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The fresh water snail Biomphalaria pfeifferi is the intermediate host for Schistosoma mansoni, which causes human intestinal schistosomiasis in Zimbabwe. Despite the medical importance of this intermediate host, there are no current data on its molecular characterization in Zimbabwe. In 2016, human water contact sites were identified in four communities in Madziwa area, Shamva district, Zimbabwe. The survey sites were recorded and mapped using a global positioning system. A 655 bp region of the mitochondrial cytochrome oxidase subunit I gene was amplified in 70 B. pfeifferi snails. The sequence data were analysed to determine the relationships between the individual snails, their inter, intra population diversity and structure. Overall, four unique cox1 haplotypes, with a haplotype diversity of 0.608, were identified in the snails. One haplotype spanned across most of the sites. There was no clear geographical clustering of haplotypes. The mean diversity among the haplotypes was very low (0.009), while the net divergence among the collection sites ranged from 0.000 to 0.026. The diversity within and between the sites was 0.017 and 0.012 respectively. This data advances our knowledge of the understanding of the population structure of B. pfeifferi in Madziwa area, Zimbabwe, with the high occurrence of one haplotype indicating the possibility of a recent bottleneck followed by population expansion. The population genetic structure of B. pfeifferi snails described here has provided an opportunity to investigate the contribution of snail genetics to variation in disease burden; and development of control strategies that exploit genetic differences in susceptibility to parasites.

The burden of schistosomiasis remains a global public health problem, especially in sub-Saharan Africa despite progress in terms of morbidity control. Successful control efforts achieved by China in the last six decades came with considerable experience and lessons that could benefit schistosomiasis control programs in other endemic countries. China's role and commitment to global health cooperation has become increasingly important; this has created a platform for partnership with developing partners for the establishment of Forum on China–Africa health cooperation which prioritizes the pursuit of global elimination target for schistosomiasis and malaria, control of HIV/AIDS, and improved access to reproductive health care. Chinese government's commitment towards achieving schistosomiasis elimination in Africa prompted the establishment of Institution-based Network on China–Africa Cooperation for Schistosomiasis Elimination (INCAS), by the National Institute of Parasitic Diseases to promote schistosomiasis elimination in Africa. Schistosomiasis experts from six provincial institutions and counterparts from 10 African countries participated in the first workshop on China–Africa cooperation for Schistosomiasis Elimination in Africa at Lilongwe, Malawi, in 2015. Experts at the inaugural meeting shared experiences from their national schistosomiasis control programs, as well as identified areas for collaborative synergy targeting schistosomiasis elimination in Africa. The establishment of INCAS, which comprises of 28 member-institutions from China and Africa, was proposed at this meeting. We, therefore, provide information on INCAS activities, cooperation mechanism, as well as assess the strengths, weaknesses, opportunities, and threats as we target schistosomiasis elimination in Africa using the INCAS platform.

Cysticercosis remains a public health problem in China, with disease prevalence attributed to poor socio-economic and public health conditions. This parasitic food-borne disease was prioritized for effective control following implementation of the national surveys on parasitic diseases carried out in China. We predicted the cysticercosis distribution in Dali, Yunnan Province by assessing spatio-temporal distribution characteristics between 2000 and 2014 to better understand the trend of the disease incidence. A database of cysticercosis cases was provided by the clinical department at the Dali Prefectural Institute of Research and Control of Schistosomiasis. Describing the epidemiological features of cysticercosis and analyzing its spatiotemporal distribution of cases using mapping, scanning and spatial autocorrelation analysis, our findings found a total of 3,347 patients with cysticercosis infection, neurocysticercosis in particular. Cysticercosis prevalence was the highest among young and middle-aged male farmers, and also predominant among the Bai nationality. Three aggregation areas were identified during the period 2000-2014. Hotspot analysis implicated Dali City, Eryuan County and Yangbi County between 2000 and 2007, with areas gradually shifting towards the western and northern parts of the province. The hotspot map indicated that Eryuan County was a constant problem with respect to cysticercosis. The results indicated three cysticercosis clusters in Dali that could be attributed to environmental factors and unhealthy lifestyles. Multi-sectoral control initiatives are, therefore, recommended in these areas to effectively control and prevent cysticercosis among the population.

BackgroundBulinusspecies are freshwater snails that transmit the parasitic trematodeSchistosoma haematobium. Despite their importance, the diversity of these intermediate host snails and their evolutionary history is still unclear in Zimbabwe.Bulinus globosusandB. truncatuscollected from a urogenital schistosomiasis endemic region in the Madziwa area of Zimbabwe were characterized using molecular methods.MethodsMalacological survey sites were mapped and snails were collected from water contact sites in four communities in the Madziwa area, Shamva district for a period of one year, at three-month intervals.Schistosoma haematobiuminfections in snails were determined by cercarial shedding and the partial mitochondrial cytochromecoxidase subunit 1 gene (cox1) was used to investigate the phylogeny and genetic variability of theBulinusspp. collected.ResultsAmong the 1570Bulinusspp. snails collected, 30 (1.9%)B. globosuswere shedding morphologically identified schistosomes. None of theB. truncatussnails were shedding. The mitochondrialcox1 data from 166 and 16 samples forB. globosusandB. truncatus, respectively, showed genetically diverse populations within the two species. Twelvecox1 haplotypes were found from the 166B. globosussamples and three from the 16B. truncatussamples with phylogenetic analysis showing that the haplotypes fall into well-supported clusters within their species groups. BothB. truncatusandB. globosusclustered into two distinct lineages. Overall, significant negative values for both Tajima’s D statistic and the Fu’s Fs statistic were observed forB. globosusandB. truncatus.ConclusionsThe study provided new insights into the levels of genetic diversity withinB. globosusand additional information onB. truncatuscollected from a small geographical area in Zimbabwe. Low prevalence levels of infection observed in the snails may reflect the low transmission level of urogenital schistosomiasis in the area. Our results contribute towards the understanding of the distribution and population genetic structure ofBulinusspp. supporting the mapping of the transmission or risk of transmission of urogenital schistosomiasis, particularly in Zimbabwe.

