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1.
Sci Rep ; 13(1): 133, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36599848

RESUMO

Accurate diagnosis by precise identification of causative agents is essential for the effectiveness of any control interventions. Despite high zoonotic potential, available literature on hookworms in Bangladesh is still scarce and nonspecific. The objective of this study was to determine the occurrence of hookworms in public locations across northeastern Bangladesh (Sylhet metropolitan area) using integrated parasitological and molecular assays. A total of 130 samples (80 soil and 50 environmental canine feces) were collected and examined using modified flotation technique and formalin-ether sedimentation methods. Modified plate culture was used to isolate larvae. The identification was made based on morphometric features and confirmed by amplifying the ITS region of the nuclear rDNA. Overall, 66.2% (86/130) of examined samples were positive for hookworms infection. Characteristic eggs (61-68 × 29-37 µm) and/or larvae of hookworms were observed in 73.8% (59/80) soils and 54.0% (27/50) environmental fecal samples. Rhabditiform larvae (0.48-0.54 × 0.04-0.07 mm) were observed in cultured samples. Genetic analysis of rDNA sequences revealed the presence of Ancylostoma caninum and Ancylostoma ceylanicum. In this study, hookworms' contamination of the public environment was substantial. To the best of our knowledge, this is the first molecular proof of A. caninum and A. ceylanicum observed in urban public environment in Bangladesh.


Assuntos
Doenças do Cão , Infecções por Uncinaria , Animais , Cães , Ancylostomatoidea/genética , Bangladesh , Infecções por Uncinaria/epidemiologia , Ancylostoma/genética , Fezes , DNA Ribossômico , Solo , Larva , Doenças do Cão/epidemiologia
2.
Biomed Res Int ; 2023: 6553913, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36647545

RESUMO

Background: Soil-transmitted helminths (STHs) are parasitic worms that are widely distributed in the tropical and subtropical regions. In Ethiopia, one of the tropical countries, STH infections are high and cause a huge burden. Several STH species show a pattern of household clustering with regard to prevalence and intensity. However, there is a scarcity of data on the status of STH infection among family contacts of STH-infected individuals in Ethiopia in general and in the study area in particular. Objective: This study is aimed at assessing the prevalence of soil-transmitted helminths and associated factors among STH-infected household contacts in Burie Zuria district, northwest Ethiopia. Method: A community-based cross-sectional study was conducted among 422 study participants from March to May 2021. Study participants were traced to their residences by following STH-infected patients. A convenient sampling technique was used to recruit the study participants. The stool samples were processed using duplicate Kato-Katz thick smears and a modified Ritchie's technique. The data were entered and analyzed using the Statistical Package for Social Sciences, version 26 of the software package. A P value <0.05 was considered a statistically significant association. Results: The overall prevalence of STHs was 36.5% (95% CI: 31.7%-41.5%). Two STHs, namely hookworm species (33.2%, 140/422) at (95% CI: 28.9%-37.8%) and Ascaris lumbricoides (4.3%, 18/422) at (95% CI: 2.7%-6.6%), were identified, with a double infection of 2.6% (4/154) at (95% CI: 1.0%-6.5%). Almost the majority (96.9%) of hookworm species and all Ascaris lumbricoides infections were categorized under a light intensity of infection. Family size >5 (AOR = 1.74; 95% CI: 1.15-2.60; P = 0.008) and lack of latrine facility (AOR = 1.86; 95% CI: 1.17-2.90; P = 0.02) were significantly associated with STH infections. Conclusion: A high prevalence of hookworms was found in the study area, where the majority of the study participants were adults. This finding may provide a basis for revising the school-based deworming programs that exclude the adult population. Public health interventions like accessing latrines, health education, and deworming programs should be regularly implemented for all age groups in the areas.


Assuntos
Helmintíase , Helmintos , Animais , Ancylostomatoidea , Estudos Transversais , Solo/parasitologia , Prevalência , Etiópia/epidemiologia , Fatores de Risco , Helmintíase/epidemiologia , Fezes/parasitologia
3.
PLoS One ; 17(12): e0279754, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36584196

