globosus in the mainland of China under climate change. Methods We investigated minimum and maximum temperatures for B. globosus eggs, juveniles and adult snails kept under laboratory conditions to find the most suitable range by pinpointing the median effective temperatures (ET50). We also assessed the influence of temperature on spawning and estimated the accumulated temperature (AT). The average air temperatures between 1955 and 2019 in January and July, the coldest and hottest months in China, respectively, were collected from national meteorological monitoring stations and investigated in a geographic information system (GIS) using empirical Bayesian Kriging to evaluate the theoretical possibility for distribution of B. globosus in southern China based on temperature. Results The effective minimum temperature (ET50min) for eggs, juveniles, adult snails and spawning were 8.5, 7.0, 7.0, 14.9 °C, respectively, with the corresponding maximum values (ET50max) of 36.6, 40.5, 40.2 and 38.1 °C. The AT was calculated at 712.1 ± 64.9 °C·d. In 1955, the potential B. globosus distribution would have had a northern boundary stretching from the coastal areas of Guangdong Province and Guangxi Autonomous Region to southern Yunnan Province. Since then, this line has gradually moved northward. Conclusions Annual regeneration of B. globosus can be supported by the current climate conditions in the mainland of China, and a gradual expansion trend from south to north is shown in the study from 2015 to 2019. Thus, there is a potential risk of colonization of B. globosus in the mainland of China under climate change. Graphical Abstract ![]()
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Affiliation(s)
- Xinyao Wang
- Jiangsu Institute of Parasitic Diseases, Wuxi, 214064, Jiangsu, China.,Key Laboratory On Technology for Parasitic Disease Prevention and Control, Jiangsu Provincial Key Laboratory On the Molecular Biology of Parasites, Ministry of Health, Wuxi, 214064, Jiangsu, China
| | - Saleh Juma
- Ministry of Health of Zanzibar, P.O. Box 236, Zanzibar, United Republic of Tanzania
| | - Wei Li
- Jiangsu Institute of Parasitic Diseases, Wuxi, 214064, Jiangsu, China.,Key Laboratory On Technology for Parasitic Disease Prevention and Control, Jiangsu Provincial Key Laboratory On the Molecular Biology of Parasites, Ministry of Health, Wuxi, 214064, Jiangsu, China
| | - Mchanga Suleman
- Ministry of Health of Zanzibar, P.O. Box 236, Zanzibar, United Republic of Tanzania
| | - Mtumweni Ali Muhsin
- Ministry of Health of Zanzibar, P.O. Box 236, Zanzibar, United Republic of Tanzania.,College of Medicine, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Jian He
- Jiangsu Institute of Parasitic Diseases, Wuxi, 214064, Jiangsu, China.,Key Laboratory On Technology for Parasitic Disease Prevention and Control, Jiangsu Provincial Key Laboratory On the Molecular Biology of Parasites, Ministry of Health, Wuxi, 214064, Jiangsu, China
| | - Mingzhen He
- Changzhou Center for Disease Control and Prevention, Changzhou, Jiangsu, China
| | - Dacheng Xu
- Jintan Center for Disease Control and Prevention, Changzhou, Jiangsu, China
| | - Jianfeng Zhang
- Jiangsu Institute of Parasitic Diseases, Wuxi, 214064, Jiangsu, China.,Key Laboratory On Technology for Parasitic Disease Prevention and Control, Jiangsu Provincial Key Laboratory On the Molecular Biology of Parasites, Ministry of Health, Wuxi, 214064, Jiangsu, China
| | | | - Kun Yang
- Jiangsu Institute of Parasitic Diseases, Wuxi, 214064, Jiangsu, China. .,Key Laboratory On Technology for Parasitic Disease Prevention and Control, Jiangsu Provincial Key Laboratory On the Molecular Biology of Parasites, Ministry of Health, Wuxi, 214064, Jiangsu, China. .,College of Medicine, Jiangnan University, Wuxi, 214122, Jiangsu, China. .,School of Public Health, Nanjing Medical University, Nanjing, China.
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Schistosoma japonicum translationally controlled tumor protein, which is associated with the development of female worms, as a target for control of schistosomiasis. Int J Parasitol 2022; 52:569-579. [DOI: 10.1016/j.ijpara.2022.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 12/14/2022]
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Buchwald AG, Grover E, Van Dyke J, Kechris K, Lu D, Liu Y, Zhong B, Carlton EJ. Human Mobility Associated With Risk of Schistosoma japonicum Infection in Sichuan, China. Am J Epidemiol 2021; 190:1243-1252. [PMID: 33438003 DOI: 10.1093/aje/kwaa292] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 12/15/2020] [Accepted: 12/29/2020] [Indexed: 11/12/2022] Open
Abstract
Urbanization increases human mobility in ways that can alter the transmission of classically rural, vector-borne diseases like schistosomiasis. The impact of human mobility on individual-level Schistosoma risk is poorly characterized. Travel outside endemic areas may protect against infection by reducing exposure opportunities, whereas travel to other endemic regions may increase risk. Using detailed monthly travel- and water-contact surveys from 27 rural communities in Sichuan, China, in 2008, we aimed to describe human mobility and to identify mobility-related predictors of S. japonicum infection. Candidate predictors included timing, frequency, distance, duration, and purpose of recent travel as well as water-contact measures. Random forests machine learning was used to detect key predictors of individual infection status. Logistic regression was used to assess the strength and direction of associations. Key mobility-related predictors include frequent travel and travel during July-both associated with decreased probability of infection and less time engaged in risky water-contact behavior, suggesting travel may remove opportunities for schistosome exposure. The importance of July travel and July water contact suggests a high-risk window for cercarial exposure. The frequency and timing of human movement out of endemic areas should be considered when assessing potential drivers of rural infectious diseases.
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Xiong YH, Xu XN, Zheng B. Patented technologies for schistosomiasis control and prevention filed by Chinese applicants. Infect Dis Poverty 2021; 10:84. [PMID: 34118989 PMCID: PMC8199835 DOI: 10.1186/s40249-021-00869-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 05/25/2021] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Many valuable and productive patented technologies have been developed to control schistosomiasis in China in the past 70 years. We conducted a research to analyse patented technologies for schistosomiasis control and prevention filed by Chinese applicants for determining the future patent layout. METHODS The patent databases of China National Intellectual Property Administration and Baiten were comprehensively searched, and patented technologies for schistosomiasis control and prevention, published between January 1950 and December 2020 filed by Chinese applicants were sorted on 30 December 2020. The patent types, technical fields, and patent development trends were analysed using patent indexing. RESULTS There are 184 valid schistosomiasis control technology patents, among them 128 invention patents. The patents related to schistosomiasis control and prevention technology have gone through the germination, growth, and maturity stages. These phases correspond with three phases in schistosomiasis control in China. The main technical aspects were fundamental research (n = 37), detection (n = 13), chemotherapy (n = 61), and armamentarium/devices (n = 73), of which the number of patents for detection for diagnosis was smaller. The top three specialised technical fields for patents subgroups, focusing on antiparasitic agents, DNA or RNA, vectors and medicines, of which schistosomicides are the major dominant subgroup. CONCLUSIONS We recommend that technologies to be patented for schistosomiasis control and prevention be focused on detection, preliminary studies for molecular detection methods should be significantly enhanced, and patent layout must be performed, which will, in turn, promote accuracy of early diagnosis, not only in humans but also in livestock. It is necessary to develop more anti-schistosomal drugs safely and effectively, exceptionally eco-friendly molluscicides and herbal extracts anti-schistosomes, improve treatment, develop vaccines for use in humans.
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Affiliation(s)
- Yan-Hong Xiong
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Chinese Center for Tropical Diseases Research, Key Laboratory of Parasite and Vector Biology, National Health Commission, WHO Centre for Tropical Diseases, National Center for International Research On Tropical Diseases, Ministry of Science and Technology, Shanghai, 200025, China
| | - Xue-Nian Xu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Chinese Center for Tropical Diseases Research, Key Laboratory of Parasite and Vector Biology, National Health Commission, WHO Centre for Tropical Diseases, National Center for International Research On Tropical Diseases, Ministry of Science and Technology, Shanghai, 200025, China
| | - Bin Zheng
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Chinese Center for Tropical Diseases Research, Key Laboratory of Parasite and Vector Biology, National Health Commission, WHO Centre for Tropical Diseases, National Center for International Research On Tropical Diseases, Ministry of Science and Technology, Shanghai, 200025, China.