Introduction: Plasmodium vivax (Pv) and P. knowlesi account together for a considerable share of the global burden of malaria, along with P. falciparum (Pf). However, inaccurate diagnosis and undetectable asymptomatic/submicroscopic malaria infections remain very challenging. Blood-stage antigens involved in either invasion of red blood cells or sequestration/cytoadherence of parasitized erythrocytes have been immunomics-characterized, and are vital for the detection of malaria incidence. Areas covered: We review the recent advances in Plasmodium immunomics to discuss serological markers with potential for specific and sensitive diagnosis of malaria. Insights on alternative use of immunomics to assess malaria prevalence are also highlighted. Finally, we provide practical applications of serological markers as diagnostics, with an emphasis on dot immunogold filtration assay which holds promise for malaria diagnosis and epidemiological surveys. Expert commentary: The approach largely contributes to Pf and Pv research in identifying promising non-orthologous antigens able to detect malaria incidence and to differentiate between past and recent infections. However, further studies to profiling naturally acquired immune responses are expected in order to help discover/validate serological markers of no cross-seroreactivity and guide control interventions. More so, the application of immunomics to knowlesi infections would help validate the recently identified antigens and contribute to the discovery of additional biomarkers of exposure, immunity, or both.

Background The development of agenda for global schistosomiasis elimination as a public health problem generates enthusiasms among global health communities, motivating great interests in both research and practice. Recent China-Africa schistosomiasis control initiatives, aiming to enhance collaboration on disease control in African countries, reflect in part that momentum. Yet there is a pressing need to know whether the Chinese experiences can be translated and applied in African settings. Main body China’s remarkable achievements in schistosomiasis control programme, associated experiences and lessons, have much to offer to those combating the disease. Central to the success of China’s control programmes is a strategy termed “integrated control” – integrating environmental approaches (e.g. improved sanitation, agricultural and hydrological development and management), which target different phases of the parasite transmission system, to chemical-based drug treatment and mollusciciding. Yet, despite significant measurable public health benefits, such integration is usually based on field experience and remains largely uncharacterized in an ecological context. This has limited our knowledge on relative contributions of varying components of the integrated control programme to the suppression of disease transmission, making it challenging to generalize the strategy elsewhere. In this opinion article, we have described and discussed these challenges, along with opportunities and research needs to move forward. Conclusions There is an urgent need to formalize an ecological framework for the integrated control programme that would allow research towards improved mechanistic understanding, quantification, and prediction of the control efforts. Electronic supplementary material The online version of this article (10.1186/s40249-018-0506-4) contains supplementary material, which is available to authorized users.

Schistosomiasis was one of the most prevalent severe infectious diseases in China. Most of the control plans implemented were based on local settings; thus, the national schistosomiasis control program involved different control phases. These included a working mechanism based on multisectoral cooperation which involved government at all levels, communities, and professionals. It also involved updating the technical strategies and interventions through intensive research, to provide adequate support for programs at different stages with changing natural and social features. To commemorate the 61st anniversary of publishing Chairman Mao Zedong's two poems titled Farewell to the god of plague, we have distilled lessons learnt from national schistosomiasis control programs, which could be transferred to other endemic countries. Based on this work, we published a series of articles to demonstrate the successive programs in different areas or levels in China, and also discussed how best to apply those successive experiences into African countries where schistosomiasis is still a public health problem. There are three major lessons learnt from the Chinese national schistosomiasis control program over the last six decades: (1) sustained commitment by the Chinese governments, from central to local levels; (2) continuous update of control strategies and interventions applied at the village level, based on local settings; and (3) maintaining surveillance-response systems implementation in programs at all levels. With sustained efforts, only 37,000 patients including 2.9% advanced patient cases were found in the country, with six provinces out of the 12 endemic provinces yet to achieve transmission interruption, based on the epidemiological report in 2017. Therefore, Chinese experiences in disease control program are sufficient to promote disease control programs in other developing countries, which would also improve the visibility of Chinese contribution to the world disease control programs. Pursuit of this global engagement will also provide the impetus to maintain our surveillance-response capacity in the post-elimination stage. Download : Download full-size image

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. Electronic supplementary material The online version of this article (doi:10.1186/s40249-017-0303-5) contains supplementary material, which is available to authorized users.

The burden of soil-transmitted helminths (STHs) infections in Nigeria is enormous with serious public health significance. This study, therefore, assessed helminthiasis among school-age children and the hygiene conditions of schools in Lafia, Nasarawa State, Nigeria between December 2015 and April 2016 from four randomly selected primary schools. Stool samples were collected from 200 primary school pupils including 80 males (40%) and 120 females (60%) between five and 16 years, using clean sample bottles and a standard parasitology examination technique at the central laboratory at the Federal University, Lafia. An overall prevalence of 33.5% (67/200) helminths infections was recorded. A checklist of Ascaris lumbricoides, hookworm, Trichuris trichiura, and Strongyloides stercoralis was generated from the pooled data of the four studied schools in which A. lumbricoides occurred highest with 13% (26/200) while S. stercoralis was the least prevalent at 2.50% (5/200). Among the schools sampled, St. James Pilot Science Primary School’s children were the most infected at 44% (22/50). Multiple infections were observed in three of the four schools sampled. There was no significant difference (p > 0.05) in prevalence rates of different STHs infections in relation to age group and gender across schools. Our findings showed that the hygiene conditions in the studied schools were poor without water, hand washing materials, refuse bins, as well as poor sanitary conditions. This study also identified ova and larvae of STHs parasites in the analyzed soil samples from the studied schools. Most school-age children had knowledge about contamination but few among them washed their hands with water and soap. The obtained result indicated a negative association between the prevalence of STHs and the proportion of pupils that cleaned up with water after defection. We, therefore, advise that hygiene conditions in schools be improved and that the government should prioritize enrolling all primary schools in Nasarawa state for the school health program so as to reduce the burden of STHs among school-age children in the state.

