云南省勐海县居民粪类圆线虫感染调查

采用Koga法、Bearmann法、改良加藤氏法对勐海县居民进行粪检,250人中检出粪类圆线虫感染29人,感染率11.60%。采用改良加藤厚涂片法检查254人,虫卵阳性248人,阳性率97.63%。蛔虫、钩虫、鞭虫感染率分别89.76%、70.08%和82.68%。

Epidemiology of pediatric schistosomiasis in hard-to-reach areas and populations:a scoping review

Background Schistosomiasis affects over 250 million people worldwide.Despite children and the poor being key risk groups,limited research and control activities target pre-school aged children(PSAC)and hard-to-reach populations.As endemic countries shift the goals of their schistosomiasis programs from morbidity control to disease elimination,there is a need for inclusive planning to cover all affected age groups from all geographical areas and populations to achieve sustainable impact and health equity.Methods We conducted searches in MEDLINE,Web of Science,Embase(Ovid),and LILACS per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses—Extension for Scoping Reviews(PRISMA-ScR)guidelines.Quality assessment of identified articles was done using the Joanna Briggs Institute Prevalence Critical Appraisal Tool.Relevant study data were extracted from the articles and entered into Microsoft Excel 2016 for descriptive analysis.Results From the 17,179 screened articles,we identified 13 eligible studies on schistosomiasis in PSAC living in hard-to-reach areas and populations.All identified studies were from sub-Saharan Africa.The mean sample size of the retained studies was 572,with a balanced sex distribution among the young children sampled in each study.Ten studies investigated Schistosoma mansoni,one investigated Schistosoma haematobium,while two covered both S.mansoni and S.haematobium in the target population.The prevalence of S.mansoni among PSAC in the included studies was estimated at 12.9%in Ghana,80.3–90.5%in Kenya,35.0%in Madagascar,9.6–78.0%in Senegal,11.2–35.4%in Sierra Leone,44.4–54.9%in Tanzania and 39.3–74.9%in Uganda.Out of the three studies that investigated S.haematobium,the presence of the infection was reported in only one study carried out in Nigeria.Schistosome infections reported in nearly all studies included in this review were of light intensity.Only one study conducted in Nigeria documented visible hematuria in 17.7%of the PSAC studied.Conclusions The findings document the high prevalence of schistosomiasis among PSAC in hard-to-reach populations and underscore the need to consider this population subgroup when designing the expansion of preventive chemotherapy and schistosomiasis control activities.

不同检测方法对粪类圆线虫钩虫检出率的比较

目的用不同方法检查粪便中的粪类圆线虫和钩虫,掌握检测粪类圆线虫的方法。方法在云南省勐海县选择土源性线虫感染率相对高的自然村1个,以户为单位随机抽样,采用改良加藤法(Kato-Katz法)、Koga法和Baerm ann法3种粪便检查方法对粪样进行检查,每人送检粪样3次。结果粪类圆线虫阳性率Kato-Katz法为0,Koga法为11.72%,Baerm ann法为12.55%。钩虫阳性率Kato-Katz法为64.44%,Koga法为57.74%,Baerm ann法为4.60%。结论Baer-m ann法仅适用于粪类圆线虫检测,Koga法可用作钩虫和粪类圆线虫检测,而Kato-Katz法仅适用于钩虫检测。

卫生系统知证政策指导：评估对研究证据的信心

本文是《PLoS Medicine》关于卫生系统知证政策指导三篇系列文章的第三篇,阐述了应如何将证据转化为指导,以形成卫生系统政策,并促进临床和公共卫生干预的实施。其要点如下:①评估不同类型研究证据是决定解决卫生系统问题的政策方案的关键;②鉴于许多卫生系统干预的复杂性,系统透明的评价方法尤为重要;③当前有不少好的工具可用于评价对支持政策制定各阶段不同类型的研究证据的信心,其中评价关于效果的证据最多;④我们需要制定工具来帮助评价其他关键因素的系统评价证据,如政策方案对于利益相关者的可接受性、实施可行性及公平性;⑤还需要进一步研究全球卫生系统指导政策方案的制定、构建及呈现方法。

HIV and intestinal parasite co-infections among a Chinese population: an immunological profile