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Habib MR, Lv S, Rollinson D, Zhou XN. Invasion and Dispersal of Biomphalaria Species: Increased Vigilance Needed to Prevent the Introduction and Spread of Schistosomiasis. Front Med (Lausanne) 2021; 8:614797. [PMID: 33644096 PMCID: PMC7902764 DOI: 10.3389/fmed.2021.614797] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 01/06/2021] [Indexed: 11/13/2022] Open
Abstract
Biological invasion is a matter of great concern from both public health and biodiversity perspectives. Some invasive snail species may trigger disease emergence by acting as intermediate hosts. The geographic distribution of Schistosoma mansoni depends on the presence of susceptible species of Biomphalaria freshwater snails that support the parasite's transformation into infective stages. Biomphalaria spp. have shown strong local and global dispersal capacities that may increase due to the global warming phenomenon and increases in the development of agricultural and water projects. Should intermediate hosts become established in new areas then this will create potential transmission foci. Examples of snail invasions that have had an impact on schistosomiasis transmission include the introduction of Biomphalaria tenagophila to Congo and B. glabrata to Egypt. The current spread of B. straminea in China is causing concern and needs to be monitored closely. An understanding of the mode of invasion and distribution of these snails as well as their experimental susceptibility to S. mansoni will predict the potential spread of schistosomiasis. Here we review the invasion patterns of Biomphalaria snails and factors that control their distribution and the impact that invasion may have on intestinal schistosomiasis transmission. In addition, we propose some possible surveillance responses for optimum control strategies and interventions. Whenever possible, swift action should be taken to contain any new occurrence of these intermediate snail hosts.
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Affiliation(s)
- Mohamed R. Habib
- Medical Malacology Laboratory, Theodor Bilharz Research Institute, Giza, Egypt
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention, Shanghai, China
- Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, China
| | - Shan Lv
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention, Shanghai, China
- Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, China
- National Center for International Research on Tropical Diseases, Shanghai, China
- WHO Collaborating Center on Tropical Diseases, Shanghai, China
- School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - David Rollinson
- Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention, Shanghai, China
- Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, China
- National Center for International Research on Tropical Diseases, Shanghai, China
- WHO Collaborating Center on Tropical Diseases, Shanghai, China
- School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Lin D, Zeng X, Sanogo B, He P, Xiang S, Du S, Zhang Y, Wang L, Wan S, Zeng X, Yang Y, Lv Z, Liang Y, Deng Z, Hui JHL, Yuan D, Ding T, Wu Z, Sun X. The potential risk of Schistosoma mansoni transmission by the invasive freshwater snail Biomphalaria straminea in South China. PLoS Negl Trop Dis 2020; 14:e0008310. [PMID: 32511225 PMCID: PMC7302743 DOI: 10.1371/journal.pntd.0008310] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 06/18/2020] [Accepted: 04/20/2020] [Indexed: 01/09/2023] Open
Abstract
Schistosomes infect more than 200 million people worldwide, and globally, over 700 million people are at risk of infection. The snail Biomphalaria straminea, as one of the intermediate hosts of Schistosoma mansoni, consecutively invaded Hong Kong in 1973, raising great concern in China. In this study, a malacological survey was conducted over a period of four years, and investigations were performed on the mechanism of susceptibility of B. straminea to S. mansoni. B. straminea was investigated in China from 2014 to 2018. Out of 185 investigated sites, 61 were positive for stages of black B. straminea (BBS), which shows pigmented spots. Twenty of the 61 sites were positive for red B. straminea (RBS), which is partially albino and red colored. Phylogenetic analyses based on cox1 and 18S rRNA sequences demonstrated that both phenotypes were clustered with Brazilian strains. No S. mansoni infections were detected in field-collected snail. However, in laboratory experiments, 4.17% of RBS were susceptible to a Puerto Rican strain of S. mansoni, while BBS was not susceptible. The highest susceptibility rate (70.83%) was observed in the F2 generation of RBS in lab. The density of RBS has increased from south to north and from west to east in Guangdong since 2014. Five tyrosinase tyrosine metabolism genes were upregulated in BBS. Transcriptome comparisons of RBS and BBS showed that ficolin, C1q, MASP-like, and membrane attack complex (MAC)/perforin models of the complement system were significantly upregulated in BBS. Our study demonstrated that B. straminea is widely distributed in Hong Kong and Guangdong Province, which is expanding northwards very rapidly as a consequence of its adaptation to local environments. Our results suggest that B. straminea from South China is susceptible to S. mansoni, implying the high potential for S. mansoni transmission and increased S. mansoni infection risk in China. Biomphalaria straminea is an important intermediate host for the blood fluke Schistosoma mansoni. B. straminea has spread in Hong Kong and in mainland China since 1973. However, whether resident snails can transmit intestinal schistosomiasis caused by S. mansoni remains unclear. Our results revealed that different types of B. straminea are widespread in cities such as Hong Kong, Shenzhen, Dongguan, Huizhou and Puning and that the distribution of the species has shifted northwards. The most important finding was that one of the phenotypes (red phenotype of B. straminea, RBS), which is highly susceptible to S. mansoni, has spread into the city of Shenzhen since 2016. The density of RBS in Guangdong Province has increased rapidly since 2014, especially since 2016. Transcriptome analysis showed that the high expression levels of ficolin, C1q, MASP-like, and membrane attack complex (MAC)/perforin models of the complement system might be associated with the mechanism of susceptibility. Our study suggested that B. straminea is susceptible to S. mansoni, implying a high potential risk of S. mansoni transmission in South China. More attention should be paid to the potential transmission of S. mansoni, and control measures should be established to prevent the spread of this snail in South China.
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Affiliation(s)
- DaTao Lin
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - Xin Zeng
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - Benjamin Sanogo
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - Ping He
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - Suoyu Xiang
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - Shuling Du
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - YanHua Zhang
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - Lifu Wang
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - Shuo Wan
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - XingDa Zeng
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - Ya Yang
- Key Laboratory of Public Health Safety, Ministry of Education, Tropical Disease Research Center, Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
| | - ZhiYue Lv
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - YouSheng Liang
- Jiangsu Institute of Parasitic Diseases, Wuxi, Jiansu Province, China
| | - ZhuoHui Deng
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, Guangdong Province, China
| | - Jerome Ho-Lam Hui
- State Key Laboratory of Agrobiotechnology, School of Life Science, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China
| | - DongJuan Yuan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Tao Ding
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
| | - ZhongDao Wu
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
- * E-mail: (ZDW); (XS)
| | - Xi Sun
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Provincial Engineering Technology Research Center for Diseases-vectors Control, Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, Guangdong, China
- * E-mail: (ZDW); (XS)
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10
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Zhang LJ, Mwanakasale V, Xu J, Sun LP, Yin XM, Zhang JF, Hu MC, Si WM, Zhou XN. Diagnostic performance of two specific schistosoma japonicum immunological tests for screening schistosoma haematobium in school children in Zambia. Acta Trop 2020; 202:105285. [PMID: 31786108 DOI: 10.1016/j.actatropica.2019.105285] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 11/22/2019] [Accepted: 11/27/2019] [Indexed: 12/27/2022]
Abstract
Dipstick Dye Immunoassay (DDIA) and Indirect Haemagglutination Assay (IHA), are two commercially available kits which have been widely used for screening Schistosoma japonicum in P.R. China. Whether they can be used for screening of Schistosoma haematobium are not clear. In order to evaluate the diagnostic efficiency of DDIA and IHA for screening Schistosoma haematobium, serum samples were collected from pupils in endemic areas in Zambia, Southern Africa, and tested by DDIA and IHA by single-blind manner. Meanwhile, the pupils were microscopically examined by infection with Schistosoma and soil-transmitted helminths, visually observed for parasite eggs. Of the enrolled 148 pupils, 61% tested positive for S. haematobium infection, while 31% and 36% of pupils were infected with hookworm and Ascaris respectively. Regarding the parasitological tests as reference standard, for the diagnosis of S. haematobium infection, IHA performed higher sensitivity (74%, 95% CI: 65%-83%) than that of DDIA (60%, 95%CI: 49%-70%). The sensitivities of IHA and DDIA are significant higher in 10-14 years old students than those of 7-9 years old group. The specificity of DDIA and IHA were 61% (95%CI: 49%-74%) and 72% (95%CI: 60%-84%), respectively. The co-infection with STHs decreased the specificity of DDIA but had no impact on that of IHA. Our study indicated that IHA has more potential as an alternative diagnostic tool for identifying schistosomiasis haematobium but need further improvement.