RESUMO

Intestinal parasitic infections (IPIs) remain a public-health problem worldwide, including in countries of the Lower Mekong subregion. Increases in human migration from neighboring countries might cause reemerging parasitic infections, leading to spread of parasites in the landscape. Here, we conducted a cross-sectional study to identify the prevalence of IPIs in migrant workers from Myanmar, Lao PDR, and Cambodia who were dwelling in Nakhon Ratchasima Province, northeastern Thailand. The identification of Strongyloides species and genetic differentiation of worms from migrant workers with different countries of origin was also assessed. Fresh stool samples were collected from 338 migrant workers and examined for evidence of IPIs using agar plate culture (APC) and the formalin-ethyl acetate concentration technique (FECT). Among those nine samples positive for nematodes by APC, the Strongyloides or hookworm species present was confirmed using the polymerase chain reaction (PCR) followed by DNA sequencing. This revealed eight cases of Strongyloides stercoralis infection and one of Necator americanus. Fifty-one out of 338 individuals (15.09%) were positive for IPIs using FECT and APC. Eggs of Opisthorchis-like flukes were the most common parasite (11.83% of samples), followed by S. stercoralis (2.37%), Entamoeba coli (1.50%), hookworm (0.89%), Taenia sp. (0.60%) and Hymenolepis nana (0.30%). The genetic differentiation of S. stercoralis recovered from migrant workers with different countries of origin was analyzed. Specimens of S. stercoralis isolated from workers from Lao PDR, Cambodia and Myanmar were genetically similar to those sequenced from Thailand. However, there were population-genetic differences between S. stercoralis from these Southeast Asian countries and other regions of the world. This study demonstrated that IPIs were prevalent in migrant workers in the northeastern region of Thailand. Our findings provided molecular confirmation of the presence of S. stercoralis and explored the genetic differentiation of S. stercoralis from those infected migrant workers. An effective anti-parasitic drug should be provided for migrant workers and its administration enforced.


Assuntos
Infecções por Uncinaria , Enteropatias Parasitárias , Parasitos , Strongyloides stercoralis , Estrongiloidíase , Migrantes , Humanos , Animais , Tailândia/epidemiologia , Camboja/epidemiologia , Prevalência , Laos/epidemiologia , Mianmar/epidemiologia , Estudos Transversais , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Estrongiloidíase/epidemiologia , Estrongiloidíase/parasitologia , Infecções por Uncinaria/epidemiologia , Ancylostomatoidea , Fezes/parasitologia
4.
Parasit Vectors ; 15(1): 410, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333779

RESUMO

BACKGROUND: The Geshiyaro project is a 5-year intervention to assess the impact of community- and school-based water, sanitation, and hygiene (WaSH) interventions on reducing infection with soil-transmitted helminths (STH) and schistosome parasites in combination with deworming in Wolayita zone, Ethiopia. METHODS: A population-based, cross-sectional census and parasitological mapping activity was conducted between 2018 and 2019. Individuals in the census were identified using either a registered study ID card or biometric fingerprint to enable linkage of their household WaSH data with baseline STH and schistosome prevalence for risk analysis. RESULTS: Prevalence of STH was 15.5% for any STH species, 9.47% for Ascaris lumbricoides, 1.78% for Trichuris trichiura, and 7.24% for hookworm. Intestinal schistosomiasis (Schistosoma mansoni) infection prevalence was 0.85% by Kato Katz, 21.6% by POC-CCA trace positive (Tr +), and 13.3% trace negative (Tr-). Microhaematuria was 2.77%, with 0.13% of people examined with S. haematobium eggs detected by urine filtration. At the household level, increased (> 30 min) time taken to collect drinking water, sharing a latrine, and lack of handwashing facilities were all associated with a greater risk of A. lumbricoides, hookworm, and S. mansoni infection. Not disposing of infant stool at the household and clothes washing/recreational freshwater contact were significantly associated with higher risk of schistosomiasis infection. Aggregating WaSH data at the community level showed odds of A. lumbricoides, hookworm, and T. trichiura infection were significantly lower as both community sanitation coverage and access to improved drinking water improved. CONCLUSIONS: The principal finding of this study is that lack of access to WaSH, such as improved drinking water and shared toilet and hand-washing facilities, were linked to an increased risk of infection with STH and schistosome parasites. These associations are difficult to establish at an individual household level because of wide variability in access between houses but are detectable when coverage is aggregated at the community level. Maintenance of WaSH facilities as well as increased access within the whole community is important in influencing the community-wide prevalence of infection with STH and schistosome parasites.


Assuntos
Água Potável , Helmintíase , Helmintos , Infecções por Uncinaria , Schistosomatidae , Lactente , Animais , Humanos , Saneamento , Solo/parasitologia , Prevalência , Estudos Transversais , Etiópia/epidemiologia , Higiene , Infecções por Uncinaria/epidemiologia , Ancylostomatoidea , Schistosoma mansoni , Fezes/parasitologia , Helmintíase/epidemiologia
5.
Front Immunol ; 13: 1009968, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330509

RESUMO

Helminth infection-driven changes to immunity in the female reproductive tract (FRT) is an immune axis that is currently understudied but can have major implications for the control of FRT infections. Here we address how human hookworm infection associates with vaginal immune profile and risk of Human papillomavirus (HPV) infection. Stool, blood, cervical swabs and vaginal flushes were collected from women from the Central region of Togo to screen for hookworms (Ancylostoma duodenale) and high carcinogenic risk HPV types, via Kato Katz and PCR, respectively. Cytokine, chemokine and immunoglobulin levels were analysed in cervicovaginal lavages and plasma samples. A pronounced mixed Type 1/Type 2 immune response was detected in the vaginal fluids of women with hookworm infection and this immune signature was a notable feature in hookworm-HPV co-infected women. Moreover, hookworm infection is positively associated with increased risk and load of HPV infection. These findings highlight helminth infection as a significant risk factor for acquiring a sexually transmitted viral infection and potentially raising the risk of subsequent pathology.