The geographical distribution of snail (i.e., the intermediate host of schistosomiasis) is consistent with that of endemic areas. The suitable snail habitus requires necessary environmental conditions for snail population. The high-resolution remote sensing provides an important tool for the spatio-temporal analysis of disease monitoring and prediction. This study conducted a typical schistosomiasis epidemic area in the marshland and lake regions along the Yangtze River, Yueyang City, Hunan Province of China. And three types of environmental factors, i.e., NDVI, soil moisture, and shortest distance to water body, associated with the geographical distribution of snail population, were extracted from the high-resolution remoting sensing data. The predicted distribution of snail habitus from the high-resolution environmental factors were compared with the data of annual program of snail survey. The results have shown that the application of high-resolution remote sensing can improve the accuracy of the modeled and predicted the potential risk areas of schistosomiasis, and may become an important tool for the ongoing national schistosomiasis control program.

BackgroundAchatina fulica, the giant African snail, is the largest terrestrial mollusk species. Owing to its voracious appetite, wide environmental adaptability, high growth rate, and reproductive capacity, it has become an invasive species across the world, mainly in Southeast Asia, Japan, the western Pacific islands, and China. This pest can damage agricultural crops and is an intermediate host of many parasites that can threaten human health. However, genomic information of A. fulica remains limited, hindering genetic and genomic studies for invasion control and management of the species.FindingsUsing a k-mer–based method, we estimated the A. fulica genome size to be 2.12 Gb, with a high repeat content up to 71%. Roughly 101.6 Gb genomic long-read data of A. fulica were generated from the Pacific Biosciences sequencing platform and assembled to produce a first A. fulica genome of 1.85 Gb with a contig N50 length of 726 kb. Using contact information from the Hi-C sequencing data, we successfully anchored 99.32% contig sequences into 31 chromosomes, leading to the final contig and scaffold N50 length of 721 kb and 59.6 Mb, respectively. The continuity, completeness, and accuracy were evaluated by genome comparison with other mollusk genomes, BUSCO assessment, and genomic read mapping. A total of 23,726 protein-coding genes were predicted from the assembled genome, among which 96.34% of the genes were functionally annotated. The phylogenetic analysis using whole-genome protein-coding genes revealed that A. fulica separated from a common ancestor with Biomphalaria glabrata ∼182 million years ago.ConclusionTo our knowledge, the A. fulica genome is the first terrestrial mollusk genome published to date. The chromosome sequence of A. fulica will provide the research community with a valuable resource for population genetics and environmental adaptation studies for the species, as well as investigations of the chromosome-level of evolution within mollusks.

Genetics combined with proteomics allows for a better understanding of parasite-host interactions and host immune responses. Immunomics elucidates that antigens are targets of induced or naturally acquired immunity (NAI), a promising solution to the challenge of eradicating human infections. High-throughput protein microarrays enhance rapid antigen discovery for the development of serodiagnostic tests/vaccines. Areas covered: This review systematically analyzes the emergence of protein microarrays as a powerful technology for parasite antigen discovery and subsequently summarizes some of the attributes and disadvantages of these approaches. Major insights on novel/validated serological biomarkers or vaccine candidates against malaria and Neglected Tropical Diseases (NTDs) are highlighted. We conclude with a brief description of the processes involved in immunomic protein microarrays. Expert commentary: Interesting discoveries have been made using protein microarrays. However, there is a need to evaluate targets that elicit strong immunogenicity and correlates of protective efficacy to aid prioritization and guide further clinical development. The goal of parasitic disease elimination will be best achieved through an integrated strategy that will incorporate and implement the different control components.

In most endemic sub-Saharan African countries, repeated infections with soil-transmitted helminth (STH) occur as early as six weeks after the end of mass drug administration (MDA) with albendazole. In this study, we designed a new health educational board game Worms and Ladders and evaluated its potential to complement MDA with albendazole and reduce reinfection rates through the promotion of good hygiene practices among school-aged children. The evaluation employed a randomized control trial (RCT) design. Baseline knowledge, attitude and practices (KAP) relating to STH were obtained using a questionnaire from 372 pupils across six schools in Abeokuta, Nigeria. Schools were randomly assigned into intervention and control group, with the former and latter receiving Worms and Ladders and the common Snake and Ladder board game respectively. Fresh stool samples were also collected at baseline for STH diagnosis before administering 400mg single dose albendazole. Follow-up assessments of STH burden and KAP were conducted three and six months' post-intervention. Data generated from the study were analyzed using SPSS 20.0 software, with confidence interval set at 95%. Prevalence of STH dropped from 25.0% to 10.4% in the intervention group and 49.4% to 33.3% in the control group at three months' post-intervention. The prevalence further dropped to 5.6% in the intervention group at six months’ post-intervention. However, it increased to 37.2% in the control group at six months' post-intervention. There was a significant difference (p, Author summary School-aged children are the most affected group of people in terms of burden due to soil-transmitted helminth infections. Unfortunately, the available treatment programme with albendazole cannot prevent reinfection. Health and hygiene education has been recommended to be effective at reducing the rate of STH infections through increased knowledge about transmission and improved hygiene attitude and practices. We, therefore, developed a health educational board game Worms and Ladders and evaluated its potential to complement treatment and reduce reinfection rates. Our findings show that the worm burden dropped significantly among children who played the newly developed game, compared to other children who played another game. The knowledge, attitude and practices of the children as regards STH also improved significantly. The Worms and Ladders board game, therefore, has the potential to promote good hygiene behavior, which in turn translated to a reduced rate of infections. These findings present the newly developed game as a reliable tool to complement mass drug administration campaigns for STH control.

