Snail-borne parasitic diseases:an update on global epidemiological distribution,transmission interruption and control methods

Background:Snail-borne parasitic diseases,such as angiostrongyliasis,clonorchiasis,fascioliasis,fasciolopsiasis,opisthorchiasis,paragonimiasis and schistosomiasis,pose risks to human health and cause major socioeconomic problems in many tropical and sub-tropical countries.In this review we summarize the core roles of snails in the life cycles of the parasites they host,their clinical manifestations and disease distributions,as well as snail control methods.Main body:Snails have four roles in the life cycles of the parasites they host:as an intermediate host infected by the first-stage larvae,as the only intermediate host infected by miracidia,as the first intermediate host that ingests the parasite eggs are ingested,and as the first intermediate host penetrated by miracidia with or without the second intermediate host being an aquatic animal.Snail-borne parasitic diseases target many organs,such as the lungs,liver,biliary tract,intestines,brain and kidneys,leading to overactive immune responses,cancers,organ failure,infertility and even death.Developing countries in Africa,Asia and Latin America have the highest incidences of these diseases,while some endemic parasites have developed into worldwide epidemics through the global spread of snails.Physical,chemical and biological methods have been introduced to control the host snail populations to prevent disease.Conclusions:In this review,we summarize the roles of snails in the life cycles of the parasites they host,the worldwide distribution of parasite-transmitting snails,the epidemiology and pathogenesis of snail-transmitted parasitic diseases,and the existing snail control measures,which will contribute to further understanding the snail-parasite relationship and new strategies for controlling snail-borne parasitic diseases.

Countermeasures of Goat Parasitic Diseases in Xiangxi Tujia and Miao Autonomous Prefecture

Xiangxi Tujia and Miao Autonomous Prefecture is located in western Hunan province with abundant pastures,suitable for husbandry.However,parasitic diseases become an obstacle for goat industry development.In the research,based on parasite damages,epidemic variety and characters,some prevention measures were proposed,as follows：improving goat raising and management,rotation grazing,reinforcement of disinfection and quarantine,and regular parasite expelling,providing references for goat farming in Xiangxi.

Compounds from African Medicinal Plants with Activities Against Selected Parasitic Diseases:Schistosomiasis,Trypanosomiasis and Leishmaniasis

Parasitic diseases continue to represent a threat on a global scale,particularly among the poorest countries in the world.This is particularly because of the absence of vaccines,and in some cases,resistance against available drugs,currently being used for their treatment.In this review emphasis is laid on natural products and scaffolds from African medicinal plants(AMPs)for lead drug discovery and possible further development of drugs for the treatment of parasitic diseases.In the discussion,emphasis has been laid on alkaloids,terpenoids,quinones,flavonoids and narrower compound classes of compounds with micromolar range activities against Schistosoma,Trypanosoma and Leishmania species.In each subparagraph,emphasis is laid on the compound subclasses with most promising in vitro and/or in vivo activities of plant extracts and isolated compounds.Suggestions for future drug development from African medicinal plants have also been provided.This review covering 167 references,including 82 compounds,provides information published within two decades(1997-2017).

Foodborne parasitic diseases in China:A scoping review on current situation,epidemiological trends,prevention and control

Objective:Foodborne parasitic diseases,although with a declining overall incidence rate,are still endangering local public safety.This review aims to describe the current situation and epidemiological trends of foodborne parasitic diseases in China in order to explore possible reasons contributors to its high prevalence in some areas,and propose strategies for prevention and control accordingly.Methods:A scoping review was conducted by searching Pub Med,CNKI,Wanfang,CQVIP,Embase,and the Cochrane Library using search formula"foodborne parasitic diseases(or foodborne parasites)"AND"China".Studies on foodborne parasitic diseases in China were considered,but only articles in English or Chinese published between January 1980 and June 2020 were retrieved.Included studies were screened according to the eligibility criteria:1)diseases consistent with the WHO definition of foodborne parasitic diseases;2)the food carriers were included in the WHO food classification;3)data related to epidemiology,pathogenicity,and prevention and control;4)Foodborne parasitic diseases cases or outbreaks in China.Results:A total of 111 out of 665 records were included and summarized.The prevalence of clonorchiasis,angiostrongyliasis,echinococcosis,trichinellosis and cysticercosis was still increasing although the infection rate of soil-transmitted nematodes has substantially decreased in recent years.Diverse eating habits,close contact with animals,and urbanization were contributing factors to the increase.Conclusions:Foodborne parasitic diseases remain an important public health issue in China with the progress of economic globalization and food diversification.We should manage to raise public awareness about the prevention and control of foodborne parasitic diseases,improve health and safety inspections,as well as public health practice.

