More medicines alone cannot ensure the treatment of neglected tropical diseases

Prevalence of depressive symptoms in patients with advanced schistosomiasis in China: A systematic review and meta-analysis

BACKGROUND

Advanced schistosomiasis is the most serious outcome of infection and has a negative impact on both physical fitness and mental health of patients, the latter of which has long been overlooked. Therefore, we performed this systematic review and meta-analysis to estimate the overall prevalence of depressive symptoms, one of the most common mental problems, in patients with advanced schistosomiasis in China.

METHODS

Six electronic databases were searched for studies reporting the prevalence of depressive symptoms in the targeted patients. Assessments were pooled using a fixed- or random-effects model based on heterogeneity test. Subgroup analyses were further performed and differences between/among groups were examined using the chi-squared test. The protocol had previously been registered in PROSPERO (CRD42023406708).

RESULTS

A total of 11 studies with 1,673 participants were included. The pooled prevalence of depressive symptoms in advanced schistosomiasis in China was 62.01% (95% CI: 51.30% - 72.72%), with a significant heterogeneity among studies. Depressive symptoms were more prevalent in patients with complications and more than half of the patients suffered a mild- or moderate-level of depression. No publication bias was found, and sensitivity analysis showed a stable result.

CONCLUSIONS

The overall prevalence of depressive symptoms in advanced schistosomiasis in China was high enough to warrant psychotherapeutic interventions, especially for patients with complications. This would greatly prevent or/and reduce depression and improve their quality of life.

Awareness and knowledge of female genital schistosomiasis in a population with high endemicity: a cross-sectional study in Madagascar

Introduction

Female genital schistosomiasis (FGS) is a neglected disease with long-term physical and psychosocial consequences, affecting approximately 50 million women worldwide and generally representing an unmet medical need on a global scale. FGS is the chronic manifestation of a persistent infection with Schistosoma haematobium. FGS services are not routinely offered in endemic settings with a small percentage of women at risk receiving adequate care. Madagascar has over 60% prevalence of FGS and no guidelines for the management of the disease. This study aimed to determine FGS knowledge among women and health care workers (HCWs) in a highly endemic area of Madagascar.

Methods

A convenience sampling strategy was used for this cross-sectional study. Descriptive statistics including proportions and 95% confidence intervals (CI) were calculated, reporting socio-demographic characteristics of the population. Knowledge sources were evaluated descriptively. Binary Poisson regression with robust standard errors was performed; crude (CPR) and adjusted prevalence ratio (APR) with 95% CIs were calculated.

Results

A total of 783 participants were included in the study. Among women, 11.3% (n = 78) were aware of FGS while among the HCWs 53.8% (n = 50) were aware of FGS. The highest level of knowledge was observed among women in an urban setting [24%, (n = 31)] and among those with a university education/vocational training [23% (n = 13)]. A lower APR of FGS knowledge was observed in peri-urban [APR 0.25 (95% CI: 0.15; 0.45)] and rural [APR 0.37 (95% CI 0.22; 0.63)] settings in comparison to the urban setting. Most HCWs reported other HCWs [40% (n = 20)] while women mainly reported their family [32% (n = 25)] as being their main source of information in the 6 months prior to the survey.

Discussion and conclusions

Our study shows limited awareness and knowledge of FGS among population groups in the highly endemic Boeny region of Madagascar. With this study we contribute to identifying an important health gap in Madagascar, which relates to a disease that can silently affect millions of women worldwide. In alignment with the targets of the NTD roadmap, addressing schistosomiasis requires a paradigm shift for its control and management including a greater focus on chronic forms of the disease.

