RESUMEN
OBJECTIVES: This study evaluated the occurrence of Schistosoma mansoni and soil-transmitted helminths in an endemic area in the Eastern Brazilian Amazon, analysing prevalence and spatial distribution. METHODS: The study was conducted in four localities of Primavera Municipality, in Pará state. Data was obtained from the Decit 40/2012 project and the participants were divided into five age range categories for evaluation: children, adolescents, young adults, adults and elderly individuals. For the diagnostic tests, Kato-Katz slides were prepared to detect S. mansoni and soil-transmitted helminths eggs. The spatial distribution map and the Kernel Density Estimation were performed to assess the presence and location of infections. RESULTS: Stool samples revealed the presence of hookworms, S. mansoni, Ascaris lumbricoides and Trichuris trichiura eggs. Mono-, bi- and poly-parasitic infections were observed, with a significant prevalence of hookworm monoparasitism. CONCLUSIONS: The high frequency of children infected with soil-transmitted helminths confirms their significance as an ongoing public health problem in the poorest municipalities of Brazil. The Geographic Information System plays a crucial role in environmental surveillance and in the control of epidemics and endemic diseases, enabling accurate assessment and informed decision-making for their control.
Asunto(s)
Enfermedades Endémicas , Heces , Helmintiasis , Schistosoma mansoni , Esquistosomiasis mansoni , Suelo , Humanos , Brasil/epidemiología , Niño , Esquistosomiasis mansoni/epidemiología , Adolescente , Prevalencia , Animales , Suelo/parasitología , Adulto , Adulto Joven , Masculino , Heces/parasitología , Femenino , Schistosoma mansoni/aislamiento & purificación , Helmintiasis/epidemiología , Helmintiasis/transmisión , Preescolar , Análisis Espacial , Persona de Mediana Edad , Anciano , Sistemas de Información Geográfica , Ascaris lumbricoides/aislamiento & purificaciónRESUMEN
Infection caused by geo-helminth parasites are called geohelminthiasis are one of the global health problems. Vegetables eaten raw is the principal source of transmission of geo-helminth parasites. Pakistani people believe that eating raw vegetables are a significant source to get important vitamins and minerals. Based on the high incidence of pathogenic parasites and cultivating different vegetable types in the study areas, we conducted this study to evaluate the geo-helminth contamination of raw vegetables in northwest Khyber Pakhtunkhwa, Pakistan. This is a descriptive study comprised, 1942 samples of 25 various types of vegetables. The samples were examined in physiological saline solution using sedimentation and centrifugation methods. The findings were analyzed by Graph-Pad version 5. P value less than 0.05 (95% CI) was considered significant. Results showed that 16.5% (n=322) of all vegetables were contaminated with one or more type of geo-helminth parasites. Garlic was the highest (35%) and cauliflower the lowest (4%) contaminated samples respectively. Ascaris lumbricoides was the most common geo helminth found followed by hook worm species while Trichuris trichura was the least in all the vegetable samples. Leafy vegetables were highly contaminated 25.3% than vegetables with root parts 21.2% and fruity 9.09%. More than half of the contaminated vegetables were contaminated with single species of geo-helminth (P<0.05) while less than half with multiple types of geo-helminth contamination. Ninety two vegetables samples were contaminated with 2 species of parasites (P<0.05) and 45 with 3 (P>0.05) species of geo-helminth parasites. Education level of vendors and means of display were not significantly associated while types of vegetable used were significantly associated with the prevalence of parasites. The findings of this study provide evidence that consumption of raw [...].(AU)
As infecções causadas por parasitas geo-helmínticos são chamados de geohelmintíases e são um dos problemas de saúde globais. Os vegetais comidos crus são a principal fonte de transmissão dos parasitas geo-helmínticos. O povo paquistanês acredita que comer vegetais crus é uma fonte significativa para obter vitaminas e minerais importantes. Com base na alta incidência de parasitas patogênicos e no cultivo de diferentes tipos de vegetais nas áreas de estudo, conduzimos este estudo para avaliar a contaminação por geo-helmintos de vegetais crus no noroeste de Khyber Pakhtunkhwa, Paquistão. Trata-se de um estudo descritivo composto por 1942 amostras de 25 tipos diversos de vegetais. As amostras foram examinadas em solução salina fisiológica utilizando métodos de sedimentação e