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1.
BMC Infect Dis ; 20(1): 803, 2020 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-33121458

RESUMEN

BACKGROUND: Soil-transmitted helminths are more prevalent in tropics and sub-tropics including Ethiopia. Despite their high prevalence, direct saline microscopy with its low sensitivity has been used as a diagnostic method in almost all health facilities in Ethiopia. Alternative diagnostic methods which have higher sensitivity are not yet implemented. Therefore, this study aimed to compare and evaluate the performance of diagnostic methods for soil transmitted helminths. METHODS: A cross-sectional study among 520 school children was conducted from October to December, 2019 in Amhara National Regional State. The study participants were selected using systematic random sampling technique. Stool samples were processed via formol ether concentration, Kato-Katz, spontaneous tube sedimentation and agar plate culture techniques. Data was entered into Epi-data version 3.1 and analysis was done using SPSS version 20.0. The sensitivity, specificity, and negative predictive value were calculated against the combined result. Strength of agreement of the diagnostic methods was determined by Kappa value. RESULTS: The Overall prevalence of soil transmitted helminths was 40.8% using combination of methods. The prevalence 24.4, 22.5, and 32.4%, respectively was recorded by using formol ether concentration, Kato-Katz and spontaneous tube sedimentation. The highest prevalence of hookworm (29.2%) was detected by the agar plate culture. The sensitivity and negative predictive value of formol ether concentration were 57.9 and 78.4%, for Kato-Katz thick smear 55.2 and 76.4%, for spontaneous tube sedimentation were 79.2 and 87.5% to soil transmitted helminths detection, respectively. The sensitivity and negative predictive value of agar plate culture to hookworm detection were 86.4 and 93.5%, respectively. CONCLUSION: Spontaneous tube sedimentation shows higher sensitivity in the detection of soil transmitted helminth infections. Agar plate culture method also indicated better performance for hookworm detection than other methods. Therefore, the employment of spontaneous tube sedimentation technique for routine laboratory and agar plate culture for research purposes will significantly aid in accurate diagnosis of parasitic infections.


Asunto(s)
Ancylostomatoidea/aislamiento & purificación , Pruebas Diagnósticas de Rutina/métodos , Infecciones por Uncinaria/diagnóstico , Infecciones por Uncinaria/transmisión , Suelo/parasitología , Adolescente , Animales , Niño , Estudios Transversales , Etiopía/epidemiología , Heces/parasitología , Femenino , Formaldehído , Infecciones por Uncinaria/epidemiología , Infecciones por Uncinaria/parasitología , Humanos , Masculino , Microscopía/métodos , Prevalencia , Sensibilidad y Especificidad
2.
PLoS One ; 15(9): e0239680, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32986746

RESUMEN

Geohelminthiasis is a worldwide problem, especially in low-income countries. Children from rural areas and those living in poverty, lacking basic health amenities and having poor environmental sanitation are likely to be affected. Adverse effects such as anemia, protein malnutrition, colitis are common which can affect both the children's physical and mental growing development. A cross-sectional study on geohelminthiasis was conducted among children from 238 households in 13 villages in Kota Marudu of northern Sabah, East Malaysia. The study involved interviewing villagers using questionnaires to collect demographic and socio-economic data, getting faecal samples from the children, collecting soil samples and identifying parasite eggs with microscopy and molecular methods. A total of 407 children (6 months-17 years old) enrolled in the study. Geohelminthiasis was detected in the faecal samples of children from 54% (7/13) of the villages with mean prevalence of infection per village of 9.0% (0%-34.9%). On a household basis, 18% (43/238) of the households sampled had infected children, with mean prevalence rate per household of 11% (0%-43%). The prevalence was for Ascaris lumbricoides: 9.6% (39/407), Trichuris trichiura: 2.7% (11/407) and hookworms (Necator americanus and Ancylostoma sp.): 2.7% (11/407). The overall mean infection rate of the children examined was 14.3%. Significantly higher prevalence was recorded for the children of mothers who did not have any formal education (p = 0.003); household income of less than USD119 (RM500) (p<0.001); children from homes without proper sanitation facilities (p<0.001); children who usually go about barefoot (p<0.001) and not washing feet before entering the house (p = 0.017). Soil samples were found to have geohelminth eggs or larvae which could be due to unhygienic sanitation practices. This study shows the geohelminthiasis is prevalent in the villages, and the risk factors are lack of maternal education, low income, poor sanitation facilities and irregular deworming practice. Expanding deworming coverage in the study region may help reduce the worm infections in these communities, so that the mental and physical development of the children would not be affected by geohelminthiasis. The data on the prevalence of geohelminthiasis in this study would contribute to better public health monitoring and operation to reduce the infection in rural areas.


Asunto(s)
Ancylostomatoidea/aislamiento & purificación , Ascariasis/epidemiología , Ascaris lumbricoides/aislamiento & purificación , Infecciones por Uncinaria/epidemiología , Tricuriasis/epidemiología , Trichuris/aislamiento & purificación , Adolescente , Animales , Ascariasis/parasitología , Niño , Preescolar , Estudios Transversales , Heces/parasitología , Femenino , Infecciones por Uncinaria/parasitología , Humanos , Lactante , Malasia/epidemiología , Masculino , Pobreza , Prevalencia , Salud Pública , Factores de Riesgo , Población Rural , Saneamiento , Tricuriasis/parasitología
3.
Am J Trop Med Hyg ; 103(5): 1958-1968, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32840198