Background:Parasite infections often result in a switch of the human body’s predominant immune reaction from T-helper 1(Th1)-type to Th2-type.Hence,parasite infections are widely expected to accelerate the progression of human immunodeficiency virus(HIV)infections to acquired immunodeficiency syndrome(AIDS).In the People’s Republic of China,both parasitic diseases and AIDS are epidemic in certain rural areas,and co-infections are relatively common.However,no population-based studies have yet investigated the frequency of HIV and parasite co-infections,and its effects on immune responses.We studied(1)the immune status of an HIV-infected population,and(2)the effect of co-infection of HIV and intestinal parasites on selected parameters of the human immune system.Methods:A total of 309 HIV-infected individuals were recruited and compared to an age-matched and sex-matched control group of 315 local HIV-negative individuals.Questionnaires were administered to all participants to obtain information on sociodemographic characteristics,sanitation habits,family income,and recent clinical manifestations.Two consecutive stool samples and 10 ml samples of venous blood were also collected from each individual for the diagnosis of parasite infections and quantitative measurements of selected cytokines and CD4+T-lymphocytes,respectively.Results:During the study period,79 HIV-infected individuals were not under highly active antiretroviral therapy(HAART)and were thus included in our analysis;the prevalence of intestinal helminth infections was 6.3%and that of protozoa was 22.8%.The most common protozoan infections were Blastocystis hominis(B.hominis)(13.9%)and Cryptosporidium spp.(10.1%).The prevalence of Cryptosporidium spp.in HIV-infected individuals was significantly higher than that in HIV negative individuals(P<0.05).Compared to the non-co-infected population,no significant difference was found for any of the measured immunological indicators(P>0.05).However,the following trends were observed:IFN-γlevels were lower,but the IL-4 level was higher,in the population co-infected with HIV and helminths.In the population co-infected with HIV and B.hominis,the IL-2 level was higher.The population co-infected with HIV and Cryptosporidium spp.had markedly lower CD4+T-lymphocyte counts.Conclusion:According to the immunologic profile, co-infection with helminths is disadvantageous to HIV-infected individuals. It was associated with a shift in the Th1/Th2 balance in the same direction as that caused by the virus itself, which might indicate an acceleration of the progress from an HIV infection to AIDS. Co-infection with Cryptosporidium spp. was not associated with a significant change in immune factors but co-infection with Cryptosporidium spp. was associated with a reduced level of CD4 + T-lymphocytes, confirming the opportunistic nature of such infections. Co-infection with B. hominis, on the other hand, was associated with an antagonistic shift in the immunological profile compared to an HIV infection.

The genetic variation of Angiostrongylus cantonensis in the People’s Republic of China

Background:The People’s Republic of China(P.R.China)is the presumptive home range of the rat lungworm Angiostrongylus cantonensis,a major aetiological agent of human eosinophilic meningitis.We present a study of the genetic variation of A.cantonensis in P.R.China.Our aim was to deepen the current knowledge pertaining to its origin and global spread from a molecular perspective.Methods:Adult A.cantonensis were collected in the frame of a national survey and identified based on morphological criteria.Polymerase chain reaction(PCR)was employed to amplify the target DNA sequences(cytochrome c oxidase subunit I(cox1),nicotinamide adenine dinucleotide dehydrogenase subunit 1(nad1)and internal transcribed spacer(ITS)).The PCR product of cox1 was directly submitted to sequencing,while clone sequencing was used for nad1 and ITS.The identity of the samples was verified by comparing the sequences to those of accepted A.cantonensis specimens.The specific composition of substitutions in each gene was analysed,and the genotypes were compared based on the complete cox1,nad1 and ITS genes.Results:We characterised the complete mitochondrial genes cox1 and nad1 of 130 specimens and obtained 357 nuclear sequences containing two complete ITS(ITS1 and ITS2)and 5.8S rRNA of the same samples.All specimens were genetically confirmed as A.cantonensis.Two major groups(i.e.I and II)were identified according to the phylogeny of cox1 sequences.Group I could be further categorised into six distinct clades.Almost half of the specimens(47.7%)belong to the clade Ia and 22.3%to the group II.The former was widely distributed across the study region.A variable number of repeat units in three microsatellites was observed,resulting in considerable length variation in ITS.Intragenomic variation of ITS sequences was found in a large proportion of the samples.Genotyping showed a striking difference between mitochondrial DNA and ITS.Conclusions:Our results demonstrate that A.cantonensis is the only rat lungworm species in P.R.China and shows high genetic diversity.Results of diversity and genotyping of A.cantonensis can be impacted by the sequencing strategy and biomarker.Although ITS may be a valuable marker for interspecific identification,it is not suitable for studying the intraspecific variation of A.cantonensis due to its high intragenomic variation and current challenges for direct sequencing.

