Towards global control of parasitic diseases in the Covid-19 era: One Health and the future of multisectoral global health governance

One World, One Health: Zoonotic Diseases, Parasitic Diseases, and Infectious Diseases

When we take into account how the boundaries between human, animal, and environmental health are inextricably linked and increasingly intertwined, it comes as no surprise that the One Health approach has assumed an unprecedented level of importance over the past decade [...].

Development of the WeChat Public Account I Love Parasitology and its Preliminary Application in the Teaching of Human Parasitology

OBJECTIVE

To better construct teaching resources, enhance real-time interaction and feedback between teachers and students in and out of class, and improve the teaching quality of parasitology, our team set up a WeChat public account I love Parasitology.

METHODS

The data sources were mainly from original pictures and multimedia materials of different parasites collected and produced by our team, as well as related materials collected from traditional publications and digital media. With the instant interactive platform, course schedules and corresponding teaching contents were sent by push notifications, case-based learning was carried out, and 2-way communication between students and teachers was achieved. Teaching effectiveness was assessed using a self-evaluation questionnaire.

RESULTS

A WeChat public account suitable for our daily teaching of parasitology was established. The second recursion and implementation of the learning resources allowed students to conduct in-depth reading and get unrestricted access to high-quality resources through the public account. In addition, all contents were in digital forms and made the original resources reborn, which would make up for our current and future shortage of physical teaching specimens. Moreover, the results from the questionnaire indicated that all these actions encouraged students to master theoretical knowledge, improved their abilities of case analysis and communication, and increased their knowledge of academic progress.

CONCLUSION

Our WeChat public account can provide excellent learning materials for students and is a good supplement to the routine education of human parasitology.

Enhancing Giardicidal Activity and Aqueous Solubility through the Development of "RetroABZ", a Regioisomer of Albendazole: In Vitro, In Vivo, and In Silico Studies

Parasitic diseases, including giardiasis caused by Giardia lamblia (G. lamblia), present a considerable global health burden. The limited effectiveness and adverse effects of current treatment options underscore the necessity for novel therapeutic compounds. In this study, we employed a rational design strategy to synthesize retroalbendazole (RetroABZ), aiming to address the limitations associated with albendazole, a commonly used drug for giardiasis treatment. RetroABZ exhibited enhanced in vitro activity against G. lamblia trophozoites, demonstrating nanomolar potency (IC50 = 83 nM), outperforming albendazole (189 nM). Moreover, our in vivo murine model of giardiasis displayed a strong correlation, supporting the efficacy of RetroABZ, which exhibited an eleven-fold increase in potency compared to albendazole, with median effective dose (ED50) values of 5 µg/kg and 55 µg/kg, respectively. A notable finding was RetroABZ's significantly improved water solubility (245.74 µg/mL), representing a 23-fold increase compared to albendazole, thereby offering potential opportunities for developing derivatives that effectively target invasive parasites. The molecular docking study revealed that RetroABZ displays an interaction profile with tubulin similar to albendazole, forming hydrogen bonds with Glu198 and Cys236 of the β-tubulin. Additionally, molecular dynamics studies demonstrated that RetroABZ has a greater number of hydrophobic interactions with the binding site in the β-tubulin, due to the orientation of the propylthio substituent. Consequently, RetroABZ exhibited a higher affinity compared to albendazole. Overall, our findings underscore RetroABZ's potential as a promising therapeutic candidate not only for giardiasis but also for other parasitic diseases.

Malaria epidemiological characteristics and control in Guangzhou, China, 1950-2022

BACKGROUND

Malaria was once widespread in Guangzhou, China. However, a series of control measures have succeeded in eliminating local malaria infections. Based on the analysis of the characteristics of malaria epidemics in Guangzhou, China, from 1950 to 2022, the changes and effectiveness of malaria control strategies and surveillance management in Guangzhou from 1950 to 2022 are described.