RESUMEN

Hookworm is an intestinal parasite that infects nearly 230 million people, with another 5.1 billion at risk, especially in poverty-stricken tropical and subtropical regions. Pregnancy is an especially vulnerable time for hookworm infection because of its effect on both maternal and subsequently fetal health. A systematic review and meta-analysis was conducted. The meta-analysis was performed on the association between maternal hookworm and maternal anemia, as well as maternal hookworm coinfection with malaria. The prevalence of hookworm ranged from 1% to 78% in pregnant women, whereas malaria prevalence ranged from 11% to 81%. Pregnant women with hookworm infection were more likely to have anemia (combined odds ratio [cOR] 2.55 [2.20, 2.96], P < 0.001). In addition, pregnant woman with hookworm were more likely to have malaria coinfection (cOR 1.60 [1.38, 1.86], P < 0.001). Other effects on maternal and child health were investigated and summarized without systematic review or meta-analysis because of the limited study numbers. Despite current deworming recommendations in pregnant women, heavy hookworm burden, coinfection with malaria, and subsequent anemia persist. Although this is likely due, in part, to a lack of implementation of preventive chemotherapy, additional interventions such as health education, proper waste management, or linking malaria and soil-transmitted helminth treatment and prevention programs may also be needed. Further investigations on maternal-child outcomes as a result of hookworm infection during pregnancy will highlight public health interventional targets to reduce morbidity in pregnant women and children globally.


Asunto(s)
Anemia/epidemiología , Coinfección , Infecciones por Uncinaria/epidemiología , Malaria/epidemiología , Salud Materna , Complicaciones Parasitarias del Embarazo/epidemiología , Ancylostomatoidea , Anemia/complicaciones , Anemia/parasitología , Animales , Estudios de Cohortes , Estudios Transversales , Femenino , Educación en Salud , Infecciones por Uncinaria/complicaciones , Infecciones por Uncinaria/parasitología , Humanos , Malaria/complicaciones , Malaria/parasitología , Embarazo , Complicaciones Parasitarias del Embarazo/parasitología , Salud Pública
4.
J Parasitol ; 106(3): 383-391, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32491171

RESUMEN

The long-term fidelity of pinniped hosts to their natal rookery site suggests the genetic architecture of their Uncinaria spp. hookworms should be strongly structured by host breeding biology. However, historical events affecting host populations may also shape parasite genetic structure. Sequences of the mitochondrial cytochrome c oxidase 1 (COI) gene of 86 Uncinaria lucasi individuals were obtained to assess genetic variation and structure of nematodes from 2 host species (68 hookworms from northern fur seals; 18 hookworms from Steller sea lions) and rookeries from 3 widely separated geographic regions: the western Bering Sea and Sea of Okhotsk, eastern Bering Sea, and the eastern Pacific Ocean. High COI haplotype (h = 0.96-0.98) and nucleotide (π = 0.014) diversity was found. The haplotype network showed a star-shaped pattern with a large number of haplotypes separated by few substitutions. The network did not show separation of U. lucasi by geographic region or host species. Fst values between U. lucasi individuals representing geographic regions showed no differentiation, consistent with the absence of genetic structure. At face value, this lack of genetic structure in U. lucasi suggests high gene flow but could also be explained by recent (post-glacial) population expansions of northern fur seals and their hookworms.


Asunto(s)
Ancylostomatoidea/fisiología , Caniformia/parasitología , Infecciones por Uncinaria/veterinaria , Secuencia de Aminoácidos , Ancylostomatoidea/genética , Animales , Secuencia de Bases , Complejo IV de Transporte de Electrones/genética , Femenino , Variación Genética , Haplotipos/genética , Infecciones por Uncinaria/parasitología , Infecciones por Uncinaria/transmisión , Masculino , Mitocondrias/enzimología , Océano Pacífico , Alineación de Secuencia/veterinaria
5.
PLoS Negl Trop Dis ; 14(6): e0008315, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32497042

RESUMEN

BACKGROUND: Soil transmitted helminths are highly prevalent worldwide. Globally, approximately 1.5 billion people are infected with Ascaris lumbricoides, Trichuris trichiura or hookworm. Endemic countries carry out periodic mass treatment of at-risk populations with albendazole or mebendazole as a control measure. Most prevalence studies have focused on school aged children and therefore control programs are implemented at school level, not at community level. In this study, the prevalence of intestinal helminths, including Strongyloides stercoralis, was examined using a comprehensive laboratory approach in a community in north-western Ethiopia. METHODS: A cross-sectional survey was conducted on 792 individuals ≥5 years old in randomly selected houses in a rural district. Stools were examined using three techniques: a formol-ether concentration, the Baermann technique and a real time polymerase chain reaction test (these last two specific for S. stercoralis). Statistical analyses were performed between two large age groups, children (≤14 years old) and adults (≥15 years old). RESULTS: The prevalence of helminths was 91.3%; (95% CI: 89.3-93.3%). Hookworm was the most prevalent, 78.7% (95% CI 75.6-81.4%), followed by S. stercoralis 55.7% (95% CI 52.2-59.1%). Co-infection with both was detected in 45.4% (95% CI 42.0-49.0%) of the participants. The mean age of hookworm-infected individuals was significantly higher than non-infected ones (p = 0.003). Also, S. stercoralis infection was significantly associated with age, being more prevalent in adults (p = 0.002). CONCLUSIONS: This is the highest prevalence of S. stercoralis detected in Ethiopia so far. Our results highlight the need of searching specifically for infection by this parasite since it usually goes unnoticed if helminth studies rely only on conventional diagnostic techniques, i.e. Kato-Katz. Moreover, the focus of these programs on children undermines the actual prevalence of hookworm. The adult population acts as a reservoir for both hookworm and S. stercoralis and this fact may negatively impact the current control programs in Ethiopia which only target treatment of school aged children. This reservoir, together with a lack of adequate water, sanitation and hygiene, increases the probability of re-infection in children. Finally, the high prevalence of S. stercoralis found calls for a comprehensive diagnostic approach in endemic areas in addition to a revision of control measures that is, adding ivermectin to current albendazole/mebendazole, since it is the drug of choice for S. stercoralis.


