Natural variables separate the endemic areas of Clonorchis sinensis and Opisthorchis viverrini along a continuous,straight zone in Southeast Asia

Background Clonorchiasis and opisthorchiasis,caused by the liver flukes Clonorchis sinensis and Opisthorchis viverrini respectively,represent significant neglected tropical diseases(NTDs)in Asia.The co-existence of these pathogens in overlapping regions complicates effective disease control strategies.This study aimed to clarify the distribution and interaction of these diseases within Southeast Asia.Methods We systematically collated occurrence records of human clonorchiasis(n=1809)and opisthorchiasis(n=731)across the Southeast Asia countries.Utilizing species distribution models incorporating environmental and climatic data,coupled machine learning algorithms with boosted regression trees,we predicted and distinguished endemic areas for each fluke species.Machine learning techniques,including geospatial analysis,were employed to delineate the boundaries between these flukes.Results Our analysis revealed that the endemic range of C.sinensis and O.viverrini in Southeast Asia primarily spans across part of China,Vietnam,Thailand,Laos,and Cambodia.During the period from 2000 to 2018,we identified C.sinensis infections in 84 distinct locations,predominantly in southern China(Guangxi Zhuang Autonomous Region)and northern Vietnam.In a stark contrast,O.viverrini was more widely distributed,with infections documented in 721 locations across Thailand,Laos,Cambodia,and Vietnam.Critical environmental determinants were quantitatively analyzed,revealing annual mean temperatures ranging between 14 and 20°C in clonorchiasis-endemic areas and 24-30°C in opisthorchiasis regions(P<0.05).The machine learning model effectively mapped a distinct demarcation zone,demonstrating a clear separation between the endemic areas of these two liver flukes with AUC from 0.9 to1.The study in Vietnam delineates the coexistence and geographical boundaries of C.sinensis and O.viverrini,revealing distinct endemic zones and a transitional area where both liver fluke species overlap.Conclusions Our findings highlight the critical role of specific climatic and environmental factors in influencing the geographical distribution of C.sinensis and O.viverrini.This spatial delineation offers valuable insights for integrated surveillance and control strategies,particularly in regions with sympatric transmission.The results underscore the need for tailored interventions,considering regional epidemiological variations.Future collaborations integrating eco-epidemiology,molecular epidemiology,and parasitology are essential to further elucidate the complex interplay of liver fluke distributions in Asia.

Synergistic integration of climate change and zoonotic diseases by artificial intelligence:a holistic approach for sustainable solutions

Artificial intelligence(AI)is a rapidly evolving field that can impel research in communicable diseases with respect to climate projections,ecological indicators and environmental impact,at the same time revealing new,previously overlooked events.A number of zoonotic and vector-borne diseases already show signs of expanding their northern geographical ranges and appropriate risk assessment and decision support are urgently needed.The deployment of AI-enabled monitoring systems tracking animal populations and environmental changes is of immense potential in the study of transmission under different climate scenarios.In addition,AI's capability to identify new treatments should not only accelerate drug and vaccine discovery but also help predicting their effectiveness,while its contribution to genetic pathogen speciation would assist the evaluation of spillover risks with regard to viral infections from animals to human.Close collaboration between AI experts,epidemiologists and other stakeholders is not only crucial for responding to challenges interconnected with a variety of variables effectively,but also necessary to warrant responsible AI use.Despite its wider successful implementation in many fields,AI should be seen as a complement to,rather than a replacement of,traditional public health measures.

Challenges and response to pandemics as seen in a One Health perspective

The global pandemic caused by the coronavirus disease 2019 not only exposed the fragility of global preparedness and response to public health emergence,but also illustrated the fragmentation and gaps of research and development ecosystem.This emphasizes the need for planned actions against the potentiality of new pandemics and requires research to better understand how viruses bridge the animal/human divide making human-to-human transmission of new diseases possible.Major challenges to response to new epidemics under the current health framework reside in the so called 4-CC approach that focuses on Concept,Communication,Coherence,and Continuity.There is a need to also add a One Health perspective with emphasis on governance,surveillance,capacity building and multi-disciplinary research to achieve a holistic and better integrated system.Using a regulatory framework to equip professionals might facilitate the function of a multi-sector approach that recognizes the value of their mandates and a One Health approach in their work.Collaborative,multisectoral actions under the global regulations and guidance would make evidence-based One Health approaches sustainable and accessible to everyone.