Assuntos
Helmintíase , Infecções por Uncinaria , Infecções por Papillomavirus , Infecções do Sistema Genital , Animais , Feminino , Humanos , Infecções por Papillomavirus/complicações , Vagina , Ancylostomatoidea
6.
PLoS Negl Trop Dis ; 16(10): e0010767, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36315591

RESUMO

Preventive chemotherapy (PC), consisting of the regular distribution of anthelmintics to populations or groups of populations at risk, is the primary tool used to control soil-transmitted helminth (STH) infections. This strategy, whilst cost-effective, raises the concern of potential emergence of drug resistance. The efficacy of anthelmintics against STH infections is measured using cure rate (CR) and egg reduction rate (ERR), using microscopy-based techniques such as the Kato-Katz thick smear. However, Kato-Katz has low sensitivity, especially for low-intensity infections, and requires fresh samples that need to be processed quickly. Realtime quantitative PCR (qPCR), which is more sensitive, is emerging as a "gold standard" for STH diagnostics given its higher sensitivity (important in low prevalence settings) and ability to differentiate hookworm species, while sodium nitrate flotation (SNF) may provide a low-cost more sensitive and practical alternative to Kato-Katz in the field. In this study, we examined the efficacy of a locally manufactured brand of albendazole 400 mg ("Alzental") against hookworm in Dak Lak province, Vietnam, using both qPCR and SNF. For qPCR, formulae to convert qPCR cycle threshold (Ct) values into eggs per gram of faeces (EPG) were utilised to determine efficacy calculations, and these values directly compared with efficacy values generated using SNF. Factors associated with CR and ERR were examined, and Alzental tablet quality was assessed by comparing with an Australian TGA-approved equivalent "Eskazole" tablet. We observed a CR and ERR of 64.9% and 87.5% respectively using qPCR, and 68.4% and 67.6% respectively using SNF. The tablet composition of Alzental was comparable to Eskazole in terms of active albendazole drug concentration with no evidence of impurities. This study demonstrates that the efficacy of Alzental against hookworm is within the range of previously reported studies for albendazole 400 mg. The study also demonstrates the value of qPCR and SNF as alternatives to standard Kato-Katz methodology for assessment of anthelmintic efficacy.


Assuntos
Anti-Helmínticos , Helmintíase , Infecções por Uncinaria , Animais , Ancylostomatoidea/genética , Albendazol/farmacologia , Albendazol/uso terapêutico , Vietnã , Austrália , Infecções por Uncinaria/tratamento farmacológico , Infecções por Uncinaria/epidemiologia , Helmintíase/epidemiologia , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Reação em Cadeia da Polimerase em Tempo Real , Fezes , Solo
7.
PLoS Negl Trop Dis ; 16(10): e0010895, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36279298

RESUMO

Soil-transmitted helminths (STH) infect 1.5 billion people and countless animals worldwide. In Australian Indigenous communities, STH infections have largely remained endemic despite control efforts, suggesting reservoirs of infection may exist. Dogs fulfil various important cultural, social and occupational roles in Australian Indigenous communities and are populous in these settings. Dogs may also harbour zoonotic STHs capable of producing morbidity and mortality in dogs and humans. This review provides an overview of human and zoonotic STH infections, identifies the Australian Indigenous locations affected and the parasite species and hosts involved. The meta-analysis provides estimates of individual study and pooled true prevalence of STH infections in Australian Indigenous communities and identifies knowledge gaps for further research on zoonotic or anthroponotic potential. A systematic literature search identified 45 eligible studies documenting the presence of Strongyloides stercoralis, Trichuris trichiura, Ancylostoma caninum, Ancylostoma duodenale, Ancylostoma ceylanicum, undifferentiated hookworm, and Ascaris lumbricoides. Of these studies, 26 were also eligible for inclusion in meta-analysis to establish true prevalence in the light of imperfect diagnostic test sensitivity and specificity by Rogan-Gladen and Bayesian methods. These studies revealed pooled true prevalence estimates of 18.9% (95% CI 15.8-22.1) for human and canine S. stercoralis infections and 77.3% (95% CI 63.7-91.0) for canine A. caninum infections indicating continued endemicity, but considerably more heterogenous pooled estimates for canine A. ceylanicum infections, and A. duodenale, undifferentiated hookworm and T. trichiura in humans. This review suggests that the prevalence of STHs in Australian Indigenous communities has likely been underestimated, principally based on imperfect diagnostic tests. Potential misclassification of hookworm species in humans and dogs due to outdated methodology, also obscures this picture. High-quality contemporary studies are required to establish current true prevalence of parasite species in all relevant hosts to guide future policy development and control decisions under a culturally sound One Health framework.