The transmission of some schistosome parasites is dependent on the planorbid snail hosts. Bulinus truncatus is important in urinary schistosomiasis epidemiology in Africa. Hence, there is a need to define the snails’ phylogeography. This study assessed the population genetic structure of B. truncatus from Giza and Sharkia (Egypt), Barakat (Sudan) and Madziwa, Shamva District (Zimbabwe) using mitochondrial cytochrome oxidase subunit 1 gene (COI) and internal transcribed spacer 1 (ITS 1) markers. COI was sequenced from 94 B. truncatus samples including 38 (Egypt), 36 (Sudan) and 20 (Zimbabwe). However, only 51 ITS 1 sequences were identified from Egypt (28) and Sudan (23) (because of failure in either amplification or sequencing). The unique COI haplotypes of B. truncatus sequences observed were 6, 11, and 6 for Egypt, Sudan, and Zimbabwe, respectively. Also, 3 and 2 unique ITS 1 haplotypes were observed in sequences from Egypt and Sudan respectively. Mitochondrial DNA sequences from Sudan and Zimbabwe indicated high haplotype diversity with 0.768 and 0.784, respectively, while relatively low haplotype diversity was also observed for sequences from Egypt (0.334). The location of populations from Egypt and Sudan on the B. truncatus clade agrees with the location of both countries geographically. The clustering of the Zimbabwe sequences on different locations on the clade can be attributed to individuals with different genotypes within the population. No significant variation was observed within B. truncatus populations from Egypt and Sudan as indicated by the ITS 1 tree. This study investigated the genetic diversity of B. truncatus from Giza and Sharkia (Egypt), Barakat area (Sudan), and Madziwa (Zimbabwe), which is necessary for snail host surveillance in the study areas and also provided genomic data of this important snail species from the sampled countries.

Schistosoma japonicum, differs from the African species including S. mansoni and S. haematobium, is a zoonotic parasite as it infects both human and animals including domestic ruminant animals such as cattle and animals from the wild. Considering China's success story in the elimination of schistosomiasis, the China-Africa collaboration on schistosomaisis elimination in Africa is an important cooperative health development initiative. This review examines the importance of China-Africa collaboration on schistosomiasis elimination using effective surveillance-response intervention strategy as the platform to effectively drive the elimination of schistosomiasis in Africa. Three conclusions were made after reviewing the similarity and differences in schistososmiasis control programmes between China and African continent as follows: (i) Politically, China's lessons is that leveraging on the integrated control strategies and the recognition that schistosomiasis is a public health problem which prompted the interest of government in China. It is necessary for African leaders and governments to recognize schistosomiasis as a public health challenge that must be given serious attention in terms of funding and setting up frameworks to complement control efforts. (ii) Technically, efficient monitoring and surveillance system mechanism will facilitate contextual and effective management of schistosomiasis elimination across different environment, and African programme managers should embrace the use of appropriate diagnostic tools to guide treatment strategies at different thresholds of schistosomiasis control. (iii) Strategically, effective control of snail intermediate hosts and precision mapping of snail distribution should be prioritized for successful schistosomiasis elimination in Africa.

Oncomelania hupensis plays a significant role in the transmission of schistosomiasis japonica, which remains a major public health concern in China. Understanding the biological characteristics of O. hupensis is a prerequisite for its control; however, there are currently no studies investigating the intestinal microbiota of the O. hupensis snail. This study aimed to profile the intestinal microbiome of O. hupensis across different ecological landscapes in mainland China. DNA was extracted from the intestines of the collected snails and the bacterial communities were detected using 454 pyrosequencing. A total of 3,799 operational taxonomic units (OTUs) were obtained, and Proteobacteria, Firmicutes, and Actinobacteria were identified as the dominant bacterial taxa at the phylum level. Bacillus and Lactococcus were the most common genera in samples obtained from the four ecological landscapes. Snail specimens were clustered into three clades according to microbial community diversity, and thirty-seven genera that contributed to differential microbiota distributions were identified. Co-occurrence network analysis indicated a symbiotic relationship for the intestinal microbiota of O. hupensis, and PICRUSt analysis predicted forty-one metabolic functions in all snail samples, including membrane transport, amino acid metabolism, carbohydrate metabolism, replication and repair, energy metabolism, as well as xenobiotics biodegradation and metabolism. These findings improve our understanding of bacterial ecology in the O. hupensis intestine; further studies will focus on the relationship between O. hupensis intestinal microbiota and the microbiota in their specific ecological environments.