A positive consequence of the COVID-19 pandemic: how the counterfactual experience of school closures is accelerating a multisectoral response to the treatment of neglected tropical diseases

Global access to deworming treatment is one of the public health success stories of low-income countries in the twenty-first century. Parasitic worm infections are among the most ubiquitous chronic infections of humans, and early success with mass treatment programmes for these infections was the key catalyst for the neglected tropical disease (NTD) agenda. Since the launch of the 'London Declaration' in 2012, school-based deworming programmes have become the world's largest public health interventions. WHO estimates that by 2020, some 3.3 billion school-based drug treatments had been delivered. The success of this approach was brought to a dramatic halt in April 2020 when schools were closed worldwide in response to the COVID-19 pandemic. These closures immediately excluded 1.5 billion children not only from access to education but also from all school-based health services, including deworming. WHO Pulse surveys in 2021 identified NTD treatment as among the most negatively affected health interventions worldwide, second only to mental health interventions. In reaction, governments created a global Coalition with the twin aims of reopening schools and of rebuilding more resilient school-based health systems. Today, some 86 countries, comprising more than half the world's population, are delivering on this response, and school-based coverage of some key school-based programmes exceeds those from January 2020. This paper explores how science, and a combination of new policy and epidemiological perspectives that began in the 1980s, led to the exceptional growth in school-based NTD programmes after 2012, and are again driving new momentum in response to the COVID-19 pandemic. This article is part of the theme issue 'Challenges and opportunities in the fight against neglected tropical diseases: a decade from the London Declaration on NTDs'.

Modelling morbidity for neglected tropical diseases: the long and winding road from cumulative exposure to long-term pathology

Reducing the morbidities caused by neglected tropical diseases (NTDs) is a central aim of ongoing disease control programmes. The broad spectrum of pathogens under the umbrella of NTDs lead to a range of negative health outcomes, from malnutrition and anaemia to organ failure, blindness and carcinogenesis. For some NTDs, the most severe clinical manifestations develop over many years of chronic or repeated infection. For these diseases, the association between infection and risk of long-term pathology is generally complex, and the impact of multiple interacting factors, such as age, co-morbidities and host immune response, is often poorly quantified. Mathematical modelling has been used for many years to gain insights into the complex processes underlying the transmission dynamics of infectious diseases; however, long-term morbidities associated with chronic or cumulative exposure are generally not incorporated into dynamic models for NTDs. Here we consider the complexities and challenges for determining the relationship between cumulative pathogen exposure and morbidity at the individual and population levels, drawing on case studies for trachoma, schistosomiasis and foodborne trematodiasis. We explore potential frameworks for explicitly incorporating long-term morbidity into NTD transmission models, and consider the insights such frameworks may bring in terms of policy-relevant projections for the elimination era. This article is part of the theme issue 'Challenges and opportunities in the fight against neglected tropical diseases: a decade from the London Declaration on NTDs'.

Tungiasis Stigma and Control Practices in a Hyperendemic Region in Northeastern Uganda

Neglected tropical diseases are known to be highly stigmatized conditions. This study investigates tungiasis-related stigma and control practices in the impoverished Napak District in rural northeastern Uganda, where tungiasis is hyperendemic and effective treatment is unavailable. We conducted a questionnaire survey with the main household caretakers (n = 1329) in 17 villages and examined them for tungiasis. The prevalence of tungiasis among our respondents was 61.0%. Questionnaire responses showed that tungiasis was perceived as a potentially serious and debilitating condition and that tungiasis-related stigma and embarrassment were common. Among the respondents, 42.0% expressed judging attitudes, associating tungiasis with laziness, carelessness, and dirtiness, and 36.3% showed compassionate attitudes towards people with tungiasis. Questionnaire responses further indicated that people made an effort to keep their feet and house floors clean (important tungiasis prevention measures), but lack of water was a common problem in the area. The most frequent local treatment practices were hazardous manual extraction of sand fleas with sharp instruments and application of various and sometimes toxic substances. Reliable access to safe and effective treatment and water are therefore key to reducing the need for dangerous treatment attempts and breaking the vicious cycle of tungiasis stigma in this setting marked by poverty.

