Incorporating a rapid-impact package for neglected tropical diseases with programs for HIV/AIDS, tuberculosis, and malaria

Genetic diversity in Leishmania infantum and Leishmania tropica isolates from human and canine hosts in northern Morocco

This study investigated nine provinces in northern Morocco and collected 275 skin scraping, 22 bone marrow aspirates, and 89 fine needle aspirations from suspected cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL) patients and potentially infected dogs. Molecular analysis using ITS1 RFLP PCR and RT-PCR revealed a higher prevalence of L. infantum (66.18 %; χ2 = 28.804; df = 1; P-value = 8.01e-08) than L. tropica in skin scraping, with L. infantum being the sole causative agent for both VL and canine leishmaniasis. L. infantum was predominantly found in most provinces, while L. tropica was relatively more dominant in Taza Province. Discriminant Analysis of Principal Components (DAPC) revealed distinct clustering between L. tropica and the other three species. However, no small subset of SNPs could clearly differentiate between Infantum_CL, Infantum_VL, and CanL, as they likely share a significant genetic background. The high rate of L. infantum could be attributed to the abundance of sand fly species transmitting VL. In Taza Province, Phlebotomus sergenti, responsible for anthroponotic CL, is the most abundant species. DNA sequencing demonstrated sequence heterogeneity in L. infantum (variants 1-9) and L. tropica (variants 1-7). Phylogenetic analysis showed a distinct separation between L. tropica and L. infantum strains, with an overlap among L. infantum strains isolated from cutaneous, visceral, and canine cases, and dogs serving as the central population for L. infantum.

Geospatial analysis and prevalence of Schistosoma mansoni and soil-transmitted helminth infections in an endemic area in Eastern Brazilian Amazon

OBJECTIVES

This study evaluated the occurrence of Schistosoma mansoni and soil-transmitted helminths in an endemic area in the Eastern Brazilian Amazon, analysing prevalence and spatial distribution.

METHODS

The study was conducted in four localities of Primavera Municipality, in Pará state. Data was obtained from the Decit 40/2012 project and the participants were divided into five age range categories for evaluation: children, adolescents, young adults, adults and elderly individuals. For the diagnostic tests, Kato-Katz slides were prepared to detect S. mansoni and soil-transmitted helminths eggs. The spatial distribution map and the Kernel Density Estimation were performed to assess the presence and location of infections.

RESULTS

Stool samples revealed the presence of hookworms, S. mansoni, Ascaris lumbricoides and Trichuris trichiura eggs. Mono-, bi- and poly-parasitic infections were observed, with a significant prevalence of hookworm monoparasitism.

CONCLUSIONS

The high frequency of children infected with soil-transmitted helminths confirms their significance as an ongoing public health problem in the poorest municipalities of Brazil. The Geographic Information System plays a crucial role in environmental surveillance and in the control of epidemics and endemic diseases, enabling accurate assessment and informed decision-making for their control.

Understanding how neglected tropical diseases programs in five Asia-Pacific countries adjusted to the COVID-19 pandemic: A qualitative study

BACKGROUND

Following the COVID-19 pandemic declaration, the World Health Organization recommended suspending neglected tropical diseases (NTD) control activities as part of sweeping strategies to minimise COVID-19 transmission. Understanding how NTD programs were impacted and resumed operations will inform contingency planning for future emergencies. This is the first study that documents how South-East Asian and Pacific NTD programs addressed challenges experienced during the COVID-19 pandemic.

METHODOLOGY/PRINCIPAL FINDINGS

Data was collected through semi-structured interviews with 11 NTD Program Coordinators and related personnel from Fiji, Papua New Guinea, The Philippines, Timor-Leste, and Vanuatu. Constructivist grounded theory methods were drawn on to generate an explanation of factors that enabled or hindered NTD program operations during the COVID-19 pandemic. The COVID-19 pandemic disrupted NTD programs in all countries. Some programs implemented novel strategies by partnering with services deemed essential or used new communications technology to continue (albeit scaled-back) NTD activities. Strong relationships to initiate cross-program integration, sufficient resources to implement adapted activities, and dedicated administrative systems were key enabling factors for recommencement. As the COVID-19 pandemic continued, exacerbating health resources scarcity, programs faced funding shortages and participants needed to find efficiencies through greater integration and activity prioritisation within their NTD units. Emphasising community-led approaches to restore trust and engagement was critical after widespread social anxiety and disconnection.

CONCLUSIONS/SIGNIFICANCE

Sustaining effective NTD programs during a global emergency goes beyond managing immediate activity disruptions and requires attention to how NTD programs can be better ensconced within wider health programs, administrative, and social systems. This study underscores the importance of pre-emergency planning that reinforces NTD control programs as a critical service at all health systems levels, accompanied by governance arrangements that increase NTD staff control over their operations and strategies to maintain strong community relationships. Ensuring NTD units are supported via appropriate funding, personnel, and bureaucratic resources is also required.

A Journey in Science: Molecular vaccines for global child health in troubled times of anti-science

My scientific life in translational medicine runs in two parallel, yet often converging paths. The first, is four-decade-long commitment to develop new vaccines for parasitic and neglected tropical diseases, as well as pandemic threats. This includes a vaccine for human hookworm infection that I began as an MD-PhD student in New York City in the 1980s, and a new low-cost COVID vaccine that reached almost 100 million people in low- and middle-income countries. Alongside this life in scientific research, is one in public engagement for vaccine and neglected disease diplomacy to ensure that people who live in extreme poverty can benefit from access to biomedical innovations. A troubling element has been the daunting task of countering rising antivaccine activism, which threatens to undermine our global vaccine ecosystem. Yet, this activity may turn out to become just as important for saving lives as developing new vaccines.

Subcellular particles for characterization of host-parasite interactions

Parasitic diseases remain a major global health problem for humans. Parasites employ a variety of strategies to invade and survive within their hosts and to manipulate host defense mechanisms, always in the pathogen's favor. Extracellular vesicles (EVs), membrane-bound nanospheres carrying a variety of bioactive compounds, were shown to be released by the parasites during all stages of the infection, enabling growth and expansion within the host and adaptation to frequently changing environmental stressors. In this review, we discuss how the use of existing nanotechnologies and high-resolution imaging tools assisted in revealing the role of EVs during parasitic infections, enabling the quantitation, visualization, and detailed characterization of EVs. We discuss here the cases of malaria, Chagas disease and leishmaniasis as examples of parasitic neglected tropical diseases (NTDs). Unraveling the EVs' role in the NTD pathogenesis may enormously contribute to their early and reliable diagnostic, effective treatment, and prevention.

Have there been efforts to integrate malaria and schistosomiasis prevention and control programs? A scoping review of the literature

Malaria and schistosomiasis are two important parasitic diseases that are a particular threat to young children and pregnant women in sub-Saharan Africa. Malaria and schistosomiasis prevention and control strategies primarily focus on the distribution of long-lasting insecticidal nets and the delivery of praziquantel tablets to at-risk populations in high burden settings through mass drug administration, respectively. The objective of this scoping review was to identify previous efforts to integrate malaria and schistosomiasis prevention and control programs in the literature and to summarize the strategies and approaches used in these programs following the PRISMA-ScR guidelines. We reviewed published and grey literature using a combination of keywords and search terms following themes surrounding "malaria", "Plasmodium falciparum", "Anopheles", "schistosomiasis", "Schistosoma haematobium", "Schistosoma mansoni", and "snails". Neither a date limit nor relevant terms for prevention and control were used. Out of 6374, eight articles were included in the scoping review-three articles investigated the integration of mass drug administration for schistosomiasis with the administration of antimalarials, four articles investigated the effect of administering antimalarials on malaria, schistosomiasis, and their co-infection, and one article assessed the impact of an educational intervention on malaria and schistosomiasis knowledge and preventative behaviors. Our findings suggest that there is an opportunity to link disease control programs to increase access and coverage of interventions to improve outcomes for malaria, schistosomiasis, and their co-infection. Further research is needed on the potential benefits, feasibility, and cost-effectiveness of integrating malaria and schistosomiasis prevention and control programs.