Asunto(s)
Helmintiasis/epidemiología , Infecciones por Uncinaria/epidemiología , Parasitosis Intestinales/epidemiología , Esquistosomiasis mansoni/epidemiología , Estrongiloidiasis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Antihelmínticos , Niño , Preescolar , Estudios Transversales , Etiopía/epidemiología , Heces/parasitología , Femenino , Helmintiasis/parasitología , Infecciones por Uncinaria/parasitología , Humanos , Parasitosis Intestinales/parasitología , Masculino , Persona de Mediana Edad , Prevalencia , Población Rural , Esquistosomiasis mansoni/parasitología , Estrongiloidiasis/parasitología , Adulto Joven
6.
BMC Infect Dis ; 20(1): 376, 2020 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-32460712

RESUMEN

BACKGROUND: Despite the existence of a population-based control program using single dose albendazole or mebendazole as a preventive chemotherapy, hookworm transmission remains high. It causes a negative impact on the growth and school performance of children. In connection to this preventive chemotherapy, different studies produced conflicting results. This study aimed at evaluating the efficacy of single (500 mg) versus multiple doses (100 mg twice a day during three consecutive days) of mebendazole against hookworm infections among school-aged children. METHODS: This randomized open-label clinical trial took place among school-aged children (6-14 years old) in Burie and Debre Elias towns, Northwest Ethiopia. Using simple randomization, eligible hookworm-positive children were allocated (1:1) to either a single or multiple dose treatment arms. Stool samples were collected and processed using McMaster method at baseline and follow-up period (14-21 days after treatment). Only laboratory technicians were blinded. The cure and egg reduction rates were the primary and secondary therapeutic outcome measures against hookworm infections, respectively. An independent t-test was used to compare group means, and logistic regression was used to calculate odds ratio (OR). P-value < 0.05 at 95% CI was considered statistically significant. RESULT: One hundred eight children, 54 in each treatment arm had completed baseline data and received allocated treatment. One hundred three children had completed follow-up data records and included for the final efficacy analysis. Cure rate against hookworm was significantly higher in the multiple dose (96.1%) than in the single dose (30.8%) with OR = 55.125; 95% CI: 11.92-254.9; P < 0.001. The egg reduction rate in the multiple dose treatment arm (99.5%) was also significantly higher than in the single dose arm (68.9%) with difference t (101) =5.38; 95% CI 230.95-505.36; P < 0.001. CONCLUSION: The single dose regimen of mebendazole for the treatment of hookworm infections showed poor cure and egg reduction rates, while the multiple doses revealed satisfactory. Although multiple dose regimen administration is a bit more complex than the single dose, we strongly encourage replacing it with multiple dose regimen during deworming programs in hookworm endemic areas. TRIAL REGISTRATION: This trial is retrospectively registered in www.pactr.org, number PACTR201911466695052 on November 26, 2019.


Asunto(s)
Antihelmínticos/administración & dosificación , Infecciones por Uncinaria/prevención & control , Mebendazol/administración & dosificación , Adolescente , Albendazol/administración & dosificación , Ancylostomatoidea/efectos de los fármacos , Ancylostomatoidea/fisiología , Animales , Niño , Preescolar , Protocolos Clínicos , Esquema de Medicación , Etiopía , Femenino , Infecciones por Uncinaria/parasitología , Humanos , Modelos Logísticos , Masculino , Estudiantes/estadística & datos numéricos
7.
Parasit Vectors ; 13(1): 99, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32113471

RESUMEN

BACKGROUND: Ancylostomatids ('hookworms') are among the most important zoonotic nematode parasites infecting dogs worldwide. Ancylostoma caninum and Uncinaria stenocephala are two of the most common hookworm species that infect dogs. Both immature and adult stages of hookworms are voracious blood feeders and can cause death in young dogs before infection can be detected by routine fecal examination. Hence, treatment of both immature and adult stages of hookworms will decrease the risk of important clinical disease in the dog as well as the environmental contamination caused by egg-laying adults, which should reduce the risk of infection for both dogs and humans. The studies presented here were conducted to evaluate the efficacy of a novel, oral chewable tablet containing sarolaner, moxidectin and pyrantel (Simparica Trio™), against induced larval (L4), immature adult (L5) and adult A. caninum, and adult U. stenocephala infections in dogs. METHODS: Eight negative-controlled, masked, randomized laboratory studies were conducted. Two separate studies were conducted against each of the target parasites and stages. Sixteen or 18 purpose bred dogs, 8 or 9 in each of the two treatment groups, were included in each study. Dogs experimentally infected with the target parasite were dosed once on Day 0 with either placebo tablets or Simparica Trio™ tablets to provide minimum dosages of 1.2 mg/kg sarolaner, 24 µg/kg moxidectin and 5.0 mg/kg pyrantel (as pamoate salt). Timing of dosing relative to parasite inoculation allowed for efficacy to be evaluated primarily against the target parasite stage. Worm counts were conducted 7 or 8 days after treatments during necropsy. Efficacy was based on the number of worms recovered at necropsy compared to placebo control. RESULTS: Based on geometric mean worm counts, efficacy of Simparica Trio™ was ≥ 98.4% against L4 larval stage of A. caninum, ≥ 99.8% against immature adult (L5) A. caninum, and 100% against adult A. caninum and adult U. stenocephala. CONCLUSIONS: These studies confirm the efficacy of a single oral dose of a novel, chewable tablet containing sarolaner, moxidectin and pyrantel (Simparica Trio™) against L4 larval and immature adult (L5) A. caninum, and adult A. caninum and U. stenocephala infections in dogs.