Silver and copper-benznidazole derivatives as potential antiparasitic metallodrugs: Synthesis, characterization, and biological evaluation

Currently the only drug available to treat Chagas disease in Brazil is benznidazole (BZN). Therefore, there is an urgent need to discover and develop new anti- Trypanosoma cruzi candidates. In our continuous effort to enhance clinical antiparasitic drugs using synergistic strategy, BZN was coordinated to silver and copper ions to enhance its effectiveness to treat that illness. In this work, the syntheses of four novel metal-BZN complexes, [Ag(BZN)₂]NO₃·H₂O (1), [CuCl₂(BZN)(H₂O)]·1/2CH₃CN (2), [Ag(PPh₃)₂(BZN)₂]NO₃·H₂O (3), and [Cu(PPh₃)₂(BNZ)₂]NO₃·2H₂O (4), and their characterization using multiple analytical and spectroscopic techniques such as Infrared (FTIR), Nuclear Magnetic Resonance (¹H, ¹³C, ³¹P), UV-Visible (UV-Vis), Electron Paramagnetic Resonance (EPR), conductivity and elemental analysis are described. IC₅₀ (Half-maximal inhibitory concentration) values of Ag-BZN compounds are about five to ten times lower than benznidazole itself in both proliferation stages of the parasite (epimastigotes and amastigotes). The cytotoxicity of both compounds in human cells (fibroblasts and hepatocytes) are comparable to BZN, indicating that Ag-BZN complexes can be more selective than BZN.

Vaccines against Emerging and Neglected Infectious Diseases: An Overview

Neglected Tropical Diseases (NTDs) are a group of diseases that are highly prevalent in tropical and subtropical regions, and closely associated with poverty and marginalized populations. Infectious diseases affect over 1.6 billion people annually, and vaccines are the best prophylactic tool against them. Along with NTDs, emerging and reemerging infectious diseases also threaten global public health, as they can unpredictably result in pandemics. The recent advances in vaccinology allowed the development and licensing of new vaccine platforms that can target and prevent these diseases. In this work, we discuss the advances in vaccinology and some of the difficulties found in the vaccine development pipeline for selected NTDs and emerging and reemerging infectious diseases, including HIV, Dengue, Ebola, Chagas disease, malaria, leishmaniasis, zika, and chikungunya.

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.

Computational investigation of the alkaloids of Pilocarpus microphyllus species as phytopharmaceuticals for the inhibition of sterol 14α-demethylase protease of Trypanosoma cruzi

Trypanosoma cruzi is a protozoan transmitted by the insect Triatoma infestans, popularly known as kissing bug. This protozoan causes the Chagas disease, a Neglected Tropical Disease. This study aimed to investigate, through DFT method and B3LYP hybrid functional, the physicochemical, pharmacokinetic, and pharmacodynamic properties of the alkaloids present in the leaves of the species Pilocarpus microphyllus (jaborandi) as a potential inhibitory activity on the protease sterol 14α-demethylase of T. cruzi associated with the techniques of molecular docking, molecular dynamics, MM-PBSA and ADMET predictions. The molecules of isopilosine, epiisopiloturine, epiisopilosine, and pilosine showed up the lowest binding energies by molecular docking, good human intestinal absorption, low penetration in the blood-brain barrier, antiprotozoal and anticarcinogenic activities in ADMET studies. It has been observed a better binding affinity of the sterol 14α-demethylase protease with isopilosine in molecular dynamics and MM-PBSA studies, which indicates it as a potential drug candidate for Chagas disease.Communicated by Ramaswamy H. Sarma.

Facing Diseases Caused by Trypanosomatid Parasites: Rational Design of Pd and Pt Complexes With Bioactive Ligands

Human African Trypanosomiasis (HAT), Chagas disease or American Trypanosomiasis (CD), and leishmaniases are protozoan infections produced by trypanosomatid parasites belonging to the kinetoplastid order and they constitute an urgent global health problem. In fact, there is an urgent need of more efficient and less toxic chemotherapy for these diseases. Medicinal inorganic chemistry currently offers an attractive option for the rational design of new drugs and, in particular, antiparasitic ones. In this sense, one of the main strategies for the design of metal-based antiparasitic compounds has been the coordination of an organic ligand with known or potential biological activity, to a metal centre or an organometallic core. Classical metal coordination complexes or organometallic compounds could be designed as multifunctional agents joining, in a single molecule, different chemical species that could affect different parasitic targets. This review is focused on the rational design of palladium(II) and platinum(II) compounds with bioactive ligands as prospective drugs against trypanosomatid parasites that has been conducted by our group during the last 20 years.