centrifugação. Os achados foram analisados pelo Graph-Pad versão 5. O valor de P menor que 0,05 (IC 95%) foi considerado significativo. Os resultados mostraram que 16,5% (n = 322) de todas as hortaliças estavam contaminadas com um ou mais tipos de parasitas geo-helmínticos. O alho foi a amostra mais contaminada (35%) e a couve-flor a menos (4%), respectivamente. Ascaris lumbricoides foi o geo-helmíntico mais comum encontrado, seguido por espécies de verme-anzol, enquanto Trichuris trichura foi o menos encontrado em todas as amostras de vegetais. Os vegetais folhosos foram altamente contaminados 25,3% do que os vegetais com partes de raiz 21,2% e frutados 9,09%. Mais da metade dos vegetais contaminados estavam contaminados com uma única espécie de geo-helmintos (P <0,05), enquanto menos da metade com vários tipos de contaminação com geo-helmintos. Noventa e duas amostras de vegetais estavam contaminadas com 2 espécies de parasitas (P <0,05) e 45 com 3 (P> 0,05) espécies de parasitas geo-helmínticos. O nível de escolaridade dos vendedores e os meios de exibição não [...].(AU)
Asunto(s)
Plantas/parasitología , Microbiología del Suelo , Contaminación Ambiental , Helmintiasis/epidemiología , Helmintiasis/transmisión , Ascaris , Trichuris , Saneamiento/normasRESUMEN
Infection caused by geo-helminth parasites are called geohelminthiasis are one of the global health problems. Vegetables eaten raw is the principal source of transmission of geo-helminth parasites. Pakistani people believe that eating raw vegetables are a significant source to get important vitamins and minerals. Based on the high incidence of pathogenic parasites and cultivating different vegetable types in the study areas, we conducted this study to evaluate the geo-helminth contamination of raw vegetables in northwest Khyber Pakhtunkhwa, Pakistan. This is a descriptive study comprised, 1942 samples of 25 various types of vegetables. The samples were examined in physiological saline solution using sedimentation and centrifugation methods. The findings were analyzed by Graph-Pad version 5. P value less than 0.05 (95% CI) was considered significant. Results showed that 16.5% (n=322) of all vegetables were contaminated with one or more type of geo-helminth parasites. Garlic was the highest (35%) and cauliflower the lowest (4%) contaminated samples respectively. Ascaris lumbricoides was the most common geo helminth found followed by hook worm species while Trichuris trichura was the least in all the vegetable samples. Leafy vegetables were highly contaminated 25.3% than vegetables with root parts 21.2% and fruity 9.09%. More than half of the contaminated vegetables were contaminated with single species of geo-helminth (P0.05) species of geo-helminth parasites. Education level of vendors and means of display were not significantly associated while types of vegetable used were significantly associated with the prevalence of parasites. The findings of this study provide evidence that consumption of raw [...].
As infecções causadas por parasitas geo-helmínticos são chamados de geohelmintíases e são um dos problemas de saúde globais. Os vegetais comidos crus são a principal fonte de transmissão dos parasitas geo-helmínticos. O povo paquistanês acredita que comer vegetais crus é uma fonte significativa para obter vitaminas e minerais importantes. Com base na alta incidência de parasitas patogênicos e no cultivo de diferentes tipos de vegetais nas áreas de estudo, conduzimos este estudo para avaliar a contaminação por geo-helmintos de vegetais crus no noroeste de Khyber Pakhtunkhwa, Paquistão. Trata-se de um estudo descritivo composto por 1942 amostras de 25 tipos diversos de vegetais. As amostras foram examinadas em solução salina fisiológica utilizando métodos de sedimentação e centrifugação. Os achados foram analisados pelo Graph-Pad versão 5. O valor de P menor que 0,05 (IC 95%) foi considerado significativo. Os resultados mostraram que 16,5% (n = 322) de todas as hortaliças estavam contaminadas com um ou mais tipos de parasitas geo-helmínticos. O alho foi a amostra mais contaminada (35%) e a couve-flor a menos (4%), respectivamente. Ascaris lumbricoides foi o geo-helmíntico mais comum encontrado, seguido por espécies de verme-anzol, enquanto Trichuris trichura foi o menos encontrado em todas as amostras de vegetais. Os vegetais folhosos foram altamente contaminados 25,3% do que os vegetais com partes de raiz 21,2% e frutados 9,09%. Mais da metade dos vegetais contaminados estavam contaminados com uma única espécie de geo-helmintos (P 0,05) espécies de parasitas geo-helmínticos. O nível de escolaridade dos vendedores e os meios de exibição não [...].