Background China has made progress in malaria control and aims to eliminate malaria nationwide, but implementing effective interventions along the border regions remain a huge task. The Plasmodium falciparum cases imported from Southeast Asia has frequently reported especially in the China-Myanmar border (CMB) area. Though, information is scant on P. falciparum genetic variability in this area. Methods This study reported P. falciparum isolates genome sequence of six clinical isolates in the CMB area. Furthermore, we estimated the nucleotide diversity, Watterson’s estimator and Tajima’s D value for the whole genome mutation rate in slide window. Results Our data were aligned onto 96.05–98.61% of the reference 3D7 genome in high fold coverages. Principal component analysis result showed that P. falciparum clustered generally according to their geographic origin. A total of 91 genes were identified as positive selection with Ka/Ks ratio significantly higher than 1, and most of them were multigene families encoding variant surface antigens (VSAs) such as var, rif and stevor. The enrichment of the positive selection on VSA genes implied that the environment complexity subjected CMB’s P. falciparum to more pressure for survival. Conclusions Our research suggests that greater genetic diversity in CMB area and the positive selection signals in VSA genes, which allow P. falciparum to fit the host immune system well and aggravate the difficulty of treatment. Meanwhile, results obtained from this study will provide the fundamental basis for P. falciparum population genomic research in CMB area. Electronic supplementary material The online version of this article (10.1186/s40249-018-0493-5) contains supplementary material, which is available to authorized users.

Background Snail intermediate hosts play active roles in the transmission of snail-borne trematode infections in Africa. A good knowledge of snail-borne diseases epidemiology particularly snail intermediate host populations would provide the necessary impetus to complementing existing control strategy. Main body This review highlights the importance of molecular approaches in differentiating snail hosts population structure and the need to provide adequate information on snail host populations by updating snail hosts genome database for Africa, in order to equip different stakeholders with adequate information on the ecology of snail intermediate hosts and their roles in the transmission of different diseases. Also, we identify the gaps and areas where there is need for urgent intervention to facilitate effective integrated control of schistosomiasis and other snail-borne trematode infections. Conclusions Prioritizing snail studies, especially snail differentiation using molecular tools will boost disease surveillance and also enhance efficient schistosomaisis control programme in Africa. Electronic supplementary material The online version of this article (10.1186/s40249-018-0401-z) contains supplementary material, which is available to authorized users.

A cross-sectional survey was carried out in primary schools to determine prevalence, intensity and spatial co-distribution of Schistosomiasis and soil transmitted helminths (STH) infections in Ogun State, Nigeria. A total of 2148 pupils from 42 schools were examined forSchistosomaand STH infections from urine and fresh fecal samples respectively. Ethyl ether concentration method prepared in sodium acetate – acetic acid – formalin ether was used to concentrate parasites’ ova before microscopic examination. The overall prevalence of schistosomiasis and STH infections were 4.0% (95% CI = 3.21–4.92) and 34.64% (95% CI = 32.62–36.69) respectively.Schistosoma haematobiumandAscaris lumbricoideswere the most prevalent across the study area among theSchistosomaand STH species respectively. Overall, intensity of infection was higher in males than in females for allSchistosomaand STH infections, but with no significant difference (P > 0.05), except forTrichuris trichiura(χ2 = 6.490,P χ2 = 12.953,P Schistosomaand STH infections occurred in 15 (35.7%) out of 42 schools, and only 30 children (1.4%) had co-infection ofSchistosomaand STH. This study provides information on the prevalence and spatial risk of schistosomiasis and STH in Ogun State. This will serve as decision-support tool for Ogun State programme managers to help facilitate integration of schistosomiasis and STH control.

Objective Schistosomiasis and intestinal helminthiasis are major public health problems with school-aged children considered the most at-risk group. Pre-school aged children (PSAC) are excluded from existing control programs because of limited evidence of infections burden among the group. We assessed the prevalence of infections and effect on nutritional status of preschool aged children in Abeokuta, Southwestern Nigeria. Results A community-based cross-sectional study involving 241 children aged 0–71 months was conducted in 4 sub-urban communities of Abeokuta. Urine and faecal samples were collected for laboratory diagnosis for parasites ova. Nutritional status determined using age and anthropometric parameters was computed based on World Health Organization 2006 growth standards. Data were subjected to descriptive statistics analysis, Chi square, t-test and ANOVA. Of 167 children with complete data, 8 (4.8%) were infected with Schistosoma haematobium; Schistosoma mansoni 6 (3.6%); Taenia species 84 (50.3%); Ascaris lumbricoides 81 (48.5%) and hookworm 63 (37.7%). Overall, 46.7% of the children were malnourished, 39.5% stunted, 22.8% underweight and 11.4% exhibiting wasting/thinness. Mean values of anthropometric indices were generally lower in children with co-infection than those with single infection. We observed low level of schistosomiasis but high prevalence of intestinal helminthiasis and poor nutritional status that calls for inclusion of PSAC in control programs. Electronic supplementary material The online version of this article (10.1186/s13104-017-2973-2) contains supplementary material, which is available to authorized users.

Background Interventions are currently being used against ‘infectious diseases of poverty’, which remain highly debilitating and deadly in most endemic countries, especially malaria, schistosomiasis, echinococcosis and African sleeping sickness. However, major limitations of current ‘traditional’ methods for diagnosis are neither simple nor convenient for population surveillance, and showed low sensitivity and specificity. Access to novel technologies for the development of adequate and reliable tools are expressly needed. A collaborative project between African Network for Drugs and Diagnostics Innovation and partner institutions in Africa and China aims to screen suitable serological biomarkers for diagnostic pipelines against these ‘diseases of the poor’. Methods Parasite-specific exposed versus unexposed individuals were screened and sera or urine/stools were collected through case-control studies in China and African countries. Target genes/open reading frames were selected, then will be cloned and cell-free expressed, quantified and immuno-detected. Target antigens/epitopes will be probed and screened with sera from exposed or unexposed individuals using a high-throughput antigen screening platform as the study progresses. The specificity and sensitivity of highly immunoreactive biomarkers will be evaluated as well, using enzyme-linked immunosorbent assays or dipsticks. Discussion This roadmap explicitly unfolds the integrated operating procedures with focus on malaria and schistosomiasis, for the identification of suitable biomarkers that will aid the prioritization of diagnostics for population use. However, there is need to further validate any new diagnostic through comparison with standard methods in field deployable tests for each region. Our expectations for the future are to seek regulatory approval and promote the use of diagnostics in endemic areas. Electronic supplementary material The online version of this article (doi:10.1186/s40249-017-0344-9) contains supplementary material, which is available to authorized users.