Cutaneous Leishmaniasis Prevalence and Clinical Overview: A Single Center Study from Saudi Arabia, Eastern Region, Al-Ahsa

Cutaneous leishmaniasis (CL) is a vector-borne parasitic disease that is transmitted via the bites of infected female sandflies. CL has been endemic in several countries worldwide for many decades, and numerous cases have been reported in Saudi Arabia, particularly across six regions; one of which is AL-Ahsa. Our research aimed to evaluate the epidemiological situation of CL among the patients in Al-Ahsa, Eastern region, Kingdom of Saudi Arabia, during the period from 2017 to 2023. The data were collected from the patients' registries and included 245 patients who were diagnosed with CL in Al-Ahsa, Saudi Arabia. Fewer than half of the cases (47.8%) were Saudi patients, with a significant number of them being males (84.5%). Over half of the cases (52.7%) were aged between 21 and 40 years, and about three-quarters (74.7%) of the cases resided in rural areas. Regarding the nature of the lesions, 38.4% of the cases had one lesion, which was mainly distributed on a lower extremity (62.0%) or an upper extremity (52.2%). A high percentage of the lesions (75.2%) were wet lesions and caused by L. major. Concerning risk factors, a greater number of patients (71.4%) had been in rural areas within the last three months. Additionally, more than half of the cases (54.3%) had close contact with rodents, followed by birds (28.2%), sheep (22.0%), dogs (16.3%), and other animals (1.2%). The results showed a low number of reported CL cases in 2020 and 2021, followed by a surge in 2022 and 2023. The study shows that cutaneous leishmaniasis is still a public health problem in Al-Ahsa and is primarily associated with rural areas.

Unfolded protein response pathway in leishmaniasis: A review

Alteration in the physiological state of the endoplasmic reticulum (ER) leads to the specific response known as unfolded protein response (UPR) or ER stress response. The UPR is driven by three sensor proteins, namely: Inositol-Requiring Enzyme 1, Protein Kinase RNA-like ER kinase and Activating Transcription Factor 6 to restore ER homeostasis. Pathogenic infection can initiate UPR activation; some pathogens can subvert the UPR to promote their survival and replication. Many intracellular pathogens, including Leishmania, can interact and hijack ER for their survival and replication, triggering ER stress and subsequently ER stress response. This review aims to provide a comprehensive overview of the ER stress response in infections with the Leishmania species.

Provider and User Acceptability of Integrated Treatment for the Control of Malaria and Helminths in Saraya, South-Eastern Senegal

Integration of vertical programs for the control of malaria, schistosomiasis, and soil-transmitted helminthiasis has been recommended to achieve elimination of malaria and neglected tropical diseases (NTD) by 2030. This qualitative study was conducted within the context of a randomized controlled trial to explore the perceptions and views of parents/caregivers of at-risk children and healthcare providers to determine their acceptability of the integrated malaria-helminth treatment approach. Randomly selected parents/caregivers of children enrolled in the trial, healthcare providers, trial staff, malaria, and NTD program managers were interviewed using purpose-designed topic guides. Transcripts obtained from the interviews were coded and common themes identified using content analysis were triangulated. Fifty-seven study participants comprising 26 parents/caregivers, 10 study children aged ≥ 10 years, 15 trial staff, four healthcare providers, and two managers from the Senegal Ministry of Health were interviewed. Thirty-eight of the participants (66.7%) were males, and their ages ranged from 10 to 65 years. Overall, the integrated malaria-helminth treatment approach was considered acceptable, but the study participants expressed concerns about the taste, smell, and side effects associated with amodiaquine and praziquantel in the combination package. Reluctance to accept the medications was also observed among children aged 10 to 14 years due to peer influence and gender-sensitive cultural beliefs. Addressing concerns about the taste and smell of amodiaquine and praziquantel is needed to optimize the uptake of the integrated treatment program. Also, culturally appropriate strategies need to be put in place to cater for the inclusion of children aged 10 to 14 years in this approach.

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'.

Intestinal parasitic infections and their potential risk factors among prison inmates in Valencia, Spain

BACKGROUND

Despite the fact that prison inmates are a population at higher risk than other groups of suffering from intestinal parasite infections in relation to their living conditions, information about these diseases in prison environments is still scarce. Herein, we analyze the status of intestinal parasite infections in a Spanish prison.

METHODS

A cross-sectional study involving 528 inmates was conducted from April to June 2022 among inmates at Centro Penitenciario Picassent (Valencia, Spain). Stool specimens were examined using the direct wet mount technique, the formol-ether concentration technique, and the Ziehl-Neelsen staining method. We used STATA 16.1 for data analysis. We consider a p-value less than 0.05 significant at a 95% confidence level.

RESULTS

Of the 528 inmates (471 men and 57 women; a mean age of 41.94 years) enrolled in the study, 83 (15.7%) were infected. Only six species of protozoa were detected. The gut potential microeukaryotic pathobiont Blastocystis sp. was the predominant parasite, accounting for 37 (44.6%) of the infections. Gut parasite amebas (6.6%) and pathobionts (5.3%) were more prevalent than flagellates (2.3%). The prevalence of infection with pathogenic species (8.9%) was similar to that of non-pathogenic species (8.7%). Infection among men (15.2%) was higher than in women (0.6%) (p < 0.0001). In multivariate analysis, the country of birth (AOR = 0.31, 95% CI = 0.18-0.52) and the time spent in prison (AOR = 1.83, 95% CI = 1.06-3.14) were statistically significant associated to intestinal parasite infections (p < 0.0001 and p = 0.028, respectively).

CONCLUSION

This study found low levels of intestinal parasite infections in the CPP which could be indicative of the implementation of sanitary measures in prison environments in Spain. The less time spent in prison favor the risk of having infection while the Spanish nationality of inmates could reduce the risk of infection. The main recommendation would be to introduce routine parasitological tests upon foreigners entering prison.

Exploring the anthelmintic activity of Olea europaea L (Olive) leaves extract and oleuropein in mice naturally infected with Aspiculuris tetraptera

Oxyuriasis, caused by the nematode Enterobius vermicularis, is one of the cosmopolitan intestinal infections of humans. Aspiculuris tetraptera commonly infects mice and it is morphologically similar to E. vermicularis. Parasitic resistance reduces the efficiency of synthetic drugs and poses economic impacts on the dairy sector, thus necessitating novel anthelmintic agents. Olea europaea L. (Olive) is a bioactive plant with potent pharmacological activities. However, its effects on oxyurids are poorly known, and no studies are currently exploring olives' anthelmintic potential. In this study, we investigated the pharmacokinetic behaviors of O. europaea leaves extract (OLE) and its phenolic compound oleuropein in mice infected with A. tetraptera, in comparison with Albendazole (ABZ), a standard drug used to treat parasitic worms. Fecal flotation method was used to identify the infestation with A. tetraptera eggs by examining the stool samples from mice. Infected animals were divided into 7 groups. 250 mg/kg, 500 mg/kg, and 1000 mg/kg doses of OLE, 5 mg/kg and 20 mg/kg doses of oleuropein, 10 mg/kg of ABZ and tap water were orally administered by gavage for 7 days during treatments. Drug efficacies and statistical differences between the treatments and controls were evaluated. Our results revealed 92.43 % efficacy of ABZ, similar to 92.19 % efficacy of 1000 mg/kg of OLE. At the same time, 250 mg/kg and 500 mg/kg concentrations of OLE remained 70.03 % and 63.18 % effective in reducing worm counts. Efficacy percentages of 5 mg/kg and 20 mg/kg of oleuropein were 9.27 % and 70.56 %, respectively. Statistical analysis of ABZ was significant compared to 1000 mg/kg of OLE, which was almost equal but insignificant. In general, our results confirm the anthelmintic potential of OLE and oleuropein against mice pinworms and open the way for targeted extraction of bioactive compounds from plants to optimize its use in human and veterinary medicine.

Cytokine Gene Expression Profiles during HIV and Helminth Coinfection in Underprivileged Peri-Urban South African Adults

BACKGROUND

Intestinal helminth parasites are potent stimulators of T helper type 2 (Th2) and regulatory Th3 anti-inflammatory immune responses, while human immunodeficiency virus (HIV) infections are activators of predominantly T helper type 1(Th1) pro-inflammatory responses. Studies investigating the immune profiles of individuals coinfected with helminths and HIV are scarce. Although it is well known that helminths cause a type 2 immune response during the chronic stage of infection that is characterised by Th2 cell differentiation, eosinophil recruitment, and alternative macrophage activation, the immune mechanisms that regulate tissue damage at the time of parasite invasion are poorly understood.

AIM

The aim of the study was to determine the cytokine gene expression profiles during HIV and helminth coinfection in underprivileged South African adults living in a peri-urban area with poor sanitary conditions and a lack of clean water supply.

METHOD

Study participants (n = 164) were subdivided into uninfected controls, HIV-infected, helminth-infected, and HIV and helminth-coinfected groups. The Kato-Katz and Mini Parasep techniques and Ascaris lumbricoides-specific Immunoglobulin E (IgE) and Immunoglobulin G4 (IgG4) levels were used to detect helminth infections. Participants' HIV status was determined using two HIV1/2 antibody test kits. RNA was isolated from white blood cells for cytokine (Th1-, Th2-, and Th17-related) and transcription factor gene expression profiling using real-time PCR.