A One Health information database based on standard bibliometric analysis

Background:One Health is an integrated concept of health that aims to optimize the health of humans,animals,plants,and the environment.Identifying research gaps and specific expertise areas is important for understanding the role of One Health in practice.This information on One Health could be used to promote collaboration and research,inspire innovative ideas,and accelerate the translation of evidence-based practices into policies.Methods:We searched the Scopus database for publications related to One Health between 2012 and 2021 to extract bibliometric information and investigate the possibility of establishing a dedicated expertise database.We matched scholarly information using SciVal to exclude duplicate information and identify scholars’affiliations,countries,and academic profiles.Individual academic contributions to One Health were evaluated according to their citations,publication impact,publication type,and author contributions.Results:A total of 8,313 publications on One Health over a ten-year period were identified,with the number of publications increasing over time.The largest number of publications came from the United States and the United Kingdom.These countries also had the highest number of experts and a high level of international collaboration.We identified 500 scholars from 53 countries and 313 affiliations with a median Hirsch Index of 20 who could be included in a One Health expert database.These scientists had a median of six publications on One Health,with topics mostly focusing on dengue and antimicrobial resistance.Conclusion:A One Health information database could be used as a third-party reference for scholars,a source to track the ongoing academic progress,and support for active scholars in this field of research.

Corrigendum to‘A One Health information database based on standard bibliometric analysis’[Science in One Health 1(2022)100012]

Following publication of the original article[1],it was found the number of countries with identified One Health publications was incorrectly shown in Table 2,Supplementary data-Multimedia component 3(Table-S2),corresponding text and Fig.3,which should be corrected to 178.The number of countries with 500 One Health experts identified should be corrected to 53 in the abstract.

Surveillance-based evidence:elimination of schistosomiasis as a public health problem in the Peoples’Republic of China

Background:A steady progress on schistosomiasis control in the Peoples’Republic of China(P.R.China)was achieved and broadened into the twelve-year medium and long term national plan(MLNP)which marled the implementation of an integrated control strategy across all endemic areas in P.R.China in 2004.To understand the endemic trends of schistosomiasis to assess the effectiveness of an integrated strategy,we conducted an analysis of schistosomiasis surveillance data spanned from 2005 to 2015.Methods:The schistosomiasis sentinel surveillance data from sentinel sites were collected and analyzed from 2005 to 2015.In these sentinel sites,residents aged 6 years or above were screened annually by indirect hemagglutination assay(IHA),while only antibody positives were followed by stool examination either Kato-katz method(KK)and/or hatching technique(HT).Domestic animals raised in sentinel sites were examined by HT for confirming the infection of schistosomes.Snail investigation was conducted each year through systematic sampling method combined with environmental sampling method.The snails collected from field were tested by microscopic dissection method.The infection rates of schistosomes in residents,domestic animals and snails,as well as the indicators reflecting the snails’distribution were calculated and analyzed.ANOVA analysis was used to examine the changes of the number of eggs per gram feces in population and Chi-square test was used to examine any change in proportions among groups.Results:A total of 148902 residents from sentinel sites attended this study and 631676 blood samples were examined by IHA test during the 11 covered years.The annual average antibody positive rates presented a significant decrease trends,from 17.48%(95%CI:17.20–17.75%)in 2005 to 5.93%(95%CI:5.71–6.15%)(χ2=8890.47,P<0.001)in 2015.During 2005–2015,the average infection rate of schistosomes in residents declined from 2.07%(95%CI:1.96–2.17%)to 0.13%(95%CI:0.09–0.16%),accompanied by significant decrease of infection intensity in population.In 2015,the stool positives were only found in farmers,fishermen and boatmen with infection rate of 0.16%(95%CI:0.11–0.20%),0.17%(95%CI:0–0.50%)respectively.The infection rate of schistosomes in domestic animals dropped from 9.42%(538/5711,95%CI:8.66–10.18%)to 0.08%(2/2360,95%CI:0–0.20%)from 2005 to 2015.Infections were found in eight species of domestic animals at the beginning of surveillance while only two cattle were infected in 2015.Totally 98 ha of new snail habitats were found,while 94.90%(93/98)distributed in lake and marshland regions.The percentage of frames with snails decreased from 16.96%(56884/335391,95%CI:16.83–17.09%)in 2005 to 4.28%(18121/423755,95%CI:4.22–4.34%)in 2014,with a slightly increase in 2015.Meanwhile,the infection rate of schistosomes in snails was decreased from 0.26%(663/256531,95%CI:0.24–0.28%)to zero during 2005–2015.Conclusions:The infection rate of schistosomes declined significantly,providing evidence that the goal of the MLNP was achieved.Elimination of schistosomiasis as a public health problem defined as WHO was also reached in P.R.China nationwide.Surveillance-response system should be improved and strengthened to realize the final goal of schistosomiasis elimination.

