蒿甲醚对感染小鼠体内埃及血吸虫皮层的损害(英文)

目的评价蒿甲醚对小鼠体内埃及血吸虫皮层的损害作用。方法8只小鼠于感染埃及血吸虫尾蚴后81d,用单剂蒿甲醚400mg/kg口服治疗。治疗后1、3、7和14d各剖杀2只小鼠,用灌注法收集血吸虫,并按常规方法固定和处置虫体,作扫描电镜观察。从另2只未作治疗的感染小鼠取虫作对照。结果用蒿甲醚治疗后24h,雄虫的皮层结节肿大、破溃或从皮层上剥落;在雄虫和雌虫的体表可查见有局灶性或广泛的皮层肿胀、融合、空泡变化、糜烂和剥落,以及感觉结构的破坏。治疗后3d,雌、雄虫的皮层损害加重,最严重的损害为口吸盘肿胀和破溃,并查见皮层褶嵴有广泛和严重的肿胀、糜烂和剥落,以及雌虫盘状感觉结构的破坏。治疗后7至14d,有些虫仍示有中或重度皮层损害,而有些仍存活的虫则示其大部分皮层已有明显恢复。结论蒿甲醚对埃及血吸虫的皮层具有广泛和严重的损害作用。

蒿甲醚对感染小鼠体内埃及血吸虫超微结构的影响

目的观察蒿甲醚对小鼠体内埃及血吸虫成虫超微结构的损害。方法8只小鼠于感染埃及血吸虫尾蚴后81d用单剂蒿甲醚400mg/kg口服治疗。治后24h、3d、7d和14d各剖杀2只小鼠,用灌注法收集血吸虫,并按常规方法固定和处置虫体,作透射电镜观察。从另2只未治疗的感染小鼠体内取虫作对照。结果蒿甲醚对血吸虫皮层超微结构的损害主要是皮层基质的肿胀、溶解和空泡变化,基底膜消失和部份受损皮层破裂;在感觉器和皮层结节中,常见其内部结构广泛溶解。在肌层、实质组织、合体细胞和肠管上皮细胞中,查见局灶性或广泛的溶解、粗面内质网减少及线粒体空泡变化和变性。雌虫卵黄细胞的严重变化是空泡变化、粗面内质网减少、卵黄球融合以及受损卵黄细胞破溃等。上述雌、雄虫变化于感染小鼠用蒿甲醚治疗后24h即可见到,并逐渐加重,3～7d后最重。治后14d,部分雌、雄虫仍示有超微结构的损害,但同时亦观察到受损虫组织的恢复。结论蒿甲醚对埃及血吸虫成虫的皮层和皮层下组织具有广泛和严重的超微结构损害。

Environmental determinants of access to shared sanitation in informal settlements:a cross-sectional study in Abidjan and Nairobi

Background Universal access to basic sanitation remains a global challenge,particularly in low-and middle-income countries.Efforts are underway to improve access to sanitation in informal settlements,often through shared facilities.However,access to these facilities and their potential health gains—notably,the prevention of diarrheal diseases—may be hampered by contextual aspects related to the physical environment.This study explored associations between the built environment and perceived safety to access toilets,and associations between the latter and diarrheal infections.Methods A cross-sectional study was carried out between July 2021 and February 2022,including 1714 households in two informal settlements in Abidjan(Côte d’Ivoire)and two in Nairobi(Kenya).We employed adjusted odds ratios(aORs)obtained from multiple logistic regressions(MLRs)to test whether the location of the most frequently used toilet was associated with a perceived lack of safety to use the facility at any time,and whether this perceived insecurity was associated with a higher risk of diarrhea.The MLRs included several exposure and control variables,being stratified by city and age groups.We employed bivariate logistic regressions to test whether the perceived insecurity was associated with settlement morphology indicators derived from the built environment.Results Using a toilet outside the premises was associated with a perceived insecurity both in Abidjan[aOR=3.14,95%confidence interval(CI):1.13–8.70]and in Nairobi(aOR=57.97,95%CI:35.93–93.53).Perceived insecurity to access toilets was associated with diarrheal infections in the general population(aOR=1.90,95%CI:1.29–2.79 in Abidjan,aOR=1.69,95%CI:1.22–2.34 in Nairobi),but not in children below the age of 5 years.Several settlement morphology features were associated with perceived insecurity,namely,buildings’compactness,the proportion of occupied land,and angular deviation between neighboring structures.Conclusions Toilet location was a critical determinant of perceived security,and hence,must be adequately addressed when building new facilities.The sole availability of facilities may be insufficient to prevent diarrheal infections.People must also be safe to use them.Further attention should be directed toward how the built environment affects safety.