RESULTS

Multivariate regression data were adjusted for age, gender, BMI, antiretroviral treatment (ART), and nutritional supplement intake. The HIV and helminth-coinfected group had significantly higher tumour necrosis factor alpha (TNF-α) (adjusted β = 0.53, p = 0.036), interleukin 2 (IL-2) (adjusted β = 6.48, p = 0.008), and interleukin 17 (IL-17) (adjusted β = 1.16, p = 0.001) levels and lower GATA binding protein 3 (GATA3) levels (adjusted β = -0.77, p = 0.018) compared to the uninfected controls. No statistical significance was noted for Th2-related cytokines.

CONCLUSION

The coinfected group had higher proinflammatory Th1- and Th17-related cytokine gene expression profiles compared to the uninfected controls. The findings suggest that pro-inflammatory responses are elevated during coinfection, which supports the hypothesis that helminths have a deleterious effect on HIV immune responses.

Intestinal parasitic infections in a community from Pampa del Indio, Chaco (Argentina) and their association with socioeconomic and environmental factors

Neglected tropical diseases are a group of 20 disabling diseases, which, in particular, are the most common chronic infections in the most vulnerable people. This study aimed to characterize the infection by intestinal parasites (IPs) in dwellings from a peri-urban neighborhood in Pampa del Indio, Chaco (Argentina), and its association with socioeconomic and environmental variables. Single stool samples were collected from all individuals older than 1 year through household visits and processed using coprological sedimentation and flotation techniques. Standardized questionnaires were used at the household level to collect socio-economic information. Environmental variables were obtained from the Planetscope image, Landsat 8 images and remote sensors, while land-use layers were obtained through the use of a maximum likelihood algorithm. Stool samples were provided by 314 individuals. The prevalence of IPs found was 30.6% (n = 96), with a predominance of Giardia lamblia (12.7%, n = 40) and Hymenolepis nana (7.6%, n = 24). The only soil-transmitted helminth found was Strongyloides stercoralis with a 2.5% prevalence (n = 8). Individuals of adult age (> 18 years) were 0.65 times less likely to present parasitic infections with respect to children and adolescents. The only environmental variable that was closely associated with the presence of IPs, was the Normalized Difference Water Index (NDWI), a measure of humidity; being higher around houses with positive individuals. Most of the IPs found in this study were of water-borne transmission and those transmitted directly from person-to-person, therefore fecal contamination is present. We believe that the low prevalence of STH in this area, which requires a passage through the soil, is related to the environmental characteristics, which are unsuitable for the development/permanence of the infective stages of these parasites. The geospatial data and tools used herein proved to be useful for the study of the relationship between the different factors that influence the presence of IPs in a community, from an eco-health approach.

Demographic dynamics of waterborne disease and perceived associated WASH factors in Bushenyi and Sheema districts of South-Western Uganda

Water remains a significant player in spreading pathogens, including those associated with neglected tropical diseases. The implications of socio-demographic delineations of water quality, sanitation, and hygiene ("WASH") interventions are on the downswing. This study assessed waterborne diseases and perceived associated WASH factors in the Bushenyi and Sheema districts of South-Western Uganda. This study examines the linear relationship between WASH and identifies the association of specific demographic factors as well as their contributions/correlations to waterborne disease in the study area. A structured qualitative and quantitative data collection approach was adopted in face-to-face questionnaire-guided interviews of 200 respondents on eight surface water usage. Most participants, 65.5%, were females and had a higher score of knowledge of WASH (71%), 68% score on the improper practice of WASH, and 64% score on unsafe water quality. Low score for basic economic status was (57%), report of common diarrhoea was (47%), and a low incidence of waterborne disease outbreaks (27%). The principal component analysis (PCA) depicts the knowledge and practice of WASH to have a strong positive correlation (r = 0.84, p < 0.001; r = 0.82, p < 0.001); also economic status positively correlated with grade of water source, knowledge, and practice of WASH (correlation coefficient = 0.72; 0.99; 0.76 and p-values = 0.001; < 0.001; < 0.001 respectively). Occupation (p = 0.0001, OR = 6.798) was significantly associated with knowledge and practice of WASH, while age (r = -0.21, p < 0.001) was negatively associated with knowledge and practice of WASH. The basic economic status explains why "low economic population groups" in the remote villages may not effectively implement WASH, and diarrhoea was common among the population. Diarrhoea associated with unsafe water quality and improper practice of WASH is common among the study population, and there is a low incidence of waterborne disease outbreaks. Therefore, government, stakeholders, and non-governmental organisations should work together to promote proper practice of WASH conditions to limit the occurrence of diarrhoea and prevent potential waterborne disease outbreaks.

Stem-Loop Structures in Iron-Regulated mRNAs of Giardia duodenalis

Giardia duodenalis is a significant cause of waterborne and foodborne infections, day-care center outbreaks, and traveler's diarrhea worldwide. In protozoa such as Trichomonas vaginalis and Entamoeba histolytica, iron affects the growth, pathogenicity mechanisms, and expression of virulence genes. One of the proposed iron regulatory mechanisms is at the post-transcriptional level through an IRE/IRP-like (iron responsive element/iron regulatory protein) system. Recently, the expression of many putative giardial virulence factors in the free-iron levels has been reported in subsequent RNAseq experiments; however, the iron regulatory mechanism remains unknown. Thus, this work aimed to determine the effects of iron on the growth, gene expression, and presence of IRE-like structures in G. duodenalis. First, the parasite's growth kinetics at different iron concentrations were studied, and the cell viability was determined. It was observed that the parasite can adapt to an iron range from 7.7 to 500 µM; however, in conditions without iron, it is unable to survive in the culture medium. Additionally, the iron modulation of three genes was determined by RT-PCR assays. The results suggested that Actin, glucosamine-6-phosphate deaminase, and cytochrome b5 mRNA were down-regulated by iron. To investigate the presence of IRE-like structures, in silico analyses were performed for different mRNAs from the Giardia genome database. The Zuker mfold v2.4 web server and theoretical analysis were used to predict the secondary structures of the 91 mRNAs analyzed. Interestingly, the iron-induced downregulation of the genes analyzed corresponds to the location of the stem-loop structures found in their UTR regions. In conclusion, iron modulates the growth and expression of specific genes, likely due to the presence of IRE-like structures in G. duodenalis mRNAs.

Antihelminthic Activity of Lophira Lanceolata on Heligmosomoides polygyrus Using an Automated High-Throughput Method

Background

There are about 13 parasitic infections that are responsible for significant morbidity and mortality but have not received the attention they deserve; thus, they are now known as "neglected tropical diseases" (NTDs). This study was aimed at evaluating the antihelminthic activities of Lophira lanceolata using an automated high-throughput method.

Methods

The antihelminthic activity effect of the extracts against H. polygyrus was determined using an automated high-throughput method. For the egg-hatching test, 100 μL of embryonated egg suspension (60 eggs) was added to 100 μL of various concentrations of extracts, levamisole, and 1.5% DMSO in a 96-well round-bottom microtitre plate. After mixing, the 96-well microplate was placed in WMicroTracker and incubated for 24 h at 25°C; the movements were recorded every 30 minutes. The same procedure was used for the larval motility assays, where 100 μL of L1 or L2 larvae (50 larvae) were put in contact with 100 μL of various concentrations of extracts.

Results

The ovicidal activity (hatching) had an IC₅₀ of 1.4 mg/mL for the ethanol extract. The aqueous and ethanol extracts of L. lanceolata showed larvicidal activity on the L1 larvae with IC₅₀ of 1.85 mg/mL and 2.4 mg/mL, respectively, as well as on the L2 larvae with IC₅₀ values of 1.08 mg/mL and 1.02 mg/mL for the aqueous and ethanol extracts, respectively. These results showed that the aqueous extract exhibited a stronger inhibitory power on the hatching rate of parasites than ethanol extracts, while the contrary effect was observed for the larval motility assays.

Conclusion

This study provides scientific data on the use of L. lanceolata by the local population for the treatment of helminthiases. However, in vivo and toxicity tests are necessary to assess its activity and safety.