Hapten Synthesis and Monoclonal Antibody Preparation for Simultaneous Detection of Albendazole and Its Metabolites in Animal-Origin Food

Albendazole (ABZ) is one of the benzimidazole anthelmintics, and the overuse of ABZ in breeding industry can lead to drug resistance and a variety of toxic effects in humans. Since the residue markers of ABZ are the sum of ABZ and three metabolites (collectively referred to as ABZs), albendazole-sulfone (ABZSO₂), albendazole-sulfoxide (ABZSO), and albendazole-2-amino-sulfone (ABZNH₂SO₂), an antibody able to simultaneously recognize ABZs with high affinity is in urgent need to develop immunoassay for screening purpose. In this work, an unreported hapten, 5-(propylthio)-1H-benzo[d]imidazol-2-amine, was designed and synthesized, which maximally exposed the characteristic sulfanyl group of ABZ to the animal immune system to induce expected antibody. One monoclonal antibody (Mab) that can simultaneously detect ABZs was obtained with IC₅₀ values of 0.20, 0.26, 0.77, and 10.5 μg/L for ABZ, ABZSO₂, ABZSO, and ABZNH₂SO₂ in ic-ELISA under optimized conditions respectively, which has been never achieved in previous reports. For insight into the recognition profiles of the Mab, we used computational chemistry method to parameterize cross-reactive molecules in aspects of conformation, electrostatic fields, and hydrophobicity, revealing that the hydrophobicity and conformation of characteristic group of molecules might be the key factors that together influence antibody recognition with analytes. Furthermore, the practicability of the developed ic-ELISA was verified by detecting ABZs in spiked milk, beef, and liver samples with recoveries of 60% to 108.8% and coefficient of variation (CV) of 1.0% to 15.9%.

Are current preventive chemotherapy strategies for controlling and eliminating neglected tropical diseases cost-effective?

Neglected tropical diseases (NTDs) remain a significant cause of morbidity and mortality in many low-income and middle-income countries. Several NTDs, namely lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminthiases (STH) and trachoma, are predominantly controlled by preventive chemotherapy (or mass drug administration), following recommendations set by the WHO. Over one billion people are now treated for NTDs with this strategy per year. However, further investment and increased domestic healthcare spending are urgently needed to continue these programmes. Consequently, it is vital that the cost-effectiveness of preventive chemotherapy is understood. We analyse the current estimates on the cost per disability-adjusted life year (DALY) of the preventive chemotherapy strategies predominantly used for these diseases and identify key evidence gaps that require further research. Overall, the reported estimates show that preventive chemotherapy is generally cost-effective, supporting WHO recommendations. More specifically, the cost per DALY averted estimates relating to community-wide preventive chemotherapy for lymphatic filariasis and onchocerciasis were particularly favourable when compared with other public health interventions. Cost per DALY averted estimates of school-based preventive chemotherapy for schistosomiasis and STH were also generally favourable but more variable. Notably, the broader socioeconomic benefits are likely not being fully captured by the DALYs averted metric. No estimates of cost per DALY averted relating to community-wide mass antibiotic treatment for trachoma were found, highlighting the need for further research. These findings are important for informing global health policy and support the need for continuing NTD control and elimination efforts.

Building supply chain capacity for neglected tropical diseases: experience from the Ascend West and Central Africa programme

The Ascend West and Central Africa programme, funded by the UK Foreign, Commonwealth and Development Office (FCDO) is supporting integrated preventative chemotherapy for up to five neglected tropical diseases (NTDs), including intestinal worms, lymphatic filariasis, river blindness, trachoma and schistosomiasis. The programme is implemented across 13 countries by a consortium of four leading international development partners: Sightsavers, Liverpool School of Tropical Medicine, Schistosomiasis Control Initiative Foundation and Mott Macdonald. This paper presents messages learnt from country assessments that took place prior to the global outbreak of coronavirus disease 2019 (COVID-19). These messages remain relevant post-COVID-19, with greater priority being given to the challenges for national NTD programmes in continuing to deliver mass drug administration (MDA) during the pandemic. Stakeholder coordination from the earliest stages of the pandemic has occurred at two levels: in the first mile with global partners of the NTD Supply Chain Forum and in the last mile with implementing partners in each country. This has been instrumental to manage delayed MDA, including the impact delays have on the shipment of NTD donated drugs and the distribution of stock held in country. The Ascend West and Central Africa programme is supporting countries with the resumption of MDA through a risk assessment and mitigation action (RAMA) process.