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Affiliation(s)
- Li-Juan Zhang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, PR China; WHO Collaborating Center for Tropical Diseases, Shanghai, PR China; National Center for International Research on Tropical Diseases, Shanghai, PR China; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, PR China
| | | | - Jing Xu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, PR China; WHO Collaborating Center for Tropical Diseases, Shanghai, PR China; National Center for International Research on Tropical Diseases, Shanghai, PR China; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, PR China.
| | - Le-Ping Sun
- Institute for Schistosomiasis Control, Wuxi, Jiangsu, PR China
| | - Xiao-Mei Yin
- Institute for Schistosomiasis Control, Hefei, Anhui, PR China
| | - Jian-Feng Zhang
- Institute for Schistosomiasis Control, Wuxi, Jiangsu, PR China
| | - Ming-Chuang Hu
- Institute for Schistosomiasis Control, Hefei, Anhui, PR China
| | - Wu-Min Si
- Institute for Schistosomiasis Control, Hefei, Anhui, PR China
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, PR China; WHO Collaborating Center for Tropical Diseases, Shanghai, PR China; National Center for International Research on Tropical Diseases, Shanghai, PR China; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, PR China.
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11
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Habib MR, Lv S, Guo YH, Gu WB, Standley CJ, Caldeira RL, Zhou XN. Morphological and molecular characterization of invasive Biomphalaria straminea in southern China. Infect Dis Poverty 2018; 7:120. [PMID: 30526682 PMCID: PMC6286595 DOI: 10.1186/s40249-018-0505-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Accepted: 11/15/2018] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Schistosomiasis is a common parasitic disease designated as a neglected tropical disease by the World Health Organization. Schistosomiasis mansoni is a form of the disease that is caused by the digenean trematode Schistosoma mansoni, transmitted through Biomphalaria spp. as an intermediate host. Biomphalaria was introduced to Hong Kong, China in aquatic plants shipments coming from Brazil and the snail rapidly established its habitats in southern China. Earlier studies of Biomphalaria spp. introduced to southern China identified the snails as Biomphalaria straminea, one of the susceptible species implicated in S. mansoni transmission in South America. However, recent molecular investigations also indicated the presence of another South American species, B. kuhniana, which is refractory to infection. As such, it is important to identify accurately the species currently distributed in southern China, especially with emerging reports of active S. mansoni infections in Chinese workers returning from Africa. METHODS We combined morphological and molecular taxonomy tools to precisely identify Biomphalaria spp. distributed in Guangdong Province, southern China. In order to clearly understand the molecular profile of the species, we constructed a phylogeny using mtDNA data (COI and 16S rRNA sequences) from six populations of Biomphalaria spp. from Shenzhen City in Guangdong Province. In addition, we examined the external morphology of the shell and internal anatomy of the reproductive organs. RESULTS Both morphological and molecular evidences indicated a close affinity between Biomphalaria spp. populations from Guangdong and B. straminea from Brazil. The shell morphology was roughly identical in all the populations collected with rounded whorls on one side and subangulated on the other, a smooth periphery, an egg-shaped aperture bowed to one side, and a deep umbilicus. The shape and number of prostate diverticula (ranged from 11.67 to 17.67) in Guangdong populations supports its close affinity to B. straminea rather than B. kuhniana. Molecular analysis did not conflict with morphological analysis. Little genetic differentiation was observed within Biomphalaria populations collected. Phylogenetic analysis of COI and 16S rRNA haplotypes from snails collected and B. straminea sequences from Brazil and China using Bayesian inference revealed that Guangdong populations were clustered in one clade with B. straminea from Hong Kong of China and B. straminea from Brazil indicating their close affinity to each other. CONCLUSIONS Data obtained in the current study clearly show that the populations of Biomphalaria spp. investigated are B. straminea, and we assume that those snails were either introduced via passive dispersal from Hong Kong of China or as a result of multiple introduction routes from Brazil.
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Affiliation(s)
- Mohamed R. Habib
- Medical Malacology Laboratory, Theodor Bilharz Research Institute, Giza, 12411 Egypt
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, 200025 China
- Chinese Center for Tropical Diseases Research; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology, Shanghai, 200025 China
| | - Shan Lv
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, 200025 China
- Chinese Center for Tropical Diseases Research; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology, Shanghai, 200025 China
| | - Yun-Hai Guo
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, 200025 China
- Chinese Center for Tropical Diseases Research; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology, Shanghai, 200025 China
| | - Wen-Biao Gu
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, 200025 China
- Chinese Center for Tropical Diseases Research; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology, Shanghai, 200025 China
| | - Claire J. Standley
- Milken Institute, School of Public Health, George Washington University, Washington, D.C, 20052 USA
| | - Roberta L. Caldeira
- Grupo de Pesquisas em Helmintologia e Malacologia Médica, Instituto René Rachou/Fiocruz, Av. Augusto de Lima, Belo Horizonte, MG 1715 Brazil
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, 200025 China
- Chinese Center for Tropical Diseases Research; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology, Shanghai, 200025 China
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12
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Yang Y, Huang SY, Pei FQ, Chen Y, Jiang QW, Deng ZH, Zhou YB. Spatial distribution and habitat suitability of Biomphalaria straminea, intermediate host of Schistosoma mansoni, in Guangdong, China. Infect Dis Poverty 2018; 7:109. [PMID: 30392469 PMCID: PMC6217779 DOI: 10.1186/s40249-018-0492-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 10/11/2018] [Indexed: 11/25/2022] Open
Abstract
Background Biomphalaria straminea is an invasive vector in China, posing a significant threat to public health. Understanding the factors affecting the establishment of this snail is crucial to improve our ability to manage its dispersal and potential risk of schistosomiasis transmission. This study sought to determine the spatial distribution of B. straminea in mainland China and whether environmental factors were divergent between places with and without B. straminea. Methods A malacological survey of B. straminea was conducted in Guangdong Province, China. Snails were identified using anatomical keys. Water and sediment samples were taken, and their physicochemical properties were analyzed using national standard methods. Landscape and climatic variables were also collected for each site. We compared the environmental characteristics between sites with and without B. straminea using Mann-Whitney U test. We further used generalized linear mixed models to account for seasonal effects. Results B. straminea was found at six sites, including one in Dongguan and five in Shenzhen. Probability map found a hot spot of B. straminea distribution at Shenzhen and Hong Kong. Sites occupied by B. straminea were characterized by higher median altitude, mean annual precipitation and moderate temperature. Water with snails had higher median concentrations of total nitrogen, nitrate and nitrites, ammoniacal nitrogen, calcium, zinc and manganese but lower dissolved oxygen and magnesium. Sediments with snails had higher median copper, zinc and manganese. B. straminea was associated with maximum temperature of the warmest month (pMCMC < 0.001) and sediment zinc (pMCMC < 0.001). Conclusions B. straminea is distributed in Shenzhen and its surrounding areas in Guangdong, China. Sites with and without B. straminea differed in the maximum temperature of the warmest month and sediment zinc. Surveillance should be continued to monitor the dispersal of this snail in China. Electronic supplementary material The online version of this article (10.1186/s40249-018-0492-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ya Yang
- Key Laboratory of Public Health Safety, Ministry of Education, Tropical Disease Research Center, Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
| | - Shao-Yu Huang
- Guangdong Provincial Center for Disease Control and Prevention, WHO Collaborating Centre for Surveillance, Research and Training of Emerging Infectious Diseases, Guangzhou, Guangdong, China
| | - Fu-Quan Pei
- Guangdong Provincial Center for Disease Control and Prevention, WHO Collaborating Centre for Surveillance, Research and Training of Emerging Infectious Diseases, Guangzhou, Guangdong, China
| | - Yue Chen
- School of Epidemiology and Public Health, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Qing-Wu Jiang
- Key Laboratory of Public Health Safety, Ministry of Education, Tropical Disease Research Center, Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
| | - Zhuo-Hui Deng
- Guangdong Provincial Center for Disease Control and Prevention, WHO Collaborating Centre for Surveillance, Research and Training of Emerging Infectious Diseases, Guangzhou, Guangdong, China.
| | - Yi-Biao Zhou
- Key Laboratory of Public Health Safety, Ministry of Education, Tropical Disease Research Center, Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China.