Small molecules containing chalcogen elements (S, Se, Te) as new warhead to fight neglected tropical diseases

Neglected tropical diseases (NTDs) encompass a group of infectious diseases with a protozoan etiology, high incidence, and prevalence in developing countries. As a result, economic factors constitute one of the main obstacles to their management. Endemic countries have high levels of poverty, deprivation and marginalization which affect patients and limit their access to proper medical care. As a matter of fact, statistics remain uncollected in some affected areas due to non-reporting cases. World Health Organization and other organizations proposed a plan for the eradication and control of the vector, although many of these plans were halted by the COVID-19 pandemic. Despite of the available drugs to treat these pathologies, it exists a lack of effectiveness against several parasite strains. Treatment protocols for diseases such as American trypanosomiasis (Chagas disease), leishmaniasis, and human African trypanosomiasis (HAT) have not achieved the desired results. Unfortunately, these drugs present limitations such as side effects, toxicity, teratogenicity, renal, and hepatic impairment, as well as high costs that have hindered the control and eradication of these diseases. This review focuses on the analysis of a collection of scientific shreds of evidence with the aim of identifying novel chalcogen-derived molecules with biological activity against Chagas disease, leishmaniasis and HAT. Compounds illustrated in each figure share the distinction of containing at least one chalcogen element. Sulfur (S), selenium (Se), and tellurium (Te) have been grouped and analyzed in accordance with their design strategy, chemical synthesis process and biological activity. After an exhaustive revision of the related literature on S, Se, and Te compounds, 183 compounds presenting excellent biological performance were gathered against the different causative agents of CD, leishmaniasis and HAT.

Laboratory diagnostics for human Leishmania infections: a polymerase chain reaction-focussed review of detection and identification methods

Leishmania infections span a range of clinical syndromes and impact humans from many geographic foci, but primarily the world's poorest regions. Transmitted by the bite of a female sand fly, Leishmania infections are increasing with human movement (due to international travel and war) as well as with shifts in vector habitat (due to climate change). Accurate diagnosis of the 20 or so species of Leishmania that infect humans can lead to the successful treatment of infections and, importantly, their prevention through modelling and intervention programs. A multitude of laboratory techniques for the detection of Leishmania have been developed over the past few decades, and although many have drawbacks, several of them show promise, particularly molecular methods like polymerase chain reaction. This review provides an overview of the methods available to diagnostic laboratories, from traditional techniques to the now-preferred molecular techniques, with an emphasis on polymerase chain reaction-based detection and typing methods.

Immunological Interactions between Intestinal Helminth Infections and Tuberculosis

Helminth infections are among the neglected tropical diseases affecting billions of people globally, predominantly in developing countries. Helminths’ effects are augmented by coincident tuberculosis disease, which infects a third of the world’s population. The role of helminth infections on the pathogenesis and pathology of active tuberculosis (T.B.) remains controversial. Parasite-induced suppression of the efficacy of Bacille Calmette-Guerin (BCG) has been widely reported in helminth-endemic areas worldwide. T.B. immune response is predominantly proinflammatory T-helper type 1 (Th1)-dependent. On the other hand, helminth infections induce an opposing anti-inflammatory Th2 and Th3 immune-regulatory response. This review summarizes the literature focusing on host immune response profiles during single-helminth, T.B. and dual infections. It also aims to necessitate investigations into the complexity of immunity in helminth/T.B. coinfected patients since the research data are limited and contradictory. Helminths overlap geographically with T.B., particularly in Sub-Saharan Africa. Each disease elicits a response which may skew the immune responses. However, these effects are helminth species-dependent, where some parasites have no impact on the immune responses to concurrent T.B. The implications for the complex immunological interactions that occur during coinfection are highlighted to inform government treatment policies and encourage the development of high-efficacy T.B. vaccines in areas where helminths are prevalent.

A call for loiasis to be added to the WHO list of neglected tropical diseases

Loiasis, also called African eye worm, is not currently on WHO's list of priority neglected tropical diseases, even though the risk that individuals with high Loa loa microfilarial densities will develop potentially fatal encephalopathy when they take ivermectin has complicated efforts to use mass drug administration for onchocerciasis (river blindness) and lymphatic filariasis control in co-endemic areas. At least 10 million residents of central and west Africa are thought to have loiasis, which causes painful and itchy subcutaneous oedema, arthralgia, and discomfort when adult helminths that are 3-7 cm in length are present under the conjunctiva of the eye. High levels of microfilaraemia are associated with renal, cardiac, neurological, and other sequelae, and an increased risk of death. The public health burden of loiasis could be greatly reduced with expanded use of diagnostic tests, anthelmintic treatment, and control of the Chrysops spp (tabanid flies) vectors that transmit the parasite. Loiasis should be added to the next revision of the WHO neglected tropical disease priority list, not merely because its inclusion will support the elimination of other skin and subcutaneous neglected tropical diseases, but also because of the complications caused by loiasis itself.

Recognising the potential of neglected tropical disease programmes as a platform for pandemic preparedness: the Ascend experience

Living in an increasingly interconnected world, epidemics and pandemics are increasingly likely to be a vista for the future. This, coupled with the likely devastating effects of climate change, means that humanitarian crises are likely to increase. Now, more than ever before, is the time to scale up investment in prevention and preparedness strategies, and to review our current approaches to delivering health services, including those that address neglected tropical diseases. The Ascend West and Central Africa programme has illustrated the importance of innovation, multisector partnerships, resilience and the opportunity for change.

Prevalence and distribution pattern of malaria and soil-transmitted helminth co-endemicity in sub-Saharan Africa, 2000-2018: A geospatial analysis

BACKGROUND

Limited understanding exists about the interactions between malaria and soil-transmitted helminths (STH), their potential geographical overlap and the factors driving it. This study characterised the geographical and co-clustered distribution patterns of malaria and STH infections among vulnerable populations in sub-Saharan Africa (SSA).

METHODOLOGY/PRINCIPAL FINDINGS

We obtained continuous estimates of malaria prevalence from the Malaria Atlas Project (MAP) and STH prevalence surveys from the WHO-driven Expanded Special Project for the Elimination of NTDs (ESPEN) from Jan 1, 2000, to Dec 31, 2018. Although, MAP provides datasets on the estimated prevalence of Plasmodium falciparum at 5km x 5km fine-scale resolution, we calculated the population-weighted prevalence of malaria for each implementation unit to ensure that both malaria and STH datasets were on the same spatial resolution. We incorporated survey data from 5,935 implementation units for STH prevalence and conducted the prevalence point estimates before and after 2003. We used the bivariate local indicator of spatial association (LISA analysis) to explore potential co-clustering of both diseases at the implementation unit levels among children aged 2-10 years for P. falciparum and 5-14 years for STH, living in SSA. Our analysis shows that prior to 2003, a greater number of SSA countries had a high prevalence of co-endemicity with P.falciparium and any STH species than during the period from 2003-2018. Similar prevalence and distribution patterns were observed for the co-endemicity involving P.falciparum-hookworm, P.falciparum-Ascaris lumbricoides and P.falciparum-Trichuris trichiura, before and after 2003. We also observed spatial variations in the estimates of the prevalence of P. falciparum-STH co-endemicity and identified hotspots across many countries in SSA with inter-and intra-country variations. High P. falciparum and high hookworm co-endemicity was more prevalent in West and Central Africa, whereas high P. falciparum with high A. lumbricoides and high P. falciparum with high T. trichiura co-endemicity were more predominant in Central Africa, compared to other sub-regions in SSA.

CONCLUSIONS/SIGNIFICANCE

Wide spatial heterogeneity exists in the prevalence of malaria and STH co-endemicity within the regions and within countries in SSA. The geographical overlap and spatial co-existence of malaria and STH could be exploited to achieve effective control and elimination agendas through the integration of the vertical control programmes designed for malaria and STH into a more comprehensive and sustainable community-based paradigm.

Morphogenesis Dynamics in Leishmania Differentiation

Leishmania, the causative agent of leishmaniasis, is an obligatory intracellular parasite that cycles between phagolysosome of mammalian macrophages, where it resides as round intracellular amastigotes, and the midgut of female sandflies, where it resides as extracellular elongated promastigotes. This protozoan parasite cytoskeleton is composed of stable and abundant subpellicular microtubules (SPMT). This study aims to determine the kinetics of developmental morphogenesis and assess whether microtubules remodelling is involved in this process. Using image-streaming technology, we observed that rounding of promastigotes during differentiation into amastigotes was initiated promptly after exposure to the differentiation signal. Stabilizing microtubules with taxol sped rounding, but later killed differentiating parasites if taxol was not removed. Microtubule destabilizers such as vinblastine had no effect on the rate of rounding, nor on the viability of differentiating parasites. In the reverse process, elongation is initiated after a delay of 7.5 and completed 72 h after exposure to the amastigote to the promastigote differentiation signal. During the delay, parasites became highly sensitive to treatment with microtubule destabilizers. The addition of vinblastine during the first 7.5 h halted differentiation and killed parasites. Between 8 and 24 h, parasites gradually became resistant to vinblastine and, in parallel, started to elongate. In contrast, taxol had no effect on parasite elongation, nor on the viability of these cells. In a parallel study, we showed that the Leishmania-specific protein kinase A (PKA) holoenzyme containing the LdPKAR3-C3 complex is essential for promastigote elongation. Mutant promastigotes lacking either of these proteins are round, but maintain their flagella. Here, we observed that during differentiation into amastigotes, these mutants round at the same rate as the wild type, but never exceed the WT density of round amastigotes. In the reverse process, these mutants undergo the same initial delay and then elongate at the same rate as the WT. They stop elongating when they reach 20% of elongated cells in mature promastigotes. Our analysis indicates that while promastigote rounding into amastigotes did not require microtubule remodelling, morphogenesis of round amastigotes into elongated promastigotes required microtubule rearrangement before elongation was initiated. This is the first study that investigates the dynamics of microtubules during parasite development.