Effects of Parasitic Diseases on the Cardiovascular System

The parasitic disease can significantly affect the cardiovascular system through various mechanisms;even though it is traditionally regarded as a disease characterized by parasitic sites’ mechanical damage and some immune responses. Recent studies have shown that the role of parasitic factors in the cause of death due to cardiovascular events cannot be ignored. Considering the worldwide prevalence of parasitic diseases, exploring the effects of parasitic diseases on the cardiovascular system becomes increasingly essential. Here we summarize the latest understanding of common parasitic infections, explore the possible mechanisms of cardiovascular responses to parasitic infections, and propose feasible strategies for preventing and treating parasite-induced cardiac reactions.

INSTITUTE OF PARASITIC DISEASES CHINESE ACADEMY OF PREVENTIVE MEDICINE

The Institute of Parasitic Diseases was set up in 1950 in Nanjing and moved to the current location of Shanghai in 1957. Its precursor was the Huadong Branch of the National Institute of Health. It has around 350 staff and 8 departments, namely, Department of Epidemiology; Department of Parasite Biology; Department of Vector Biology and Control; Department of Diagnosis and Immunology; Department of Biochemistry; Department of Pharmaceutical Chemistry; Department of

MY CONTRIBUTION TO THE CONTROL OF PARASITIC DISEASES

The parasitic pest is omnipresent in the world providing there are biological communities existing. Almost everywhere on the earth,human health is constantly threatened by some parasites to a greater or lesser degree.In the same way,domestic animals and economic plants have always fallen prey to the scourge.leading to yield reductions.As parasitic diseases are chronic in progress,people often neglect them until they become fatal.China is a country with vast territory and diversity in the

INSTITUTE OF PARASITIC DISEASES CHINESE ACADEMY OF PREVENTIVE MEDICINE

The Institute of Parasitic Diseases was set up in 1950 in Nanjing and moved to the current location of Shanghai in 1957. Its precursor was the Huadong Branch of the National Institute of Health. It has around 350 staff and 8 departments, namely, Department of Epidemiology; Department of Parasite Biology; Department of Vector Biology and Control; Department of Diagnosis and Immunology; Department of Biochemistry; Department of Pharmaceutical Chemistry; Department of Pharmacology; Department of Scientific Information; and a Central Laboratory of Instrumentation. This Institute has been designated as a WHO Collaborating Center for Malaria, Schistosomiasis, and Filariasis.

Liver inflammatory pseudotumor or parasitic granuloma?

INTRODUCTION Liver pseudotumor is a very rare benign lesion.Since the first case reported by Pack and Baker in1953,only 40 cases had been reported up to 1996.The diagnostic challenge of hepatic inflammatorypseudotumor is emphasized by the fact that most ofthe reported cases were diagnosed by surgicalprocedures.Pathogenesis and etiology of

Demographic,socioeconomic and environmental changes affecting circulation of neglected tropical diseases in Egypt

Egypt has been plagued by many neglected tropical diseases since Pharaonic time.These diseases are Schistosomiasis.soil transmitted helminthiasis,lymphatic filariasis.leishmaniasis and fascioliasis beside the epidermal parasitic skin diseases.Indeed,theses disease still persist as public health problem in the country by the influence of demographic,socioeconomic and environmental obstacles.This study seeks for understanding the contribution of each factor in each obstacle in neglected tropical diseases perpetuation which in turn could help the governorate in planning integrated control strategies.It was found that poverty,unregulated urbanization and inadequate sanitation are important socioeconomic factors that have great effect on the transmission dynamics of the disease.The environmental factors which affect the epidemiology of these diseases in the counln are scarcity of water,construction of dams,land reclamation for agriculture beside the climate factors.Unfortunately.the panic increase in the population growth rale minimizes the efforts done by the governorate to elevate the public health services.These conditions also affect the transmission of epidermal parasitic skin diseases including scabies,head lice and hookworm—related cutaneous larva migrans.The control programs and the recommendations to combat the diseases were discussed.The present study showed that the ecological factors affecting each neglected tropical disease in Egypt are somewhat similar which makes it worthy to develop an integrated control approaches aiming at improving the leading factors of neglected tropical diseases circulation in the country.