Neglected tropical diseases in the People’s Republic of China: progress towards elimination

Since the founding of the People's Republic of China in 1949,considerable progress has been made in the control and elimination of the country's initial set of 11 neglected tropical diseases.Indeed,elimination as a public health problem has been declared for lymphatic filariasis in 2007 and for trachoma in 2015.The remaining numbers of people affected by soil-transmitted helminth infection,clonorchiasis,taeniasis,and echinococcosis in 2015 were 29.1 million,6.0 million,366200,and 166100,respectively.In 2017,after more than 60 years of uninterrupted,multifaceted schistosomiasis control,has seen the number of cases dwindling from more than 10 million to 37600.Meanwhile,about 6000 dengue cases are reported,while the incidence of leishmaniasis,leprosy,and rabies are down at 600 or fewer per year.Sustained social and economic development,going hand-in-hand with improvement of water,sanitation,and hygiene provide the foundation for continued progress,while rigorous surveillance and specific public health responses will consolidate achievements and shape the elimination agenda.Targets for poverty elimination and strategic plans and intervention packages post-2020 are important opportunities for further control and elimination,when remaining challenges call for sustainable efforts.

Surveillance-response systems: the key to elimination of tropical diseases

Tropical diseases remain a major cause of morbidity and mortality in developing countries.Although combined health efforts brought about significant improvements over the past 20 years,communities in resource-constrained settings lack the means of strengthening their environment in directions that would provide less favourable conditions for pathogens.Still,the impact of infectious diseases is declining worldwide along with progress made regarding responses to basic health problems and improving health services delivery to the most vulnerable populations.The London Declaration on Neglected Tropical Diseases(NTDs),initiated by the World Health Organization’s NTD roadmap,set out the path towards control and eventual elimination of several tropical diseases by 2020,providing an impetus for local and regional disease elimination programmes.Tropical diseases are often patchy and erratic,and there are differing priorities in resources-limited and endemic countries at various levels of their public health systems.In order to identify and prioritize strategic research on elimination of tropical diseases,the‘First Forum on Surveillance-Response System Leading to Tropical Diseases Elimination’was convened in Shanghai in June 2012.Current strategies and the NTD roadmap were reviewed,followed by discussions on how to identify and critically examine prevailing challenges and opportunities,including inter-sectoral collaboration and approaches for elimination of several infectious,tropical diseases.A priority research agenda within a‘One Health-One World’frame of global health was developed,including(i)the establishment of a platform for resource-sharing and effective surveillance-response systems for Asia Pacific and Africa with an initial focus on elimination of lymphatic filariasis,malaria and schistosomiasis;(ii)development of new strategies,tools and approaches,such as improved diagnostics and antimalarial therapies;(iii)rigorous validation of surveillance-response systems;and(iv)designing pilot studies to transfer Chinese experiences of successful surveillance-response systems to endemic countries with limited resources.