Assuntos
Helmintíase , Helmintos , Infecções por Uncinaria , Humanos , Cães , Animais , Solo/parasitologia , Teorema de Bayes , Austrália/epidemiologia , Ascaris lumbricoides , Trichuris , Helmintíase/epidemiologia , Infecções por Uncinaria/epidemiologia , Infecções por Uncinaria/veterinária , Ancylostomatoidea , Ancylostoma , Zoonoses/epidemiologia , Prevalência , Fezes/parasitologia
8.
PLoS One ; 17(10): e0276137, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36251667

RESUMO

Soil-transmitted helminths (STH) is a term used to refer to infections caused by intestinal worms mainly due to A. lumbricoides, T. trichiura, and hookworm species which are transmitted through contaminated soil. This study was conducted to assess the prevalence and intensity of STHs infection among individual members living within the selected household heads (HHs) certified either as a model HHs or non-model HHs based on the implementation level of a training program known as the Health Extension Program (HEP). A community-based comparative cross-sectional study was conducted from April to June 2018 at Seka Chekorsa Woreda, Jimma zone. Model and non-model HHs were selected systematically from each of the randomly selected district villages employing a multistage sampling technique. Sociodemographic and risk factors data associated with STHs infections were collected using a pre-tested structured questionnaire. Parasitological stool sample microscopic examination was done using saline wet mount and Kato Katz thick smear technique. Data analysis was performed using SPSS software version 20 for descriptive statistics, comparison, and logistic regression at a p-value < 0.05 for statistical significance. Overall, 612 individuals were recruited in the study from 120 randomly selected HHs. The prevalence of STHs infections was found to be 32.4%. A total of 45 (14.7%) model and 153 (50.0%) non-model individual participants were positive for at least one species of STHs showing a significant difference between individuals in model and non-model HHs (AOR: 6.543, 95% CI; 4.36-9.82, P<0.001). The dominant STHs were T. trichiura (21.6%) followed by A. lumbricoides (6.4%) and hookworms (2.3%). The intensity of T. trichiura and A. lumbricoides infection have shown a significant difference (p<0.05) while hookworm species infection was not significantly different (p>0.05) for the individuals in the HHs groups. On the other hand, the households training status, age of participants, and latrine use pattern were found significant predictors of STHs infection prevalence in the multivariate analysis (P<0.05). Therefore, the prevalence and intensity of STHs infection was higher among individuals living in a non-model HHs than model HHs.


Assuntos
Helmintíase , Helmintos , Infecções por Uncinaria , Ancylostomatoidea , Animais , Estudos Transversais , Etiópia/epidemiologia , Características da Família , Fezes/parasitologia , Helmintíase/epidemiologia , Helmintíase/parasitologia , Prevalência , Solo/parasitologia
9.
PLoS Negl Trop Dis ; 16(10): e0010810, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36194622

RESUMO

BACKGROUND: Hookworm infections, caused by Ancylostoma duodenale and Necator americanus, are of considerable public health importance. The World Health Organization recommends preventive chemotherapy as the key strategy for morbidity control. Meta-analyses have been conducted to estimate treatment efficacy of available drugs and drug combinations. However, in most studies, the relation between the diagnostic error and infection intensity have not been considered, resulting in an overestimation of cure rates (CRs). METHODOLOGY: A Bayesian model was developed to compare the 'true' CR and egg reduction rate of different treatment regimens for hookworm infections taking into account the error of the recommended Kato-Katz thick smear diagnostic technique. It was fitted to the observed egg count data which was linked to the distribution of worms, considered the day-to-day variation of hookworm egg excretion and estimated the infection intensity-dependent sensitivity. The CR was obtained by defining the prevalence of infection at follow-up as the probability of having at least one fertilized female worm. The model was applied to individual-level egg count data available from 17 treatments and six clinical trials. PRINCIPAL FINDINGS: Taking the diagnostic error into account resulted in considerably lower CRs than previously reported. Overall, of all treatments analyzed, mebendazole administered in six dosages of 100 mg each was the most efficacious treatment with a CR of 88% (95% Bayesian credible interval: 79-95%). Furthermore, diagnostic sensitivity varied with the infection intensity and sampling effort. For an infection intensity of 50 eggs per gram of stool, the sensitivity is close to 60%; for two Kato-Katz thick smears it increased to approximately 76%. CONCLUSIONS/SIGNIFICANCE: Our model-based estimates provide the true efficacy of different treatment regimens against hookworm infection taking into account the diagnostic error of the Kato-Katz method. Estimates of the diagnostic sensitivity for different number of stool samples and thick smears are obtained. To accurately assess efficacy in clinical trials with the Kato-Katz method, at least two stool samples on consecutive days should be collected.


Assuntos
Ancylostomatoidea , Infecções por Uncinaria , Animais , Feminino , Humanos , Contagem de Ovos de Parasitas/métodos , Mebendazol/uso terapêutico , Teorema de Bayes , Infecções por Uncinaria/diagnóstico , Infecções por Uncinaria/tratamento farmacológico , Fezes , Erros de Diagnóstico , Sensibilidade e Especificidade
10.
PLoS Negl Trop Dis ; 16(9): e0010321, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36178964

RESUMO

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.