Prevalence of Intestinal Parasites in Sickle Cell Disease Patients Attending Jos University Teaching Hospital, Nigeria

Several studies have shown that sickle cell disease (SCD) is made worse by infections;it was necessary to carry out this study to ascertain the occurrence of intestinal parasitic infections to the number of SCD patients infected compared to Non-SCD patients, the impact of the infections on Pack cell volume (PCV) of the SCD patients in Nigeria populace. A total of 140 stool samples were collected from both SCD patients and Non-SCD patients. 3 ml of venous blood, seventy samples in total were collected from the SCD patients only. The blood and stool samples were collected from September 2005 to November 2005;structured questionnaire was administered to each of the patient that gave consent to be part of the study alongside with questionnaire interview. The stool samples were analysed macroscopically and microscopically using saline, iodine and formal-ether concentration technique. The blood samples were analysed by micro-heamatocrit method. The findings showed that a total of six parasites were identified among the SCD patients and a total of thirteen parasites were identified among Non-SCD patients. Although the prevalence of intestinal parasitic infections was low among the research participates, the identified parasites fell into the 4 major categories of intestinal parasites, an indication that SCD patients can be susceptible to any of the intestinal worms/protozoa. Despite a low prevalence of intestinal parasites among the studied individual at the time of this study, it is however, necessary for regular laboratory investigations for intestinal worm/protozoa since they are still a public health problem.

Developments in the Diagnostic Techniques of Infectious Diseases: Rural and Urban Prospective

Objectives: Diagnostics is the first step for the treatment and eradication of infectious microbial diseases. Due to ever evolving pathogens and emerging new diseases, there is an urgent need to identify suitable diagnostic techniques for better management of each disease. The success rate of specific diagnostic technique in any population depends on various factors including type of the microbial pathogen, availability of resources, technical expertise, disease severity and degree of epidemic of disease in the area. One of the important tasks of the policy makers is to identify and implement suitable diagnostic techniques for specific regions based on their specific requirements. In this review we have discussed various techniques available in the literature and their suitability for the target population based on above mentioned criteria. Methods: Diagnostic techniques evaluation of well documented representative microbial diseases;Tuberculosis (bacterial), Malaria (parasitic) and HIV (viral) were included in the study. Identification and collection of information and data was performed focusing on the diagnostic techniques used from the scientific publications from Pubmed, Science Access, Scopus, EMBASE and several regional databases. WHO and CDC database for Tuberculosis, Malaria and HIV were also included. These techniques were compared with respect to the financial resource availability, expertise and management, functional capacity, pathogen virulence and degree of epidemic in the population. Results and Conclusion: In case of Tuberculosis, ELISA and colorimetric techniques are successful in rural and urban communities with 80% - 90% sensitivity. Genotyping and SNP analysis are useful in drug resistant strains. Parasitic disease Malaria also follows the same trend with diagnostic techniques like RDTs being common in both population with fast results and around 90% sensitivity. STD disease like HIV however shows slight different trends due to urgent need of interference in rural epidemics of the disease. Rapid and sensitive immunotechniques like dipsticks and agglutination with almost 100% sensitivity are used in both rural and urban areas. For the confirmation further tests are done like protein Western and NAAT. Advance techniques could be the option for higher epidemic area, drug resistance and disease research, while rapid techniques would be suitable for low income areas and POC facilities. Therefore, suitability of the diagnostic techniques for better management depends not only on the financial resources and assessment skills of a community but sometimes on the disease itself. We have further discussed the technological improvements for specific settings (rural/urban) based on the past research for better management of diseases, which could be implemented for the understanding of understudied and newly emerging diseases.

Self-Reported Prevalence and Socio-Demographic Determinants of Multiple Parasitic Infection among Schooling Adolescents in Nigeria

Background: Despite the rising burden of parasitic infections among young schooling adolescents in sub-Saharan Africa, insufficient attention has been paid to school-health. This study examined the self-reported prevalence of major parasitic infections and its association with key socio-demographic factors among young schooling adolescents in Southern Nigeria. Methods: An interviewer-administered school-based survey of students attending schools in Southern Nigeria was conducted in 2013. The study sample involved 585 students (60.9% male, 39.2% female and overall mean age of 15 years). The outcome variable was the self-reported presence of parasitic infection suffered within the past twelve months. The exposure variables were socio-demographic characteristics: age, sex, geolocality, school ownership, parents’ level of education and occupation. Association between the number of parasitic infections and socio-demographic factors were examined, and multivariate logistic regression was used to determine socio-demographic factors predictive of the presence of parasitic infections. Results: The most prevalent parasitic diseases reported across the sample were malaria (46.9%) and helminthiasis (27.7%). Over a quarter (38.5%) had one infectious disease, while about half (40.3%) reported had more than two infectious diseases. In the study sample, the number of parasitic diseases differed significantly by sex (p = 0.0344), age (p = 0.0483), geolocality (p = 0.0001), school ownership (p = 0.0012) and parents’ occupation (p = 0.0199). Multivariate logistic regression analysis showed that attending private school was negatively associated with the presence of parasitic diseases (β = ?0.9129, p = 0.0022). Conclusion: The high prevalence of multiple parasitic infections among the study population is worrisome and should be considered as a school-health concern. Concerted efforts are highly needed to develop school-health intervention programs for addressing the high prevalence of parasitic infection among students. Such programs should be tailored for specific socio-demographic groups. Although there was strong proportionality between self-reported symptoms and parasitic diseases reported, laboratory-based investigation is needed to validate our findings.