The Role of Nitro (NO2-), Chloro (Cl), and Fluoro (F) Substitution in the Design of Antileishmanial and Antichagasic Compounds

Neglected tropical diseases (NTDs) are responsible for over 500,000 deaths annually and are characterized by multiple disabilities. Leishmaniasis and Chagas diseases are among the most severe NTDs, and are caused by the Leishmania sp and Trypanosoma cruzi, respectively. Glucantime, pentamidine, and miltefosine are commonly used to treat leishmaniasis, whereas nifurtimox, benznidazole are current treatments for Chagas disease. However, these treatments are associated with drug resistance and severe side effects. Hence, the development of synthetic products, especially those containing N0₂, F, or Cl, are known to improve biological activity. The present work summarizes the information on the antileishmanial and antitrypanosomal activity of nitro-, chloro-, and fluorosynthetic derivatives. Scientific publications referring to halogenated derivatives in relation to antileishmanial and antitrypanosomal activities were hand-searched in databases such as SciFinder, Wiley, Science Direct, PubMed, ACS, Springer, Scielo, and so on. According to the literature information, more than 90 compounds were predicted as lead molecules with reference to their IC₅₀/EC₅₀ values in in vitro studies. It is worth mentioning that only active compounds with known cytotoxic effects against mammalian cells were considered in the present study. The observed activity was attributed to the presence of nitro-, fluoro-, and chloro-groups in the compound backbone. All in all, nitro and halogenated derivatives are active antileishmanial and antitrypanosomal compounds and can serve as the baseline for the development of new drugs against leishmaniasis and Chagas disease. However, efforts in in vitro and in vivo toxicity studies of the active synthetic compounds is still needed. Pharmacokinetic studies and the mechanism of action of the promising compounds need to be explored. The use of new catalysts and chemical transformation can afford unexplored halogenated compounds with improved antileishmanial and antitrypanosomal activity.

Achieving Elimination as a Public Health Problem for Schistosoma mansoni and S. haematobium: When Is Community-Wide Treatment Required?

The World Health Organization (WHO) has set elimination as a public health problem (EPHP) as a goal for schistosomiasis. As the WHO treatment guidelines for schistosomiasis are currently under revision, we investigate whether school-based or community-wide treatment strategies are required for achieving the EPHP goal. In low- to moderate-transmission settings with good school enrolment, we find that school-based treatment is sufficient for achieving EPHP. However, community-wide treatment is projected to be necessary in certain high-transmission settings as well as settings with low school enrolment. Hence, the optimal treatment strategy depends on setting-specific factors such as the species present, prevalence prior to treatment, and the age profile of infection.

Computational Design and Preliminary Serological Analysis of a Novel Multi-Epitope Vaccine Candidate against Onchocerciasis and Related Filarial Diseases

: Onchocerciasis is a skin and eye disease that exerts a heavy socio-economic burden, particularly in sub-Saharan Africa, a region which harbours greater than 96% of either infected or at-risk populations. The elimination plan for the disease is currently challenged by many factors including amongst others; the potential emergence of resistance to the main chemotherapeutic agent, ivermectin (IVM). Novel tools, including preventative and therapeutic vaccines, could provide additional impetus to the disease elimination tool portfolio. Several observations in both humans and animals have provided evidence for the development of both natural and artificial acquired immunity. In this study, immuno-informatics tools were applied to design a filarial-conserved multi-epitope subunit vaccine candidate, (designated Ov-DKR-2) consisting of B-and T-lymphocyte epitopes of eight immunogenic antigens previously assessed in pre-clinical studies. The high-percentage conservation of the selected proteins and epitopes predicted in related nematode parasitic species hints that the generated chimera may be instrumental for cross-protection. Bioinformatics analyses were employed for the prediction, refinement, and validation of the 3D structure of the Ov-DKR-2 chimera. In-silico immune simulation projected significantly high levels of IgG1, T-helper, T-cytotoxic cells, INF-γ, and IL-2 responses. Preliminary immunological analyses revealed that the multi-epitope vaccine candidate reacted with antibodies in sera from both onchocerciasis-infected individuals, endemic normals as well as loiasis-infected persons but not with the control sera from European individuals. These results support the premise for further characterisation of the engineered protein as a vaccine candidate for onchocerciasis.