Experience and lessons from health impact assessment guiding prevention and control of HIV/AIDS in a copper mine project,northwestern Zambia

Background:To avoid or mitigate potential project-related adverse health effects,the Trident copper project in Kalumbila,northwestern Zambia,commissioned a health impact assessment.HIV was identified a priority health issue based on the local vulnerability to HIV transmission and experience from other mining projects in Africa.Hence,an HIV/AIDS management plan was developed,including community and workplace interventions,with HIV testing and counselling(HTC)being one of the key components.We present trends in HTC data over a 4-year period.Methods:In 13 communities affected by the Trident project,HTC was implemented from 2012 onwards,using rapid diagnostic tests,accompanied by pre-and post-test counselling through trained personnel.In addition,HTC was initiated in the project workforce in 2013,coinciding with the launch of the mine development.HTC uptake and HIV positivity rates were assessed in the study population and linked to demographic factors using regression analysis.Results:In total,11,638 community members and 5564 workers have taken up HTC with an increase over time.The HIV positivity rate in the community was 3.0%in 2012 and 3.4%in 2015,while positivity rate in the workforce was 5.2%in 2013 and 4.3%in 2015.Females showed a significantly higher odds of having a positive test result than males(odds ratio(OR)=1.96,95%confidence interval(CI):1.55-2.50 among women in the community and OR=2.90,95%CI:1.74-4.84 among women in the workforce).HTC users in the 35-49 years age group were most affected by HIV,with an average positivity rate of 6.6%in the community sample and 7.9%in the workforce sample.These study groups had 4.50 and 4.95 higher odds of being positive,respectively,compared to their younger counterparts(15-24 years).Conclusions:While HTC uptake increased five-fold in the community and almost three-fold in the workplace,the HIV positivity rates were insignificantly higher in 2015 compared to 2012.Our data can be used alongside other surveillance data to track HIV transmission in this specific context.Guided by the health impact assessment,the HIV prevention and control programme was readily adapted to the current setting through the identification of socioeconomic and environmental determinants of health.

Prevalence of fever of unidentifed aetiology in East African adolescents and adults: a systematic review and meta-analysis

Background Primary health care settings and hospitals of low-and middle-income countries have few accessible diagnostic tools and limited laboratory and human resources capacity to identify multiple pathogens with high accu‑racy.In addition,there is a paucity of information on fever and its underlying aetiology in the adolescent and adult population in East Africa.The purpose of this study was to estimate the pooled prevalence of fever of unidentifed aetiology among adolescent and adult febrile patients seeking health care in East Africa.Methods We pursued a systematic review using readily available electronic databases(i.e.PubMed,Cumulative Index to Nursing&Allied Health Literature,Scopus,Cochrane Library and Web of Science)without language restric‑tion from inception date of the respective databases to October 31,2022.We adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Identifed studies were screened for relevance.Further analyses based on pre-set eligibility criteria were carried out for fnal inclusion.Two reviewers independently screened and extracted data.Risk of study bias was assessed.Meta-analysis of the prevalence of fever of unidentifed aetiology was performed.Results We identifed 14,029 articles of which 25 were eligible for inclusion,reporting data from 8538 participants.The pooled prevalence of febrile cases with unidentifed aetiology was 64%[95%confdence interval(CI):51–77%,I 2=99.6%]among febrile adolescents and adults in East Africa.For the proportion of patients with identifed aetiol‑ogy,the studies documented bacterial pathogens(human bloodstream infections),bacterial zoonotic pathogens and arboviruses as the main non-malarial causative agents in East Africa.Conclusions Our study provides evidence that almost two-thirds of adolescent and adult febrile patients attending health care facilities in East Africa might receive inappropriate treatments due to unidentifed potential life-threat‑ening fever aetiology.Hence,we call for a comprehensive fever syndromic surveillance to broaden a consequential diferential diagnosis of syndromic fever and to considerably improve the course of patients’disease and treatment outcomes.

