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.

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.

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.

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.

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.

Radical resection of hepatic polycystic echinococcosis complicated with hepatocellular carcinoma: A case report

BACKGROUND Hepatic cystic echinococcosis(CE)is an infectious zoonotic parasitic disease,and the insidious onset and slow progression of hepatic CE usually contributes to delayed diagnosis and treatment.Hepatocellular carcinoma(HCC)is the fourth most common malignant tumor.Co-existence of CE and HCC is fairly rare in clinical settings and the association between the two is still not well recognized.We report a case of hepatic CE complicated with HCC which are radically resected and raise some questions worth thinking about.CASE SUMMARY A 70-year-old man presented with upper abdominal pain.On admission,laboratory data showed that,except for hepatitis B surface antigen positivity,other indicators were normal,including alpha-fetoprotein.Computed tomography of the abdomen revealed a huge polycystic lesion in left liver lobe,without reinforcement after enhanced scanning and sized about 16.9 cm×12.2 cm,which was considered a type II hydatid cyst.Multiple small solid lesions were also found adjacent to it,and thus it was highly suspected as a malignant tumor.After a multidisciplinary team discussion,the diagnosis of co-occurrence of hepatic CE and HCC was made.According to Romic classification,the case belongs to type IIb,and radical left hemi-hepatectomy was performed.Postoperative pathological examination revealed CE co-existence with welldifferentiated HCC,consistent with the preoperative diagnosis.CONCLUSION With the combination of hepatitis B and obvious extrusion by large hydatid,the HCC risk of a patient might be higher.

Microbe/Bug-Busters Visit the Interactive House: An Itinerant Scenographic Device for Health Education

The term Ecology is derived from οἶκος (Greek “house” or environment), but our habitations usually overlooked in ecology or environmental studies. The expression “at home” usually means safety and comfort, but at home we are under risk of innumerous parasitic/microbial infections and contaminations/ envenomation. During the COVID-19 pandemic we were forced to stay at home, but the virus and other pathogens were also home-delivered. Education for health is highly effective in health promotion, particularly in poor areas. Thus, prophylactic interventions approaching household environment are required. The present activity aims community empowerment and engagement in controlling parasitic diseases and other infections such as Chagas disease, leishmaniasis, malaria, arboviruses etc. Inspired on the use of a house maket by Dr. Virgínia Schall to demonstrate Aedes mosquitoes breeding sites. We also employ house makets displaying pathogen vectors breeding/hiding sites. Although some makets can be opened, revealing intradomiciliary milieu, we intended to offer the public a literally “insider” view of this largely overlooked scenery. The “Interactive House”, also known as “House with no viruses and other bugs” is an educative, interactive, ludic device elaborated on an inflatable igloo, with furniture and utensils crafted using reused/recycled or low-cost materials. Live mosquito larvae were placed at peridomicile in water-accumulating plant pot saucer, leaves-clogged gutter, used tire, dog water bowl as well as within the domicile, in the shower drain trap. Evidengue®, crafted in cloth to block mosquito oviposition developed is presented. Participants enjoy taking part in the activity, seem amused, play, laugh and smile while enthusiastically take pictures. This educative activity permits health communication in a ludic interactive way, which may contribute to health promotion in areas with public health problems.

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.

Noninvasive diagnosis of periportal fibrosis in schistosomiasis mansoni:A comprehensive review

Schistosomiasis mansoni is a neglected disease and key public health problem,mainly due to its high prevalence,the scarcity of public policies,and the severity of some clinical forms.Periportal fibrosis(PPF)is the commonest complication of chronic schistosomiasis mansoni and its diagnosis requires different techniques.Even though wedge biopsy of the liver is considered the gold standard,it is not justified in non-surgical patients,and percutaneous liver biopsy may be informative but does not have sufficient sensitivity.Noninvasive PPF tests mostly include biological(serum biomarkers or combined scores)or physical assessments(imaging assessment of fibrosis pattern or tissue stiffness).Moreover,imaging techniques,such as ultrasound,computed tomography,magnetic resonance imaging,and elastography are applied not only to support the diagnosis of schistosomiasis,but also to assess and detect signs of portal hypertension and organ damage due to chronic schistosomiasis.A combination between a comprehensive history and physical examination with biomarkers for liver fibrosis and imaging methods seems to offer the best approach for evaluating these patients.In addition,understanding their strengths and limitations will allow a more accurate interpretation in the clinical context and can lead to greater accuracy in estimating the degree of fibrosis in patients with Schistosomiasis mansoni(S.mansoni)infection.This review will discuss the different noninvasive methods that are currently available for the evaluation of PPF in S.mansoni infection,and their application,advantages,and limitations in clinical practice.