Safety and effectiveness of delivering mass drug administration for helminths through the seasonal malaria chemoprevention platform among Senegalese children: study protocol for a randomised controlled trial

BACKGROUND

Malaria remains a major health problem, especially in sub-Saharan Africa where more than 90% of the disease and where nearly all deaths occur in children. Adding to this high burden is the co-existence of intestinal and genito-urinary helminth infections. Existing control programmes for these helminths are operating sub-optimally. Conversely, a malaria prevention programme, called seasonal malaria chemoprevention (SMC), introduced in 2012 has achieved more than 75% treatment coverage and prevented 75-85% cases of uncomplicated and severe malaria in children. This encouraging development supports the need to explore strategies involving the integration of helminth control with successful platforms such as SMC. This would align worm and malaria control within the Sustainable Development Goals of ending the diseases of poverty and promoting health and well-being for those at risk.

METHODS

This study will have quantitative and qualitative components. The quantitative component will be a three-arm, observer-blind, placebo-controlled, interventional study of co-administration of SMC and anthelminthic drugs to pre-school and school-age children in Saraya district, southeast Senegal. Six hundred children aged 1-14 years will be randomly assigned to receive either SMC drugs only, SMC drugs and praziquantel or SMC drugs and albendazole and praziquantel at a ratio of 1:1:1. The primary outcome will be solicited and unsolicited adverse reactions to the study medications. The secondary outcomes will be the prevalence and intensity of Plasmodium-helminth co-infection and the prevalence of anaemia and mean haemoglobin concentration. The qualitative component of the study will include the conduct of structured interviews to assess the acceptability, feasibility, enablers and barriers to the combined use of anthelminthic and SMC drugs among randomly selected parents/caregivers of children enrolled in the study and health care workers responsible for the delivery of the combined services.

DISCUSSION

This study will provide evidence to boost the public health recommendations for combined malaria and helminth control. If successful, this project will reinforce the evidence that health care systems in developing countries can be comprehensive health management rather than focussed on vertical management of a single disease.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05354258. Registered on 28 April 2022. PACTR202204794105273. Registered on 25 April 2022.

Genome-wide analysis of Schistosoma mansoni reveals limited population structure and possible praziquantel drug selection pressure within Ugandan hot-spot communities

Populations within schistosomiasis control areas, especially those in Africa, are recommended to receive regular mass drug administration (MDA) with praziquantel (PZQ) as the main strategy for controlling the disease. The impact of PZQ treatment on schistosome genetics remains poorly understood, and is limited by a lack of high-resolution genetic data on the population structure of parasites within these control areas. We generated whole-genome sequence data from 174 individual miracidia collected from both children and adults from fishing communities on islands in Lake Victoria in Uganda that had received either annual or quarterly MDA with PZQ over four years, including samples collected immediately before and four weeks after treatment. Genome variation within and between samples was characterised and we investigated genomic signatures of natural selection acting on these populations that could be due to PZQ treatment. The parasite population on these islands was more diverse than found in nearby villages on the lake shore. We saw little or no genetic differentiation between villages, or between the groups of villages with different treatment intensity, but slightly higher genetic diversity within the pre-treatment compared to post-treatment parasite populations. We identified classes of genes significantly enriched within regions of the genome with evidence of recent positive selection among post-treatment and intensively treated parasite populations. The differential selection observed in post-treatment and pre-treatment parasite populations could be linked to any reduced susceptibility of parasites to praziquantel treatment.

Antitrypanosomal and Anthelminthic Properties of Ethanol Extracts of Carica papaya Linn. and Ceiba pentandra (L) Gaertn

The most common diseases that affect low-income countries are helminthosis and trypanosomosis. In Ghana, and in many other African countries, herbal treatment of various diseases is still common. In the present study, we sought to determine the antitrypanosomal and anthelminthic activities of Carica papaya and Ceiba pentandra. The ethanol extracts of Carica papaya stem bark (PPSe) and leaves (PPLe) and ethanol extracts of Ceiba pentandra stem bark (CPSe) and leaves (CPLe) were screened against Trypanosoma brucei brucei and Pheretima posthuma worms in vitro. CPSe exhibited strong antitrypanosomal activity, while the other extracts exhibited moderate activity against T. b. brucei. All the extracts showed weak selective indices (SI) when tested on Jurkat cell lines, which is indicative of a potential toxic effect. When the extracts were screened against P. posthuma worms, only PPSe and CPSe were able to kill the worms after the exposure time at concentrations of 2.5, 5, and 10 mg/mL. PPSe was again the only extract that potentiated the anthelminthic activity of albendazole against P. posthuma worms. Preliminary phytochemical screening and GC-MS analysis revealed the presence of compounds with antitrypanosomal and anthelminthic properties. The results confirmed the potential of C. papaya and C. pentandra as remedies for trypanosomosis and helminthosis and also gives credence to their folkloric use.

Dandelion (Taraxacum officinale) Improves the Therapeutic Efficiency of Praziquantel in Experimental Schistosomiasis

PURPOSE

Although praziquantel (PZQ) has a wide use as an anti-schistosome agent, many of its imperfections and side effects have been reported in many studies. The current study aims to evaluate the curative effect of a natural dandelion extract (Taraxacum officinale) on schistosomiasis either alone or in combination with PZQ based on parasitological, immunological, histopathological and molecular investigations.

METHODS

Mice were experimentally infected with Schistosoma mansoni cercariae and then divided into four groups, Schistosoma spp.-infected untreated group (IC group), Schistosoma spp.-infected group of mice treated with dandelion (I-Dn group), Schistosoma spp.-infected group of mice treated with PZQ (I-PZQ group), and Schistosoma spp.-infected group of mice treated with both PZQ and dandelion (I-PZQ + Dn group). Treatment started 45 days' post-infection. Besides, non-infected, non-treated mice served as the negative healthy control group (HC group).

RESULTS

The present results indicated that dandelion administration significantly reduced the worm burden, ova number, and the number and diameter of hepatic granulomas as compared to the untreated infected group. The results also showed that the levels of IL-6 and TNF-α were significantly decreased in the combined treatment group (I-PZQ + Dn) as compared to the I-PZQ group. Administration of dandelion-only remarkably reduced AST and ALT activities associated with schistosomiasis. Moreover, hepatic DNA damage assessed by comet assay was significantly inhibited in the combined treated group compared to the infected untreated and PZQ treated groups.

CONCLUSION

The results concluded that combined treatment of PZQ and dandelion extract improved immune response, decreased the number and diameter of granulomas, and inhibited DNA damage, indicating a reduction in liver fibrosis associated with schistosomiasis. The present study focused on the potential effect of dandelion as an adjunct medication for therapeutic properties of PZQ.

False-positive rapid diagnostic test for malaria in new world cutaneous leishmaniasis: a tale of two travelers

We report two immigrants from Cuba seen in a US travel clinic with a confirmed diagnosis of cutaneous leishmaniasis in whom we also suspected malaria co-infection. Both individuals likely acquired leishmaniasis in the Darien Gap region of Panama during their migratory path to the United States. As part of their clinical workup to rule out malaria, a rapid malaria antigen testing for P. falciparum was obtained and reported positive in both patients, However, both a qualitative reverse transcription-polymerase chain reaction (RT-PCR) for Plasmodium falciparum in blood and repeated thick-and-thin smear direct microscopy were negative in both, deeming the rapid malaria test as a false-positive. Thus, confirmation of malaria in travelers requires thick-and-thin film microscopy. Clinicians should be aware of the growing recognition of the possibility of false-positive malaria rapid diagnostic tests in those with some forms of leishmaniasis

The effect of conditional cash transfers on the control of neglected tropical disease: a systematic review

BACKGROUND

Neglected tropical diseases (NTDs) are diseases of poverty and affect 1·5 billion people globally. Conditional cash transfer (CCTs) programmes alleviate poverty in many countries, potentially contributing to improved NTD outcomes. This systematic review examines the relationship between CCTs and screening, incidence, or treatment outcomes of NTDs.