Asunto(s)
Ascaris , Helmintiasis/epidemiología , Helmintiasis/transmisión , Microbiología del Suelo , Plantas/parasitología , Contaminación Ambiental , Saneamiento/normas , TrichurisRESUMEN
BACKGROUND: There are few prospective longitudinal studies of soil-transmitted helminth (STH) infections during early childhood. We studied the epidemiology of and risk factors for soil-transmitted helminth infections from birth to 8 years of age in tropical Ecuador. METHODS: 2,404 newborns were followed to 8 years of age with periodic stool sample collections. Stool samples were collected also from household members at the time of the child's birth and examined by microscopy. Data on social, environmental, and demographic characteristics were collected by maternal questionnaire. Associations between potential risk factors and STH infections were estimated using generalized estimated equations applied to longitudinal binary outcomes for presence or absence of infections at collection times. RESULTS: Of 2,404 children, 1,120 (46.6%) were infected with at least one STH infection during the first 8 years of life. The risk of A. lumbricoides (16.2%) was greatest at 3 years, while risks of any STH (25.1%) and T. trichiura (16.5%) peaked at 5 years. Factors significantly associated with any STH infection in multivariable analyses included age, day-care (OR 1.34, 95% CI 1.03-1.73), maternal Afro-Ecuadorian ethnicity (non-Afro vs. Afro, OR 0.55, 95% CI 0.43-0.70) and lower educational level (secondary vs. illiterate, OR 0.31, 95% CI 0.22-0.45)), household overcrowding (OR 1.53, 95% CI 1.21-1.94)), having a latrine rather than a water closet (WC vs. latrine, OR 0.77, 95% CI 0.62-0.95)), and STH infections among household members (OR 2.03, 95% CI 1.59-2.58)). T. trichiura was more associated with poverty (high vs. low socioeconomic status, OR, 0.63, 95% CI 0.40-0.99)] and presence of infected siblings in the household (OR 3.42, 95% CI 2.24-5.22). CONCLUSION: STH infections, principally with A. lumbricoides and T. trichiura, peaked between 3 and 5 years in this cohort of children in tropical Ecuador. STH infections among household members were an important determinant of infection risk and could be targeted for control and elimination strategies.
Asunto(s)
Helmintiasis/epidemiología , Helmintiasis/transmisión , Suelo/parasitología , Animales , Cohorte de Nacimiento , Niño , Preescolar , Ecuador/epidemiología , Heces/parasitología , Femenino , Helmintiasis/economía , Helmintiasis/parasitología , Helmintos/clasificación , Helmintos/genética , Helmintos/aislamiento & purificación , Humanos , Lactante , Recién Nacido , Estudios Longitudinales , Masculino , Pobreza , Estudios ProspectivosRESUMEN
The role of the gut microbiota during coinfection with soil-transmitted helminths (STH) and Plasmodium spp. is poorly understood. We examined peripheral blood and fecal samples from 130 individuals who were either infected with Plasmodium vivax only, coinfected with P. vivax and STH, infected with STH alone, or not infected with either P. vivax or STH. In addition to a complete blood count (CBC) with differential, transcriptional profiling of peripheral blood samples was performed by transcriptome sequencing (RNA-Seq), fecal microbial communities were determined by 16S rRNA gene sequencing, and circulating cytokine levels were measured by bead-based immunoassays. Differences in blood cell counts, including an increased percentage of neutrophils, associated with a transcriptional signature of neutrophil activation, were driven primarily by P. vivax infection. P. vivax infection was also associated with increased levels of interleukin 6 (IL-6), IL-8, and IL-10; these cytokine levels were not affected by STH coinfection. Surprisingly, P. vivax infection was more strongly associated with differences in the microbiota than STH infection. Children infected with only P. vivax exhibited elevated Bacteroides and reduced Prevotella and Clostridiaceae levels, but these differences were not observed in individuals coinfected with STH. We also observed that P. vivax