Assuntos
Helmintíase , Helmintos , Malária Falciparum , Malária , África ao Sul do Saara/epidemiologia , Ancylostomatoidea , Animais , Criança , Fezes/parasitologia , Helmintíase/parasitologia , Humanos , Malária/complicações , Malária/epidemiologia , Malária Falciparum/epidemiologia , Prevalência , Solo/parasitologia
11.
Front Immunol ; 13: 979491, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091065

RESUMO

Hookworms infect more that 400 million people and cause significant socio-economic burden on endemic countries. The lack of efficient vaccines and the emergence of anthelminthic drug resistance are of major concern. Free-living hookworm larvae infect their hosts via the skin and live as adult worms in the small intestine where they feed on host tissue and blood. Excretory/secretory (E/S) products, released by helminths as they migrate through their host, are thought to play a key role in facilitating infection and successful establishment of parasitism. However, E/S products can also elicit protective immune responses that might be harnessed for vaccine development. By performing Western blots with serum of Nippostrongylus brasiliensis (Nb) infected mice as a model for human hookworm infection, we identified a largely overlapping set of IgG1- and IgE-reactive antigens in E/S from infective L3 stage larvae. Mass spectrometry analysis led to the identification of a new protein family with 6 paralogues in the Nb genome which we termed Nb-LSA1 for "Nippostrongylus brasiliensis larval secreted protein 1". The recombinantly expressed 17 kDa family member Nb-LSA1a was recognized by antibodies in the serum of Nb immune mice. Immunization of mice with Nb-LSA1a in alum elicited a strong IgG1 response but no detectable antigen-specific IgE. Most importantly, immunized mice were largely protected against a challenge Nb infection. This effect was dependent on the presence of basophils and occurred before the parasites reached the intestine. Therefore, basophils appear to play a critical role for rapid control of infection with L3 stage larvae in mice immunized with a single secreted larval protein. A better understanding of basophil-mediated protective immunity and identification of potent larval antigens of human hookworms could help to develop promising vaccination strategies.


Assuntos
Antígenos de Helmintos , Basófilos , Ancylostomatoidea , Animais , Humanos , Imunoglobulina E , Imunoglobulina G , Larva , Camundongos , Nippostrongylus
12.
Front Immunol ; 13: 979727, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36159869

RESUMO

Background: Malaria and helminthic parasites are endemic in tropical countries, and co-infections might influence host-parasite interactions. In this community-based cross-sectional study, the effect that the presence of soil-transmitted helminths (STH) (Hookworm, Hymenolepis nana) and Schistosoma haematobium infections could have on the immunoglobulin (Ig) candidate protein of the malaria vaccine GMZ2 levels was evaluated. Methods: Blood, stool, and urine samples were collected from 5-15-year-old children to diagnose P. falciparum (Pf), STH, and Schistosoma haematobium, respectively. Identification and quantification of the parasite load of STH and S. haematobium were achieved by light microscopy. A polymerase chain reaction was carried out to detect submicroscopic infections of P. falciparum. Plasma levels of GMZ2 specific IgG and its subclasses were quantified by ELISA. Results: The median level of total IgG in individuals with co-infection with Pf/H. nana was significantly lower in the mono-infected group with Pf (p = 0.0121) or study participants without infection (p=0.0217). Similarly, the median level of IgG1 was statistically lower in Pf/H. nana group compared to Pf-group (p=0.0137). Equally, the Pf/H. nana infected individuals posted a lower level of IgG1 compared to Pf-group (p=0.0137) and IgG4 compared to the Pf-group (p=0.0144). Spearman rank correlation analyses indicated positive relationships between the densities of H. nana (ρ=0.25, p=0.015) and S. haematobium (ρ=0.36, p<0.0001). Conclusions: Hookworm and H. nana infections are associated with reduced GMZ2 specific IgG levels. This study shows the possible manipulation of immune responses by helminths for their survival and transmission, which may have serious implications for vaccine development and deployment in helminth-endemic regions.


Assuntos
Coinfecção , Helmintos , Infecções por Uncinaria , Vacinas Antimaláricas , Malária Falciparum , Malária , Parasitos , Adolescente , Ancylostomatoidea , Animais , Criança , Pré-Escolar , Coinfecção/parasitologia , Estudos Transversais , Humanos , Imunidade , Imunoglobulina G , Nigéria/epidemiologia , Plasmodium falciparum , Solo/parasitologia
13.
Environ Int ; 169: 107521, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36148712