Surveillance and response systems for elimination of tropical diseases: summary of a thematic series in Infectious Diseases of Poverty

The peer-reviewed journal Infectious Diseases of Poverty provides a new platform to engage with,and disseminate in an open-access format,science outside traditional disciplinary boundaries.The current piece reviews a thematic series on surveillance-response systems for elimination of tropical diseases.Overall,22 contributions covering a broad array of diseases are featured–i.e.clonorchiasis,dengue,hepatitis,human immunodeficiency virus/acquired immune deficiency syndrome(HIV/AIDS),H7N9 avian influenza,lymphatic filariasis,malaria,Middle East respiratory syndrome(MERS),rabies,schistosomiasis and tuberculosis(TB).There are five scoping reviews,a commentary,a letter to the editor,an opinion piece and an editorial pertaining to the theme“Elimination of tropical disease through surveillance and response”.The remaining 13 articles are original contributions mainly covering(i)drug resistance;(ii)innovation and validation in the field of mathematical modelling;(iii)elimination of infectious diseases;and(iv)social media reports on disease outbreak notifications released by national health authorities.Analysis of the authors’affiliations reveals that scientists from the People’s Republic of China(P.R.China)are prominently represented.Possible explanations include the fact that the 2012 and 2014 international conferences pertaining to surveillance-response mechanisms were both hosted by the National Institute of Parasitic Diseases(NIPD)in Shanghai,coupled with P.R.China’s growing importance with regard to the control of infectious diseases.Within 4 to 22 months of publication,three of the 22 contributions were viewed more than 10000 times each.With sustained efforts focusing on relevant and strategic information towards control and elimination of infectious diseases,Infectious Diseases of Poverty has become a leading journal in the field of surveillance and response systems in infectious diseases and beyond.

Infestation risk of the intermediate snail host of Schistosomajaponicum in the Yangtze River Basin: improved results by spatial reassessment and a random forest approach

Background:Oncomelania hupensis is only intermediate snail host of Schistosomajaponicum,and distribution of 0.hupensis is an important indicator for the surveillance of schistosomiasis.This study explored the feasibility of a random forest algorithm weighted by spatial distance for risk prediction of schistosomiasis distribution in the Yangtze River Basin in China,with the aim to produce an improved precision reference for the national schistosomiasis control programme by reducing the number of snail survey sites without losing predictive accuracy.Methods:The snail presence and absence records were collected from Anhui,Hunan,Hubei,Jiangxi and Jiangsu provinces in 2018.A machine learning of random forest algorithm based on a set of environmental and climatic variables was developed to predict the breeding sites of the 0.hupensis intermediated snail host of S.japonicum.Different spatial sizes of a hexagonal grid system were compared to estimate the need for required snail sampling sites.The predictive accuracy related to geographic distances between snail sampling sites was estimated by calculating Kappa and the area under the curve(AUC).Results:The highest accuracy(AUC=0.889 and Kappa=0.618)was achieved at the 5 km distance weight.The five factors with the strongest correlation to 0.hupensis infestation probability were:(1)distance to lake(48.9%),(2)distance to river(36.6%),(3)isothermality(29.5%),(4)mean daily difference in temperature(28.1%),and(5)altitude(26.0%).The risk map showed that areas characterized by snail infestation were mainly located along the Yangtze River,with the highest probability in the dividing,slow-flowing river arms in the middle and lower reaches of the Yangtze River in Anhui,followed by areas near the shores of China's two main lakes,the Dongting Lake in Hunan and Hubei and the Poyang Lake in Jiangxi.Conelusions:Applying the machine learning of random forest algorithm made it feasible to precisely predict snail infestation probability,an approach that could improve the sensitivity of the Chinese schistosome surveillance.system.Redesign of the snail surveillance system by spatial bias correction of 0.hupensis infestation in the Yangtze River Basin to reduce the number of sites required to investigate from 2369 to 1747.