Synthesis, characterization and antiparasitic activity of organometallic derivatives of the anthelmintic drug albendazole

Helminthiases, a group of neglected tropical diseases, affect more than one billion people mainly in tropical and subtropical regions. Moreover, major intestinal protozoa have a significant impact on global public health. Albendazole (ABZ) is a broad-spectrum anthelmintic recommended by the World Health Organisation (WHO). However, drug resistance is emerging due to its widespread use. In order to tackle this problem, taking into account the spectacular results obtained with ferroquine, an organometallic derivatization of the antimalarial drug chloroquine, we have prepared, in this study, a series of new ferrocenyl and ruthenocenyl derivatives of the organic drug ABZ and assessed their activity against different helminths and protozoans, namely Trichuris muris, Heligmosomoides polygygrus, Schistosoma mansoni, Giardia lamblia, Haemonchus contortus and Toxoplasma gondii. The ferrocene-containing ABZ analogue 2d exhibited over 70% activity against T. muris adults in vitro at 200 μM and no toxicity to mammalian cells (IC50 >100 μM). H. polygyrus adults were not affected by any of the derivatives tested. Against T. gondii, the ferrocene-containing ABZ analogues 1a and 2d showed better in vitro activity than ABZ and low toxicity to the host cells. The activity of the analogous ruthenocenyl compound 2b against S. mansoni and T. gondii in vitro might be attributed to its toxicity towards the host cells rather than a specific antiparasitic activity. These results demonstrate that the derivatives show a species specific in vitro activity and the choice of the organometallic moieties attached to the organic drug is playing a very important role. Two of our organometallic compounds, namely 1b and 2d, were tested in T. muris infected mice. At a 400 mg kg-1 dose, the compounds showed moderate worm burden reductions but low worm expulsion rates. Overall, this work, which is one of the first studies reporting the potential of organometallic compounds on a very broad range of parasitic helminths and protozoan, is a clear confirmation of the potential of organometallic complexes against parasites of medical and veterinary importance.

Loop-Mediated Isothermal Amplification as Point-of-Care Diagnosis for Neglected Parasitic Infections

The World Health Organisation (WHO) has placed twenty diseases into a group known as neglected tropical diseases (NTDs), twelve of them being parasitic diseases: Chagas’ disease, cysticercosis/taeniasis, echinococcosis, food-borne trematodiasis, human African trypanosomiasis (sleeping sickness), leishmaniasis, lymphatic filariasis, onchocerciasis (river blindness), schistosomiasis, soil-transmitted helminthiasis (ascariasis, hookworm, trichuriasis), guinea-worm and scabies. Such diseases affect millions of people in developing countries where one of the main problems concerning the control of these diseases is diagnosis-based due to the most affected areas usually being far from laboratories having suitable infrastructure and/or being equipped with sophisticated equipment. Advances have been made during the last two decades regarding standardising and introducing techniques enabling diagnoses to be made in remote places, i.e., the loop-mediated isothermal amplification (LAMP) technique. This technique’s advantages include being able to perform it using simple equipment, diagnosis made directly in the field, low cost of each test and the technique’s high specificity. Using this technique could thus contribute toward neglected parasite infection (NPI) control and eradication programmes. This review describes the advances made to date regarding LAMP tests, as it has been found that even though several studies have been conducted concerning most NPI, information is scarce for others.