METHODS

Data on malaria prevention and treatment in Guangzhou from 1950 to 2022 were collected, and descriptive epidemiological methods were used to analyse the prevalence of malaria, preventive and control measures taken, and the effectiveness of prevention and treatment in different periods. Data on malaria cases were obtained from the Guangzhou Centre for Disease Control and Prevention (CDC) and the China Communicable Disease Reporting System.

RESULTS

The development of the malaria control system in Guangzhou has gone through four periods: 1. High malaria prevalence (1950-1979), 2. Intensive prevention and control stage (1980-2000), 3. Consolidating gains in malaria control (2001-2008), and 4. Preventing reestablishment of transmission (2009-2022). During Period 1, only medical institutions at all levels and the local CDCs, the Guangzhou CDC participated in the malaria prevention and control system, establishing a three-tier health system on malaria prevention and control. During Period 2, other types of organizations, including the agricultural sector, schools and village committees, the construction department and street committee, are involved in the malaria control system. During Period 3, more and more organizations are joining forces to prevent and control malaria. A well-established multisectoral malaria control mechanism and an improved post-elimination surveillance management system are in place. Between 1950 and 2022, a total of 420,670 cases of malaria were reported. During Period 1, there was an epidemic of malaria in the early 1950s, with an annual incidence rate of more than 10,000/100,000, including a high rate of 2887.98/100,000 in 1954. In Period 2 malaria was gradually brought under control, with the average annual malaria incidence rate dropping to 3.14/100,000. During Period 3, the incidence rate was kept below 1/100,000, and by 2009 local malaria infections were eliminated.

CONCLUSION

For decades, Guangzhou has adopted different malaria control strategies and measures at different epidemic stages. Increased collaboration among civil organizations in Guangzhou in malaria control has led to a significant decline in the number of malaria cases and the elimination of indigenous malaria infections by 2009.The experience of Guangzhou can guide the development of malaria control strategies in other cities experiencing similar malaria epidemics.

Real-time impact of COVID-19 pandemic on cutaneous leishmaniasis case finding and strategic planning, preventive interventions, control and epidemiology in a region with a high burden of cutaneous leishmaniasis and COVID-19: A cross-sectional descriptive study based on registry data in Ilam-Iran

Background and Aims

Cutaneous leishmaniasis (CL) is a severe parasitic disease affecting people, mostly in underdeveloped nations. As a zoonotic infection yearly incidence of CL depends on several parameters such as demographic, epidemiological, and environmental factors as well as prevention and control measures. The sudden outbreak of pandemics such as SARS-Corona-Virus-2 pandemic, can probably affect the incidence or reporting of other diseases, especially infectious diseases, in various ways such as pressure on health systems, providing sanitary services and its components, lockdowns and changes in people's living habits.

Aim

This study aimed to evaluate the COVID-19 impact on the incidence and other epidemiological aspects as well as control measures of CL in Ilam Province-Iran.

Methods

Required data was extracted from the CL registration system in Ilam from 2014 to 2021 to demonstrate the trend of CL incidence before and after COVID-19 pandemic.

Results

Based on our results, a declining pattern of CL incidence was observed, accompanied by the advent and intensification of the viral pandemic in Iran and Ilam province. Although, this decreasing pattern was not integral in all areas, and even increase in CL detection was emphasized in some regions.

Conclusion

It may be inferred that the COVID-19 pandemic may disrupt treatment programs of CL cases, rodent nest destruction, and fighting vector insects.