Asunto(s)
Antinematodos/administración & dosificación , Enfermedades de los Perros/tratamiento farmacológico , Infecciones por Uncinaria/veterinaria , Administración Oral , Ancylostomatoidea/crecimiento & desarrollo , Animales , Azetidinas/administración & dosificación , Enfermedades de los Perros/parasitología , Perros , Combinación de Medicamentos , Infecciones por Uncinaria/tratamiento farmacológico , Infecciones por Uncinaria/parasitología , Estadios del Ciclo de Vida/efectos de los fármacos , Macrólidos/administración & dosificación , Carga de Parásitos , Pirantel/administración & dosificación , Compuestos de Espiro/administración & dosificación , Comprimidos , Resultado del Tratamiento
8.
Parasit Vectors ; 13(1): 136, 2020 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-32171305

RESUMEN

Hookworm infection is a major public health problem that threatens about 500 million people throughout tropical areas of the world. Adult hookworms survive for many years in the host intestine, where they suck blood, causing iron deficiency anemia and malnutrition. Numerous molecules, named excretory/secretory (ES) products, are secreted by hookworm adults and/or larvae to aid in parasite survival and pathobiology. Although the molecular cloning and characterization of hookworm ES products began 25 years ago, the biological role and molecular nature of many of them are still unclear. Hookworm ES products, with distinct structures and functions, have been linked to many essential events in the disease pathogenesis. These events include host invasion and tissue migration, parasite nourishment and reproduction, and immune modulation. Several of these products represent promising vaccine targets for controlling hookworm disease and therapeutic targets for many inflammatory diseases. This review aims to summarize our present knowledge about hookworm ES products, including their role in parasite biology, host-parasite interactions, and as vaccine and pharmaceutical targets and to identify research gaps and future research directions in this field.


Asunto(s)
Ancylostomatoidea/inmunología , Líquidos Corporales/inmunología , Infecciones por Uncinaria/inmunología , Infecciones por Uncinaria/parasitología , Interacciones Huésped-Parásitos/inmunología , Ancylostoma , Ancylostomatoidea/metabolismo , Animales , Antioxidantes , Líquidos Corporales/química , Clonación Molecular , Femenino , Proteínas del Helminto/inmunología , Infecciones por Uncinaria/prevención & control , Infecciones por Uncinaria/terapia , Humanos , Factores Inmunológicos , Masculino , Péptido Hidrolasas , Inhibidores de Proteasas , Vacunas/inmunología
9.
Parasitol Int ; 75: 102051, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31911156

RESUMEN

Helminth diseases are the ancient scourges of humans and their damages are 'silent and insidious'. Of the helminth infections, schistosomiasis and hookworm infection have a great impact. This review covers information regarding vaccine candidates against schistosomiasis and hookworms that reached at least up to the phase-1 trial and literatures regarding other vaccine candidates have been excluded. For clinical manifestations, all available literatures were included, and for epidemiology and global burden of the diseases (GBD), literatures only within 2000-2019 were included. Literatures were searched surfing various databases including PubMED, Google Scholar, and Science Direct and overall over 150 literatures were identified. Globally ~250 million people are suffering from schistosomiasis, resulting 1430 thousand DALY (disability adjusted life year) per year. On the other hand, about 1.3 billion people are infected with hookworm (HW), and according to WHO, ~878 million school-age children (SAC) are at risk. HW is estimated to cause 65,000 deaths annually, accounts for 845 thousand DALYs as well as to cause 6-35.3% loss in productivity. Despite tremendous efforts, very few anthelmintic vaccine candidates such as Na-GST-1, Na-APR-1 and Na-ASP-2 against HW, and Sm28GST/Sh28GST, Sm-p80, Sm14 and Sm-TSP-1/SmTSP-2 against schistosomiasis reached up to the clinical trials. More efforts are needed to achieve the WHO targets taken against the maladies.


Asunto(s)
Costo de Enfermedad , Infecciones por Uncinaria , Esquistosomiasis , Vacunas/uso terapéutico , Infecciones por Uncinaria/parasitología , Infecciones por Uncinaria/prevención & control , Humanos , Esquistosomiasis/parasitología , Esquistosomiasis/prevención & control , Vacunas/análisis
10.
J Infect Dis ; 221(6): 934-942, 2020 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-31621864

RESUMEN

BACKGROUND: The human hookworm, Necator americanus, is a parasite that infects almost half a billion people worldwide. Although treatment is available, vaccination is favorable to combat the spread of this parasite due to its wide distribution and continuous reinfection cycle in endemic communities. METHODS: We have designed a lipopeptide oral delivery system using a B-cell epitope derived from the aspartic protease Na-APR-1 from N americanus, attached to a T-helper epitope. Lipopeptides were self-assembled into nanoparticles or entrapped in liposomes that were electrostatically coated with alginate and trimethyl chitosan polymer shields. The adjuvant-free vaccine candidates were orally administered to mice and generated a humoral immune response against both peptide antigen, and the parent protein in the hookworm gut. RESULTS: The vaccine candidates were evaluated in a rodent hookworm challenge model, resulting in up to 98% and 99% decreases in mean intestinal worm and egg burdens in immunized mice, respectively. CONCLUSIONS: Lipopeptide survived the gastrointestinal conditions, induced humoral immune responses and drived protection against parasite challenge infection.