Background The current trend of Plasmodium vivax cases imported from Southeast Asia into China has sharply increased recently, especially from the China–Myanmar border (CMB) area. High recombination rates of P. vivax populations associated with varied transmission intensity might cause distinct local selective pressures. The information on the genetic variability of P. vivax in this area is scant. Hence, this study assessed the genetic diversity of P. vivax genome sequence in CMB area and aimed to provide information on the positive selection of new gene loci. Results This study reports a genome-wide survey of P. vivax in CMB area, using blood samples from local patients to identify population-specific selective processes. The result showed that considerable genetic diversity and mean pair-wise divergence among the sequenced P. vivax isolates were higher in some important gene families. Using the standardized integrated haplotype score (|iHS|) for all SNPs in chromosomal regions with SNPs above the top 1% distribution, it was observed that the top score locus involved 356 genes and most of them are associated with red blood cell invasion and immune evasion. The XP-EHH test was also applied and some important genes associated with anti-malarial drug resistance were observed in high positive scores list. This result suggests that P. vivax in CMB area is facing more pressure to survive than any other region and this has led to the strong positive selection of genes that are associated with host-parasite interactions. Conclusions This study suggests that greater genetic diversity in P. vivax from CMB area and positive selection signals in invasion and drug resistance genes are consistent with the history of drug use during malaria elimination programme in CMB area. Furthermore, this result also demonstrates that haplotype-based detecting selection can assist the genome-wide methods to identify the determinants of P. vivax diversity. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1882-0) contains supplementary material, which is available to authorized users.

This cross-sectional study was undertaken to assess the status of school-based water, sanitation and hygiene (WASH) resources and soil-transmitted helminthiasis (STH) in Odeda, Ogun State, Nigeria. The status and condition of WASH resources were determined in eight selected schools (three with WASH support and five without). Stool samples were also collected from 428 pupils from both school categories and screened for STH infections. Findings showed that water and sanitation conditions of WASH resource programming schools were better than those in schools without WASH support. However, pupils’ knowledge about STH infections and basic hygiene were not significantly different between both categories of school (P > 0·05). The prevalence of Hookworm, Ascariasis and Trichuriasis cases recorded were 26·2, 18·2 and 1·6% respectively, with an overall prevalence of 33·4%. By school categories, Ascariasis (14·9 vs 20·6), Hookworm (17·7 vs 32·0), Trichuriasis (1·7 vs 1·6) and, any STH prevalence (27·4 vs 37·5) were recorded for schools with WASH resource programming and those without respectively. A greater portion of the infected children 95 (66·4%) were from schools without WASH support. Our findings imply that WASH resource may have very positive impact on the control of STH among school children. However, there is need for improvement on coverage, adequacy and maintenance of WASH facilities in school.

Background Oncomelania hupensis is the unique intermediate host of Schistosoma japonicum, which plays a crucial role in the transmission of schistosomiasis. The endemic area of S. japonicum is strictly consistent with the geographical distribution of O. hupensis. Methods A total of 24 populations of O. hupensis from four ecological landscapes were selected for analysis of genetic diversity by screening eight microsatellite DNA polymorphic loci. Results The number of alleles per locus ranged from 29 to 70 with an average of 45.625 and that of effective alleles were 18.5 to 45.8 with an average of 27.4. The observed (Ho) and expected (He) heterozygosities varied from 0.331 to 0.57 and from 0.888 to 0.974, respectively. The mean of polymorphism information content (PIC) for all populations was 0.940, appearing polymorphic for all loci. For the fixation index of F-Statistics, Fit and Fst were 54.95 and 37.62 %, respectively. Variation of O. hupensis chiefly exists among individuals, accounting for 60.58 % of the total variation determined by Analysis of Molecular Variation (AMOVA). Variation among individuals within populations, among populations within groups and among groups only accounted for 26.60, 8.04 and 4.78 %, respectively. This distribution of variation suggests that genetic differences principally originate from within-populations rather than among-populations. Moreover, UPGMA cluster analysis showed that the populations spreading within middle and lower reaches of the Yangtze River (HBWH, JSYZ, JXNC, HNHS, JXJJ, AHWW, HBJL, JXDC, HNNX, JSYZJZ, ZJJH, AHNG and AHWJ) clustered together first, then gathered with the populations in the high mountains (SCMS, SCYA, SCPJ, YNEY, SCLS, YNWS and SCXC), coastal hills (FJFQ and FJFZ) and Karst landform (GXBS and GXYZ) successively. Conclusion This study provides novel insight into the theoretical source of genetic differentiation of Oncomelania hupensis in mainland China, which is critical for the epidemiological investigation and surveillance of S. japonicum.

SUMMARYUntil recently, the epidemiology and control of schistosomiasis in sub-Saharan Africa have focused primarily on infections in school-aged children and to a lesser extent on adults. Now there is growing evidence and reports of infection in infants and pre-school-aged children (⩽6 years old) in Ghana, Kenya, Mali, Niger, Nigeria and Uganda, with reported prevalence from 14% to 86%. In this review, we provide available information on the epidemiology, transmission and control of schistosomiasis in this age group, generally not considered or included in national schistosomiasis control programmes that are being implemented in several sub-Saharan African countries. Contrary to previous assumptions, we show that schistosomiasis infection starts from early childhood in many endemic communities and factors associated with exposure of infants and pre-school-aged children to infection are yet to be determined. The development of morbidity early in childhood may contribute to long-term clinical impact and severity of schistosomiasis before they receive treatment. Consistently, these issues are overlooked in most schistosomiasis control programmes. It is, therefore, necessary to review current policy of schistosomiasis control programmes in sub-Saharan Africa to consider the treatment of infant and pre-school-aged children and the health education to mothers.