One Health as a potential platform to rescue the neglected fruit trees in Yucatan,Mexico

Neglected and underutilized species of plants(NUS)have been identified by the Food and Agriculture Organization as valuable resources for fighting poverty,hunger and malnutrition as they can help make agricultural production systems more sustainable and resilient.Adaptation of NUS to changing environments over several millennia has rendered most of these plants resistant to pests and climate change.In this paper,we explore the potential values of some of the Mayan fruit trees justifying conservation efforts in their native habitats.Our research was primarily based on a scoping review using Google Scholar.We considered articles published in English,Spanish and Portuguese.Our review rendered two sets of articles including those focusing on the nutritional and medicinal properties of NUS and their products,and those focusing on their uses in traditional medicine.Both sets of papers strongly support arguments for conservation of NUS.Additionally,our scoping review expands and includes a case study on the conservation of NUS,highlighting the critical role of civil society on how it can spearhead rescue efforts of botanical resources through the creation of what is possibly the first arboretum of its kind in the Americas.Among the project's key selling points was not only the rescue of an important component of Yucatan's cultural heritage but its nutritional value as well as its potential medicinal properties.Our paper is not prescriptive on how to preserve or even commercially exploit NUS.It is intended as a thought-provoking piece on the potential of a One Health approach as a multi-sectoral platform to support conservation efforts,while stimulating greater interest in the subject and encouraging more action from the academic and pharmaceutical sectors as well as civil society.

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.

Towards a global One Health index: a potential assessment tool for One Health performance

Background:A One Health approach has been increasingly mainstreamed by the international community, as it provides for holistic thinking in recognizing the close links and inter-dependence of the health of humans, animals and the environment. However, the dearth of real-world evidence has hampered application of a One Health approach in shaping policies and practice. This study proposes the development of a potential evaluation tool for One Health performance, in order to contribute to the scientific measurement of One Health approach and the identification of gaps where One Health capacity building is most urgently needed.Methods:We describe five steps towards a global One Health index (GOHI), including (i) framework formulation;(ii) indicator selection;(iii) database building;(iv) weight determination;and (v) GOHI scores calculation. A cell-like framework for GOHI is proposed, which comprises an external drivers index (EDI), an intrinsic drivers index (IDI) and a core drivers index (CDI). We construct the indicator scheme for GOHI based on this framework after multiple rounds of panel discussions with our expert advisory committee. A fuzzy analytical hierarchy process is adopted to determine the weights for each of the indicators.Results:The weighted indicator scheme of GOHI comprises three first-level indicators, 13 second-level indicators, and 57 third-level indicators. According to the pilot analysis based on the data from more than 200 countries/territories the GOHI scores overall are far from ideal (the highest score of 65.0 out of a maximum score of 100), and we found considerable variations among different countries/territories (31.8–65.0). The results from the pilot analysis are consistent with the results from a literature review, which suggests that a GOHI as a potential tool for the assessment of One Health performance might be feasible.Conclusions:GOHI—subject to rigorous validation—would represent the world’s first evaluation tool that constructs the conceptual framework from a holistic perspective of One Health. Future application of GOHI might promote a common understanding of a strong One Health approach and provide reference for promoting effective measures to strengthen One Health capacity building. With further adaptations under various scenarios, GOHI, along with its technical protocols and databases, will be updated regularly to address current technical limitations, and capture new knowledge.

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.

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.

Towards integrated surveillance-response systems for the prevention of future pandemics

Most human pathogens originate from non-human hosts and certain pathogens persist in animal reservoirs.The transmission of such pathogens to humans may lead to self-sustaining chains of transmission.These pathogens represent the highest risk for future pandemics.For their prevention,the transmission over the species barrier—although rare—should,by all means,be avoided.In the current COVID-19 pandemic,surprisingly though,most of the current research concentrates on the control by drugs and vaccines,while comparatively little scientific inquiry focuses on future prevention.Already in 2012,the World Bank recommended to engage in a systemic One Health approach for zoonoses control,considering integrated surveillance-response and control of human and animal diseases for primarily economic reasons.First examples,like integrated West Nile virus surveillance in mosquitos,wild birds,horses and humans in Italy show evidence of financial savings from a closer cooperation of human and animal health sectors.Provided a zoonotic origin can be ascertained for the COVID-19 pandemic,integrated wildlife,domestic animal and humans disease surveillance-response may contribute to prevent future outbreaks.In conclusion,the earlier a zoonotic pathogen can be detected in the environment,in wildlife or in domestic animals;and the better human,animal and environmental surveillance communicate with each other to prevent an outbreak,the lower are the cumulative costs.