Asunto(s)
Infecciones por Uncinaria/prevención & control , Lipopéptidos/inmunología , Vacunas/inmunología , Animales , Infecciones por Uncinaria/parasitología , Inmunidad Humoral , Lipopéptidos/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Necator americanus/metabolismo , Vacunación
11.
Korean J Parasitol ; 58(6): 619-625, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33412765

RESUMEN

Human hookworm infections caused by adult Ancylostoma spp. and Necator americanus are one of the most important tropical diseases. We performed a survey of intestinal helminths using the Kato-Katz fecal examination technique targeting 1,156 villagers residing in 2 northern provinces (Preah Vihear and Stung Treng) of Cambodia in 2018. The results revealed a high overall egg positive rate of intestinal helminths (61.9%), and the egg positive rate of hookworms was 11.6%. Nine of the hookworm egg positive cases in Preah Vihear Province were treated with 5-10 mg/kg pyrantel pamoate followed by purging with magnesium salts, and a total of 65 adult hookworms were expelled in diarrheic stools. The adult hookworms were analyzed morphologically and molecularly to confirm the species. The morphologies of the buccal cavity and dorsal rays on the costa were observed with a light microscope, and the nucleotide sequences of mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were analyzed. The majority of the hookworm adults (90.7%) were N. americanus, whereas the remaining 9.3% were Ancylostoma ceylanicum, a rare hookworm species infecting humans. The results revealed a high prevalence of hookworm infections among people in a northern part of Cambodia, suggesting the necessity of a sustained survey combined with control measures against hookworm infections.


Asunto(s)
Ancylostoma/aislamiento & purificación , Infecciones por Uncinaria/diagnóstico , Infecciones por Uncinaria/parasitología , Parasitosis Intestinales/diagnóstico , Parasitosis Intestinales/parasitología , Necator americanus/aislamiento & purificación , Patología Molecular/métodos , Población Rural , Adulto , Ancylostoma/genética , Ancylostoma/ultraestructura , Animales , Cambodia/epidemiología , Complejo IV de Transporte de Electrones , Heces/parasitología , Femenino , Infecciones por Uncinaria/epidemiología , Infecciones por Uncinaria/prevención & control , Humanos , Parasitosis Intestinales/epidemiología , Masculino , Microscopía , Necator americanus/genética , Necator americanus/ultraestructura , Prevalencia , Adulto Joven
12.
PLoS One ; 14(10): e0221190, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31589618

RESUMEN

BACKGROUND: Intestinal parasitic infection affects 3.5 billion people in the world and mostly affecting the low socio-economic groups. The objectives of this research works were to estimate the prevalence and determinants of intestinal parasitic infection among family members of known intestinal parasite infected patients. METHODS AND MATERIALS: A comparative cross-sectional study design was implemented in the urban and rural settings of Mecha district. The data were collected from August 2017toMarch 2019 from intestinal parasite infected patient household members. Epi-info software was used to calculate the sample size, 4531 household members were estimated to be included. Data were collected using interview technique, and collecting stool samples from each household contact of intestinal parasite patients. Descriptive statistics were used to estimate the prevalence of intestinal parasites among known contacts of intestinal parasite patients/family members. Binary logistic regression was used to identify the determinant factors of intestinal parasitic infection among family members. RESULTS: The prevalence of intestinal parasite among household contacts of intestinal parasite-infected family members was 86.14% [95% CI: 86.14% - 87.15%]. Hookworm infection was the predominant type of infection (18.8%). Intestinal parasitic infection was associated with sex, environmental sanitation, overcrowding, personal hygiene, residence, substandard house, role in the household, source of light for the house, trimmed fingernails, family size, regular handwashing practice. Protozoa infection was associated with habit of ingesting raw vegetable, playing with domestic animals, water source and the presence of household water filtering materials. CONCLUSION: High prevalence of intestinal parasitic infection was observed among household contacts of primary cases.


Asunto(s)
Infecciones por Uncinaria , Parasitosis Intestinales , Infecciones por Protozoos , Población Rural , Adolescente , Adulto , Niño , Preescolar , Estudios Transversales , Etiopía/epidemiología , Composición Familiar , Femenino , Infecciones por Uncinaria/epidemiología , Infecciones por Uncinaria/parasitología , Humanos , Lactante , Recién Nacido , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Masculino , Persona de Mediana Edad , Prevalencia , Infecciones por Protozoos/epidemiología , Infecciones por Protozoos/parasitología , Saneamiento
13.
Infect Dis Poverty ; 8(1): 82, 2019 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-31575378

RESUMEN

BACKGROUND: The goal of soil-transmitted helminthiases (STH) control programmes is to eliminate STH-associated morbidity in the target population by reducing the prevalence of moderate- and heavy-intensity infections and the overall STH infection prevalence mainly through preventive chemotherapy (PC) with either albendazole or mebendazole. Endemic countries should measure the success of their control programmes through regular epidemiological assessments. We evaluated changes in STH prevalence in countries that conducted effective PC coverage for STH to guide changes in the frequency of PC rounds and the number of tablets needed. METHODS: We selected countries from World Health Organization (WHO)'s Preventive Chemotherapy and Transmission control (PCT) databank that conducted ≥5 years of PC with effective coverage for school-age children (SAC) and extracted STH baseline and impact assessment data using the WHO Epidemiological Data Reporting Form, Ministry of Health reports and/or peer-reviewed publications. We used pooled and weighted means to plot the prevalence of infection with any STH and with each STH species at baseline and after ≥5 years of PC with effective coverage. Finally, using the WHO STH decision tree, we estimated the reduction in the number of tablets needed. RESULTS: Fifteen countries in four WHO regions conducted annual or semi-annual rounds of PC for STH for 5 years or more and collected data before and after interventions. At baseline, the pooled prevalence was 48.9% (33.1-64.7%) for any STH, 23.2% (13.7-32.7%) for Ascaris lumbricoides, 21.01% (9.7-32.3%) for Trichuris trichiura and 18.2% (10.9-25.5%) for hookworm infections, while after ≥5 years of PC for STH, the prevalence was 14.3% (7.3-21.3%) for any STH, 6.9% (1.3-12.5%) for A. lumbricoides, 5.3% (1.06-9.6%) for T. trichiura and 8.1% (4.0-12.2%) for hookworm infections. CONCLUSIONS: Countries endemic for STH have made tremendous progress in reducing STH-associated morbidity, but very few countries have data to demonstrate that progress. In this study, the data show that nine countries should adapt their PC strategies and the frequency of PC rounds to yield a 36% reduction in drug needs. The study also highlights the importance of impact assessment surveys to adapt control strategies according to STH prevalence.