parasitemia was higher in the STH-infected population. When we used machine learning to identify the most important predictors of the P. vivax parasite burden (among P. vivax-infected individuals), bacterial taxa were the strongest predictors of parasitemia. In contrast, circulating transforming growth factor ß (TGF-ß) was the strongest predictor of the Trichuris trichiura egg burden. This study provides unexpected evidence that the gut microbiota may have a stronger link with P. vivax than with STH infection.IMPORTANCEPlasmodium (malaria) and helminth parasite coinfections are frequent, and both infections can be affected by the host gut microbiota. However, the relationship between coinfection and the gut microbiota is unclear. By performing comprehensive analyses on blood/stool samples from 130 individuals in Colombia, we found that the gut microbiota may have a stronger relationship with the number of P. vivax (malaria) parasites than with the number of helminth parasites infecting a host. Microbiota analysis identified more predictors of the P. vivax parasite burden, whereas analysis of blood samples identified predictors of the helminth parasite burden. These results were unexpected, because we expected each parasite to be associated with greater differences in its biological niche (blood for P. vivax and the intestine for helminths). Instead, we find that bacterial taxa were the strongest predictors of P. vivax parasitemia levels, while circulating TGF-ß levels were the strongest predictor of helminth parasite burdens.
Asunto(s)
Coinfección/inmunología , Coinfección/parasitología , Microbioma Gastrointestinal , Helmintiasis/inmunología , Malaria Vivax/inmunología , Adolescente , Animales , Bacterias/clasificación , Niño , Preescolar , Colombia , Estudios Transversales , Heces/microbiología , Femenino , Perfilación de la Expresión Génica , Helmintiasis/transmisión , Helmintos/inmunología , Humanos , Masculino , Plasmodium vivax/inmunología , RNA-Seq , Suelo/parasitologíaRESUMEN
BACKGROUND: Efforts to control soil-transmitted helminth (STH) infections have intensified over the past decade. Field-survey data on STH prevalence, infection intensity and drug efficacy is necessary to guide the implementation of control programs and should be of the best possible quality. METHODOLOGY: During four clinical trials designed to evaluate the efficacy of albendazole against STHs in Brazil, Ethiopia, Lao PDR and Tanzania, quality control (QC) was performed on the duplicate Kato-Katz thick smears and the data entry. We analyzed datasets following QC on both fecal egg counts (FECs) and data entry, and compared the prevalence of any STH infection and moderate-to-heavy intensity (MHI) infections and the drug efficacy against STH infections. RESULTS: Across the four study sites, a total of 450 out of 4,830 (9.3%) Kato-Katz thick smears were re-examined. Discrepancies in FECs varied from ~3% (hookworms) to ~6.5% (Ascaris lumbricoides and Trichuris trichiura). The difference in STH prevalence and prevalence of MHI infections using the datasets with and without QC of the FECs did not exceed 0.3%, except for hookworm infections in Tanzania, where we noted a 2.2 percentage point increase in MHI infections (pre-QC: 1.6% vs. post-QC: 3.8%). There was a 100% agreement in the classification of drug efficacy of albendazole against STH between the two datasets. In total, 201 of the 28,980 (0.65%) data entries that were made to digitize the FECs were different between both data-entry clerks. Nevertheless, the overall prevalence of STH, the prevalence of MHI infections and the classification of drug efficacy remained largely unaffected. CONCLUSION/SIGNIFICANCE: In these trials, where staff was informed that QC would take place, minimal changes in study outcomes were reported following QC on FECs or data entry. Nevertheless, imposing QC did reduce the number of errors. Therefore, application of QC together with proper training of the personnel and the availability of clear standard operating procedures is expected to support higher data quality.