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13
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Song LG, Zeng XD, Li YX, Zhang BB, Wu XY, Yuan DJ, He A, Wu ZD. Imported parasitic diseases in mainland China: current status and perspectives for better control and prevention. Infect Dis Poverty 2018; 7:78. [PMID: 30071901 PMCID: PMC6091017 DOI: 10.1186/s40249-018-0454-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 06/19/2018] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND The high prevalence of parasitic diseases leads to millions of deaths and disabilities each year in developing countries. China has also been greatly affected by parasitic infections, including filariasis, leishmaniasis, malaria, schistosomiasis, and soil-transmitted nematodosis. However, the situation in China improved dramatically after comprehensive parasitic disease control efforts were strengthened, leading to the elimination of filariasis in 2006 and to significant control over other diseases. However, imported parasitic disease cases are inevitable, and such cases have increasingly been reported as a result of enhanced globalization and international or regional cooperation. These imported diseases represent a major obstacle to the elimination of several parasitoses, such as malaria. MAIN TEXT This paper reviews imported cases of parasitic diseases in mainland China, particularly malaria and schistosomiasis, based on data reported separately by the Chinese annual reports and from other published papers. We summarize the new challenges that face parasitic disease control efforts in mainland China and perspectives regarding better control. We argue that both the provision of professional education and updated training for medical care personnel and the management and surveillance of people entering China are essential. We recommend that Chinese migrant workers should be considered a priority group for health education and that public awareness of imported diseases should be emphasized. Furthermore, we underscore the importance of investigating the distribution of introduced/potential vectors, parasite susceptibility, and improvements in diagnostic techniques and drug stocks. CONCLUSIONS Imported cases have become the main challenge to the elimination of several parasitoses, such as malaria and schistosomiasis, in mainland China. China should act to meet these challenges, which are closely associated with national biological safety.
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Affiliation(s)
- Lan-Gui Song
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 Guangdong China
- Key Laboratory of Tropical Diseases Control (SYSU), Ministry of Education, Guangzhou, 510080 Guangdong China
- Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080 Guangdong China
| | - Xing-Da Zeng
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 Guangdong China
- Key Laboratory of Tropical Diseases Control (SYSU), Ministry of Education, Guangzhou, 510080 Guangdong China
- Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080 Guangdong China
| | - Yan-Xia Li
- Jiangxi Provincial Testing Center of Medical Apparatus and Instruments, Nanchang, 330029 Jiangxi China
| | - Bei-Bei Zhang
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 Guangdong China
- Key Laboratory of Tropical Diseases Control (SYSU), Ministry of Education, Guangzhou, 510080 Guangdong China
- Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080 Guangdong China
| | - Xiao-Ying Wu
- School of Public Health, Fudan University, Shanghai, 200433 China
| | - Dong-Juan Yuan
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 Guangdong China
- Key Laboratory of Tropical Diseases Control (SYSU), Ministry of Education, Guangzhou, 510080 Guangdong China
- Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080 Guangdong China
| | - Ai He
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 Guangdong China
- Key Laboratory of Tropical Diseases Control (SYSU), Ministry of Education, Guangzhou, 510080 Guangdong China
- Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080 Guangdong China
| | - Zhong-Dao Wu
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080 Guangdong China
- Key Laboratory of Tropical Diseases Control (SYSU), Ministry of Education, Guangzhou, 510080 Guangdong China
- Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080 Guangdong China
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Li Y, Teng Z, Ruan S, Li M, Feng X. A mathematical model for the seasonal transmission of schistosomiasis in the lake and marshland regions of China. MATHEMATICAL BIOSCIENCES AND ENGINEERING : MBE 2018; 14:1279-1299. [PMID: 29161861 DOI: 10.3934/mbe.2017066] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Schistosomiasis, a parasitic disease caused by \textit{ Schistosoma Japonicum}, is still one of the most serious parasitic diseases in China and remains endemic in seven provinces, including Hubei, Anhui, Hunan, Jiangsu, Jiangxi, Sichuan, and Yunnan. The monthly data of human schistosomiasis cases in Hubei, Hunan, and Anhui provinces (lake and marshland regions) released by the Chinese Center for Disease Control and Prevention (China CDC) display a periodic pattern with more cases in late summer and early autumn. Based on this observation, we construct a deterministic model with periodic transmission rates to study the seasonal transmission dynamics of schistosomiasis in these lake and marshland regions in China. We calculate the basic reproduction number R0, discuss the dynamical behavior of solutions to the model, and use the model to fit the monthly data of human schistosomiasis cases in Hubei. We also perform some sensitivity analysis of the basic reproduction number R0 in terms of model parameters. Our results indicate that treatment of at-risk population groups, improving sanitation, hygiene education, and snail control are effective measures in controlling human schistosomiasis in these lakes and marshland regions.
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Affiliation(s)
- Yingke Li
- College of Mathematics and System Sciences, Xinjiang University, Urumqi, Xinjiang 830046, China
| | - Zhidong Teng
- College of Mathematics and System Sciences, Xinjiang University, Urumqi, Xinjiang 830046, China
| | - Shigui Ruan
- Department of Mathematics, University of Miami, Coral Gables, FL 33146, United States
| | - Mingtao Li
- Complex Systems Research Center, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Xiaomei Feng
- Department of Mathematics, Yuncheng University, Yuncheng, Shanxi 044000, China
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15
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Sanogo B, Yuan D, Zeng X, Zhang Y, Wu Z. RETRACTED: Diversity and Compatibility of Human Schistosomes and Their Intermediate Snail Hosts. Trends Parasitol 2018; 34:493-510. [PMID: 29627269 DOI: 10.1016/j.pt.2018.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Revised: 02/22/2018] [Accepted: 03/15/2018] [Indexed: 01/13/2023]
Abstract
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal) This article has been retracted at the request of the authors: Benjamin Sanogo, Dongjuan Yuan, Xin Zeng, Yanhua Zhang, and Zhongdao Wu. Our article reviews the evolution, geography, diversity, genetics and host-compatibility of human schistosomes and their hosts. It has come to our attention that readers have found some of the content in the article to be confusing or misleading. As authors, we have tried our best to share our scientific discovery and understanding faithfully, but we also agree that scientific reports should stand up to doubt and discussion. After serious consideration, to avoid confusion in the Schistosoma research community, we are retracting the Review. We apologize to the community for any inconvenience we have caused.