Asunto(s)
Albendazol/uso terapéutico , Antihelmínticos/uso terapéutico , Quimioprevención/estadística & datos numéricos , Helmintiasis/prevención & control , Mebendazol/uso terapéutico , Albendazol/provisión & distribución , Animales , Antihelmínticos/provisión & distribución , Ascariasis/epidemiología , Ascariasis/parasitología , Ascariasis/prevención & control , Ascaris lumbricoides/fisiología , Helmintiasis/epidemiología , Helmintiasis/parasitología , Infecciones por Uncinaria/epidemiología , Infecciones por Uncinaria/parasitología , Infecciones por Uncinaria/prevención & control , Humanos , Mebendazol/provisión & distribución , Prevalencia , Suelo/parasitología , Tricuriasis/epidemiología , Tricuriasis/parasitología , Tricuriasis/prevención & control , Trichuris/fisiología
14.
Vet Parasitol Reg Stud Reports ; 17: 100316, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31303229

RESUMEN

Hookworm infection is globally prevalent among dogs and cats representing a major public health risk. Although previous studies have surveyed canine and feline hookworms in Guangzhou city, the status of these infection needs to be further explored in other regions of South China. To investigate the prevalence and zoonotic risk of canine and feline hookworms in eight cities (Guangzhou, Foshan, Shenzhen, Huizhou, Zhongshan, Shaoguan, Shantou and Chaozhou) of Guangdong province, China, we developed specific PCR methods based on ITS sequence for identifying three common hookworm species. The results showed that the prevalence of hookworms from stray dogs and cats was 20.23% (142/702) and 15.26% (47/308), respectively. The established PCR methods could identify Ancylostoma ceylanicum, A. caninum and A. tubaeforme. The mixed infections of A. caninum and A. ceylanicum were detected in stray dogs of Guangzhou and Shaoguan, with the rate of 8.3% and 21.2%, respectively. Among the stray dogs in Foshan, the infection rate of A. ceylanicum was higher than that of A. caninum. The stray cats in four of five investigated cities were infected with A. ceylanicum. The different region, age and rearing environments had an impact on the hookworm infection rates of stray dogs and cats. In conclusion, the reported higher infection rate of A. ceylanicum than other hookworm species in stray dogs and cats poses a potential risk to public health.


Asunto(s)
Ancylostomatoidea/clasificación , Enfermedades de los Gatos/epidemiología , Enfermedades de los Perros/epidemiología , Infecciones por Uncinaria/veterinaria , Zoonosis/epidemiología , Factores de Edad , Ancylostomatoidea/aislamiento & purificación , Animales , Enfermedades de los Gatos/parasitología , Gatos , China/epidemiología , ADN de Helmintos/aislamiento & purificación , Enfermedades de los Perros/parasitología , Perros , Heces/parasitología , Femenino , Infecciones por Uncinaria/epidemiología , Infecciones por Uncinaria/parasitología , Masculino , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Riesgo , Sensibilidad y Especificidad , Zoonosis/parasitología
15.
BMC Res Notes ; 12(1): 231, 2019 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-30992048

RESUMEN

OBJECTIVE: The aim of this study was to determine the prevalence of soil transmitted helminthes among primary school children. School based cross-sectional study design was employed. A total of six hundred study subjects were selected by a multistage sampling method. Fresh stool specimens were collected using clean, dry and wide mouthed labeled stool cups. It was processed by Kato-Katz technique. The data were analyzed using SPSS version 20 and p-value < 0.05 was considered statistically significant. RESULT: The overall prevalence of soil transmitted helminthes was 57 (9.5%). Hookworm was the most prevalent helminthes species isolated (4.2%) followed by A. lumbricoide (3%). The prevalence of Taenia species, T. trichiura, H. nana and E. vermicularis were; 1.2%, 0.5%, 0.7% and 0.8% respectively. The prevalence of the Soil transmitted helminthes infection was low and all cases of Soil transmitted infections in this study were with low infection intensity. This might be due to the preventive chemotherapy given to the school children.