Schistosoma and Leishmania: An Untold Story of Coinfection

A remarkable characteristic of infectious diseases classified as Neglected Tropical Diseases (NTDs) is the fact that they are mostly transmitted in tropical and subtropical regions with poor conditions of sanitation and low access to healthcare, which makes transmission areas more likely to overlap. Two of the most important NTDs, schistosomiasis and leishmaniasis, despite being caused by very different etiological agents, have their pathogenesis heavily associated with immune-mediated mechanisms, and Schistosoma spp. and Leishmania spp. have been shown to simultaneously infect humans. Still, the consequences of Schistosoma-Leishmania coinfections remain underexplored. As the inflammatory processes elicited by each one of these parasites can influence the other, several changes have been observed due to this coinfection in naturally infected humans, experimental models, and in vitro cell assays, including modifications in susceptibility to infection, pathogenesis, prognostic, and response to treatment. Herein, we review the current knowledge in Schistosoma-Leishmania coinfections in both human populations and experimental models, with special regard to how schistosomiasis affects tegumentary leishmaniasis, discuss future perspectives, and suggest a few steps to further improve our understanding in this model of parasite-host-parasite interaction.

Toward One Health: a spatial indicator system to model the facilitation of the spread of zoonotic diseases

Recurrent outbreaks of zoonotic infectious diseases highlight the importance of considering the interconnections between human, animal, and environmental health in disease prevention and control. This has given rise to the concept of One Health, which recognizes the interconnectedness of between human and animal health within their ecosystems. As a contribution to the One Health approach, this study aims to develop an indicator system to model the facilitation of the spread of zoonotic diseases. Initially, a literature review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement to identify relevant indicators related to One Health. The selected indicators focused on demographics, socioeconomic aspects, interactions between animal and human populations and water bodies, as well as environmental conditions related to air quality and climate. These indicators were characterized using values obtained from the literature or calculated through distance analysis, geoprocessing tasks, and other methods. Subsequently, Multi-Criteria Decision-Making (MCDM) techniques, specifically the Entropy and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) methods, were utilized to combine the indicators and create a composite metric for assessing the spread of zoonotic diseases. The final indicators selected were then tested against recorded zoonoses in the Valencian Community (Spain) for 2021, and a strong positive correlation was identified. Therefore, the proposed indicator system can be valuable in guiding the development of planning strategies that align with the One Health principles. Based on the results achieved, such strategies may prioritize the preservation of natural landscape features to mitigate habitat encroachment, protect land and water resources, and attenuate extreme atmospheric conditions.

Impact of the COVID-19 pandemic on the actions of the Schistosomiasis Control Program in an endemic area in Northeastern Brazil

Schistosomiasis remains a serious public health concern in Brazil and the Schistosomiasis Control Program (PCE) was elaborated to assist in the control of the disease. Nevertheless, the irruption of the COVID-19 pandemic may have impacted the program. Herein, we assessed the impact of the pandemic on PCE actions in an endemic area in the region with the highest positivity rate for schistosomiasis in Brazil. We conducted an ecological, population-based study using data from the PCE of the state of Alagoas, between 2015 and 2021, to calculate the percentage of change. The temporal trend analysis was performed using the segmented log-linear regression model. To evaluate the spatial distribution of the data, choropleth maps were made showing the values of the% of change. Moran maps was elaborated to indicate the critical areas. Our analysis showed a decrease in the population surveyed in 2020 (-41.00%) and 2021 (-18.42%). Likewise, there was a reduction in the number of Kato-Katz tests performed (2020 = -43.45%; and in 2021 = -19.63%) and, consequently, a drop in the rate of positive tests (-37.98% in 2020 and -26.14% in 2021). Importantly, treatment of positive cases was lower than 80% (77.44% in 2020 and 77.38% in 2021). Additionally, spatial clusters with negative percentage values of up to -100% of the PCE indicators were identified mostly in the municipalities of the coastal areas that are historically most affected by schistosomiasis. Taken together, our analyzes corroborate that PCE actions in endemic municipalities of Alagoas were impacted by the COVID-19 pandemic.