Elimination of schistosomiasis:the tools required

Background:Historically,the target in the schistosomiasis control has shifted from infection to morbidity,then back to infection,but now as a public health problem,before moving on to transmission control.Currently,all endemic countries are encouraged to increase control efforts and move towards elimination as required by the World Health Organization(WHO)roadmap for the global control of the neglected tropical diseases(NTDs)and the WHA65.21 resolution issued by the World Health Assembly.However,schistosomiasis prevalence is still alarmingly high and the global number of disability-adjusted life years(DALYs)due to this infection has in fact increased due to inclusion of some‘subtle’clinical symptoms not previously counted.Main body:There is a need to restart and improve efforts to reach the elimination goal.To that end,the first conference of the Global Schistosomiasis Alliance(GSA)Research Working Group was held in mid-June 2016 in Shanghai,People’s Republic of China.It reviewed current progress in schistosomiasis control and elimination,identified pressing operational research gaps that need to be addressed and discussed new tools and strategies required to make elimination a reality.The articles emanating from the lectures and discussions during this meeting,together with some additional invited papers,have been collected as a special issue of the‘Infectious Diseases of Poverty’entitled‘Schistosomiasis Research:Providing the Tools Needed for Elimination’,consisting of 26 papers in all.This paper refers to these papers and discusses critical questions arising at the conference related to elimination of schistosomiasis.Conclusion:The currently most burning questions are the following:Can schistosomiasis be eliminated?Does it require better,more highly sensitive diagnostics?What is the role of preventive chemotherapy at the elimination stage?Is praziquantel sufficient or do we need new drugs?Contemplating these questions,it is felt that the heterogeneity of the endemic areas in the world requires WHO policies to be upgraded instituting new,differentiated guidelines.

Nobel prize for the artemisinin and ivermectin discoveries: a great boost towards elimination of the global infectious diseases of poverty

The Millennium Development Goals(MDGs)made a marked transformation for neglected and vulnerable communities in the developing countries from the start,but infectious diseases of poverty(IDoPs)continue to inflict a disproportionate global public health burden with associated consequences,thereby contributing to the vicious cycle of poverty and inequity.However,the effectiveness and large-scale coverage of artemisinin combination therapy(ACT)have revolutionized malaria treatment just as the control of lymphatic filariasis(LF)and onchocerciasis have benefitted from harnessing the broad-spectrum effect of avermectin-based derivatives.The paradigm shift in therapeutic approach,effected by these two drugs and their impact on community-based interventions of parasitic diseases plaguing the endemic low-and middle-income countries(LIMCs),led to the Nobel Prize in Physiology or Medicine in 2015.However,the story would not be complete without mentioning praziquantel.The huge contribution of this drug in modernizing the control of schistosomiasis and also some intestinal helminth infections had already shifted the focus from control to potential elimination of this disease.Together,these new drugs have provided humankind with powerful new tools for the alleviation of infectious diseases that humans have lived with since time immemorial.These drugs all have broad-spectrum effects,yet they are very safe and can even be packaged together in various combinations.The strong effect on so many of the great infectious scourges in the developing countries has not only had a remarkable influence on many endemic diseases,but also contributed to improving the cost structure of healthcare.Significant benefits include improved quality of preventive and curative medicine,promotion of community-based interventions,universal health coverage and the fostering of global partnerships.The laudable progress and benefits achieved are indispensable in championing,strengthening and moving forward elimination of the IDoPs.However,there is an urgent need for further innovative,contextual and integrated approaches along with the advent of the Sustainable Development Goals(SDGs),replacing the MDGs in ensuring global health security,well-being and economic prosperity for all.

Controlling schistosomiasis with praziquantel:How much longer without a viable alternative?

The current approach of morbidity control of schistosomiasis,a helminth disease of poverty with considerable public health and socioeconomic impact,is based on preventive chemotherapy with praziquantel.There is a pressing need for new drugs against this disease whose control entirely depends on this single drug that has been widely used over the past 40 years.We argue that a broader anthelminthic approach supplementing praziquantel with new antischistosomals targeting different parasite development stages would not only increase efficacy but also reduce the risk for drug resistance.Repositioning drugs already approved for other diseases provides a shortcut to clinical trials,as it is expected that such drugs rapidly pass the regulatory authorities.The antischistosomal properties of antimalarial drugs(e.g.,semisynthetic artemisinins,synthetic trioxolanes,trioxaquines and mefloquine)and of drugs being developed or registered for other purposes(e.g.,moxidectin and miltefosin),administered alone or in combination with praziquantel,have been tested in the laboratory and clinical trials.Another avenue to follow is the continued search for new antischistosomal properties in plants.Here,we summarise recent progress made in schistosomiasis chemotherapy,placing particular emphasis on repositioning of existing drugs against schistosomiasis.