A cross-sectional study to determine malaria parasitemia amongst 300 randomly selected pregnant women attending government and private healthcare facilities in Rivers State was carried out. Blood samples were obtained through venous procedure and the presence or absence of Plasmodium was determined microscopically through thin and thick blood films. Socio-demographic information was obtained from questionnaires administered to the pregnant women enrolled. A total of 81 (27.0%) pregnant women were infected with P. falciparum. In private healthcare centres, 39 (26.0%) pregnant women were infected, while 42 (28.0%) were found infected in government hospital (x2= 0.101, df= 1, p>0.05). In the private healthcare centres, malaria prevalence among pregnant women in their first, second and third trimesters varied between 24.0-30.0% while in the government healthcare centre, malaria prevalence varied between 22.0%-30.0% (x2= 0.502, df= 2, p>0.05). In the private healthcare centres, malaria prevalence among primigravidae, secundigravidae and multigravidae varied between 22.0-28.0% while in the government healthcare centres, malaria prevalence varied between 23.0-32.0% (x2 = 0.084, df= 2, p>0.05). In the private healthcare centres, malaria prevalence among age groups 11-20, 21-30 and 31-40 varied between 17.0-29.0% while in the government healthcare centre, malaria prevalence varied between 26.0-29.0% (x2= 1.408, df= 2, p>0.05). There was no overall significant difference in malaria prevalence between the government and private healthcare facilities. Malaria is a public health burden especially amongst pregnant women, therefore adequate health education and proper control measures against malaria should be encouraged.Keywords: Prevalence; pregnancy; plasmodium; gestation; parity; age.

Background Despite significant, steady progress in schistosomiasis control in the People's Republic of China over the past 50 years, available data suggest that the disease has re-emerged with several outbreaks of acute infections in the early new century. In response, a new integrated strategy was introduced. Methods This retrospective study was conducted between Jan 2005 and Dec 2012, to explore the effectiveness of a new integrated control strategy that was implemented by the national control program since 2004. Results A total of 1,047 acute cases were recorded between 2005 and 2012, with an annual reduction in prevalence of 97.7%. The proportion of imported cases of schistosomiasis was higher in 2011 and 2012. Nine clusters of acute infections were detected by spatio-temporal analysis between June and November, indicating that the high risk areas located in the lake and marshland regions. Conclusion This study shows that the new integrated strategy has played a key role in reducing the morbidity of schistosomiasis in the People's Republic of China., Author Summary A retrospective study on the incidence of acute schistosomiasis in the People's Republic of China (P.R. China) was performed, in order to assess the new integrated control strategy that was implemented through the national control program from 2005 to 2012. The lake and marshland regions have been identified as high risk areas as shown by the nine spatio-temporal clusters that we found in the transmission period between June and November each year. When a total of 1,047 reported cases of acute schistosomiasis were analyzed, a reduction in prevalence of 97.7% between 2005 and 2012 was found. In contrast, imported cases of acute schistosomiasis increased between 2011 and 2012. These findings support the approach and effectiveness of the new integrated strategy in the reduction of schistosomiasis morbidity.

Vector snails of trematode parasites are important because of their role in the transmission of parasitic diseases. However, information on the diversity and distribution of snail hosts in Abeokuta area of Ogun State is scanty. Snails were collected from 31 water bodies including streams, rivers and dams on a monthly basis for six months. The snails were identified using shell morphology and examined for cercariae shedding. Collection sites were geo-referenced. Environmental data, Normalized Difference Vegetation Index (NDVI), Land Surface Temperature (LST), rainfall and Land cover corresponding to these locations were derived from Moderate resolution Imaging Spectroradiometer (MODIS). Binary logistic regression analysis was used to create spatial maps and predictive model map for snail species distribution. A total of 87 vector snails were collected; Lymnaea natalensis 65 (74.71%) and Indoplanor bisexutus 22 (25.29%).Nine out of 22 I. exutus collected shed microcercouscercariae. Infected I. exutus , intermediate snail host of Schistosoma nasale , a cattle schistosome was found in two sites. The logistic regression analysis using remotely-sensed environmental data showed that NDVI was the significant variable influencing I. exutus distribution (B = -8.460, Sig = 0.043). Geospatial distribution maps were created to show the distribution of each snail species and potential transmission sites. This study mapped the distribution of snail hosts, identified possible transmission sites and demonstrates the presence of snail hosts of certain parasites in Abeokuta area (Abeokuta South and Abeokuta North Local Government Areas), the distribution of these snail hosts should be monitored to prevent transmission of these pathogens to humans. Keywords: geospatial, vector snails, trematode, distribution, malacological