Food- and vector-borne parasitic zoonoses: Global burden and impacts

Around 25% of the global population suffer from one or more parasitic infections, of which food- and vector-borne parasitic zoonotic diseases are a major concern. Additionally, zoonoses and communicable diseases, common to man and animals, are drawing increased attention worldwide. Significant changes in climatic conditions, cropping pattern, demography, food habits, increasing international travel, marketing and trade, deforestation, and urbanization play vital roles in the emergence and re-emergence of parasitic zoonoses. Although it is likely to be underestimated, the collective burden of food- and vector-borne parasitic diseases accounts for ∼60 million disability-adjusted life years (DALYs). Out of 20 neglected tropical diseases (NTDs) listed by the World Health Organization (WHO) and the Centres for Disease Control and Prevention (CDC), 13 diseases are of parasitic origin. There are about 200 zoonotic diseases of which the WHO listed eight as neglected zoonotic diseases (NZDs) in the year 2013. Out of these eight NZDs, four diseases, namely cysticercosis, hydatidosis, leishmaniasis, and trypanosomiasis, are caused by parasites. In this review, we discuss the global burden and impacts of food- and vector-borne zoonotic parasitic diseases.

A retrospective analysis of schistosomiasis related literature from 2011-2020: Focusing on the next decade

BACKGROUND

Schistosomiasis, an ancient and neglected tropical disease, which poses a huge threat to over 200 million people globally. It is necessary to have a general summary of schistosomiasis research after the new roadmap 2021-2030 issued by WHO. This study analyzes the current status of schistosomiasis research from the perspective of the One Health concept by analyzing important research literature published from 2011 to 2020, while further highlighting research priorities, difficulties, and research directions in order to propose suggestions for tropical disease studies research.

METHODS

Published literature related to schistosomiasis was searched from the Web of Science Core Collection (WoSCC) database. Focusing on a visual analysis of the main research literature in the field of schistosomiasis, CiteSpace software was used to conduct co-occurrence analysis with keywords, countries, institutions, and authors. Moreover, clustering and burst analyses of keywords and co-citation analysis of authors, publications, and journals were performed.

RESULTS

A total of 6638 schistosomiasis-related articles were published from 2011 to 2020, all of which can be sourced from the WoSCC database. The publication of schistosomiasis research has remained stable over the past 10 years, and contains studies in the area of human epidemiology, animal surveillance and the environment. The top five high-frequency keywords included Schistosoma mansoni, schistosomiasis, infection, praziquantel, and Schistosoma japonicum. The keywords formed nine clusters, including praziquantel, epidemiology, Schistosoma japonicum, helminths, protein, diagnosis, schistosomiasis, response, and haematobium. In recent years, most research studies focused on the mechanism of liver fibrosis, eliminating schistosomiasis, controlling risk factors, and the relationship between schistosomiasis infection and host immunity. The most productive countries include the United States, China, and Brazil, and the most productive institutions are the University of Basel, the Swiss Tropical and Public Health Institute, and the University of São Paulo. Highly productive authors include Jürg Utzinger and Donald P. McManus. At the time of writing, the author with the highest co-citation frequency (993 times) was Peter Hotez, and the journal with the highest co-citation frequency (3,720 times) was PLoS Neglected Tropical Diseases. Human schistosomiasis, published by Colley et al. (2014), was the most frequently co-cited publication (494 times).

CONCLUSIONS

This study provides a preliminary description of the current status of schistosomiasis research and an initial exploration of future research directions. The One Health concept was applied in the field of schistosomiasis control, as confirmed by this bibliometric analysis. Our study provides guidance for the development of research on schistosomiasis and other neglected tropical diseases.

Tuberculosis, HIV/AIDS and Malaria Health Services in sub-Saharan Africa - A Situation Analysis of the Disruptions and Impact of the COVID-19 Pandemic

BACKGROUND

The unprecedented and ongoing COVID-19 pandemic has exposed weaknesses in African countries' health systems. The impact of shifted focus on COVID-19 for the past 2 years on routine health services, especially those for the epidemics of Tuberculosis, HIV/AIDS and Malaria, have been dramatic in both quantity and quality.