Malaria parasite carbonic anhydrase:inhibition of aromatic/heterocyclic sulfonamides and its therapeutic potential

Plasmodium falciparum(P.falciparum) is responsible for the majority of life-threatening cases of human malaria,causing 1.5-2.7 million annual deaths.The global emergence of drug-resistant malaria parasites necessitates identification and characterisation of novel drug targets and their potential inhibitors.We identified the carbonic anhydrase(CA) genes in P.falciparum.The pfGA gene encodes an α-carbonic anhydrase,a Zn^(2+)-metalloenzme,possessing catalytic properties distinct from that of the human host CA enzyme.The amino acid sequence of the pfCA enzyme is different from the analogous protozoan and human enzymes.A library of aromatic/heterocyclic sulfonamides possessing a large diversity of scaffolds were found to be very good inhibitors for the malarial enzyme at moderate-low micromolar and submicromolar inhibitions.The structure of the groups substituting the aromatic-ureido-or aromatic-azomethine fragment of the molecule and the length of the parent sulfonamide were critical parameters for the inhibitory properties of the sulfonamides.One derivative,that is,4-(3,4-dichlorophenylureido)thioureidobcnzcnesulfonamide(compound 10) was the most effective in vitro Plasmodium falciparum CA inhibitor,and was also the most effective antimalarial compound on the in vitro P.falciparum growth inhibition.The compound 10 was also effective in vivo antimalarial agent in mice infected with Plasmodium berghei,an animal model of drug testing for human malaria infection. It is therefore concluded that the sulphonamide inhibitors targeting the parasite CA may have potential for the development of novel therapies against human malaria.

Imported parasitic diseases in China's Mainland:current status and perspectives for better control and prevention

Background:The high prevalence of parasitic diseases leads to millions of deaths and disabilities each year in developing countries.China has also been greatly affected by parasitic infections,including filariasis,leishmaniasis,malaria,schistosomiasis,and soil-transmitted nematodosis.However,the situation in China improved dramatically after comprehensive parasitic disease control efforts were strengthened,leading to the elimination of filariasis in 2006 and to significant control over other diseases.However,imported parasitic disease cases are inevitable,and such cases have increasingly been reported as a result of enhanced globalization and international or regional cooperation.These imported diseases represent a major obstacle to the elimination of several parasitoses,such as malaria.Main text:This paper reviews imported cases of parasitic diseases in China's Mainland,particularly malaria and schistosomiasis,based on data reported separately by the Chinese annual reports and from other published papers.We summarize the new challenges that face parasitic disease control efforts in China's Mainland and perspectives regarding better control.We argue that both the provision of professional education and updated training for medical care personnel and the management and surveillance of people entering China are essential.We recommend that Chinese migrant workers should be considered a priority group for health education and that public awareness of imported diseases should be emphasized.Furthermore,we underscore the importance of investigating the distribution of introduced/potential vectors,parasite susceptibility,and improvements in diagnostic techniques and drug stocks.Conclusions:Imported cases have become the main challenge to the elimination of several parasitoses,such as malaria and schistosomiasis,in China's Mainland.China should act to meet these challenges,which are closely associated with national biological safety.

Major parasitic diseases of poverty in China's Mainland: perspectives for better contro

Significant progress has been made in the prevention,control,and elimination of human parasitic diseases in China in the past 60 years.However,parasitic diseases of poverty remain major causes of morbidity and mortality,and inflict enormous economic costs on societies.In this article,we review the prevalence rates,geographical distributions,epidemic characteristics,risk factors,and clinical manifestations of parasitic diseases of poverty listed in the first issue of the journal Infectious Diseases of Poverty on 25 October 2012.We also address the challenges facing control of parasitic diseases of poverty and provide suggestions for better control.