Asunto(s)
Ancylostomatoidea/aislamiento & purificación , Ascariasis/epidemiología , Ascaris lumbricoides/aislamiento & purificación , Infecciones por Uncinaria/epidemiología , Taenia/aislamiento & purificación , Teniasis/epidemiología , Adolescente , Ancylostomatoidea/clasificación , Animales , Antihelmínticos/administración & dosificación , Ascariasis/parasitología , Ascariasis/prevención & control , Ascariasis/transmisión , Ascaris lumbricoides/clasificación , Niño , Preescolar , Estudios Transversales , Etiopía/epidemiología , Heces/parasitología , Femenino , Infecciones por Uncinaria/parasitología , Infecciones por Uncinaria/prevención & control , Infecciones por Uncinaria/transmisión , Humanos , Masculino , Profilaxis Pre-Exposición/métodos , Prevalencia , Instituciones Académicas , Suelo/parasitología , Taenia/clasificación , Teniasis/parasitología , Teniasis/prevención & control , Teniasis/transmisión
16.
Physiol Biochem Zool ; 92(3): 326-338, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30986114

RESUMEN

Parasites can cause chronic stress in some animal species, and this type of stress response has been associated with adverse consequences for the host. In order to know whether parasitism elicited a stress response associated with decreased host fitness, hookworm (Uncinaria sp.) infection was studied in a colony of South American fur seals (Arctocephalus australis) in which hookworms infect nearly all pups born in a reproductive season. A parasite-free group was generated by treating a subset of pups with an antiparasitic drug before they developed patent hookworm infection. Stress and metabolic hormones, energy balance, and humoral and cellular immune parameters were measured in this group and hookworm-infected pups. Hookworms elicited a marked increase in plasma cortisol levels in fur seal pups. These hookworm-infected pups were able to maintain constant glucose levels, despite losing body mass over the course of infection potentially because of increased protein catabolism. Infected pups were able to mount an effective immune response against the parasite and eliminated hookworms from the intestine, recovering partial body mass lost as a result of hookworm infection at the end of the study period. As shown in previous studies, adequate glucose levels are critical for proper T lymphocyte reactivity, and it is possible that, through activation of a stress response, energy can be readily available for immune response against the parasite contributing to early recovery from infection. Although there are potential fitness costs to mounting a sustained stress response, these could also be adaptive and promote survival during critical life-history stages.


Asunto(s)
Lobos Marinos/parasitología , Infecciones por Uncinaria/veterinaria , Estrés Fisiológico/inmunología , Ancylostomatoidea/genética , Ancylostomatoidea/aislamiento & purificación , Animales , Antiparasitarios/uso terapéutico , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Infecciones por Uncinaria/tratamiento farmacológico , Infecciones por Uncinaria/parasitología , Inmunidad Celular , Inmunidad Humoral , Ivermectina/uso terapéutico , Masculino
17.
J Helminthol ; 94: e43, 2019 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-30813972

RESUMEN

All canine hookworms are known to be zoonotic, causing infections ranging from transient skin irritations to prolonged 'creeping eruptions', eosinophilic enteritis and even patent intestinal infections. There is little information on canine hookworm species and their public health significance in sub-Saharan Africa. This study determined the prevalence and species of hookworms in dogs from different climatic zones of Kenya. Dog faecal samples were collected from the environment, and hookworm eggs were isolated by zinc chloride flotation and subjected to DNA extraction. Polymerase chain reaction (PCR) assays targeting the internal transcribed spacer (ITS) 1 and 2, 5.8S and 28S ribosomal RNA of Ancylostoma spp. and Uncinaria stenocephala were performed, and hookworm species were identified by PCR-restriction fragment length polymorphism (RFLP) or DNA sequencing. Hookworm eggs were detected by microscopy in 490/1621 (30.23%, 95% CI 28.01-32.54) faecal samples. Estimates of faecal prevalence were high in counties receiving higher rainfall (Narok 46.80%, Meru 44.88%) and low in those with a more arid climate (Isiolo 19.73%, Turkana 11.83%). In a subset of 70 faecal samples, Ancylostoma caninum (n = 59) was the most common species, followed by A. braziliense (n = 10) and A. cf. duodenale (n = 1). This study reports for the first time the detection of A. cf. duodenale in dog faeces and zoonotic hookworm species in Kenyan dogs. These findings emphasize the need for control measures such as enforcing laws for restraining stray dogs, regular deworming of dogs, and public health awareness programmes aimed at informing communities on outdoor use of footwear.


Asunto(s)
Ancylostomatoidea/aislamiento & purificación , Enfermedades de los Perros/parasitología , Infecciones por Uncinaria/veterinaria , Ancylostomatoidea/clasificación , Ancylostomatoidea/genética , Animales , Perros , Heces/parasitología , Femenino , Infecciones por Uncinaria/parasitología , Kenia , Masculino , Polimorfismo de Longitud del Fragmento de Restricción
18.
J Helminthol ; 94: e39, 2019 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-30789121

RESUMEN

There is a paucity of information on hookworm species in humans, domestic animals and wildlife in southern Africa. Our study aimed to identify hookworm species from stray dogs, humans, and selected wildlife from South Africa. A total of 356 faecal samples were screened for the presence of hookworm-like eggs and subsequently coproculture from the positive samples was carried out to obtain larvae. Hookworm-like eggs were detected in 23.03% (82/356) of samples. Of these samples, 78/296 were from dogs, 3/50 from humans and 1/10 from wildlife. DNA was then isolated from the larvae of 55 positive samples, which were subjected to polymerase chain reaction (PCR), polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequencing of the nuclear ribosomal internal transcribed spacer (ITS1) and 5.8S rRNA region. Presence of Ancylostoma caninum, A. braziliense and A. ceylanicum-like species was recorded in stray dogs and A. caninum was recorded in wildlife and humans, using PCR-RFLP. Although PCR-RFLP results pointed to the presence of A. ceylanicum, we did not get a sequence that matched with A. ceylanicum from GenBank. This may have been due to the low proportion of A. ceylanicum larvae in our samples. Twenty-two of the 27 positive amplicons from stray dogs matched with A. caninum, three with A. braziliense and two had mixed infections of A. braziliense and A. caninum. Sequences from a lion and three humans matched with A. caninum. This is the first confirmation of a patent A. caninum infection in humans as evidenced by the presence of eggs in faeces, with the subsequent larvae from coproculture being identified as A. caninum.