Asunto(s)
Albendazol/uso terapéutico , Helmintiasis/tratamiento farmacológico , Control de Calidad , Ancylostomatoidea , Animales , Ascaris , Brasil/epidemiología , Ensayos Clínicos como Asunto , Etiopía/epidemiología , Heces/parasitología , Guías como Asunto , Helmintiasis/epidemiología , Helmintiasis/transmisión , Infecciones por Uncinaria/tratamiento farmacológico , Infecciones por Uncinaria/epidemiología , Humanos , Laos/epidemiología , Recuento de Huevos de Parásitos , Prevalencia , Suelo/parasitología , Tanzanía/epidemiología , TrichurisRESUMEN
BACKGROUND: Soil-transmitted helminth (STH) infections have many negative health outcomes (e.g., diarrhea, nutritional deficiencies) that can also exacerbate poverty. These infections are generally highest among low-income populations, many of which are also undergoing market integration (MI; increased participation in a market-based economy). Yet the direct impact of MI-related social and environmental changes on STH infection patterns is poorly understood, making it unclear which lifestyle factors should be targeted to better control disease spread. This cross-sectional study examines if household infrastructure associated with greater MI is associated with lower STH burdens among Indigenous Ecuadorian Shuar. METHODS: Kato-Katz fecal smears were used to determine STH infection status and intensity (n = 620 participants; 308 females, 312 males, aged 6 months-86 years); Ascaris lumbricoides (ascarid) and Trichuris trichiura (whipworm) were the primary infection types detected. Structured interviews assessing lifestyle patterns (e.g., measures of household infrastructure) measured participant MI. Multilevel regression analyses and zero-inflated negative binomial regression models tested associations between MI measures and STH infection status or intensity, controlling for individual and community characteristics. RESULTS: Participants residing in more market-integrated households exhibited lower infection rates and intensities than those in less market integrated households. Parasite infection status and T. trichiura infection intensity were lower among participants living in houses with wood floors than those with dirt floors, while individuals using well or piped water from a spring exhibited lower A. lumbricoides infection intensities compared to those using river or stream water. Unexpectedly, latrine type was not significantly related to STH infection status or intensity. These results suggest that sources of exposure differ between the two helminth species. CONCLUSIONS: This study documents associations between household measures and STH infection among an Indigenous population undergoing rapid MI. These findings can help healthcare programs better target interventions and reduce STH exposure among at-risk populations.
Asunto(s)
Heces/parasitología , Helmintiasis , Pobreza/estadística & datos numéricos , Suelo/parasitología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Ascariasis/epidemiología , Ascariasis/transmisión , Ascaris lumbricoides/aislamiento & purificación , Niño , Preescolar , Estudios Transversales , Ecuador/epidemiología , Composición Familiar , Femenino , Helmintiasis/epidemiología , Helmintiasis/transmisión , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Grupos de Población/estadística & datos numéricos , Prevalencia , Factores de Riesgo , Saneamiento/estadística & datos numéricos , Encuestas y Cuestionarios , Cuartos de Baño/estadística & datos numéricos , Tricuriasis/epidemiología , Tricuriasis/transmisión , Trichuris/aislamiento & purificación , Adulto JovenRESUMEN
BACKGROUND: This study aims to establish the prevalence of soil-transmitted helminth (STH) intestinal infections, nutritional status, and anemia in school children aged 7 to 10 years old in the biogeographic provinces of Colombia in 2012-2013. STH prevalence in the country has not been described within the last 30 years and it is needed in order to establish policies its control in the country. METHODOLOGY: National Survey of STH in school-aged children with a multistage stratified probability sampling was conducted. The overall prevalence and intensity of STH infection, as well as for each parasite, (A. lumbricoides, T. trichiura and hookworms) were calculated for the country and for each of the nine biogeographic provinces. PRINCIPAL FINDINGS: Stool samples were collected from 6045 children in eight out of nine biogeographic provinces. The combined prevalence of STH in the country was 29.6%. T. trichiura was the most prevalent helminth (18.4%), followed by A. lumbricoides (11.3%), and hookworms (6.4%). For A. lumbricoides and hookworms, the highest prevalence values were found in the Amazonía province (58.0% and 35.7%, respectively). Regarding STH intensity, most cases showed moderate intensity (41.3%) for A. lumbricoides, and light intensity, for T. trichiura and hookworms. The national prevalence of anemia in school-aged children was 14.2%, lowest in the Nor-Andina province (3.5%), and highest in the Territorios Insulares oceánicos del Caribe province (45.1%). SIGNIFICANCE: Colombia has a moderate risk of STH infection in school-aged populations, with considerable variation in the prevalence values among the biogeographic provinces. Like any public health issue, this problem should be handled with a comprehensive approach that involves deworming programs and strategies for STH control according to the specific epidemiological and socioeconomic conditions and sanitation service coverage in each biogeographic province. The program should be further supported by intersectoral action to improve living conditions, particularly the excreta disposal, promoted at municipality levels.