METHODS

In this systematic review we searched MEDLINE, Embase, Lilacs, EconLit, Global Health, and grey literature websites on Sept 17, 2020, with no date or language restrictions. Controlled quantitative studies including randomised controlled trials (RCTs) and observational studies evaluating CCT interventions in low-income and middle-income countries were included. Any outcome measures related to WHO's 20 diseases classified as NTDs were included. Studies from high-income countries were excluded. Two authors (AA and TH) extracted data from published studies and appraised risk of biases using the Risk of Bias in Non-Randomised Studies of Interventions and Risk of Bias 2 tools. Results were analysed narratively. This study is registered with PROSPERO, CRD42020202480.

FINDINGS

From the search, 5165 records were identified; of these, 11 studies were eligible for inclusion covering four CCTs in Brazil, the Philippines, Mexico, and Zambia. Most studies were either RCTs or quasi-experimental studies and ten were assessed to be of moderate quality. Seven studies reported improved NTD outcomes associated with CCTs, in particular, reduced incidence of leprosy and increased uptake of deworming treatments. There was some evidence of greater benefit of CCTS in lower socioeconomic groups but subgroup analysis was scarce. Methodological weaknesses include self-reported outcomes, missing data, improper randomisation, and differences between CCT and comparator populations in observational studies. The available evidence is currently limited, covering a small proportion of CCTs and NTDs.

INTERPRETATION

CCTs can be associated with improved NTD outcomes, and could be driven by both improvements in living standards from cash benefits and direct health effects from conditionalities related to health-care use. This evidence adds to the knowledge of health-improving effects from CCTs in poor and vulnerable populations.

FUNDING

None.

Family-based intervention for prevention and self-management of disabilities due to leprosy, podoconiosis and lymphatic filariasis versus usual care in Ethiopia: study protocol for a cluster-randomised controlled trial

INTRODUCTION

Leprosy, podoconiosis and lymphatic filariasis (LF) are three skin-related neglected tropical diseases. All three conditions can lead to temporary and permanent impairments. These impairments progressively worsen and are major determinants of stigma, discrimination and participation restrictions. Self-care is essential to prevent disabilities and chronic disease complications. Many persons with leprosy-related, LF-related and podoconiosis-related disabilities need to practice self-management routines their entire life. This is difficult without support and encouragement of others. The objective of this study was to assess the effectiveness of a family-based intervention in terms of physical outcomes related to prevention and self-management of disabilities due to leprosy, podoconiosis and LF and family quality of life and well-being compared with usual practice and care.

METHODS AND ANALYSIS

The study will use a cluster-randomised controlled trial design with two study arms. The project will be carried out in endemic districts in East and West Gojjam zones in the Amhara region in Ethiopia. Clusters consist of kebeles (lower administrative structures in the district) that have been merged, based on their geographical proximity and the number of cases in each kebele. A total of 630 participants will be included in the study. The intervention group will consist of 105 persons affected by leprosy, 105 persons affected by LF or podoconiosis, and 210 family members. The control group will consist of 105 persons affected by leprosy and 105 persons affected by LF or podoconiosis. The family-based intervention comprises an essential care package that consists of the following three main components: (1) self-management of disabilities, (2) economic empowerment and (3) psychosocial support. Participants in the control areas will receive usual practice and care. Data analysis includes, but is not limited to, calculating the percentage of change and corresponding 95% CI of physical impairment outcomes in each group, before and after the intervention is implemented, effect sizes, intention to treat and difference in difference analysis.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Debre Markos University Health Sciences Institutional Research Ethics Review Committee. Results will be disseminated through peer-reviewed publications, conference presentations and workshops.

TRIAL REGISTRATION NUMBER

PACTR202108907851342.

Potential molecular targets of Leishmania pathways in developing novel antileishmanials

The illness known as leishmaniasis has not become a household name like malaria, although it stands as the second-largest parasitic disease, surpassed only by malaria. As no licensed vaccine is available, treatment for leishmaniasis mostly relies on chemotherapy. Inefficiency and drug resistance are the major impediments in current therapeutics. In this scenario, identification of novel molecular drug candidates is indispensable to develop robust antileishmanials. The exploration of structure-based drugs to target enzymes/molecules of Leishmania which differ structurally/functionally from their equivalents in mammalian hosts not only helps in developing a new class of antileishmanials, but also paves the way to understand Leishmania biology. This review provides a comprehensive overview on possible drug candidates relating to various Leishmania molecular pathways.

Effectiveness of self-care interventions for integrated morbidity management of skin neglected tropical diseases in Anambra State, Nigeria

Background

Lymphatic filariasis (LF), Buruli ulcer (BU) and leprosy are neglected tropical diseases (NTDs) of the skin co-endemic in some communities in Nigeria. Not enough is known about the effectiveness of integrated morbidity management and disability prevention in people with these conditions. An integrated self-care intervention was carried out for people with these skin NTDs in two endemic communities of Anambra state, Nigeria. The objective of the study was to assess the effectiveness of self-care practices on costs of care, disability status and health-related quality of life.

Methods

This study utilised a quasi-experimental pre-test/post-test design to assess the effectiveness of the self-care interventions for people affected by NTDs to care for these impairments at home. Data were collected using questionnaires administered at the beginning and at the end of the intervention on monthly cost of morbidity care, and on participants’ disability status and their quality of life (QoL). Focus group discussions (FGDs) were held with both the participants and healthcare workers at follow-up.

Results

Forty-eight participants were recruited. Thirty participants (62.5%) continued the self-care interventions until the end of the project. Of those, 25 (83%) demonstrated improvement from their baseline impairment status. The mean household costs of morbidity care per participant decreased by 66% after the intervention, falling from US$157.50 at baseline to US$53.24 after 6 months of self-care (p = 0.004). The mean disability score at baseline was 22.3; this decreased to 12.5 after 6 months of self-care (p < 0.001). Among the 30 participants who continued the interventions until the end of the project, 26 (86.7%) had severe disability score (i.e. a score of 10–46) at baseline, and the number with severe disability fell to 18 (60%) of the 30 after the intervention. The mean QoL score increased from 45.7 at baseline to 57.5 at the end of the intervention (p = 0.004).

Conclusions

The 6-month self-care intervention for participants affected by BU, leprosy, or LF led to lower costs of care (including out-of-pocket costs and lost earnings due to morbidity), improved QoL scores, and reduced disability status.

Trial registration

ISRCTN Registry: ISRCTN20317241; 27/08/2021, Retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11729-1.

The history of the neglected tropical disease movement

The history of the neglected tropical disease movement is seen through the lens of authors who worked during the last 4 decades in different roles and in different settings, from Western-based laboratories to clinical roles in endemic countries and in critical policy roles in the World Health Organization (WHO). The authors seek to identify key players from the introduction of the word 'neglected' by the late Kenneth Warren in his Rockefeller Foundation-supported Great Neglected Diseases of Mankind movement through to the more recent developments after the London Declaration of 2012. The role of the various actors-endemic countries, major pharmaceutical companies, the WHO, non-government development organizations, bilateral donors and academia-are discussed. The critical events and decisions are highlighted that were essential enabling factors in creating a viable and successful movement and with a resultant massive global public health and antipoverty impact. The importance of advocacy is emphasized in creating the momentum to establish a globally recognized public health 'brand' as a target in the United Nations Sustainable Development Goals.

Risk factors and prevalence of taeniasis among the Karen people of Tha Song Yang District, Tak Province, Thailand

Taeniasis remains a prevalent public health problem in Thailand. National helminthiasis surveys report only the incidence of Taenia spp. eggs. The ability to differentiate Taenia species using morphological and molecular techniques is vital for epidemiological surveys. This study detected taeniasis carriers and other helminthic infections by Kato's thick smear technique and identified the Taenia species by multiplex PCR. The study subjects were the ethnic Karen people in Tha Song Yang District, Tak Province, Thailand, bordering Myanmar. In total, 983 faecal samples from villagers were examined for helminthiases. Interview-based questionnaires were used to gather information on possible risk factors for infection. The prevalence of helminth infections was 42.7% (420/983), including single (37.3%, 367/983) and mixed infections (5.4%, 53/983). The most common infection (19.23%, 189/983) was Ascaris lumbricoides, whereas taeniasis carriers comprised 2.8% (28/983). Multiplex PCR of Cox1 was used for species identification of Taenia tapeworms, eggs, or both in 22 taeniasis carriers. Most of the parasites (20 cases) were Taenia solium, with two cases of Taenia saginata. Taenia saginata asiatica was not found in the villagers examined. The analysis of 314 completed questionnaires showed that a statistically significant (p < 0.05) risk of taeniasis was correlated with being male, a history of being allowed to forage during childhood, a history of seeing tapeworm proglottids, and a history of raw or undercooked pork consumption. Health education programmes must seek to reduce and prevent reinfection in these communities.