Control of neglected tropical diseases in Asia Pacific: implications for health information priorities

Poverty magnifies limitations posed by traditional biases and environmental risks.Any approach towards disease control needs to recognise that socially embedded vulnerabilities can be as powerful as externally imposed infections.Asia Pacific has a specific panorama of infectious diseases,which,in common with other endemic areas,have a tendency to emerge or re-emerge if not carefully monitored.Sustained control aiming at elimination requires strong emphasis on surveillance and response.Well-designed informatics platforms can improve support systems and strengthen control activities,as they rapidly locate high-risk areas and provide detailed,up-to-date information on the performance of ongoing control programmes.

Space-time clustering and associated risk factors of pulmonary tuberculosis in southwest China

Background:Pulmonary tuberculosis(PTB,both smear positive and smear negative)is an airborne infectious disease of major public health concern in China and other parts of the world where PTB endemicity is reported.This study aims at identifying PTB spatio-temporal clusters and associated risk factors in Zhaotong prefecture-level city,located in southwest China,where the PTB notification rate was higher than the average rate in the entire country.Methods:Space-time scan statistics were carried out using PTB registered data in the nationwide TB online registration system from 2011 to 2015,to identify spatial clusters.PTB patients diagnosed between October 2015 and February 2016 were selected and a structured questionnaire was administered to collect a set of variables that includes socio-economic status,behavioural characteristics,local environmental and biological characteristics.Based on the discovery of detailed town-level spatio-temporal PTB clusters,we divided selected subjects into two groups including the cases that resides within and outside identified clusters.Then,logistic regression analysis was applied comparing the results of variables between the two groups.Results:A total of 1508 subjects consented and participated in the survey.Clusters for PTB cases were identified in 38 towns distributed over south-western Zhaotong.Logistic regression analysis showed that history of chronic bronchitis(OR=3.683,95%CI:2.180-6.223),living in an urban area(OR=5.876,95%CI:2.381-14.502)and using coal as the main fuel(OR=9.356,95%CI:5.620-15.576)were independently associated with clustering.While,not smoking(OR=0.340,95%CI:0.137-0.843)is the protection factor of spatial clustering.Conclusions:We found PTB specially clustered in south-western Zhaotong.The strong associated factors influencing the PTB spatial cluster including:the history of chronic bronchitis,living in the urban area,smoking and the use of coal as the main fuel for cooking and heating.Therefore,efforts should be made to curtail these associated factors.

The pathology,phylogeny,and epidemiology of Echinococcus ortleppi(G5 genotype):a new case report of echinococcosis in China

Background:Cystic echinococcosis(CE),caused by the larval stage of the complex Echinococcus granulosus sensu lato(s.l.),is a zoonotic parasitic disease with a high social burden in China.E.ortleppi is a species(formerly genotype 5 of E.granulosus s.l.)with unique epidemic areas(tropical areas),transmission patterns(mainly cattle origin),and pathological characteristics(large and small hook lengths)compared to other species that cause CE.A 19-year-old female patient in an area with no history of echinococcosis in Guizhou Province,China,was diagnosed with E.ortleppi infection in 2019.This study is to understand the source of this human E.ortleppi infection.Methods:We performed computer tomography(CT)scans,surgical operation,morphological sectioning,molecular diagnosis,phylogenetic analyses,and epidemiological investigation in Anshun City,Guizhou Province,China in 2019.Results:The patient presented with intermittent distension and pain in the upper abdomen without other abnormal symptoms.Routine blood examination results were normal.However,abdominal CT revealed a fertile cyst with a diameter of approximately 8 cm,uniform density,and a clear boundary,but without an evident cyst wall in the right lobe of the liver.The cyst was fertile,and phylogenetic analyses revealed that the isolates represented a new E.ortleppi genus haplotype.A result of 10‒14 years incubation period with indigenous infection was considered available for the case through the epidemiological survey.Conclusions:CE due to E.ortleppi infection can be confused with other diseases causing liver cysts,resulting in misdiagnosis.A transmission chain of E.ortleppi may exist or existed in the past in the previously considered nonendemic areas of echinococcosis in southwestern China.