Asunto(s)
Helmintiasis/parasitología , Helmintiasis/transmisión , Helmintos/aislamiento & purificación , Suelo/parasitología , Animales , Niño , Colombia/epidemiología , Estudios Transversales , Heces/parasitología , Femenino , Helmintiasis/epidemiología , Helmintos/clasificación , Helmintos/genética , Humanos , Masculino , Prevalencia , Instituciones Académicas/estadística & datos numéricosRESUMEN
BACKGROUND: Soil-transmitted helminths (STHs) comprise a group of helminth parasites that are included in the list of Neglected Tropical Diseases and require a passage through the soil to become infective. Several studies have detected that infection with STHs are associated with certain socioeconomic, environmental and soil characteristics. In Argentina, the presence of these parasites has been detected through a few point studies conducted in localities from 11 of the 23 provinces that comprise the country. METHODS/PRINCIPAL FINDINGS: The most important characteristics previously associated with the presence of STHs were identified and ranked through the use of an expert survey and the Analytical Hierarchy Process (AHP) in order to construct a risk map of STHs specific for Argentina. Prevalence data from previous studies was used to validate the generated risk map. The map shows that half of Argentina, from the Central provinces to the North, contains localities with the characteristics necessary for the development of these parasites. CONCLUSIONS/SIGNIFICANCE: The predicted map should serve as a useful tool for guiding the identification of survey areas for the generation of baseline data, detecting hotspots of infection, planning and prioritizing areas for control interventions, and eventually performing post-implementation surveillance activities.
Asunto(s)
Helmintiasis/epidemiología , Helmintiasis/transmisión , Suelo/parasitología , Argentina/epidemiología , Humanos , Prevalencia , Factores de RiesgoRESUMEN
In the Bolivian Chaco, recent surveys documented a dramatic decrease in the prevalence of soil-transmitted helminth (STH) infections as compared with the 1980s after thirty years of preventive chemotherapy (PC). Concomitant immunological rearrangements are expected. Because nematode infections are associated with increased levels of circulating IgE and glycoprotein CD30 soluble form (sCD30), this study aims to evaluate changes in serological markers of T helper (Th)2-cells activity between 1987 (high STH prevalence) and 2013 (low STH prevalence) in rural communities in the Bolivian Chaco area. We collected 151 sera during two different surveys in 1987 (n = 65) and 2013 (n = 86) and measured the concentration of total IgE and sCD30 by immunoassays. We found a statistically significant age-independent decrease in the total IgE (P < 0.0001) and sCD30 (P < 0.0001) from 1987 to 2013. The significant decrease in serological Th2 markers (IgE and sCD30) between 1987 and 2013 is consistent with the drop in STH prevalence in this geographical area during the same period of time. Further studies might elucidate the clinical and epidemiological impact of these serological rearrangements.