RESUMO

The endangered Australian sea lion, Neophoca cinerea, faces ongoing population decline. Identification of key threats to N. cinerea population recovery, including disease and pollutants, is an objective of the species' recovery plan. Previous studies have identified Uncinaria sanguinis, an intestinal nematode, as a significant cause of disease and mortality in N. cinerea pups. Given the impact of heavy metals on the immune response, investigation of these pollutants is critical. To this end, the concentrations of arsenic (As), total mercury (Hg), cadmium (Cd), chromium (Cr), lead (Pb) and selenium (Se) were determined in blood collected from N. cinerea pups sampled during the 2017/18, 2019 and 2020/21 breeding seasons at Seal Bay Conservation Park, South Australia. Significant differences (p < 0.05) in Hg, As, Cr, and Se concentrations and molar ratio of Se:Hg were seen between breeding seasons. Pup age, maternal parity and inter-individual foraging behaviour were considered factors driving these differences. The concentrations of Hg (357, 198 and 241 µg/L) and As (225, 834 and 608 µg/L) were high in 2017/18, 2019 and 2020/21 respectively with Hg concentrations in the blood of N. cinerea pups above toxicological thresholds reported for marine mammals. The concentration of Se (1332, 647, 763 µg/L) and molar ratio of Se:Hg (9.47, 7.98 and 6.82) were low compared to other pinniped pups, indicating potential vulnerability of pups to the toxic effects of Hg. Significant (p < 0.05) negative associations for Pb and Cd with several red blood cell parameters suggest they could be exacerbating the anaemia caused by hookworm disease. Temporal (age-related) changes in element concentrations were also seen, such that pup age needs to be considered when interpreting bioaccumulation patterns. Further investigation of the role of elevated heavy metal concentrations on N. cinerea pup health, disease and development is recommended, particularly with respect to immunological impacts.


Assuntos
Arsênio , Poluentes Ambientais , Infecções por Uncinaria , Intoxicação por Mercúrio , Mercúrio , Metais Pesados , Leões-Marinhos , Selênio , Ancylostomatoidea , Animais , Arsênio/toxicidade , Austrália/epidemiologia , Cádmio/toxicidade , Cromo , Feminino , Infecções por Uncinaria/epidemiologia , Chumbo , Mercúrio/toxicidade , Metais Pesados/toxicidade , Gravidez
14.
Vaccine ; 40(42): 6084-6092, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36114129

RESUMO

BACKGROUND: The Necator americanus hemoglobinase, aspartic protease-1 (Na-APR-1), facilitates the ability of adult hookworms to parasitize the intestine of their human hosts. A recombinant version of APR-1 protected laboratory animals against hookworm infection by inducing neutralizing antibodies that block the protein's enzymatic activity and thereby impair blood feeding. A catalytically inactive version of the wild-type hemoglobinase (Na-APR-1(M74)) was expressed by infiltrating Nicotiana benthamiana tobacco plants with an Agrobacterium tumefaciens strain engineered to express the vaccine antigen, which was adjuvanted with aluminum hydroxide adjuvant (Alhydrogel). METHODS: An open-label dose-escalation Phase 1 clinical trial was conducted in 40 healthy, hookworm-naïve adult volunteers in the United States. Participants received 30 or 100 µg of recombinant Na-APR-1(M74) with Alhydrogel or with Alhydrogel co-administered with one of two doses (2.5 or 5.0 µg) of an aqueous formulation of Glucopyranosyl Lipid A (GLA-AF). Intramuscular injections of study vaccine were administered on days 0, 56, and 112. RESULTS: Na-APR-1(M74)/Alhydrogel was well-tolerated; the most frequent adverse events were mild or moderate injection site tenderness and pain, and mild or moderate nausea and headache. No serious adverse events or adverse events of special interest related to vaccination were observed. Significantly higher levels of antigen-specific IgG antibodies were induced in those who received 100 µg Na-APR-1(M74) than those who received 30 µg of antigen. Adding GLA-AF to Na-APR-1(M74)/Alhydrogel resulted in higher levels of IgG against Na-APR-1(M74) in both the 30 and 100 µg Na-APR-1(M74) groups in comparison to the non-GLA formulations at the same antigen dose. CONCLUSIONS: Vaccination of hookworm-naïve adults with recombinant Na-APR-1(M74) was well-tolerated, safe, and induced significant IgG responses against the vaccine antigen Na-APR-1(M74). Given these favorable results, clinical trials of this product were initiated in hookworm-endemic areas of Gabon and Brazil.


Assuntos
Infecções por Uncinaria , Vacinas , Adjuvantes Imunológicos , Adulto , Hidróxido de Alumínio , Ancylostomatoidea , Animais , Anticorpos Neutralizantes , Infecções por Uncinaria/prevenção & controle , Humanos , Imunogenicidade da Vacina , Imunoglobulina G , Lipídeo A , Peptídeo Hidrolases , Tabaco/genética
15.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 34(4): 438-444, 2022 Aug 19.
Artigo em Chinês | MEDLINE | ID: mdl-36116939

RESUMO

As a type of highly plastic innate immune cells, macrophages may be differentiated into M1 and M2 macrophages upon different stimuli, and M2 macrophages are involved in immune regulation, tissue remodeling and regeneration, and wound healing. Previous epidemiological studies have shown a significant negative correlation between the prevalence of helminth infections and the incidence of inflammatory diseases, such as allergy and autoimmune diseases. As a common type of intestinal helminths, hookworm infection may trigger high levels of type II host immune responses, with alternative activation of macrophages, which are effective to inhibit the development and progression of inflammatory diseases. This review summarizes the advances in alternative activation of macrophages in hookworm therapy for inflammatory diseases.