Alkyl and Aryl Derivatives Based on p-Coumaric Acid Modification and Inhibitory Action against Leishmania braziliensis and Plasmodium falciparum

In low-income populations, neglected diseases are the principal cause of mortality. Of these, leishmaniasis and malaria, being parasitic, protozoan infections, affect millions of people worldwide and are creating a public health problem. The present work evaluates the leishmanicidal and antiplasmodial action of a series of twelve p-coumaric acid derivatives. Of the tested derivatives, eight presented antiparasitic activities 1–3, 8–12. The hexyl p-coumarate derivative (9) (4.14 ± 0.55 μg/mL; selectivity index (SI) = 2.72) showed the highest leishmanicidal potency against the Leishmania braziliensis amastigote form. The results of the molecular docking study suggest that this compound inhibits aldehyde dehydrogenase (ALDH), mitogen-activated kinase protein (MPK4), and DNA topoisomerase 2 (TOP2), all of which are key enzymes in the development of Leishmania braziliensis. The data indicate that these enzymes interact via Van der Waals bonds, hydrophobic interactions, and hydrogen bonds with phenolic and aliphatic parts of this same compound. Of the other compounds analyzed, methyl p-coumarate (64.59 ± 2.89 μg/mL; IS = 0.1) demonstrated bioactivity against Plasmodium falciparum. The study reveals that esters presenting a p-coumarate substructure are promising for use in synthesis of derivatives with good antiparasitic profiles.

Impacts of host gender on Schistosoma mansoni risk in rural Uganda-A mixed-methods approach

Background

The World Health Organization identified Uganda as one of the 10 highly endemic countries for schistosomiasis. Annual mass drug administration (MDA) with praziquantel has led to a decline in intensity of Schistosoma mansoni infections in several areas. However, as hotspots with high (re)infection rates remain, additional research on risk factors and implementing interventions to complement MDA are required to further reduce disease burden in these settings. Through a mixed-methods study we aimed to gain deeper understanding of how gender may impact risk and reinfection in order to inform disease control programmes and ascertain if gender-specific interventions may be beneficial.

Methodology/Principal findings

In Bugoto, Mayuge District, Eastern Uganda we conducted ethnographic observations (n = 16) and examined epidemiology (n = 55) and parasite population genetics (n = 16) in school-aged children (SAC), alongside a community-wide household survey (n = 130). Water contact was frequent at home, school and in the community and was of domestic, personal care, recreational, religious or commercial nature. Qualitative analysis of type of activity, duration, frequency, level of submersion and water contact sites in children showed only few behavioural differences in water contact between genders. However, survey data revealed that adult women carried out the vast majority of household tasks involving water contact. Reinfection rates (96% overall) and genetic diversity were high in boys (pre-He = 0.66; post-He = 0.67) and girls (pre-He = 0.65; post-He = 0.67), but no differences in reinfection rates (p = 0.62) or genetic diversity by gender before (p = 0.54) or after (p = 0.97) treatment were found.

Conclusions/Significance

This mixed methods approach showed complementary findings. Frequent water exposure with few differences between boys and girls was mirrored by high reinfection rates and genetic diversity in both genders. Disease control programmes should consider the high reinfection rates among SAC in remaining hotspots of schistosomiasis and the various purposes and settings in which children and adults are exposed to water.

Globally, over 230 million people are infected with schistosomiasis, an infectious disease caused by parasitic helminths. Humans can get infected when they contact water which contains Schistosoma parasites. Although the disease can be treated with a drug, people get rapidly reinfected in certain high-transmission settings. Drug treatment alone may not be sufficient to eliminate this disease and additional interventions such as health promotion or improvements in water and sanitation need to be scaled up. To provide recommendations to these control programmes we carried out interdisciplinary research in Eastern Uganda to understand the influence of gender on schistosomiasis risk. We found that the water contact behaviour of boys and girls is quite similar, and we did not see differences in reinfection or genetic diversity of the parasite between boys and girls. Differences in water contact between genders is greater in adults, and further research is required for these individuals. In this setting, infection rates are high in school-aged children and there are no differences between genders. These results emphasise improved control efforts for all school-aged children in communities like these. Our interdisciplinary approach provided complementary findings. Such an integrated approach can therefore have more power to meaningfully inform policy on schistosomiasis control.