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Affiliation(s)
- Benjamin Sanogo
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; Key Laboratory for Tropical Diseases Control (SYSU), Ministry of Education, Guangzhou 510080, China; Provincial Engineering Technology Research Center for Diseases-vectors Control, Guangdong, Guangzhou 510080, China
| | - Dongjuan Yuan
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; Key Laboratory for Tropical Diseases Control (SYSU), Ministry of Education, Guangzhou 510080, China; Provincial Engineering Technology Research Center for Diseases-vectors Control, Guangdong, Guangzhou 510080, China
| | - Xin Zeng
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; Key Laboratory for Tropical Diseases Control (SYSU), Ministry of Education, Guangzhou 510080, China; Provincial Engineering Technology Research Center for Diseases-vectors Control, Guangdong, Guangzhou 510080, China
| | - Yanhua Zhang
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; Key Laboratory for Tropical Diseases Control (SYSU), Ministry of Education, Guangzhou 510080, China; Provincial Engineering Technology Research Center for Diseases-vectors Control, Guangdong, Guangzhou 510080, China
| | - Zhongdao Wu
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China; Key Laboratory for Tropical Diseases Control (SYSU), Ministry of Education, Guangzhou 510080, China; Provincial Engineering Technology Research Center for Diseases-vectors Control, Guangdong, Guangzhou 510080, China
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16
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Yang Y, Cheng W, Wu X, Huang S, Deng Z, Zeng X, Yuan D, Yang Y, Wu Z, Chen Y, Zhou Y, Jiang Q. Prediction of the potential global distribution for Biomphalaria straminea, an intermediate host for Schistosoma mansoni. PLoS Negl Trop Dis 2018; 12:e0006548. [PMID: 29813073 PMCID: PMC5993297 DOI: 10.1371/journal.pntd.0006548] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 06/08/2018] [Accepted: 05/21/2018] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Schistosomiasis is a snail-borne parasitic disease and is endemic in many tropical and subtropical countries. Biomphalaria straminea, an intermediate host for Schistosoma mansoni, is native to the southeastern part of South America and has established in other regions of South America, Central America and southern China during the last decades. S. mansoni is endemic in Africa, the Middle East, South America and the Caribbean. Knowledge of the potential global distribution of this snail is essential for risk assessment, monitoring, disease prevention and control. METHODS AND FINDINGS A comprehensive database of cross-continental occurrence for B. straminea was compiled to construct ecological models. We used several approaches to investigate the distribution of B. straminea, including direct comparison of climatic conditions, principal component analysis and niche overlap analyses to detect niche shifts. We also investigated the impacts of bioclimatic and human factors, and then used the bioclimatic and footprint layers to predict the potential distribution of B. straminea at global scale. We detected niche shifts accompanying the invasions of B. straminea in the Americas and China. The introduced populations had enlarged its habitats to subtropical regions where annual mean temperature is relatively low. Annual mean temperature, isothermality and temperature seasonality were identified as most important climatic features for the occurrence of B. straminea. Additionally, human factors improved the model prediction (P<0.001). Our model showed that under current climate conditions the snail should mostly be confined to the tropic and subtropic regions, including South America, Central America, Sub-Saharan Africa and Southeast Asia. CONCLUSIONS Our results confirmed that niche shifts took place in the invasions of B. straminea, in which bioclimatic and human factors played an important role. Our model predicted the global distribution of B. straminea based on habitat suitability, which would help for prioritizing monitoring and management efforts for B. straminea control in the context of ongoing climate change and human disturbances.
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Affiliation(s)
- Ya Yang
- Key Laboratory of Public Health Safety, Ministry of Education, Tropical Disease Research Center, Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
| | - Wanting Cheng
- Key Laboratory of Public Health Safety, Ministry of Education, Tropical Disease Research Center, Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
| | - Xiaoying Wu
- Key Laboratory of Public Health Safety, Ministry of Education, Tropical Disease Research Center, Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
| | - Shaoyu Huang
- Institute of Parasitic Diseases, Guangdong Provincial Center for Disease Control and Prevention, Guangdong, China
| | - Zhuohui Deng
- Institute of Parasitic Diseases, Guangdong Provincial Center for Disease Control and Prevention, Guangdong, China
| | - Xin Zeng
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong, China
| | - Dongjuan Yuan
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong, China
| | - Yu Yang
- Key Laboratory of Public Health Safety, Ministry of Education, Tropical Disease Research Center, Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
| | - Zhongdao Wu
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong, China
| | - Yue Chen
- School of Epidemiology and Public Health, Faculty of Medicine, University of Ottawa, Ottawa, Canada
| | - Yibiao Zhou
- Key Laboratory of Public Health Safety, Ministry of Education, Tropical Disease Research Center, Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
- * E-mail:
| | - Qingwu Jiang
- Key Laboratory of Public Health Safety, Ministry of Education, Tropical Disease Research Center, Department of Epidemiology, School of Public Health, Fudan University, Shanghai, China
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17
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Wang W, Mao Q, Yao J, Yang W, Zhang Q, Lu W, Deng Z, Duan L. Discovery of the pyridylphenylureas as novel molluscicides against the invasive snail Biomphalaria straminea, intermediate host of Schistosoma mansoni. Parasit Vectors 2018; 11:291. [PMID: 29743096 PMCID: PMC5944108 DOI: 10.1186/s13071-018-2868-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 04/23/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The snail Biomphalaria straminea is one of the intermediate hosts of Schistosoma mansoni. Biomphalaria straminea is also an invasive species, known for its strong capability on peripheral expansion, long-distance dispersal and colonization. Using molluscicides to control snail populations is an important strategy to interrupt schistosomiasis transmission and to prevent the spread of the invasive species. In this study, a series of pyridylphenylurea derivatives were synthesized as potential molluscicides. Their impact on adult snails and egg masses was evaluated. Acute toxicity to fish of the derivatives was also examined to assess their effect on non-target organisms. The preliminary mechanisms of action of the derivatives were studied by enzyme activity assays. RESULTS The representative compounds, 1-(4-chlorophenyl)-3-(pyridin-3-yl)urea (compound 8) and 1-(4-bromophenyl)-3-(pyridin-3-yl)urea (compound 9), exhibited strong molluscicidal activity against adult snails with LD50 values of 0.50 and 0.51 mg/l and potent inhibitory effects on snail egg hatchability with IC50 values of 0.05 and 0.09 mg/l. Notably, both compounds showed good target specificity with potent molluscicidal capability observed in snails, but very low toxicity to local fishes. Furthermore, the exposure of compounds 8 and 9 significantly elevated the enzyme activities of acid phosphatase and nitric oxide synthase of the snails, while no significant change was recorded in the activities of alkaline phosphatase, acetylcholine esterase and superoxide dismutase. CONCLUSION The results suggested that compounds 8 and 9 of pyridylphenylurea derivatives could be developed as promising molluscicide candidates for snail control.
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Affiliation(s)
- Weisi Wang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Key Laboratory of Parasitology and Vector Biology of the Chinese Ministry of Health, Shanghai, 200025, China
| | - Qiang Mao
- Guangdong Provincial Center for Disease Control and Prevention, WHO Collaborating Centre for Surveillance, Research and Training of Emerging Infectious Diseases, Guangzhou, 511430, Guangdong, China
| | - Junmin Yao
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Key Laboratory of Parasitology and Vector Biology of the Chinese Ministry of Health, Shanghai, 200025, China
| | - Weijia Yang
- College of Life and Environmental Sciences, Shanghai Normal University, Shanghai, 200234, China
| | - Qiming Zhang
- Guangdong Provincial Center for Disease Control and Prevention, WHO Collaborating Centre for Surveillance, Research and Training of Emerging Infectious Diseases, Guangzhou, 511430, Guangdong, China
| | - Wencheng Lu
- Guangdong Provincial Center for Disease Control and Prevention, WHO Collaborating Centre for Surveillance, Research and Training of Emerging Infectious Diseases, Guangzhou, 511430, Guangdong, China
| | - Zhuohui Deng
- Guangdong Provincial Center for Disease Control and Prevention, WHO Collaborating Centre for Surveillance, Research and Training of Emerging Infectious Diseases, Guangzhou, 511430, Guangdong, China.
| | - Liping Duan
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Centre for Malaria, Schistosomiasis and Filariasis, Key Laboratory of Parasitology and Vector Biology of the Chinese Ministry of Health, Shanghai, 200025, China. .,Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
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Molluscicidal activity and mechanism of toxicity of a novel salicylanilide ester derivative against Biomphalaria species. Parasit Vectors 2017; 10:383. [PMID: 28793917 PMCID: PMC5550999 DOI: 10.1186/s13071-017-2313-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Accepted: 07/27/2017] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Schistosomiasis mansoni is one of the most important, but often neglected, tropical diseases transmitted by snails of the genus Biomphalaria. Control of the intermediate host snail plays a crucial role in preventing the spread of schistosomiasis. However, there is only one molluscicide, niclosamide, recommended by the World Health Organization. Niclosamide has been used for several decades but is toxic to non-target organisms. Therefore, it is necessary to optimize the scaffold of niclosamide and develop novel molluscicides with enhanced potency and decreased toxicity to non-target organisms. METHODS In this study, a candidate compound was analyzed by nuclear magnetic resonance and mass spectrometry. The molluscicidal potential against Biomphalaria species and cercaricidal potential against S. mansoni were evaluated using the immersion method. Furthermore, the preliminary mechanism was studied through cellular enzyme tests and electron microscopy. RESULTS 5-chloro-2-[(2-chloro-4-nitrophenyl)carbamoyl]phenyl-4-methoxybenzoate (salicylanilidate), a novel salicylanilide ester derivative, was derived from niclosamide. The 50% lethal concentration to B. glabrata, B. straminea and B. pfeifferi was 0.261 mg/l, 0.172 mg/l and 0.241 mg/l, respectively. The effective dose required to completely kill S. mansoni cercariae was 0.625 mg/l for salicylanilidate and 0.125 mg/l for niclosamide. However, salicylanilidate was approximately 100-fold less toxic to the fish Danio rerio than niclosamide. Furthermore, salicylanilidate reduced the enzymatic activities of nitric oxide synthase (NOS), lactate dehydrogenase (LDH) and acetylcholinesterase (AChE) in the snail, demonstrating that it could affect neurohypophysis transmission and energy metabolism. Severe swelling in the tentacle and deformation of cilia in the tentacle and mantle were observed through scanning electron microscopy. The results of transmission electron microscopy showed that salicylanilidate could damage critical organelles in hepatopancreas tissues, including degeneration of the endoplasmic reticulum and vacuolization in mitochondria. In addition, transcriptional levels of superoxide dismutase (SOD), acid phosphatase (ACP) and NOS in the hepatopancreas were significantly downregulated as shown by real-time quantitative polymerase chain reaction (RT-PCR). These results indicated that the hepatopancreas is a primary target organ of salicylanilidate. CONCLUSIONS Salicylanilidate not only had deleterious effects on Biomphalaria species and S. mansoni cercariae but also showed very low toxicity to D. rerio, suggesting that it has broad potential applications.