Assuntos
Helmintíase , Infecções por Uncinaria , Ancylostomatoidea , Animais , Diferenciação Celular , Macrófagos
16.
Exp Parasitol ; 242: 108393, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36179854

RESUMO

For some nematodes, alterations that leads to a resistance genotype may be accompanied by other modifications, causing changes in the biology of the parasite, although the exact mechanisms of this relationship are still not very clear. These alterations can have deleterious effects on their survival or even potentiate their pathogenicity. In this study a phenotypic characterization was carried out to compare two Ancylostoma ceylanicum isolates, a wild type one, kept in the laboratory and an albendazole selected resistant isolate (AceyBZR2). Differences in some analyzed parameters, between the two strains, were registered, as patency period, number and size of the recovered worms, including differences in the body structures. The AceyBZR2 isolate showed to be less adapted to the host, leading to a smaller number of recovered worms. However, no difference on the female egg content was observed between the two isolates. Concerning blood evaluation, no differences were found between the wild type and AceyBZR2 isolates, related to hemoglobin and hematocrit levels. However, animals in the group infected with the wild type isolate had lower serum iron concentrations than animals in the AceyBZR2 group. The possibility that the AceyBZR2 isolate might be resistant to other drugs was evaluated and it was demonstrated that it does not present cross-resistance to ivermectin and nitazoxanide. However, when animals infected with the AceyBZR2 were treated with another drug from the benzimidazoles group (mebendazole), the cross-resistance effect was observed. Morphometric analyses were performed comparing female and male adult worms from the two isolates. The results presented here allow a better understanding of the parasite-host relationship and may constitute a useful basis for establishing future control strategies for soil-transmitted helminths.


Assuntos
Albendazol , Anti-Helmínticos , Animais , Masculino , Feminino , Albendazol/farmacologia , Albendazol/uso terapêutico , Ancylostomatoidea , Mebendazol , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Solo , Ferro
17.
PLoS One ; 17(9): e0275013, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36155987

RESUMO

Metabolomics provides a powerful tool to study physiological changes in response to various perturbations such as vaccination. We explored whether metabolomic changes could be seen after vaccination in a phase I trial where Gabonese adults living either in rural or semi-urban areas received the subunit hookworm vaccine candidates (Na-GST-1 and Na-APR-1 (M74) adjuvanted with Alhydrogel plus GLA-AF (n = 24) or the hepatitis B vaccine (n = 8) as control. Urine samples were collected and assayed using targeted 1H NMR spectroscopy. At baseline, a set of metabolites significantly distinguished rural from semi-urban individuals. The pre- and post-vaccination comparisons indicated significant changes in few metabolites but only one day after the first vaccination. There was no relationship with immunogenicity. In conclusion, in a small phase 1 trial, urinary metabolomics could distinguish volunteers with different environmental exposures and reflected the safety of the vaccines but did not show a relationship to immunogenicity.


Assuntos
Ancylostomatoidea , Infecções por Uncinaria , Adjuvantes Imunológicos , Adulto , Hidróxido de Alumínio , Animais , Gabão , Vacinas contra Hepatite B , Humanos , Imunogenicidade da Vacina
18.
Sci Rep ; 12(1): 13935, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35978014

RESUMO

Preventive chemotherapy (PC) that remains the main control strategy recommended by the World Health Organization to achieve the elimination of soil-transmitted helminth (STH) infections as a public health problem must be strengthened by identifying the remaining transmission hot-spots for the deployment of appropriate control measures. This study was designed to assess the prevalence and infections intensities of soil-transmitted helminths and perform micro scale mapping in order to identify transmission hot-spots for targeted control operations. Stool samples were collected from 1775 children in ten primary schools of eight sub-districts of Makenene in Cameroon. Kato Katz technique was used to process and examine stool samples to detect the eggs of soil-transmitted nematodes. The prevalence of soil-transmitted helminth species as well as the infection intensities was compared. Data visualizations in forms of maps were made using Quantum geographic information system (QGIS) software. The overall prevalence of soil-transmitted helminth infections was 4.8% with a 95% confidence interval (CI) of 3.8-5.9%: 3.0% (95% CI 2.2-3.9) for Ascaris lumbricoides, 1.4% (95% CI 0.9-2.0) for Trichuris trichiura and 0.8% (95% CI 0.5-1.4) for hookworms. The prevalence of soil-transmitted helminth species differ significantly between schools and sub-districts. The intensity of infections was light (2.4%, 1.1% and 0.8%), moderate (0.4%, 0.1% and 0.1%) and heavy (0.2%, 0.2% and 0%) for A. lumbricoides, T. trichiura and hookworm respectively. The mean intensity of infections was 7255 EPG for A. lumbricoides, 2900 EPG for T. trichiura and 298 EPG for hookworm. Between schools, significant difference was recorded in the means of infection intensities of T. Trichiura and hookworms but not for A. lumbricoides. This difference was also significant for T. Trichiura when comparison were between sex. No significant difference were recorded when the comparison were between age. Fine mapping revealed that children harbouring heavy infections were clustered in the same sub-districts; highlighting the presence of high endemicity sub-districts and hot-spots for the transmission of different soil-transmitted helminth species. This study showed a diversity in the prevalence and transmission of different soil-transmitted helminth species. It also hightlighted the need for micro scale mapping to enable the localisation of high endemicity sub-districts and transmission hot-spot sites where targeted control operations must be deployed to achieve STH elimination.