Magnetic resonance imaging of eosinophilic meningoencephalitis caused by Angiostrongylus cantonensis following eating freshwater snails

Background Angiostrongyliasis cantonensis is a worldwide-existing parasitic disease. However, the relevant reports on its radiological appearances are limited. In this study, we investigated magnetic resonance imaging （MRI） features of eosinophilic meningoencephalitis in a group of consecutive patients caused by human infection with Angiostrongylus cantonensis after eating freshwater snails. Methods We performed brain MR imaging on 74 patients with angiostrongyliasis cantonensis. The scanner was a 0.5T unit. For each patient MR pulse sequences of $E Tl-weighted image （TlWl） and FSE T2-weighted image （T2Wl） were used. After intravenous administration of gadolinium chelate （Gd-DTPA） repeated Tl-weighted images were obtained. MRI features of the lesions in the brain and meninges were analyzed and recorded after observing initial and follow-up MR images. The classification of the types of angiostrongyliasis cantonensis infection was done on the basis of locations of the disorders. Results Forty-one （55%） normal and 33 （45%） abnormal MRI appearances in the brain were found. According to locations of the disorders, the types of angiostrongyliasis cantonensis infection were determined as follows： seventeen cases of type meningitis, three of type myeloencephalitis, one of type neuritis and twelve of mixed type （eight of type ventriculitis and five of type pneumonitis were among them）. In type meningitis, abnormal leptomeningeal enhancement was visualized. In type myeloencephalitis, lesions in the brain parenchyma may have iso- or slightly low signal intensity on TlWl and high signal intensity on T2Wl. Enhanced nodules in various shapes were shown on gadolinium-enhanced TlWl, a few lesions appeared as crescent enhancements and some lesions did not reveal abnormal enhancement. Other than brain lesions, an enhanced nodule was seen in the cervical spinal cord in one patient. In type ventriculitis, brain ventricular enlargement was demonstrated. In type neuritis, a nodule and abnormal enhancement in the right optic nerve was revealed. In type pneumonitis, patchy ground-glass opacity and consolidative lesions at the periphery of the lungs were seen. Follow-up results indicated that most lesions in the brain could resolve in 2 to 8 weeks. Conclusions Angiostrongyliasis cantonensis presented as both single type and mixed type. Nodular enhancing lesions in the brain and/or linear enhancement in the leptomeninges were the main findings, while crescent enhancement would be the characteristic sign of the disease on gadolinium-enhanced TlWI. Focal edematous changes without contrast enhancement in the brain could be seen on MRI in some cases.

Parasitology should not be abandoned:data from outpatient parasitological testing in Guangdong,China

Over the past six decades,the Chinese government made parasitoses with a high disease burden,including soiltransmitted nematode infections,malaria,leishmaniasis,filariasis,and schistosomiasis,a public health priority because they were seen to be crucial impediments to the development of rural areas.As a result,these debilitating parasitic diseases that used to be widely prevalent have been well controlled or eliminated.Consequently,less attention has been paid to parasitic infection during the rapid development of the economy,especially in developed areas.However,our investigations conducted in the parasitological laboratory of Sun Yat-sen University(Guangzhou,Guangdong,China)show that emerging parasitic diseases still threaten many people’s health,with 340 of 880 outpatients(38.6%)receiving a diagnosis of parasitic disease,among whom 201(59.1%)had clonorchiasis and 120(35.3%)had taeniasis/cysticercosis.Furthermore,our doctors are not equipped with sufficient parasitology knowledge because this discipline is not able to maintain attraction.Many parasitic infections that result in severe consequences are treatable and preventable,but the phenomena of misdiagnosis and missed diagnosis are common and merit attention.

The epidemiological models of Karl-Peter Hadeler

The most frequently cited articles out of KP Hadeler's 45 papers with epidemiological applications are summarized.Parasitic diseases which increase the death rate of the hosts proportional to the integer number of parasites present were described by integral equations for the generating function of the age-and time-dependent number of parasites.A model was derived for a population structured by the continuous level of parasitic infection.Stimulated by the spread of AIDS a new class of epidemic models was developed which take into account explicitly the formation and separation of pairs.For predator-prey populations with parasitic infections threshold conditions for the persistence of the predator were derived.The interaction of epidemics and demography was analysed.Several epidemiological conditions led to backward bifurcations associated with multiple infective stationary states.

Ecological significance and risks of mineral licks to mammals in a nature reserve on the Eastern Qinghai-Tibet Plateau

Mineral licks are important components of terrestrial ecosystems that have special value to the maintenance of fluid balance of mammals,by providing them with essential mineral nutrients such as sodium,calcium,and magnesium.In the Anzihe Nature Reserve,southwest China,seven species of ungulates and one species of primates were frequently observed visiting the mineral licks in high densities.As a consequence,mineral licks have attracted illegal hunters and facilitated the spread of parasites and diseases,leading to a depletion of local populations.Therefore,we suggest that regions with abundant mineral licks should be designated as key protected areas in the Anzihe Nature Reserve and relevant zones for animal health surveillance.