The Top 100 Cited Papers in the Field of Iron Deficiency in Humans: A Bibliometric Study

Worldwide, iron deficiency is a common form of micronutrient deficiency with a high individual and societal cost. There are considerable knowledge and practice gaps in the diagnosis and treatment of iron deficiency. Bibliometric analysis examines the published body of knowledge of a subject in an objective fashion. The Web of Science Core Collection was searched to retrieve the 100 most cited papers on the topic of iron deficiency, and the key metrics of each paper were extracted. A keyword study was performed using VOSviewer 1.6.10 software, which provided a visual mapping of the network of keyword cooccurrences. The papers were published between 1964 and 2017 and were cited an average of 636 times. They were contributed by authors from 119 different countries/regions, with the largest contributing country being the United States. 29 institutions contributed at least 6 publications each, and 4 researchers authored or coauthored at least 5 papers. Keyword analysis suggests that the most cited topics could be grouped into 4 categories: (1) epidemiologic research of the global burden of iron deficiency, (2) clinical aspects of iron deficiency anemia, (3) iron metabolism, and (4) the impact of iron deficiency on children. Identification of the most impactful studies in the field of iron deficiency may be helpful to practitioners interested in improving their knowledge base. Compared to bibliometric studies performed on other topics, the medical literature of iron deficiency is mature, as evidenced by the high citation rate of the top 100 papers. Despite the high worldwide prevalence of iron deficiency, the top cited papers are dominated by a relatively small number of countries and institutions. Interestingly, however, the most cited authors in this study do not overlap with the most cited institutions.

Anti-trypanosomal and anthelminthic properties of ethanol and aqueous extracts of Tetrapleura tetraptera Taub

Trypanosomosis and helminthosis, considered as part of neglected tropical diseases, are parasitic infections of public health importance, especially in Africa. Medicinal plants have been used in most parts of Africa, to treat these parasitic infections. The study aims to determine the anti-trypanosomal and anthelminthic properties of Tetrapleura tetraptera (fruit and stembark). The aqueous extracts of T. tetraptera fruit (TTFaq) and stembark (TTSaq), as well as ethanol extracts of T. tetraptera fruit (TTFe) and stembark (TTSe), were screened for their in vitro anti-trypanosomal and anthelminthic activities against T. b. brucei and Pheretima posthuma worms, respectively. Preliminary phytochemical screening of all extracts and gas chromatography-mass spectrometry (GC-MS) analysis of most active extracts were conducted. TTFaq exhibited anti-trypanosomal activity with IC₅₀ of 18.18 μg/mL. TTSe and TTFe had moderate anti-trypanosomal activity with IC₅₀ of 34.76 and 34.84 μg/mL, respectively. TTSaq had relatively low activity against the parasite with IC₅₀ of 55.03 μg/mL. The SI of T. tetraptera extracts was between the range of 0.14-2.09. TTFaq showed dose-dependent activity causing paralysis and death of the adult worms at all concentrations. At the least concentration of 0.625 mg/mL, TTFaq induced paralysis and death after 101.88 ± 0.8 and 242.64 ± 0.38 min of exposure, respectively compared with the negative control (p < 0.0001). TTFe, TTSe and TTSaq caused paralysis of worms after 318.32 ± 0.74, 422.5 ± 0.72, 422.20 ± 0.55 min of exposure at minimum concentrations of 2.5, 10 and 5 mg/mL, respectively (p < 0.0001). However, no death was observed in worms treated with TTFe, TTSe and TTSaq at all test concentrations. In the presence of sub-minimal inhibitory concentration of the extracts, TTFaq potentiated the anthelminthic activity of albendazole whiles TTFe, TTSaq and TTSe inhibited the activity of albendazole. Phytochemical screening revealed the presence of saponins, triterpenoids, reducing sugars, flavonoids (absent in TTFe), steroids (absent in TTFaq) and tannins (absent in TTSe and TTFe) in the extracts. GC-MS revealed the presence of 9-octadecenamide and betulic acid in TTFaq. Hence, there was evidence provided here that Tetrapleura tetraptera may be effective. This gives credence to their folkloric use. However, further study might be necessary to ascertain safety use in both humans and animals.

Practices in research, surveillance and control of neglected tropical diseases by One Health approaches: A survey targeting scientists from French-speaking countries

One health (OH) approaches have increasingly been used in the last decade in the fight against zoonotic neglected tropical diseases (NTDs). However, descriptions of such collaborations between the human, animal and environmental health sectors are still limited for French-speaking tropical countries. The objective of the current survey was to explore the diversity of OH experiences applied to research, surveillance and control of NTDs by scientists from French-speaking countries, and discuss their constraints and benefits. Six zoonotic NTDs were targeted: echinococcoses, trypanosomiases, leishmaniases, rabies, Taenia solium cysticercosis and leptospiroses. Invitations to fill in an online questionnaire were sent to members of francophone networks on NTDs and other tropical diseases. Results from the questionnaire were discussed during an international workshop in October 2019. The vast majority (98%) of the 171 respondents considered OH approaches relevant although only 64% had implemented them. Among respondents with OH experience, 58% had encountered difficulties mainly related to a lack of knowledge, interest and support for OH approaches by funding agencies, policy-makers, communities and researchers. Silos between disciplines and health sectors were still strong at both scientific and operational levels. Benefits were reported by 94% of respondents with OH experience, including increased intellectual stimulation, stronger collaborations, higher impact and cost-efficiency of interventions. Recommendations for OH uptake included advocacy, capacity-building, dedicated funding, and higher communities' involvement. Improved research coordination by NTD networks, production of combined human-animal health NTD impact indicators, and transversal research projects on diagnostic and reservoirs were also considered essential.

Easy-To-Access Quinolone Derivatives Exhibiting Antibacterial and Anti-Parasitic Activities

The cell wall of Mycobacterium tuberculosis (Mtb) has a unique structural organisation, comprising a high lipid content mixed with polysaccharides. This makes cell wall a formidable barrier impermeable to hydrophilic agents. In addition, during host infection, Mtb resides in macrophages within avascular necrotic granulomas and cavities, which shield the bacterium from the action of most antibiotics. To overcome these protective barriers, a new class of anti-TB agents exhibiting lipophilic character have been recommended by various reports in literature. Herein, a series of lipophilic heterocyclic quinolone compounds was synthesised and evaluated in vitro against pMSp12::GFP strain of Mtb, two protozoan parasites (Plasmodium falciparum and Trypanosoma brucei brucei) and against ESKAPE pathogens. The resultant compounds exhibited varied anti-Mtb activity with MIC₉₀ values in the range of 0.24–31 µM. Cross-screening against P. falciparum and T.b. brucei, identified several compounds with antiprotozoal activities in the range of 0.4–20 µM. Compounds were generally inactive against ESKAPE pathogens, with only compounds 8c, 8g and 13 exhibiting moderate to poor activity against S. aureus and A. baumannii.

The Elimination of Neglected Tropical Diseases: A Case Study Exemplifying How Foreign Assistance Funding Can Be Catalytic in Reducing the Burden of Major Global Health Conditions

In 2006, following direct advocacy and published rationale, the US Agency for International Development (USAID) established a neglected tropical diseases (NTDs) program to support the scale-up of integrated platforms to target the elimination and control of 5 NTDs-lymphatic filariasis, trachoma, onchocerciasis, schistosomiasis, and soil-transmitted helminthiasis. By 2017, more than 2.3 billion NTD treatments had been delivered to at-risk populations in 25 countries, leveraging $19 billion in donated drugs-approximately $26 dollars in donated medicine per $1 spent by USAID. As a result, most of the supported countries are on track to achieve their elimination goals (for lymphatic filariasis and trachoma) by 2020 or 2021 and their control goals soon thereafter. Though "small" when compared to other global health initiatives, this investment proved to be catalytic, and indeed highlights how foreign assistance funding can be transformative, in reducing the burden of major global health conditions such as NTDs.