Dynamics of freshwater snails and Schistosoma infection prevalence in schoolchildren during the construction and operation of a multipurpose dam in central Côte d’Ivoire

Background:The construction and operation of small multipurpose dams in Africa have a history of altering the transmission of water-based diseases,including schistosomiasis.The current study was designed to investigate the abundance and dynamics of schistosomiasis intermediate host snails and Schistosoma infections in humans during the construction and the first years of operation of a small multipurpose dam in Côte d’Ivoire.Methods:The study was carried out in Raffierkro and four neighbouring villages in central Côte d’Ivoire between 2007 and 2012.Snails were collected by two experienced investigators using scoops and forceps for 15 min at each site.Snails were identified at genera and,whenever possible,species level,and subjected to testing for cercarial shedding.Schoolchildren aged 6-15 years were examined once every year for Schistosoma haematobium and S.mansoni infection,using urine filtration and duplication Kato-Katz thick smears,respectively.Additionally,551 adults were examined for Schistosoma infection before(June 2007)and 359 individuals 2 years after dam construction(June 2009).Results:Overall,1700 snails belonging to nine different genera were collected from 19 sampling sites.Bulinus(potential intermediate host snails of S.haematobium)and Pila were the most common genera,whereas Biomphalaria(potential intermediate host snail of S.mansoni),Lymnaea,Physa and Melanoides were found in two villages.During the first-year sampling period,65 snails were collected,of which 13(20%)were schistosomiasis intermediate hosts.In subsequent years,out of 1635 snails collected,1079(66%)were identified as potential intermediate host for schistosomiasis,but none were shedding cercariae.The prevalence of S.mansoni among adults in the study area was low(0.4%in 2007 and 0.3%in 2009),whereas the prevalence of S.haematobium declined from 13.9%to 2.9%in this two-year period.Conclusions:The low prevalence of schistosomiasis in humans and the absence of infected intermediate host snails during the construction and early phase of operation of a small multipurpose dam suggest that there was no or only very little local transmission.However,the considerable increase in the number of intermediate host snails and their dispersion in irrigation canals call for rigorous surveillance,so that adequate public health measures can be taken in case of early signs of an outbreak.

Assessing stool quantities generated by three specific Kato-Katz thick smear templates employed in different settings

Background:The Kato-Katz technique is recommended for the diagnosis of helminth infections in epidemiological surveys,drug efficacy studies and monitoring of control interventions.We assessed the comparability of the average amount of faeces generated by three Kato-Katz templates included in test kits from two different providers.Methods:Nine hundred Kato-Katz thick smear preparations were done;300 per kit.Empty slides,slides plus Kato-Katz template filled with stool and slides plus stool after careful removal of the template were weighed to the nearest 0.1 mg.The average amount of stool that was generated on the slide was calculated for each template,stratified by standard categories of stool consistency(i.e.mushy,soft,sausage-shaped,hard and clumpy).Results:The average amount of stool generated on slides was 40.7 mg(95%confidence interval(CI):40.0–41.4 mg),40.3 mg(95%CI:39.7–40.9 mg)and 42.8 mg(95%CI:42.2–43.3 mg)for the standard Vestergaard Frandsen template,and two different templates from the Chinese Center for Disease Control and Prevention(China CDC),respectively.Mushy stool resulted in considerably lower average weights when the Vestergaard Frandsen(37.0 mg;95%CI:34.9–39.0 mg)or new China CDC templates(37.4 mg;95%CI:35.9–38.9 mg)were used,compared to the old China CDC template(42.2 mg;95%CI:40.7–43.7 mg)and compared to other stool consistency categories.Conclusion:The average amount of stool generated by three specific Kato-Katz templates was similar(40.3–42.8 mg).Since the multiplication factor is somewhat arbitrary and small changes only have little effect on infection intensity categories,it is suggested that the standard multiplication factor of 24 should be kept for the calculation of eggs per gram of faeces for all investigated templates.

Prevalence of Schistosoma mono- and co-infections with multiple common parasites and associated risk factors and morbidity profile among adults in the Taabo health and demographic surveillance system, South-Central Côte d’Ivoire