Assuntos
Helmintíase , Helmintos , Infecções por Uncinaria , Ancylostomatoidea , Animais , Ascaris lumbricoides , Criança , Fezes/parasitologia , Helmintíase/tratamento farmacológico , Infecções por Uncinaria/epidemiologia , Humanos , Prevalência , Solo/parasitologia , Trichuris
19.
PLoS Negl Trop Dis ; 16(8): e0010593, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35917364

RESUMO

BACKGROUND: Periodic administration of anthelmintic drugs is a cost-effective intervention for morbidity control of soil-transmitted helminth (STH) infections. However, with programs expanding, drug pressure potentially selecting for drug-resistant parasites increases. While monitoring anthelmintic drug efficacy is crucial to inform country control program strategies, different factors must be taken into consideration that influence drug efficacy and make it difficult to standardize treatment outcome measures. We aimed to identify suitable approaches to assess and compare the efficacy of different anthelmintic treatments. METHODOLOGY: We built an individual participant-level database from 11 randomized controlled trials and two observational studies in which subjects received single-agent or combination therapy, or placebo. Eggs per gram of stool were calculated from egg counts at baseline and post-treatment. Egg reduction rates (ERR; based on mean group egg counts) and individual-patient ERR (iERR) were utilized to express drug efficacy and analyzed after log-transformation with a linear mixed effect model. The analyses were separated by follow-up duration (14-21 and 22-45 days) after drug administration. PRINCIPAL FINDINGS: The 13 studies enrolled 5,759 STH stool-positive individuals; 5,688 received active medication or placebo contributing a total of 11,103 STH infections (65% had two or three concurrent infections), of whom 3,904 (8,503 infections) and 1,784 (2,550 infections) had efficacy assessed at 14-21 days and 22-45 days post-treatment, respectively. Neither the number of helminth co-infections nor duration of follow-up affected ERR for any helminth species. The number of participants treated with single-dose albendazole was 689 (18%), with single-dose mebendazole 658 (17%), and with albendazole-based co-administrations 775 (23%). The overall mean ERR assessed by day 14-21 for albendazole and mebendazole was 94.5% and 87.4%, respectively on Ascaris lumbricoides, 86.8% and 40.8% on hookworm, and 44.9% and 23.8% on Trichuris trichiura. The World Health Organization (WHO) recommended criteria for efficacy were met in 50%, 62%, and 33% studies of albendazole for A. lumbricoides, T. trichiura, and hookworm, respectively and 25% of mebendazole studies. iERR analyses showed similar results, with cure achieved in 92% of A. lumbricoides-infected subjects treated with albendazole and 93% with mebendazole; corresponding figures for hookworm were 70% and 17%, and for T. trichiura 22% and 20%. CONCLUSIONS/SIGNIFICANCE: Combining the traditional efficacy assessment using group averages with individual responses provides a more complete picture of how anthelmintic treatments perform. Most treatments analyzed fail to meet the WHO minimal criteria for efficacy based on group means. Drug combinations (i.e., albendazole-ivermectin and albendazole-oxantel pamoate) are promising treatments for STH infections.


Assuntos
Anti-Helmínticos , Helmintíase , Helmintos , Infecções por Uncinaria , Tricuríase , Albendazol/uso terapêutico , Ancylostomatoidea , Animais , Anti-Helmínticos/uso terapêutico , Helmintíase/tratamento farmacológico , Infecções por Uncinaria/tratamento farmacológico , Humanos , Mebendazol/uso terapêutico , Solo/parasitologia , Tricuríase/tratamento farmacológico , Trichuris
20.
Emerg Infect Dis ; 28(9): 1870-1872, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35997602

RESUMO

Ancylostoma ceylanicum hookworms are recognized agents of human infection in the Asia-Pacific region. We investigated prevalence of zoonotic hookworm infections in dogs in Grenada in 2021; 40.8% were infected by hookworms, including Ancylostoma ceylanicum. Surveillance of this parasite in dogs and humans is needed in tropical/subtropical countries in the Americas.


Assuntos
Ancylostoma , Ancilostomíase , Ancylostomatoidea , Ancilostomíase/epidemiologia , Ancilostomíase/parasitologia , Ancilostomíase/veterinária , Animais , Cães , Fezes/parasitologia , Granada/epidemiologia , Humanos , Zoonoses/epidemiologia
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