Programmatic implications of the TUMIKIA trial on community-wide treatment for soil-transmitted helminths: further health economic analyses needed before a change in policy

School-based deworming programmes are currently the main approach used to control the soil-transmitted helminths (STHs). A key unanswered policy question is whether mass drug administration (MDA) should be targeted to the whole community instead, and several trials in this area have been conducted or are currently on-going. A recent well-conducted trial demonstrated that successful community-wide treatment is a feasible strategy for STH control and can be more effective than school-based treatment in reducing prevalence and intensity of hookworm infection. However, we would argue that it is vital that these findings are not taken out of context or over generalised, as the additional health benefits gained from switching to community-wide treatment will vary depending on the STH species and baseline endemicity. Moreover, community-wide treatment will typically be more expensive than school-based treatment. The epidemiological evidence for an additional benefit from a switch to community-wide treatment has yet to be proven to represent “good value for money” across different settings. Further work is needed before changes in policy are made regarding the use of community-wide treatment for STH control, including comprehensive assessments of its additional public health benefits and costs across a range of scenarios, accounting for the presence of alternative treatment delivery platforms.

The division of labour between community medicine distributors influences the reach of mass drug administration: A cross-sectional study in rural Uganda

Background

Despite decades of community-based mass drug administration (MDA) for neglected tropical diseases, it remains an open question as to what constitutes the best combination of community medicine distributors (CMDs) for achieving high (>65%/75%) treatment rates within a village.

Methods

Routine community-based MDA was evaluated in Mayuge District, Uganda. For one month, we tracked 6,148 individuals aged 1+ years in 1,118 households from 28 villages. Praziquantel, albendazole, and ivermectin were distributed to treat Schistosoma mansoni, lymphatic filariasis, and soil-transmitted helminths. The similarity/diversity between CMDs was observed and used to predict the division of labour and overall village treatment rates. The division of labour was calculated by dividing the lowest treatment rate by the highest treatment rate achieved by two CMDs within a village. CMD similarity was measured for 16 characteristics including friendship network overlap, demographic and socioeconomic factors, methods of CMD selection, and years as CMD. Relevant variables for MDA outcomes were selected through least absolute shrinkage and selection operators with leave-one-out cross validation. Final models were run with ordinary least squares regression and robust standard errors.

Results

The percentage of individuals treated with at least one drug varied across villages from 2.79–89.74%. The only significant predictor (p-value<0.05) of village treatment rates was the division of labour. The estimated difference between a perfectly equal (a 50–50 split of individuals treated) and unequal (one CMD treating no one) division of labour was 39.69%. A direct tie (close friendship) between CMDs was associated with a nearly twofold more equitable distribution of labour when compared to CMDs without a direct tie.

Conclusions

An equitable distribution of labour between CMDs may be essential for achieving treatment targets of 65%/75% within community-based MDA. To improve the effectiveness of CMDs, national programmes should explore interventions that seek to facilitate communication, friendship, and equal partnership between CMDs.

Community-based mass drug administration (MDA) uses volunteers within at-risk communities to distribute preventive chemotherapies en masse for neglected tropical diseases. Treatment rates achieved by community medicine distributors (CMDs) vary widely and can undermine morbidity control. We studied routine community-based MDA in 28 villages near Lake Victoria in Uganda. There were two CMDs per village who were tasked with moving from home-to-home to administer praziquantel, albendazole, and ivermectin for schistosomiasis, lymphatic filariasis, and soil-transmitted helminths. We observed treatment outcomes for 6,148 eligible individuals aged 1+ years. Here we identified the best combination of CMD characteristics for achieving high village-level treatment rates. We found that a more equal division of labour (e.g. 50–50 split between how many people each CMD treated) was associated with higher treatment rates when compared to CMDs with an unequal division of labour (e.g. one CMD treating no one). CMDs who were friends were more likely to have a division of labour that was nearly twofold more equal than CMDs who were not friends. The similarity of CMDs with respect to network, demographic, or socioeconomic characteristics did not influence village treatment rates. National programmes should explore interventions that seek to facilitate communication, friendship, and equal partnership between CMDs.