Background Schistosomiasis remains an important public health problem,also among adults,and infected individuals not treated serve as a reservoir for continued transmission.Despite this fact,evidence on the epidemiology of schistosomiasis in adults in Côte d’Ivoire is scanty.This study aimed to determine the prevalence and risk factors of Schistosoma infection and co-infection with other helminth species and Plasmodium among adults in the Taabo region in the south-central part of Côte d’Ivoire.Methods A cross-sectional survey was carried out in April and May 2017 in the frame of the“Côte d’Ivoire Dual Burden of Disease Study”(CoDuBu).A total of 901 randomly selected individuals,aged 18–90 years,provided blood,stool and urine samples for the diagnosis of malaria and helminth infections.Stool samples were subjected to the Kato-Katz technique for detection of Schistosoma mansoni and soil-transmitted helminth eggs,while urine samples were examined for eggs of Schistosoma haematobium and circulating cathodic antigen of S.mansoni.Risk factors and morbidity profiles were assessed using health examination and questionnaires.Multinomial logistic regressions were employed to identify risk factors and morbidity patterns associated with S.mansoni mono-and co-infections.Results The prevalence of S.mansoni and S.haematobium was 23.2%and 1.0%,respectively.Most S.mansoni were mono-infections(81.3%).Independent determinants of S.mansoni infection were young age,low socioeconomic status(mono-and co-infection)and poor hygiene practices(co-infection)(P<0.05).S.mansoni infection was independently associated with higher pain and symptom scores(mono-infection),poor self-rated health and low healthcare use(co-infection)(P<0.05).Conclusions This study showed that adults represent a substantial reservoir of S.mansoni.To sustain schistosomiasis control and improve people’s wellbeing,it is important to expand preventive chemotherapy from school-aged children to adults,coupled with hygiene and health education.

The economic impact of schistosomiasis

Background:The economic impact of schistosomiasis and the underlying tradeofs between water resources devel‑opment and public health concerns have yet to be quantifed.Schistosomiasis exerts large health,social and fnan‑cial burdens on infected individuals and households.While irrigation schemes are one of the most important policy responses designed to reduce poverty,particularly in sub-Saharan Africa,they facilitate the propagation of schistoso‑miasis and other diseases.Methods:We estimate the economic impact of schistosomiasis in Burkina Faso via its efect on agricultural produc‑tion.We create an original dataset that combines detailed household and agricultural surveys with high-resolution geo-statistical disease maps.We develop new methods that use the densities of the intermediate host snails of schis‑tosomiasis as instrumental variables together with panel,spatial and machine learning techniques.Results:We estimate that the elimination of schistosomiasis in Burkina Faso would increase average crop yields by around 7%,rising to 32%for high infection clusters.Keeping schistosomiasis unchecked,in turn,would correspond to a loss of gross domestic product of approximately 0.8%.We identify the disease burden as a shock to the agricultural productivity of farmers.The poorest households engaged in subsistence agriculture bear a far heavier disease burden than their wealthier counterparts,experiencing an average yield loss due to schistosomiasis of between 32 and 45%.We show that the returns to water resources development are substantially reduced once its health efects are taken into account:villages in proximity of large-scale dams sufer an average yield loss of around 20%,and this burden decreases as distance between dams and villages increases.Conclusions:This study provides a rigorous estimation of how schistosomiasis afects agricultural production and how it is both a driver and a consequence of poverty.It further quantifes the tradeof between the economics of water infrastructures and their impact on public health.Although we focus on Burkina Faso,our approach can be applied to any country in which schistosomiasis is endemic.

Strategies supporting the prevention and control of neglected tropical diseases during and beyond the COVID-19 pandemic

Emerging and re-emerging zoonotic diseases represent a public health challenge of international concern.They include a large group of neglected tropical diseases(NTDs),many of which are of zoonotic nature.Coronavirus disease 201g(COVID-19),another emerging zoonotic disease,has just increased the stakes exponentially.Most NTDs are subject to the impact of some of the very same human-related activities triggering other emerging and re-emerging diseases,including COVID-19,severe acute respiratory syndrome(SARS),bird flu and swine flu.It is conceivable that COVID-19 will exacerbate the NTDs,as it will divert much needed financial and human resources.There is considerable concern that recent progress achieved with control and elimination efforts will be reverted.Future potential strategies will need to reconsider the determinants of health in NTDs in order to galvanize efforts and come up with a comprehensive,well defined programme that will set the stage for an effective multi-sectorial approach.In this Commentary,we propose areas of potential synergies between the COVID-19 pandemic control efforts other health and non-health sector initiatives and NTD control and elimination programmes.