Investigation and Preventive Measures of Fish Parasites in Huaihua City

The losses caused by outbreaks of various diseases in aquaculture intensive farming are becoming more and more serious. Fish diseases have become one of the problems that constrain the healthy development of aquaculture. Among them,fish parasitic diseases have also caused some losses to the aquaculture industry. In this paper,17 species of fish parasites in Huaihua area,belonging to 15 genera in 13 families of 13 orders,are reviewed. In particular,the 10 kinds of fish parasitic diseases that are more harmful to farmed fishes are described in detail in order to provide a basis for the prevention of fish diseases in the future.

Eurytrematosis: An emerging and neglected disease in South Brazil

The trematodes of the genus Eurytrema are low pathogenic pancreatic parasites, but can be related to a decrease in cattle productive performance and eventually death. Parasitized animals develop chronic interstitial pancreatitis and may show a productive performance drop and emaciation. Human infection by Eurytrema sp. has already been reported in other countries as an incidental finding during autopsy or routine tests, but the parasite has not been found in humans in Brazil. However, it is possible that a large number of people could be infected, since parasitological tests have low sensitivity and the parasite is neglected as a pathogen for humans and even animals. Attempts to control and treat Eurytrematosis have generally presented low effectiveness. With the aim to control the disease and provide more information regarding its pathogenicity, our research group is developing a number of studies about Eurytrema spp. We hope to determine the damage in productivity, as well as, establish an efficient protocol for treatment and control of Eurytrematosis based on immunoprophylaxis and antiparasitical drug therapy.

Global output of research on epidermal parasitic skin diseases from 1967 to 2017

Background:Epidermal parasitic skin diseases(EPSD)occur in most countries and cause a considerable health and economic burden,particularly in the tropics and subtropics.The aim of this study was to assess and analyse peerreviewed literature on EPSD in humans.The results of this study serve as an indicator of the extent the scientific community,health authorities,and international health agencies interact with EPSD as a health problem that is commonly associated with poverty and poor hygiene.Methods:A bibliometric analysis methodology was used.The Scopus database was used to retrieve documents about EPSD for the study period(1967-2017).The study focused on scabies,tungiasis,pediculosis,hookwormrelated cutaneous larva migrans(HrCLM),myiasis,and cutaneous strongyloidiasis.Documents that specifically and explicitly discuss EPSD in animals,aquatic organisms,and birds were excluded.Results:In total,4186 documents were retrieved.A fluctuated growth of publications on EPSD in the past five decades was found.The retrieved documents received 43301 citations,an average of 10.3 citations per article and an h-index of 74.The keywords“scabies”and was the most commonly encountered keyword followed by the keywords“head lice”and“pediculosis”.The most active journal involved in publishing articles on EPSD was the International Journal of Dermatology(164;3.9%).Researchers from 93 different countries published the retrieved articles.The USA led with 735(17.6%)documents,followed by the UK(274;6.5%),and Germany(259;6.2%).In terms of institutions,the Charite-Universitätsmedizin Berlin in Germany was the most active in this field with 78(1.9%)publications,followed by the Universidade Federal do Cearáin Brazil with 52(1.2%)publications.Conclusions:Research on scabies and pediculosis dominated the field of EPSD research to the expense of tungiasis,HrCLM,myiasis,and cutaneous strongyloidiasis.There was an underrepresentation of literature from the tropics and subtropics despite EPSD being common in these areas.This could possibly be explained by the presence of limited number of non-English journals in the Scopus database.International research collaborations and research networking should be strengthened to help advance and prioritize research on EPSD.

Seventy years’ achievements of international cooperation by the National Institute of Parasitic Diseases at the Chinese Center for Disease Control and Prevention

Background: With the promotion of national control programs on parasitic and tropical diseases in China,the National Institute of Parasitic Diseases(NIPD),Chinese Center for Disease Control and Prevention has gained significant experience in the global health arena through international cooperation over the last seven decades allowing a multilateral impact in the elimination of major endemic diseases.Methods:: The achievements of NIPD since 1950 has been analyzed with emphasis on the various stages that started with research and control of the endemic parasitic and other tropical diseases at the national level and progressed via international cooperation into a global presence.Results: The major achievements contributed by NIPD consist of(i)improving technical capability;(ii)promoting control and elimination of parasitic and tropical diseases;(iii)participating in global health governance and cooperation;and(iv)developing a cooperation model for technical assistance and global public health development.It is expected that NIPD’s experience of international cooperation will be essential for the dissemination of China's successful experience in global health governance,emergency response and development,with focus on malaria and neglected tropical diseases such as schistosomiasis,soil-borne and food-borne helminthiases and echinococcosis.Conclusions: NIPD’s new tasks will not only continue to promote national control of endemic parasitic infections and disease elimination programs in China,but also play a leading role in global health and disease elimination programs in the future.