Negligible risk of inducing resistance in Mycobacterium tuberculosis with single-dose rifampicin as post-exposure prophylaxis for leprosy

Post-exposure prophylaxis(PEP)for leprosy is administered as one single dose of rifampicin(SDR)to the contacts of newly diagnosed leprosy patients.SDR reduces the risk of developing leprosy among contacts by around 60%in the first 2–3 years after receiving SDR.In countries where SDR is currently being implemented under routine programme conditions in defined areas,questions were raised by health authorities and professional bodies about the possible risk of inducing rifampicin resistance among the M.tuberculosis strains circulating in these areas.This issue has not been addressed in scientific literature to date.To produce an authoritative consensus statement about the risk that SDR would induce rifampicin-resistant tuberculosis,a meeting was convened with tuberculosis(TB)and leprosy experts.The experts carefully reviewed and discussed the available evidence regarding the mechanisms and risk factors for the development of(multi)drug-resistance in M.tuberculosis with a view to the special situation of the use of SDR as PEP for leprosy.They concluded that SDR given to contacts of leprosy patients,in the absence of symptoms of active TB,poses a negligible risk of generating resistance in M.tuberculosis in individuals and at the population level.Thus,the benefits of SDR prophylaxis in reducing the risk of developing leprosy in contacts of new leprosy patients far outweigh the risks of generating drug resistance in M.tuberculosis.

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.

Efforts to mitigate the economic impact of the COVID-19 pandemic:potential entry points for neglected tropical diseases

Background:The damage inflicted by the coronavirus diseases 2019(COVID-19)pandemic upon humanity is and will continue to be considerable.Unprecedented progress made in global health over the past 20 years has reverted and economic growth has already evaporated,giving rise to a global recession,the likes of which we may not have experienced since the Second World War.Our aim is to draw the attention of the neglected tropical disease(NTD)community towards some of the major emerging economic opportunities which are quickly appearing on the horizon as a result of COVID-19.Main text:This scoping review relied on a literature search comprised of a sample of articles,statements,and press releases on initiatives aimed at mitigating the impact of COVID-19,while supporting economic recovery.Of note,the donor scenario and economic development agendas are highly dynamic and expected to change rapidly as the COVID-19 pandemic unfolds,as are donor and lender priorities.Con elusions:The NTD community,particularly in low-and middle-income countries(LMICs),will need to work quickly,diligently,and in close collaboration with decision-makers and key stakeholders,across sectors at national and international level to secure its position.Doing so might enhance the odds of grasping potential opportunities to access some of the massive resources that are now available in the form of contributions from corporate foundations,trust funds,loans,debt relieve schemes,and other financial mechanisms,as part of the ongoing and future economic development agendas and public health priorities driven by the COVID-19 pandemic.This paper should serve as a starting point for the NTD community to seek much needed financial support in order to sustain and revitalize control and elimination efforts pertaining to NTDs in LMICs.

High prevalence of urinary schistosomiasis in a desert population: results from an exploratory study around the Ounianga lakes in Chad

Background Researching a water-borne disease in the middle of the Sahara desert might not seem the most relevant concern.However,nomadic Sahelian pastoralists health concerns regarding their livestock and anecdotal reports about trematode infections of Fasciola spp.and Schistosoma spp.in desert-raised animals justified an exploratory study focusing on the lakes of Ounianga in Northern Chad.The aim was to test whether trematode parasites such as Schistosoma spp.occur in human populations living around the Sahara desert lakes of Ounianga Kebir and Ounianga Serir in northern Chad.Methods The study was carried out in January 2019 and comprised of three components.First,a cross sectional survey based on a random sample drawn from the population to detect infections with S.haematobium and S.mansoni;second,focus group discussions exploring disease priorities,access to health and health seeking behaviour;and third,surveying water contact sites for intermediate host snails.Samples of trematode parasites and snails were confirmed on species level by molecular genetic methods.For parasitological and malacological surveys descriptive statistics were performed.Qualitative data analysis included the full review of all transcripts,followed by a descriptive and explorative thematic analysis.Results Among 258 participants,the overall S.haematobium prevalence using urine filtration was 39.2%[95%confidence interval(CI):33.5–45.1%],with 51.5%of the infected suffering from heavy infection.The intermediate host snail of S.haematobium(Bulinus truncatus)occurred at water contact sites near both study villages,revealing the potential for local transmission.Although a positive S.mansoni point-of-care circulating cathodic antigen(POC-CCA)test result was obtained from 8.6%(95%CI 5.7–12.8%)of the samples,no intermediate host snails of S.mansoni were found,and the relevance of S.mansoni remains uncertain.Qualitative findings underline the importance of morbidity caused by urinary schistosomiasis,and the lack of access to diagnostics and treatment as a major health concern.Conclusions This research revealed a high prevalence of urinary schistosomiasis in the population living around the lakes of Ounianga in the Sahara,a United Nations Educational,Scientific and Cultural Organization(UNESCO)world heritage site in Chad.Despite the high public health importance of the associated morbidity expressed by the population,there is no access to diagnostics and treatment.Further work is needed to develop and test a context-adapted intervention.