Background The acceleration of the control of soil-transmitted helminth (STH) infections in Nigeria, emphasizing preventive chemotherapy, has become imperative in light of the global fight against neglected tropical diseases. Predictive risk maps are an important tool to guide and support control activities. Methodology STH infection prevalence data were obtained from surveys carried out in 2011 using standard protocols. Data were geo-referenced and collated in a nationwide, geographic information system database. Bayesian geostatistical models with remotely sensed environmental covariates and variable selection procedures were utilized to predict the spatial distribution of STH infections in Nigeria. Principal Findings We found that hookworm, Ascaris lumbricoides, and Trichuris trichiura infections are endemic in 482 (86.8%), 305 (55.0%), and 55 (9.9%) locations, respectively. Hookworm and A. lumbricoides infection co-exist in 16 states, while the three species are co-endemic in 12 states. Overall, STHs are endemic in 20 of the 36 states of Nigeria, including the Federal Capital Territory of Abuja. The observed prevalence at endemic locations ranged from 1.7% to 51.7% for hookworm, from 1.6% to 77.8% for A. lumbricoides, and from 1.0% to 25.5% for T. trichiura. Model-based predictions ranged from 0.7% to 51.0% for hookworm, from 0.1% to 82.6% for A. lumbricoides, and from 0.0% to 18.5% for T. trichiura. Our models suggest that day land surface temperature and dense vegetation are important predictors of the spatial distribution of STH infection in Nigeria. In 2011, a total of 5.7 million (13.8%) school-aged children were predicted to be infected with STHs in Nigeria. Mass treatment at the local government area level for annual or bi-annual treatment of the school-aged population in Nigeria in 2011, based on World Health Organization prevalence thresholds, were estimated at 10.2 million tablets. Conclusions/Significance The predictive risk maps and estimated deworming needs presented here will be helpful for escalating the control and spatial targeting of interventions against STH infections in Nigeria., Author Summary Infections with three kinds of parasitic worms—hookworm, roundworm, and whipworm—are collectively known as soil-transmitted helminths (STHs). These parasitic worm infections are widespread in Nigeria, but the exact distribution is poorly understood. In view of the global commitment to control STH infections, there is a need to accelerate the mapping of STH infections to guide control interventions, such as large-scale administration of deworming drugs. In this study, we collated survey data from the year 2011 for Nigeria. The data were utilized to predict the distribution of STH infection based on environmental and socioeconomic covariates, and employing a Bayesian geostatistical modeling approach. Our results indicated that STH infections are widely distributed across Nigeria with prevalence estimates as high as 83% for roundworm, 50% for hookworm, and 19% for whipworm infections at specific survey locations. We predict that 5.7 million school-aged children were infected with STHs. The numbers of deworming tablets for annual or bi-annual treatment of the school-aged population at local government areas level in Nigeria for 2011 were estimated to be 10.2 million.

Background: Marching towards the elimination of schistosomiasis in China, both the incidence and prevalence have witnessed profound decline over the past decades, with the strategy shifting from morbidity control to transmission control. The current challenge is to find out hotspots of transmission risk for precise targeted control in low-prevalence areas. This study assessed the risk at the village level, using the spatial and temporal characteristics of Schistosomiasis japonica in Anhui province from 2006 to 2012. Method: The comprehensive database was generated from annual surveillance data at village level in Anhui province between 2006 and 2012, comprising schistosomiasis prevalence among humans and cattle, occurrence rate of infected environments and incidence rate of acute schistosomiasis. The database parameters were matched with geographic data of the study area and fine scale spatial-temporal cluster analysis based on retrospective space-time scan statistics was used to assess the clustering pattern of schistosomiasis. The analysis was conducted by using SaTScan 9.1.1 and ArcGIS 10.0. A spatial statistical modelling was carried out to determine the spatial dependency of prevalence of human infection by using Geoda 1.4.3. Result: A pronounced decline was found in the prevalence of human infection, cattle infection, occurrence rate of environment with infected vector snails and incidence rate of acute schistosomiasis from 2006 to 2012 by 48.6%, 71.5%, 91.9% and 96.4%, respectively. Meanwhile, all 4 indicators showed a statistically significant clustering pattern both in time and space, with a total of 16, 6, 8 and 4 corresponding clustering foci found respectively. However, the number of clustering foci declined with time, and none was found after year 2010. All clustering foci were mainly distributed along the Yangtze River and its connecting branches. The result shows that there is a direct spatial relationship between prevalence of human infection and the other indicators. Conclusion: A decreasing trend in space-time clustering of schistosomiasis endemic status was observed between 2006 and 2012 in Anhui province. Nevertheless, giving the complexity in schistosomiasis control, areas within the upper-stream of Yangtze River in Anhui section and its connecting branches should be targeted for effective implementation of control strategies in the future.

Background The number of pulmonary tuberculosis (PTB) cases in China ranks third in the world. A continuous increase in cases has recently been recorded in Zhaotong prefecture-level city, which is located in the northeastern part of Yunnan province. This study explored the space-time dynamics of PTB cases in Zhaotong to provide useful information that will help guide policymakers to formulate effective regional prevention and control strategies. Methods The data on PTB cases were extracted from the nationwide tuberculosis online registration system. Time series and spatial cluster analyses were applied to detect PTB temporal trends and spatial patterns at the town level between 2011 and 2015 in Zhaotong. Three indicators of PTB treatment registration history were used: initial treatment registration rate, re-treatment registration rate, and total PTB registration rate. Results Seasonal trends were detected with an apparent symptom onset peak during the winter season and a registration peak during the spring season. A most likely cluster and six secondary clusters were identified for the total PTB registration rate, one most likely cluster and five secondary clusters for the initial treatment registration rate, and one most likely cluster for the re-treatment registration rate. The most likely cluster of the three indicators had a similar spatial distribution and size in Zhenxiong County, which is characterised by a poor socio-economic level and the largest population in Yunnan. Conclusion This study identified temporal and spatial distribution of PTB in a high PTB burden area using existing health data. The results of the study provide useful information on the prevailing epidemiological situation of PTB in Zhaotong and could be used to develop strategies for more effective PTB control at the town level. The cluster that overlapped the three PTB indicators falls within the geographic areas where PTB control efforts should be prioritised.