Comparison of novel and standard diagnostic tools for the detection of Schistosoma mekongi infection in Lao People’s Democratic Republic and Cambodia

Background:Given the restricted distribution of Schistosoma mekongi in one province in Lao People’s Democratic Republic(Lao PDR)and two provinces in Cambodia,together with progress of the national control programmes aimed at reducing morbidity and infection prevalence,the elimination of schistosomiasis mekongi seems feasible.However,sensitive diagnostic tools will be required to determine whether elimination has been achieved.We compared several standard and novel diagnostic tools in S.mekongi-endemic areas.Methods:The prevalence and infection intensity of S.mekongi were evaluated in 377 study participants from four villages in the endemic areas in Lao PDR and Cambodia using Kato-Katz stool examination,antibody detection based on an enzyme-linked immunosorbent assay(ELISA)and schistosome circulating antigen detection by lateral-flow tests.Two highly sensitive test systems for the detection of cathodic and anodic circulating antigens(CCA,CAA)in urine and serum were utilized.Results:Stool microscopy revealed an overall prevalence of S.mekongi of 6.4%(one case in Cambodia and 23 cases in Lao PDR),while that of Opisthorchis viverrini,hookworm,Trichuris trichiura,Ascaris lumbricoides and Taenia spp.were 50.4%,28.1%,3.5%,0.3%and 1.9%,respectively.In the urine samples,the tests for CCA and CAA detected S.mekongi infections in 21.0%and 38.7%of the study participants,respectively.In the serum samples,the CAA assay revealed a prevalence of 32.4%,while a combination of the CAA assay in serum and in urine revealed a prevalence of 43.2%.There was a difference between the two study locations with a higher prevalence reached in the samples from Lao PDR.Conclusions:The CCA,CAA and ELISA results showed substantially higher prevalence estimates for S.mekongi compared to Kato-Katz thick smears.Active schistosomiasis mekongi in Lao PDR and Cambodia might thus have been considerably underestimated previously.Hence,sustained control efforts are still needed to break transmission of S.mekongi.The pivotal role of highly sensitive diagnostic assays in areas targeting elimination cannot be overemphasised.

Infuence of urbanization on schistosomiasis infection risk in Anhui Province based on sixteen year’s longitudinal surveillance data:a spatio-temporal modelling study

Background Urbanization greatly afects the natural and social environment of human existence and may have a multifactoral impact on parasitic diseases.Schistosomiasis,a common parasitic disease transmitted by the snail Oncomelania hupensis,is mainly found in areas with population aggregations along rivers and lakes where snails live.Previous studies have suggested that factors related to urbanization may infuence the infection risk of schistosomiasis,but this association remains unclear.This study aimed to analyse the efect of urbanization on schistosomiasis infection risk from a spatial and temporal perspective in the endemic areas along the Yangtze River Basin in China.Methods County-level schistosomiasis surveillance data and natural environmental factor data covering the whole Anhui Province were collected.The urbanization level was characterized based on night-time light data from the Defense Meteorological Satellite Program Operational Linescan System(DMSP-OLS)and the National Polar-Orbiting Partnership’s Visible Infrared Imaging Radiometer Suite(NPP-VIIRS).The geographically and temporally weighted regression model(GTWR)was used to quantify the infuence of urbanization on schistosomiasis infection risk with the other potential risk factors controlled.The regression coefcient of urbanization was tested for signifcance(α=0.05),and the infuence of urbanization on schistosomiasis infection risk was analysed over time and across space based on signifcant regression coefcients.Variables studied included climate,soil,vegetation,hydrology and topography.Results The mean regression coefcient for urbanization(0.167)is second only to the leached soil area(0.300),which shows that the urbanization is the most important infuence factors for schistosomiasis infection risk besides leached soil area.The other important variables are distance to the nearest water source(0.165),mean minimum temperature(0.130),broadleaf forest area(0.105),amount of precipitation(0.073),surface temperature(0.066),soil bulk density(0.037)and grassland area(0.031).The infuence of urbanization on schistosomiasis infection risk showed a decreasing trend year by year.During the study period,the signifcant coefcient of urbanization level increased from−0.205 to−0.131.Conclusions The infuence of urbanization on schistosomiasis infection has spatio-temporal heterogeneous.The urbanization does reduce the risk of schistosomiasis infection to some extend,but the strength of this infuence decreases with increasing urbanization.Additionally,the efect of urbanization on schistosomiasis infection risk was greater than previous reported natural environmental factors.This study provides scientifc basis for understanding the infuence of urbanization on schistosomiasis,and also provides the feasible research methods for other similar studies to answer the issue about the impact of urbanization on disease risk.