Co-infection of HIV and parasites in China: Results from an epidemiological survey in rural areas of Fuyang city, Anhui province, China

The aim of this study was to investigate epidemiological characteristics of co-infection of HIV and intestinal parasites in a HIV/AIDS highly endemic area in China.A cross-sectional survey was carried out in two villages where HIV/AIDS prevalence in residents was over 1%.Stool samples of all residents in the two targeted villages were examined for the presence of intestinal parasites.Blood examination was performed for the HIV infection detection and anemia test.A questionnaire survey was carried out in all residents participating in the study.A total of 769 individuals were enrolled in the investigation,720 of whom were involved in stool examination of intestinal parasites.The infection rates of parasites in the residents of the targeted villages were as follows:0.56%for Ascaris lumbricoides,4.03%for Hookworm,0.28%for Trichuris trichiura,0.42%for Clonorchis sinensis,21.39%for Blastocystis hominis,3.89%for Giardia lamblia,1.67%for Entamoeba spp.,4.44%for Cryptosporidium spp.,and no infection for Strongyloides stercoralis.The overall infection rate of intestinal worms was 4.72%,intestinal parasite infection rate was 24.31%,the anemia prevalence rate was 34.68%,the co-infection rate of HIV and intestinal helminthes 2.17%,the co-infection rate of HIV and intestinal protozoa 28.26%,of which the co-infection rates of HIV and Blastocystis hominis,and HIV and Cryptosporidium spp.were 19.57%and 13.04%,respectively.A significant difference of Cryptosporidium spp.infection rate was found between HIV-positive group(13.04%)and HIV-negative group(4.70%)(P<0.05).Higher prevalence of anemia(34.68%)occurred in the study villages,particularly in children(>50%)and women(>39%).It was concluded that the infection rate of intestinal protozoa in the residents was higher than that of intestinal helminthes in the local setting,and a same pattern appeared in the co-infection rate of HIV and parasites.An interestingfinding is that the infection rate of Cryptosporidium spp.among the HIV-positives was significantly higher than that in the HIV-negatives,and children and women had higher anemia prevalence.

Spatio-temporal analysis of leprosy risks in a municipality in the state of Mato Grosso-Brazilian Amazon: results from the leprosy post-exposure prophylaxis program in Brazil

Background Leprosy post-exposure prophylaxis(LPEP)with single dose rifampicin(SDR)can be integrated into different leprosy control program set-ups once contact tracing has been established.We analyzed the spatio-temporal changes in the distribution of index cases(IC)and co-prevalent cases among contacts of leprosy patients(CP)over the course of the LPEP program in one of the four study areas in Brazil,namely the municipality of Alta Floresta,state of Mato Grosso,in the Brazilian Amazon basin.Methods Leprosy cases were mapped,and socioeconomic indicators were evaluated to explain the leprosy distribution of all leprosy cases diagnosed in the period 2016–2018.Data were obtained on new leprosy cases[Notifiable diseases information system(Sinan)],contacts traced by the LPEP program,and socioeconomic variables[Brazilian Institute of Geography and Statistics(IBGE)].Kernel,SCAN,factor analysis and spatial regression were applied to analyze changes.Results Overall,the new case detection rate(NCDR)was 20/10000 inhabitants or 304 new cases,of which 55 were CP cases among the 2076 examined contacts.Changes over time were observed in the geographic distribution of cases.The highest concentration of cases was observed in the northeast of the study area,including one significant cluster(Relative risk=2.24;population 27427,P-value<0.001)in an area characterized by different indicators associated with poverty as identified through spatial regression(Coefficient 3.34,P-value=0.01).Conclusions The disease distribution was partly explained by poverty indicators.LPEP influences the spatial dynamic of the disease and results highlighted the relevance of systematic contact surveillance for leprosy elimination.