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Zeng X, Yiu WC, Cheung KH, Yip HY, Nong W, He P, Yuan D, Rollinson D, Qiu JW, Fung MC, Wu Z, Hui JHL. Distribution and current infection status of Biomphalaria straminea in Hong Kong. Parasit Vectors 2017; 10:351. [PMID: 28743308 PMCID: PMC5526268 DOI: 10.1186/s13071-017-2285-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 07/12/2017] [Indexed: 03/11/2023] Open
Abstract
Background Schistosomiasis, also generally known as snail fever, is a parasitic disease caused by trematode flatworms of the genus Schistosoma. In Hong Kong and mainland China, the freshwater snail Biomphalaria straminea has been introduced and has the potential to transmit intestinal schistosomiasis caused by S. mansoni, a parasite of man which has a wide distribution in Africa and parts of the New World, especially Brazil. The first identification of B. straminea in Hong Kong dates back to the 1970s, and its geographical distribution, phylogenetic relationships, and infection status have not been updated for more than 30 years. Thus, this study aims to reveal the distribution and current infection status of B. straminea in contemporary Hong Kong. Methods Snails were collected from different parts of Hong Kong from July 2016 to January 2017. Both anatomical and molecular methods were applied to identify B. straminea. Cytochrome c oxidase subunit 1 (cox1), internal transcribed spacer 1 (ITS1), 5.8S rDNA, internal transcribed spacer 2 (ITS2), and 16S ribosomal DNA (rDNA) were sequenced from individual snails and analyzed. To detect the presence of S. mansoni, both biopsy and PCR analyses were carried out. Results Using both anatomical and molecular analyses, this study demonstrated the existence of black- and red-coloured shell B. straminea in different districts in the New Territories in Hong Kong, including places close to the mainland China border. None of the B. straminea (n = 87) investigated were found to be infected with S. mansoni when tested by biopsy and PCR. The Hong Kong B. straminea are genetically indistinguishable, based on the chosen molecular markers (cox1, ITS1-5.8S-ITS2, and 16S rDNA), and are similar to those obtained in mainland China and South America. Conclusion Biomphalaria straminea is now well established in freshwater habitats in Hong Kong. No evidence of infection with S. mansoni has been found. Surveillance should be continued to monitor and better understand this schistosomiasis intermediate host in mainland China and Hong Kong. Electronic supplementary material The online version of this article (doi:10.1186/s13071-017-2285-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xin Zeng
- School of Life Science, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China.,Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong Province, People's Republic of China.,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, Guangdong Province, People's Republic of China
| | - Wing Chung Yiu
- School of Life Science, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China
| | - Kwan Ho Cheung
- School of Life Science, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China
| | - Ho Yin Yip
- School of Life Science, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China
| | - Wenyan Nong
- School of Life Science, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China
| | - Ping He
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong Province, People's Republic of China.,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, Guangdong Province, People's Republic of China
| | - Dongjuan Yuan
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong Province, People's Republic of China.,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, Guangdong Province, People's Republic of China
| | - David Rollinson
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, UK
| | - Jian-Wen Qiu
- Department of Biology, Hong Kong Baptist University, Hong Kong, Special Administrative Region, People's Republic of China
| | - Ming Chiu Fung
- School of Life Science, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China.,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, Guangdong Province, People's Republic of China
| | - Zhongdao Wu
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong Province, People's Republic of China. .,Key Laboratory of Tropical Disease Control (SYSU), Ministry of Education, Guangzhou, Guangdong Province, People's Republic of China.
| | - Jerome Ho Lam Hui
- School of Life Science, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China.
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Wang W, Chen J, Sheng HF, Wang NN, Yang P, Zhou XN, Bergquist R. Infectious Diseases of Poverty, the first five years. Infect Dis Poverty 2017; 6:96. [PMID: 28472981 PMCID: PMC5415955 DOI: 10.1186/s40249-017-0310-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 04/25/2017] [Indexed: 12/15/2022] Open
Abstract
Although the focus in the area of health research may be shifting from infectious to non-communicable diseases, the infectious diseases of poverty remain a major burden of disease of global health concern. A global platform to communicate and share the research on these diseases is needed to facilitate the translation of knowledge into effective approaches and tools for their elimination. Based on the “One health, One world” mission, a new, open-access journal, Infectious Diseases of Poverty (IDP), was launched by BioMed Central in partnership with the National Institute of Parasitic Diseases (NIPD), Chinese Center for Disease Control and Prevention (China CDC) on October 25, 2012. Its aim is to identify and assess research and information gaps that hinder progress towards new interventions for a particular public health problem in the developing world. From the inaugural IDP issue of October 25, 2012, a total of 256 manuscripts have been published over the following five years. Apart from a small number of editorials, opinions, commentaries and letters to the editor, the predominant types of publications are research articles (69.5%) and scoping reviews (21.5%). A total of 1 081 contributing authors divided between 323 affiliations across 68 countries, territories and regions produced these 256 publications. The journal is indexed in major international biomedical databases, including Web of Science, PubMed, Scopus and Embase. In 2015, it was assigned its first impact factor (4.11), which is now 2.13. During the past five years, IDP has received manuscripts from 90 countries, territories and regions across six continents with an annual acceptance rate of all contributions maintained at less than 40%. Content analysis shows that neglected tropical diseases (NTDs), followed by the “Big Three” (HIV/AIDS, malaria and tuberculosis) and infectious diseases in general comprise 88% of all publications. In addition, a series of 10 thematic issues, covering 118 publications in all, was published as separate parts of the first five volumes. These publications were cited 975 times, which equals an average of 8.3 times per publication. The current challenge is to identify cutting-edge research topics and attract and to publish first-rate publications leading to increasing importance and impact of the journal in its field.
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Affiliation(s)
- Wei Wang
- Key Laboratory of National Health and Family Planning Commission on Parasitic Disease Control and Prevention, No. 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China.,Jiangsu Provincial Key Laboratory on Parasites and Vector Control Technology, No. 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China.,Jiangsu Institute of Parasitic Diseases, No. 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China.,School of Public Health, Fujian Medical University, No. 88 Jiaotong Road, Fuzhou City, Fujian Province, 350004, China
| | - Jin Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, No. 207 Rui Jin Er Road, Shanghai, 200025, China.,WHO Collaborating Center for Tropical Diseases, No. 207 Rui Jin Er Road, Shanghai, 200025, China.,Key Laboratory of Parasite and Vector Biology, Ministry of Health, No. 207 Rui Jin Er Road, Shanghai, 200025, China
| | - Hui-Feng Sheng
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, No. 207 Rui Jin Er Road, Shanghai, 200025, China.,WHO Collaborating Center for Tropical Diseases, No. 207 Rui Jin Er Road, Shanghai, 200025, China.,Key Laboratory of Parasite and Vector Biology, Ministry of Health, No. 207 Rui Jin Er Road, Shanghai, 200025, China
| | - Na-Na Wang
- Editorial Office of Chinese Journal of Clinical Research, No. 57 Shanxi Road, Nanjing City, Jiangsu Province, 210009, China
| | - Pin Yang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, No. 207 Rui Jin Er Road, Shanghai, 200025, China. .,WHO Collaborating Center for Tropical Diseases, No. 207 Rui Jin Er Road, Shanghai, 200025, China. .,Key Laboratory of Parasite and Vector Biology, Ministry of Health, No. 207 Rui Jin Er Road, Shanghai, 200025, China.