Efforts to mitigate the economic impact of the COVID-19 pandemic: potential entry points for neglected tropical diseases

Background

The damage inflicted by the coronavirus diseases 2019 (COVID-19) pandemic upon humanity is and will continue to be considerable. Unprecedented progress made in global health over the past 20 years has reverted and economic growth has already evaporated, giving rise to a global recession, the likes of which we may not have experienced since the Second World War. Our aim is to draw the attention of the neglected tropical disease (NTD) community towards some of the major emerging economic opportunities which are quickly appearing on the horizon as a result of COVID-19.

Main text

This scoping review relied on a literature search comprised of a sample of articles, statements, and press releases on initiatives aimed at mitigating the impact of COVID-19, while supporting economic recovery. Of note, the donor scenario and economic development agendas are highly dynamic and expected to change rapidly as the COVID-19 pandemic unfolds, as are donor and lender priorities.

Conclusions

The NTD community, particularly in low- and middle-income countries (LMICs), will need to work quickly, diligently, and in close collaboration with decision-makers and key stakeholders, across sectors at national and international level to secure its position. Doing so might enhance the odds of grasping potential opportunities to access some of the massive resources that are now available in the form of contributions from corporate foundations, trust funds, loans, debt relieve schemes, and other financial mechanisms, as part of the ongoing and future economic development agendas and public health priorities driven by the COVID-19 pandemic. This paper should serve as a starting point for the NTD community to seek much needed financial support in order to sustain and revitalize control and elimination efforts pertaining to NTDs in LMICs.

A school-based soil-transmitted helminths survey in the Guadalcanal Province, the Solomon Islands

Infections by soil-transmitted helminths are a major public health problem worldwide, especially among schoolchildren in low-income countries. Little information is described about their prevalence in the Solomon Islands. From 2017 to 2018, a school-based soil-transmitted helminths survey in the Guadalcanal Province was conducted. A total of 454 schoolchildren were selected; the Merthiolate-iodine-formaldehyde concentration and stain was used. The prevalence was 17% of one or more parasites, including hookworm (8.8%), Strongyloides stercoralis (5.7%), Ascaris lumbricoides (4.2%) and Trichuris trichiura (3.5%). STH infection was significantly correlated with parents' occupations, hand washing, shoe wearing as well as gastrointestinal symptoms. To prevent STH transmission for schoolchildren in the Solomon Islands completely, combined preventive strategies seem necessary.

COVID-19 and the Antipoverty Vaccines

The number of global COVID19 cases has just exceeded 15 million, and there is mounting evidence for a devastating economic impact from this illness. Although COVID19 affected primarily China, Europe, and North America during the first half of 2020, now this disease is accelerating in the resource-poor nations of the Global South. Across Latin America, South Asia, and Africa, COVID19 is expected to push up to 100 million people into extreme poverty, eroding many of the economic gains achieved over the last five years. COVID19 vaccines will be required to help control the pandemic, especially in low- and middle-income nations. These will have important health benefits, but might also prevent further economic devastation. The term “antipoverty vaccines” has been used to refer to vaccines to prevent neglected tropical diseases that affect worker productivity, child development, and the health of girls and women. COVID19 vaccines could also become important antipoverty technologies provided we find ways to scale and distribute them as affordable vaccines. Two vaccines now being accelerated for global health include whole inactivated virus and recombinant protein vaccines. These might become essential tools for combating global poverty.

The process of building the priority of neglected tropical diseases: A global policy analysis

The global burden attributed to Neglected Tropical Diseases (NTDs) is 47.9 million Disability-Adjusted Life Years (DALYs). These diseases predominantly affect disadvantaged populations. Priority for NTDs has grown in recent years, which is observed by their inclusion in the sustainable development goals (SDGs). This study analyzed the process that allowed these diseases to be included on the global health policy agenda. This global policy analysis used the Shiffman and Smith framework to understand the determinants of global health political priority for NTDs. The framework comprises four categories: actor power, ideas, political contexts, and issue characteristics. Global documents and World Health Assembly (WHA) resolutions were examined, key-informant interviews were conducted, and academic publications were reviewed to understand the four categories that comprise the framework. A total of 37 global policy documents, 15 WHA resolutions, and 38 academic publications were examined. Twelve semi-structured interviews were conducted with individuals representing different sectors within the NTD community who have been involved in raising the priority of these diseases. This study found that several factors helped better position NTDs in the global health agenda. These include the leadership of actors that mobilized the global health community, the creation of a label combining these diseases as a group to represent a larger disease burden, the presence of mechanisms aligning the NTD community, and the agreement on ways to present the NTD burden and potential solutions. The process of building the priority of NTDs in the global health agenda shows that several determinants led to positive outcomes, but these diseases continue to have low priority at the global level which requires the implementation of actions to increase their global priority. These include sustaining the commitment of current actors and engaging new ones; increasing the attention given to diseases formerly categorized as "tool-deficient", including zoonotic NTDs; continue leveraging on policy windows and creating favorable policy moments to sustain commitment, as well as setting realistic targets. Findings from this study can help develop strategies to build the momentum and drive actions to implement the goals of the new Roadmap for NTDs in the pathway to universal health coverage (UHC) and sustainable development.

Prevalence of dengue virus serotypes in the 2017 outbreak in Peshawar, KP, Pakistan

Background

Dengue is a viral disease, transmitted by infected Aedes aegypti and Aedes albopictus female mosquitoes. Worldwide, 96 million infections were estimated in 2010. The dengue virus comprises four distinct serotypes (DENV‐1, DENV‐2, DENV‐3, and DENV‐4) which belong to the genus Flavivirus. Determining the serotypes during dengue outbreaks is crucial for its effective management in terms of diagnostics improvement and polyvalent vaccine development. The aim of the present study is to determine the prevalence rate of dengue virus serotypes in the samples collected from patients during the 2017 outbreak in Khyber Pakhtunkhwa, Pakistan.

Methods

A total of 800 ELISA‐positive samples were collected, of which 513 (290 males, 223 females) samples were confirmed positive by PCR.

Results

Out of 513, 25 were found serotype 1 (5%), 196 were serotype 2 (38%), 192 were serotype 3 (37%), 56 were serotype 4 (11%), and 44 (8%) were found to have mix serotypes.

Conclusion

We can conclude that serotypes 2 and 3 of dengue virus were the predominated serotypes of dengue virus in the 2017 outbreak in Peshawar, capital city of Khyber Pakhtunkhwa, Pakistan.

Strategies supporting the prevention and control of neglected tropical diseases during and beyond the COVID-19 pandemic

Emerging and re-emerging zoonotic diseases represent a public health challenge of international concern. They include a large group of neglected tropical diseases (NTDs), many of which are of zoonotic nature. Coronavirus disease 2019 (COVID-19), another emerging zoonotic disease, has just increased the stakes exponentially. Most NTDs are subject to the impact of some of the very same human-related activities triggering other emerging and re-emerging diseases, including COVID-19, severe acute respiratory syndrome (SARS), bird flu and swine flu. It is conceivable that COVID-19 will exacerbate the NTDs, as it will divert much needed financial and human resources. There is considerable concern that recent progress achieved with control and elimination efforts will be reverted. Future potential strategies will need to reconsider the determinants of health in NTDs in order to galvanize efforts and come up with a comprehensive, well defined programme that will set the stage for an effective multi-sectorial approach. In this Commentary, we propose areas of potential synergies between the COVID-19 pandemic control efforts, other health and non-health sector initiatives and NTD control and elimination programmes.

Clinical and epidemiological profile of patients in the chronic phase of Chagas disease treated at a reference center in the Southeast region of Brazil

Introduction: After implementing measures to control vector transmission by Triatoma infestans in Brazil, the number of new cases of Chagas disease decreased. Currently, the American continent has an annual incidence of 28 000 cases, but there are still a large number of older adults affected by the chronic phase of this disease.Objective: To characterize the clinical and epidemiological profile of patients in the chronic phase of Chagas disease treated at a reference center of São Paulo (State), Brazil.Materials and methods: Cross-sectional, descriptive study based on the analysis of the clinical histories of 62 patients in the chronic phase of Chagas disease and treated at Hospital das Clínicas de Marília.Results: No significant differences were found regarding sex, age and time of diagnosis. Cardiac problems were the most reported symptom. A significant difference was observed in the case of the indeterminate form of the disease, which was more predominant in males. In addition, functional class B1 was more common in women, while B2 predominated in men.Conclusion: A late diagnosis of Chagas disease may increase the chances of presenting digestive symptoms. However, the classic manifestations of the disease and its comorbidities can be successfully managed as long as comprehensive (multidisciplinary) medical care is provided, since this would help delay the course of the disease and, consequently, improve the patients’ quality of life.