The fight against lymphatic filariasis:perceptions of community drug distributors during mass drug administration in coastal Kenya

Background:Lymphatic filariasis(LF)#a neglected tropical disease(NTD)and leading cause of global disability,is endemic in 32 countries in Africa with almost 350 million people requiring regular drug administration,and only 16 countries achieving target coverage.Community Drug Distributors(CDDs)are critical for the success of NTD programs,and the distribution of medicines during mass drug administration(MDA)in Africa;however they could also be a weak link.The primary aim of this study is to explore and describe perceptions of CDDs during MDA for LF in Mvita sub-county in Mombasa county and Kaloleni sub-county in Kilifi county,Kenya;and provide recommendations for the effective engagement of communities and CDDs in low-resource settings.Methods:In September 2018,we conducted six focus group discussions with community members in each sub-county,three with men aged 18-30,31-50,and 51 years and above and three with women stratified into the same age groups.In each sub-county,we also conducted semi-struaured interviews with nine community health extension workers(CHEWs),the national LF focal point,the county NTD focal points,and seven community leaders.Content analysis of the data was conducted,involving a process of reading,coding,and displaying data in order to develop a codebook.Results:We found that several barriers and facilitators impact the engagement between CDDs and community members during MDA.These barriers include poor communication and trust between CDDs and communities;community distrust of the federal government;low community knowledge and perceived risk of LF,poor timing of MDA,fragmented supervision of CDDs during MDA;and CDD bias when distributing medicines.We also found that CDD motivation was a critical factor in their ability to successfully meet MDA targets.It was acknowledged that directly observed treatment and adequate health education were often not executed by CDDs.The involvement of community leaders as informal supervisors of CDDs and community members improves MDA.Conclusions:In order to achieve global targets around the elimination of LF,CDDs and communities must be effectively engaged by improving planning and implementation of MDA.

A comprehensive research agenda for zero leprosy

Background: Leprosy control achieved dramatic success in the 1980s–1990s with the implementation of short course multidrug therapy,which reduced the global prevalence of leprosy to less than 1 in 10000 population.However,a period of relative stagnation in leprosy control followed this achievement,and only limited further declines in the global number of new cases reported have been achieved over the past decade.Main text In 2016,major stakeholders called for the development of an innovative and comprehensive leprosy strategy aimed at reducing the incidence of leprosy,lowering the burden of disability and discrimination,and interrupting transmission.This led to the establishment of the Global Partnership for Zero Leprosy(GPZL)in 2018,with partners aligned around a shared Action Framework committed to achieving the WHO targets by 2030 through national leprosy program capacity-building,resource mobilisation and an enabling research agenda.GPZL convened over 140 experts from more than 20 countries to develop a research agenda to achieve zero leprosy.The result is a detailed research agenda focusing on diagnostics,mapping,digital technology and innovation,disability,epidemiological modelling and investment case,implementation research,stigma,post exposure prophylaxis and transmission,and vaccines.This research agenda is aligned with the research priorities identified by other stakeholders.Conclusions: Developing and achieving consensus on the research agenda for zero leprosy is a significant step forward for the leprosy community.In a next step,research programmes must be developed,with individual components of the research agenda requiring distinct expertise,varying in resource needs,and operating over different timescales.Moving toward zero leprosy now requires partner alignment and new investments at all stages of the research process,from discovery to implementation.

Disability progression among leprosy patients released from treatment:a survival analysis

Background:Leprosy can be cured,but physical disability(PD)as a result of the infection can progress in the postrelease from treatment phase.This study evaluated the likelihood of,and factors associated with,the progression of the PD grade post-release from treatment among leprosy patients treated in Cáceres-MT,Brazil in the period 2000 to 2017.Methods:A retrospective cohort study and survival analysis were performed in the hyperendemic municipality of Cáceres in the state of Mato Grosso.The study population consisted of newly diagnosed leprosy patients released from treatment between January 1,2000 and December 31,2017.The main outcome was the progression of the PD grade with regard to probability and time;and the evaluated covariates included clinical,operational and demographic variables.The Cox proportional risk model was used to estimate the risk ratio(Hazard Ratios)of the covariates.Both an univariate and a multivariate analysis were implemented,with 95%confidence intervals.Results:The mean time for progression of the PD grade was 162 months for PB and 151 months for MB leprosy patients.The survival curve showed that 15 years after the release from treatment,the probability of PD grade progression was 35%,with no difference between PB and MB or age groups.Leprosy reactions and registered medical complaints of any kind during treatment were identified as risk factors with Hazard Ratios of 1.6 and 1.8 respectively.Conclusions:People released from treatment as cured of leprosy are susceptible to worsening of the PD,especially those who have had complications during multi-drug therapy treatment.This indicates that leprosy patients should be periodically monitored,even after the successful completion of multidrug therapy.