Prevalence and risk factors of undernutrition among schoolchildren in the Plateau Central and Centre-Ouest regions of Burkina Faso

Background:Multiple factors determine children’s nutritional status,including energy and nutrient intake,recurrent infectious diseases,access(or lack thereof)to clean water and improved sanitation,and hygiene practices,among others.The“Vegetables go to School:improving nutrition through agricultural diversification”(VgtS)project implements an integrated school garden programme in five countries,including Burkina Faso.The aim of this study was to determine the prevalence of undernutrition and its risk factors among schoolchildren in Burkina Faso before the start of the project.Methods:In February 2015,a cross-sectional survey was carried out among 455 randomly selected children,aged 8-14 years,in eight schools in the Plateau Central and Centre-Ouest regions of Burkina Faso.Nutritional status was determined by anthropometric assessment.Helminth and intestinal protozoa infections were assessed using the Kato-Katz and a formalin-ether concentration method.A urine filtration technique was used to identify Schistosoma haematobium eggs.Prevalence of anaemia was determined by measuring haemoglobin levels in finger-prick blood samples.Questionnaires were administered to children to determine their knowledge of nutrition and health and their related attitudes and practices(KAP).Questionnaires were also administered to the children’s caregivers to identify basic household socio-demographic and economic characteristics,and water,sanitation and hygiene(WASH)conditions.To determine the factors associated with schoolchildren’s nutritional status,mixed logistic regression models were used.Differences and associations were considered statistically significant if P-values were below 0.05.Results:Complete datasets were available for 385 children.The prevalence of undernutrition,stunting and thinness were 35.1%,29.4%and 11.2%,respectively.The multivariable analysis revealed that undernutrition was associated with older age(i.e.12-14 years compared to<12 years;adjusted odds ratio(aOR)=3.45,95%confidence interval(CI)2.12-5.62,P<0.001),multiple pathogenic parasitic infections(aOR=1.87,95%CI 1.02-3.43,P=0.044)and with moderate and severe anaemia in children(aOR=2.52,95%CI 1.25-5.08,P=0.010).Conclusions:We found high prevalence of undernutrition among the children surveyed in the two study regions of Burkina Faso.We further observed that undernutrition,anaemia and parasitic infections were strongly associated.In view of these findings,concerted efforts are needed to address undernutrition and associated risk factors among school-aged children.As part of the VgtS project,WASH,health education and nutritional interventions will be implemented with the goal to improve children’s health.Trial registration:ISRCTN17968589(date assigned:17 July 2015).

Multinational corporations and infectious disease: Embracing human rights management techniques

Background:Global health institutions have called for governments,international organisations and health practitioners to employ a human rights-based approach to infectious diseases.The motivation for a human rights approach is clear:poverty and inequality create conditions for infectious diseases to thrive,and the diseases,in turn,interact with social-ecological systems to promulgate poverty,inequity and indignity.Governments and intergovernmental organisations should be concerned with the control and elimination of these diseases,as widespread infections delay economic growth and contribute to higher healthcare costs and slower processes for realising universal human rights.These social determinants and economic outcomes associated with infectious diseases should interest multinational companies,partly because they have bearing on corporate productivity and,increasingly,because new global norms impose on companies a responsibility to respect human rights,including the right to health.Methods:We reviewed historical and recent developments at the interface of infectious diseases,human rights and multinational corporations.Our investigation was supplemented with field-level insights at corporate capital projects that were developed in areas of high endemicity of infectious diseases,which embraced rights-based disease control strategies.Results:Experience and literature provide a longstanding business case and an emerging social responsibility case for corporations to apply a human rights approach to health programmes at global operations.Indeed,in an increasingly globalised and interconnected world,multinational corporations have an interest,and an important role to play,in advancing rights-based control strategies for infectious diseases.Conclusions:There are new opportunities for governments and international health agencies to enlist corporate business actors in disease control and elimination strategies.Guidance offered by the United Nations in 2011 that is widely embraced by companies,governments and civil society provides a roadmap for engaging business enterprises in rights-based disease management strategies to mitigate disease transmission rates and improve human welfare outcomes.

A decade of innovation to deepen the understanding of infectious diseases of poverty and foster their control and elimination

Exactly 10 years ago,on 25 October 2012,a group of scientists,policy-makers,and practitioners undertook an ambitious project to launch a new open-access journal,named Infectious Diseases of Poverty[1].The idea had originated from a think-tank put forth by the Special Programme for Research and Training in Tropical Diseases(TDR),an organisation co-sponsored by the United Nations Children’s Fund(UNICEF),the United Nations Development Programme(UNDP),the World Bank,and the World Health Organization(WHO).Indeed,this think-tank published a comprehensive Global Report for Research on Infectious Diseases of Poverty[2]that guided the scope and remit of Infectious Diseases of Poverty.