METHODS

In this article, we reflect on the COVID-19 related disruptions on the Tuberculosis, HIV/AIDS and Malaria routine health services across Africa.

RESULTS

The COVID-19 pandemic resulted in disruptions of routine health services and diversion of already limited available resources in sub-Saharan Africa. As a result, disease programs like TB, malaria and HIV have recorded gaps in prevention and treatment with the prospects of reversing gains made towards meeting global targets. The extent of the disruption is yet to be fully quantified at country level as most data available is from modelling estimates before and during the pandemic.

CONCLUSIONS

Accurate country-level data is required to convince donors and governments to invest more into revamping these health services and help prepare for managing future pandemics without disruption of routine services. Increasing government expenditure on health is a critical part of Africa's economic policy. Strengthening health systems at various levels to overcome the negative impacts of COVID-19, and preparing for future epidemics will require strong visionary political leadership. Innovations in service delivery and technological adaptations are required as countries aim to limit disruptions to routine services.

The microscopic five of the big five: Managing zoonotic diseases within and beyond African wildlife protected areas

African protected areas strive to conserve the continent's great biodiversity with a targeted focus on the flagship 'Big Five' megafauna. Though often not considered, this biodiversity protection also extends to the lesser-known microbes and parasites that are maintained in these diverse ecosystems, often in a silent and endemically stable state. Climate and anthropogenic change, and associated diversity loss, however, are altering these dynamics leading to shifts in ecological interactions and pathogen spill over into new niches and hosts. As many African protected areas are bordered by game and livestock farms, as well as villages, they provide an ideal study system to assess infection dynamics at the human-livestock-wildlife interface. Here we review five zoonotic, multi-host diseases (bovine tuberculosis, brucellosis, Rift Valley fever, schistosomiasis and cryptosporidiosis)-the 'Microscopic Five'-and discuss the biotic and abiotic drivers of parasite transmission using the iconic Kruger National Park, South Africa, as a case study. We identify knowledge gaps regarding the impact of the 'Microscopic Five' on wildlife within parks and highlight the need for more empirical data, particularly for neglected (schistosomiasis) and newly emerging (cryptosporidiosis) diseases, as well as zoonotic disease risk from the rising bush meat trade and game farm industry. As protected areas strive to become further embedded in the socio-economic systems that surround them, providing benefits to local communities, One Health approaches can help maintain the ecological integrity of ecosystems, while protecting local communities and economies from the negative impacts of disease.

Public Health Policy Pillars for the Sustainable Elimination of Zoonotic Schistosomiasis

Schistosomiasis is a parasitic disease acquired through contact with contaminated freshwater. The definitive hosts are terrestrial mammals, including humans, with some Schistosoma species crossing the animal-human boundary through zoonotic transmission. An estimated 12 million people live at risk of zoonotic schistosomiasis caused by Schistosoma japonicum and Schistosoma mekongi, largely in the World Health Organization’s Western Pacific Region and in Indonesia. Mathematical models have played a vital role in our understanding of the biology, transmission, and impact of intervention strategies, however, these have mostly focused on non-zoonotic Schistosoma species. Whilst these non-zoonotic-based models capture some aspects of zoonotic schistosomiasis transmission dynamics, the commonly-used frameworks are yet to adequately capture the complex epi-ecology of multi-host zoonotic transmission. However, overcoming these knowledge gaps goes beyond transmission dynamics modelling. To improve model utility and enhance zoonotic schistosomiasis control programmes, we highlight three pillars that we believe are vital to sustainable interventions at the implementation (community) and policy-level, and discuss the pillars in the context of a One-Health approach, recognising the interconnection between humans, animals and their shared environment. These pillars are: (1) human and animal epi-ecological understanding; (2) economic considerations (such as treatment costs and animal losses); and (3) sociological understanding, including inter- and intra-human and animal interactions. These pillars must be built on a strong foundation of trust, support and commitment of stakeholders and involved institutions.