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, No. 207 Rui Jin Er Road, Shanghai, 200025, China.,WHO Collaborating Center for Tropical Diseases, No. 207 Rui Jin Er Road, Shanghai, 200025, China.,Key Laboratory of Parasite and Vector Biology, Ministry of Health, No. 207 Rui Jin Er Road, Shanghai, 200025, China
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Cheng G, Li D, Zhuang D, Wang Y. The influence of natural factors on the spatio-temporal distribution of Oncomelania hupensis. Acta Trop 2016; 164:194-207. [PMID: 27659095 DOI: 10.1016/j.actatropica.2016.09.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 09/07/2016] [Accepted: 09/17/2016] [Indexed: 01/19/2023]
Abstract
BACKGROUND We analyzed the influence of natural factors, such as temperature, rainfall, vegetation and hydrology, on the spatio-temporal distribution of Oncomelania hupensis and explored the leading factors influencing these parameters. The results will provide reference methods and theoretical a basis for the schistosomiasis control. METHODS GIS (Geographic Information System) spatial display and analysis were used to describe the spatio-temporal distribution of Oncomelania hupensis in the study area (Dongting Lake in Hunan Province) from 2004 to 2011. Correlation analysis was used to detect the natural factors associated with the spatio-temporal distribution of O. hupensis. Spatial regression analysis was used to quantitatively analyze the effects of related natural factors on the spatio-temporal distribution of snails and explore the dominant factors influencing this parameter. RESULTS (1) Overall, the spatio-temporal distribution of O. hupensis was governed by the comprehensive effects of natural factors. In the study area, the average density of living snails showed a downward trend, with the exception of a slight rebound in 2009. The density of living snails showed significant spatial clustering, and the degree of aggregation was initially weak but enhanced later. Regions with high snail density and towns with an HH distribution pattern were mostly distributed in the plain areas in the northwestern and inlet and outlet of the lake. (2) There were space-time differences in the influence of natural factors on the spatio-temporal distribution of O. hupensis. Temporally, the comprehensive influence of natural factors on snail distribution increased first and then decreased. Natural factors played an important role in snail distribution in 2005, 2006, 2010 and 2011. Spatially, it decreased from the northeast to the southwest. Snail distributions in more than 20 towns located along the Yuanshui River and on the west side of the Lishui River were less affected by natural factors, whereas relatively larger in areas around the outlet of the lake (Chenglingji) were more affected. (3) The effects of natural factors on the spatio-temporal distribution of O. hupensis were spatio-temporally heterogeneous. Rainfall, land surface temperature, NDVI, and distance from water sources all played an important role in the spatio-temporal distribution of O. hupensis. In addition, due to the effects of the local geographical environment, the direction of the influences the average annual rainfall, land surface temperature, and NDVI had on the spatio-temporal distribution of O. hupensis were all spatio-temporally heterogeneous, and both the distance from water sources and the history of snail distribution always had positive effects on the distribution O. hupensis, but the direction of the influence was spatio-temporally heterogeneous. (4) Of all the natural factors, the leading factors influencing the spatio-temporal distribution of O. hupensis were rainfall and vegetation (NDVI), and the primary factor alternated between these two. The leading role of rainfall decreased year by year, while that of vegetation (NDVI) increased from 2004 to 2011. CONCLUSIONS The spatio-temporal distribution of O. hupensis was significantly influenced by natural factors, and the influences were heterogeneous across space and time. Additionally, the variation in the spatial-temporal distribution of O. hupensis was mainly affected by rainfall and vegetation.
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Qu G, Wang W, Lu X, Dai J, Li X, Liang Y. Evaluating the risk of Schistosoma mansoni transmission in mainland China. Parasitol Res 2016; 115:4711-4713. [PMID: 27637225 DOI: 10.1007/s00436-016-5243-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 09/02/2016] [Indexed: 11/26/2022]
Abstract
Biomphalaria straminea, an intermediate host of Schistosoma mansoni, is predominantly distributed in the South Americas and Caribbean; however, this snail, as an invasive species, was introduced to Shenzhen, southern China, in 1981, and recent epidemiologic surveys demonstrate that the distribution of B. straminea has expanded across the Zhujiang River Basin, South China. In the presence of continuous importation of S. mansoni-infected cases, there is a growing concern about the transmission of S. mansoni in China. To evaluate the risk of S. mansoni transmission in China, we tested the compatibility of B. straminea captured from the snail habitats in southern China with S. mansoni in laboratory. We detected no S. mansoni infections in B. straminea following exposure to the parasite larvae at snail/miracidium ratios of 1:5, 1:10, 1:20, 1:40, and 1:80, while 6.7 to 66.7 % infections occurred in the control Biomphalaria glabrata depending on the ratio. The results of the present study demonstrate that the invasive B. straminea snails seem to be incompatible with S. mansoni, suggesting a low risk of S. mansoni transmission in mainland China.
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Affiliation(s)
- Guoli Qu
- Key Laboratory of National Health and Family Planning Commission on Parasitic Disease Control and Prevention, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China
- Jiangsu Provincial Key Laboratory on Parasites and Vector Control Technology, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China
- Jiangsu Institute of Parasitic Diseases, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China
| | - Wei Wang
- Key Laboratory of National Health and Family Planning Commission on Parasitic Disease Control and Prevention, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China.
- Jiangsu Provincial Key Laboratory on Parasites and Vector Control Technology, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China.
- Jiangsu Institute of Parasitic Diseases, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China.
| | - Xiaomin Lu
- Wuxi No. 2 People's Hospital, No. 68 Zhongshan Road, Wuxi City, Jiangsu Province, 214002, China
| | - Jianrong Dai
- Key Laboratory of National Health and Family Planning Commission on Parasitic Disease Control and Prevention, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China
- Jiangsu Provincial Key Laboratory on Parasites and Vector Control Technology, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China
- Jiangsu Institute of Parasitic Diseases, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China
| | - Xiaoheng Li
- Shenzhen Center for Disease Control and Prevention, No. 8 Longyuan Road, Nanshan District, Shenzhen City, Guangdong Province, 518055, China
| | - Yousheng Liang
- Key Laboratory of National Health and Family Planning Commission on Parasitic Disease Control and Prevention, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China.
- Jiangsu Provincial Key Laboratory on Parasites and Vector Control Technology, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China.
- Jiangsu Institute of Parasitic Diseases, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province, 214064, China.
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Bian CR, Lu DB, Su J, Zhou X, Zhuge HX, Lamberton PHL. Serological Prevalence of Schistosoma japonicum in Mobile Populations in Previously Endemic but Now Non-Endemic Regions of China: A Systematic Review and Meta-Analysis. PLoS One 2015; 10:e0128896. [PMID: 26043190 PMCID: PMC4456376 DOI: 10.1371/journal.pone.0128896] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Accepted: 05/03/2015] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Schistosomiasis japonica has been resurging in certain areas of China where its transmission was previously well controlled or interrupted. Several factors may be contributing to this, including mobile populations, which if infected, may spread the disease. A wide range of estimates have been published for S. japonicum infections in mobile populations, and a synthesis of these data will elucidate the relative risk presented from these groups. METHODS A literature search for publications up to Oct 31, 2014 on S. japonicum infection in mobile populations in previously endemic but now non-endemic regions was conducted using four bibliographic databases: China National Knowledge Infrastructure, WanFang, VIP Chinese Journal Databases, and PubMed. A meta-analysis was conducted by pooling one arm binary data with MetaAnalyst Beta 3.13. The protocol is available on PROSPERO (No. CRD42013005967). RESULTS A total of 41 studies in Chinese met the inclusion criteria, covering seven provinces of China. The time of post-interruption surveillance ranged from the first year to the 31st year. After employing a random-effects model, from 1992 to 2013 the pooled seroprevalence ranged from 0.9% (95% CI: 0.5-1.6%) in 2003 to 2.3% (95% CI: 1.5-3.4) in 1995; from the first year after the disease had been interrupted to the 31st year, the pooled seroprevalence ranged from 0.6% (95% CI: 0.2-2.1%) in the 27th year to 4.0% (95%CI: 1.3-11.3%) in the second year. The pooled seroprevalence in mobile populations each year was significantly lower than among the residents of endemic regions, whilst four papers reported a lower level of infection in the mobile populations than in the local residents out of only 13 papers which included this data. CONCLUSIONS The re-emergence of S. japonicum in areas which had previously interrupted transmission might be due to other factors, although risk from re-introduction from mobile populations could not be excluded.