Pattern analysis of schistosomiasis prevalence by exploring predictive modeling in Jiangling County,Hubei Province,P.R.China

Background:The prevalence of schistosomiasis remains a key public health issue in China.Jiangling County in Hubei Province is a typical lake and marshland endemic area.The pattern analysis of schistosomiasis prevalence in Jiangling County is of significant importance for promoting schistosomiasis surveillance and control in the similar endemic areas.Methods:The dataset was constructed based on the annual schistosomiasis surveillance as well the socio-economic data in Jiangling County covering the years from 2009 to 2013.A village clustering method modified from the K-mean algorithm was used to identify different types of endemic villages.For these identified village clusters,a matrix-based predictive model was developed by means of exploring the one-step backward temporal correlation inference algorithm aiming to estimate the predicative correlations of schistosomiasis prevalence among different years.Field sampling of faeces from domestic animals,as an indicator of potential schistosomiasis prevalence,was carried out and the results were used to validate the results of proposed models and methods.Results:The prevalence of schistosomiasis in Jiangling County declined year by year.The total of 198 endemic villages in Jiangling County can be divided into four clusters with reference to the 5 years’occurrences of schistosomiasis in human,cattle and snail populations.For each identified village cluster,a predictive matrix was generated to characterize the relationships of schistosomiasis prevalence with the historic infection level as well as their associated impact factors.Furthermore,the results of sampling faeces from the front field agreed with the results of the identified clusters of endemic villages.Conclusion:The results of village clusters and the predictive matrix can be regard as the basis to conduct targeted measures for schistosomiasis surveillance and control.Furthermore,the proposed models and methods can be modified to investigate the schistosomiasis prevalence in other regions as well as be used for investigating other parasitic diseases.

High-risk spatiotemporal patterns of cutaneous leishmaniasis:a nationwide study in Iran from 2011 to 2020

Background Cutaneous leishmaniasis(CL)is a wide-reaching infection of major public health concern.Iran is one of the six most endemic countries in the world.This study aims to provide a spatiotemporal visualization of CL cases in Iran at the county level from 2011 to 2020,detecting high-risk zones,while also noting the movement of high-risk clusters.Methods On the basis of clinical observations and parasitological tests,data of 154,378 diagnosed patients were obtained from the Iran Ministry of Health and Medical Education.Utilizing spatial scan statistics,we investigated the disease’s purely temporal,purely spatial,spatial variation in temporal trends and spatiotemporal patterns.At P=0.05 level,the null hypothesis was rejected in every instance.Results In general,the number of new CL cases decreased over the course of the 9-year research period.From 2011 to 2020,a regular seasonal pattern,with peaks in the fall and troughs in the spring,was found.The period of September–February of 2014–2015 was found to hold the highest risk in terms of CL incidence rate in the whole country[relative risk(RR)=2.24,P<0.001)].In terms of location,six signifcant high-risk CL clusters covering 40.6%of the total area of the country were observed,with the RR ranging from 1.87 to 9.69.In addition,spatial variation in the temporal trend analysis found 11 clusters as potential high-risk areas that highlighted certain regions with an increasing tendency.Finally,fve space-time clusters were found.The geographical displacement and spread of the disease followed a moving pattern over the 9-year study period afecting many regions of the country.Conclusions Our study has revealed signifcant regional,temporal,and spatiotemporal patterns of CL distribution in Iran.Over the years,there have been multiple shifts in spatiotemporal clusters,encompassing many diferent parts of the country from 2011 to 2020.The results reveal the formation of clusters across counties that cover certain parts of provinces,indicating the importance of conducting spatiotemporal analyses at the county level for studies that encompass entire countries.Such analyses,at a fner geographical scale,such as county level,might provide more precise results than analyses at the scale of the province.