Asunto(s)
Ancylostomatoidea/aislamiento & purificación , Animales Salvajes/parasitología , Enfermedades de los Perros/parasitología , Infecciones por Uncinaria/parasitología , Infecciones por Uncinaria/veterinaria , Ancylostomatoidea/clasificación , Ancylostomatoidea/genética , Animales , ADN de Helmintos/genética , Perros , Heces/parasitología , Humanos , Larva/clasificación , Larva/genética , Leones/parasitología , Filogenia , Polimorfismo de Longitud del Fragmento de Restricción , Sudáfrica , Zoonosis/parasitología
19.
J Ethnopharmacol ; 235: 489-500, 2019 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-30763693

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The whole plant of Andrographis paniculata (Burm. f.) Wall.ex Nees is used traditionally in different forms by the local people of Asian countries owing to its myriad medicinal properties. Its use as an anthelmintic has been mentioned in literature but has not been well elucidated. AIM OF THE STUDY: To determine anthelmintic effects of extracts from leaves of A.paniculata against human hookworm species based on a standard assay system and to establish the effects of major active compounds responsible for the effects. MATERIALS AND METHODS: Ovicidal and larvicidal activities of extracts of leaves of A.paniculata in different solvents ethanol (Et), methanol (Met), ethyl acetate (EA) and petroleum ether (PE) was studied against field isolates of Ancylostoma duodenale collected and cultivated from hookworm infected human stool samples by egg hatch and larval motility assays. Major active compounds namely andrographolide (AP1), neoandrographolide (AP2) and andrograpanin (AP3) were estimated quantitatively in all the extracts by high-performance liquid chromatography (HPLC) and mass spectrometry (MS) analysis. Anthelmintic effects (ED50, LC50) and presence of the marker compounds in each extract was statistically analyzed by principal component analysis (PCA). Further, biological activities of pure compounds of AP1, AP2, AP3 were assessed to validate the results of the study. RESULTS: Extracts in ethanol and methanol showed highest activity in inhibition of egg hatching with lowest ED50 values (0.017 and 0.02 mg/mL respectively) while ethyl acetate extract had the highest activity against larval motility (0.001 mg/mL) followed by ethanol (0.019 mg/mL). On HPLC analysis, andrographolide content (%), the major diterpene compound, in Met and Et was 0.85 and 1.43 respectively. On PCA, andrographolide component in the extracts was associated with significant inhibitory effects both on egg hatching and larval motility. Pure compound AP1 also showed significant ovicidal and larvicidal activities at concentrations 0.125 µg/mL and 0.019 mg/mL respectively. CONCLUSION: Andrographolide is one of the main phytochemical responsible for significant ovicidal and larvicidal activity against field isolates of A.duodenale from human infections and can be developed as a potential therapeutic choice.


Asunto(s)
Ancylostoma/efectos de los fármacos , Andrographis/química , Infecciones por Uncinaria/tratamiento farmacológico , Extractos Vegetales/farmacología , Animales , Antihelmínticos/administración & dosificación , Antihelmínticos/aislamiento & purificación , Antihelmínticos/farmacología , Cromatografía Líquida de Alta Presión , Infecciones por Uncinaria/parasitología , Humanos , Dosificación Letal Mediana , Espectrometría de Masas , Extractos Vegetales/administración & dosificación , Hojas de la Planta , Análisis de Componente Principal , Solventes/química
20.
Int J Parasitol ; 49(5): 397-406, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30771359

RESUMEN

Soil-transmitted nematodes infect over a billion people and place several billion more at risk of infection. Hookworm disease is the most significant of these soil-transmitted nematodes, with over 500 million people infected. Hookworm infection can result in debilitating and sometimes fatal iron-deficiency anemia, which is particularly devastating in children and pregnant women. Currently, hookworms and other soil-transmitted nematodes are controlled by administration of a single dose of a benzimidazole to targeted populations in endemic areas. While effective, people are quickly re-infected, necessitating frequent treatment. Widespread exposure to anthelmintic drugs can place significant selective pressure on parasitic nematodes to generate resistance, which has severely compromised benzimidazole anthelmintics for control of livestock nematodes in many areas of the world. Here we report, to our knowledge, the first naturally occurring multidrug-resistant strain of the canine hookworm Ancylostoma caninum. We reveal that this isolate is resistant to fenbendazole at the clinical dosage of 50 mg/kg for 3 days. Our data shows that this strain harbors a fixed, single base pair mutation at amino acid 167 of the ß-tubulin isotype 1 gene, and by using CRISPR/Cas9 we demonstrate that introduction of this mutation into the corresponding amino acid in the orthologous ß-tubulin gene of Caenorhabditis elegans confers a similar level of resistance to thiabendazole. We also show that the isolate is resistant to the macrocyclic lactone anthelmintic ivermectin. Understanding the mechanism of anthelmintic resistance is important for rational design of control strategies to maintain the usefulness of current drugs, and to monitor the emergence of resistance. The isolate we describe represents the first multidrug-resistant strain of A. caninum reported, and our data reveal a resistance marker that can emerge naturally in response to heavy anthelminthic treatment.


Asunto(s)
Ancylostoma/efectos de los fármacos , Ancylostoma/aislamiento & purificación , Enfermedades de los Perros/parasitología , Resistencia a Medicamentos , Infecciones por Uncinaria/veterinaria , Ancylostoma/genética , Ancylostoma/crecimiento & desarrollo , Animales , Antihelmínticos/farmacología , Secuencia de Bases , Perros , Femenino , Proteínas del Helminto/genética , Infecciones por Uncinaria/parasitología , Ivermectina/farmacología , Masculino , Filogenia , Tiabendazol/farmacología , Tubulina (Proteína)/genética
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