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Affiliation(s)
- Chao-Rong Bian
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou 215123, China
| | - Da-Bing Lu
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou 215123, China
| | - Jing Su
- Department of Epidemiology and Statistics, School of Public Health, Soochow University, Suzhou 215123, China
| | - Xia Zhou
- Department of Parasitology, School of Biology and Basic Medical Sciences, Soochow University, Suzhou 215123, China
| | - Hong-Xiang Zhuge
- Department of Parasitology, School of Biology and Basic Medical Sciences, Soochow University, Suzhou 215123, China
| | - Poppy H. L. Lamberton
- Department of Infectious Disease Epidemiology, Imperial College London, London, W2 1PG, United Kingdom
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Zou L, Ruan S. Schistosomiasis transmission and control in China. Acta Trop 2015; 143:51-7. [PMID: 25559046 DOI: 10.1016/j.actatropica.2014.12.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Accepted: 12/06/2014] [Indexed: 11/24/2022]
Abstract
In the last 60 years, great progress has been made in controlling and preventing schistosomiasis in China. However, due to the ecosystem changes caused by the construction of the Three Gorges Dams and the South-north Water Conversion Project, the effects of climate change, the scarcity of a highly sensitive surveillance and response system, schistosomiasis is still considered as a major public health problem and is listed among the top infectious diseases in the country prioritized for control and elimination. Based on the epidemiological pattern of schistosomiasis and ecological characteristics of the vector snail, endemic areas of schistosomiasis in China were categorized into three types: (i) plain region with waterway networks, (ii) mountainous and hilly regions, and (iii) marshland and lake regions. China aims to reach the criteria of transmission control threshold of less than 1% in the lake and marshland provinces and reach transmission interruption threshold in hilly provinces of Sichuan and Yunnan by the end of 2015. The purpose of this article is to use the deterministic model proposed in our earlier study in (Chen et al., 2010) to simulate the schistosomiasis infection data from other lake and marshland provinces, including Hunan, Jiangxi and Anhui. Our simulations demonstrate that the model can reasonably mimic the schistosomiasis infection data from these lake and marshland provinces. Thus, similar control and prevention measures can be designed and proposed for these provinces. We will also try to use the model to simulate the schistosomiasis infection data from Sichuan and Yunnan provinces in the mountainous and hilly regions where cattle farming is not as popular and important as in the lake and marshland provinces and find out that different control and prevention strategies are required.
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Attwood SW, Huo GN, Qiu JW. Update on the distribution and phylogenetics of Biomphalaria (Gastropoda: Planorbidae) populations in Guangdong Province, China. Acta Trop 2015; 141:258-70. [PMID: 24811366 DOI: 10.1016/j.actatropica.2014.04.032] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 04/24/2014] [Accepted: 04/25/2014] [Indexed: 02/05/2023]
Abstract
In 1973 planorbid snails then identified as Biomphalaria straminea were discovered in Hong Kong, China. It was assumed that these snails had been introduced to Hong Kong via the import of tropical fish by air from South America. In 2012 Biomphalaria were found for the first time in Guangdong Province, China. In view of the renewed interest in these invasive snails, a morphological and DNA-sequence based phylogenetic study was undertaken for seven populations of Biomphalaria snails collected in Guangdong. Morphologically and phylogenetically, five of the populations clustered more closely with Biomphalaria kuhniana than with B. straminea. Levels of genetic diversity among the populations were about half those of autochthonous populations in Brazil, the phylogenetic relationships did not correlate with a radiation from any one international port in China, and different lineages appeared associated with different ports. Consequently in explaining the current distribution of the snails, multiple colonization events, each establishing a new local snail population near to maritime international container ports, were considered more likely than the spread of snails from Hong Kong to China. The displacement of B. straminea by B. kuhniana in Guangdong is considered as an explanation for the habitat changes observed among the snails between Hong Kong in the 1980s and the present. The conclusions of the study are that any risk of Schistosoma mansoni transmission in China is more likely to come from parasite importation in the intramolluscan stage, than from transmission by migrant workers from South America or Africa. In addition, although likely to be rare, sporadic outbreaks of imported schistosomiasis (caused by invading infected snails) could be a threat to public health in the vicinity of International container ports (not only in Guangdong Province). Further work is called for to investigate further the presence of B. kuhniana and its potential interactions with B. straminea (the former is thought to be incompatible with S. mansoni), and the responses of Chinese Biomphalaria to potential competitors such as Thiaridae. The current expansion of container ports in Brazil and Venezuela, and the increase in trade with China, is likely to accentuate any current risk of imported schistosomiasis, and surveillance around ports in China, together with further research, are necessary.
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Affiliation(s)
- Stephen W Attwood
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, People's Republic of China; Department of Life Sciences, The Natural History Museum, London, United Kingdom.
| | - Guan-Nan Huo
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, People's Republic of China
| | - Jian-Wen Qiu
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
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Compatibility of Schistosoma japonicum from the hilly region and Oncomelania hupensis hupensis from the marshland region within Anhui, China. Parasitol Res 2014; 113:4477-84. [DOI: 10.1007/s00436-014-4133-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 08/29/2014] [Indexed: 10/24/2022]
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Koriem KM, Shahabudin RE, Jamaludin RZ. Aristolochia gehrtii inhibits liver toxicity and apoptosis in Schistosoma malayensis infection. ASIAN PAC J TROP MED 2014. [DOI: 10.1016/s1995-7645(14)60117-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Wang W, Dai JR, Liang YS. Apropos: factors impacting on progress towards elimination of transmission of schistosomiasis japonica in China. Parasit Vectors 2014; 7:408. [PMID: 25175021 PMCID: PMC4261779 DOI: 10.1186/1756-3305-7-408] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 08/24/2014] [Indexed: 12/01/2022] Open
Abstract
Currently, China is moving towards the elimination of schistosomiasis japonica. In a previous review, the factors affecting the progress towards the elimination of transmission of schistosomiasis in China have been summarized. Nevertheless, some factors were neglected. Hereby, we describe four other factors which may threaten the achievement of the goal of schistosomiasis elimination in China.
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Affiliation(s)
- Wei Wang
- Jiangsu Institute of Parasitic Diseases, 117 Yangxiang, Meiyuan, Wuxi City, Jiangsu Province 214064, People's Republic of China.
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Improving the management of imported schistosomiasis haematobia in China: lessons from a case with multiple misdiagnoses. Parasit Vectors 2013; 6:260. [PMID: 24020375 PMCID: PMC3848274 DOI: 10.1186/1756-3305-6-260] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Accepted: 09/10/2013] [Indexed: 12/22/2022] Open
Abstract
Background Human Schistosoma haematobium infection that causes urinary schistosomiasis occurs in Africa and the eastern Mediterranean, and China is only endemic for S. japonicum. In this report, we reported an imported case with S. haematobium infection returning from Angola to Shaanxi Province, northwestern China, where S. japonicum is not endemic. Findings The case was misdiagnosed as ureteral calculus, invasive urothelial carcinoma and eosinophilic cystitis in several hospitals, and was finally diagnosed by means of serological assay followed by microscopic examination of the urine sediment. The patient was then treated with praziquantel, and a satisfactory outcome was obtained. Conclusions As S. haematobium is not indigenous to China, most Chinese doctors and medical technicians are unfamiliar with this introduced parasitic disease, therefore, they need to increase the awareness of its existence when they encounter persons who have visited or resided in endemic areas, and the techniques for detection of the parasite, so as to reduce the misdiagnosis. In addition, health education should be given to those who will go to the endemic areas to improve their knowledge and awareness on prevention and control of schistosomiasis haematobia, thereby reducing the risk of exposure to the infested freshwater.
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