Asunto(s)
Anticuerpos Antihelmínticos/sangre , Helmintiasis/epidemiología , Inmunoglobulina E/sangre , Antígeno Ki-1/sangre , Suelo/parasitología , Adulto , Bolivia/epidemiología , Femenino , Helmintiasis/transmisión , Humanos , MasculinoAsunto(s)
Humanos , Animales , Masculino , Femenino , Suelo/parasitología , Helmintiasis/prevención & control , Helmintos/efectos de los fármacos , Antihelmínticos/farmacología , Literatura de Revisión como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Metaanálisis como Asunto , Resultado del Tratamiento , Metaanálisis en Red , Revisiones Sistemáticas como Asunto , Helmintiasis/transmisiónRESUMEN
BACKGROUND: Because the success of deworming programs targeting soil-transmitted helminths (STHs) is evaluated through the periodically assessment of prevalence and infection intensities, the use of the correct diagnostic method is of utmost importance. The STH community has recently published for each phase of a deworming program the minimal criteria that a potential diagnostic method needs to meet, the so-called target product profiles (TPPs). METHODOLOGY: We compared the diagnostic performance of a single Kato-Katz (reference method) with that of other microscopy-based methods (duplicate Kato-Katz, Mini-FLOTAC and FECPAKG2) and one DNA-based method (qPCR) for the detection and quantification of STH infections in three drug efficacy trials in Ethiopia, Lao PDR, and Tanzania. Furthermore, we evaluated a selection of minimal diagnostic criteria of the TPPs. PRINCIPAL FINDINGS: All diagnostic methods showed a clinical sensitivity of ≥90% for all STH infections of moderate-to-heavy intensities. For infections of very low intensity, only qPCR resulted in a sensitivity that was superior to a single Kato-Katz for all STHs. Compared to the reference method, both Mini-FLOTAC and FECPAKG2 resulted in significantly lower fecal egg counts for some STHs, leading to a substantial underestimation of the infection intensity. For qPCR, there was a positive significant correlation between the egg counts of a single Kato-Katz and the DNA concentration. CONCLUSIONS/SIGNIFICANCE: Our results indicate that the diagnostic performance of a single Kato-Katz is underestimated by the community and that diagnostic specific thresholds to classify intensity of infection are warranted for Mini-FLOTAC, FECPAKG2 and qPCR. When we strictly apply the TPPs, Kato-Katz is the only microscopy-based method that meets the minimal diagnostic criteria for application in the planning, monitoring and evaluation phase of an STH program. qPCR is the only method that could be considered in the phase that aims to seek confirmation for cessation of program. TRIAL REGISTRATION: ClinicalTrials.gov NCT03465488.
Asunto(s)
Pruebas Diagnósticas de Rutina/métodos , Helmintiasis/parasitología , Helmintiasis/transmisión , Helmintos/aislamiento & purificación , Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Suelo/parasitología , Adolescente , Animales , Brasil , Niño , Pruebas Diagnósticas de Rutina/instrumentación , Etiopía/epidemiología , Heces/parasitología , Femenino , Helmintiasis/diagnóstico , Helmintiasis/epidemiología , Helmintos/genética , Humanos , Laos/epidemiología , Masculino , Microscopía , Técnicas de Diagnóstico Molecular/instrumentación , Recuento de Huevos de Parásitos/métodos , Prevalencia , Sensibilidad y Especificidad , Tanzanía/epidemiología , Organización Mundial de la SaludRESUMEN
Children in the Peruvian Amazon Basin are at risk of soil-transmitted helminths (STH) infections. This study aimed to determine the prevalence of STH infection in children from a rural Amazonian community of Peru and to elucidate epidemiological risk factors associated with its perpetuation while on a school-based deworming program with mebendazole. Stool samples of children aged 2-14 years and their mothers were analyzed through direct smear analysis, Kato-Katz, spontaneous sedimentation in tube, Baermann's method, and agar plate culture. A questionnaire was administered to collect epidemiological information of interest. Among 124 children, 25.8% had one or more STH. Individual prevalence rates were as follows: Ascaris lumbricoides, 16.1%; Strongyloides stercoralis, 10.5%; hookworm, 1.6%; and Trichuris trichiura, (1.6%). The prevalence of common STH (A. lumbricoides, T. trichiura, and hookworm) was higher among children aged 2-5 years than older children (31.6% versus 12.8%; P = 0.01). In terms of sanitation deficits, walking barefoot was significantly associated with STH infection (OR = 3.28; CI 95% = 1.11-12.07). Furthermore, STH-infected children more frequently had a mother who was concomitantly infected by STH than the non-STH-infected counterpart (36.4% versus 14.1%, P = 0.02). In conclusion, STH infection is highly prevalent in children from this Amazonian community despite routine deworming. Institutional health policies may include hygiene and sanitation improvements and screening/deworming of mothers to limit the dissemination of STH. Further studies are needed to address the social and epidemiological mechanics perpetuating these infections.
Asunto(s)
Heces/parasitología , Helmintiasis/epidemiología , Helmintiasis/transmisión , Población Rural , Suelo/parasitología , Adolescente , Animales , Antihelmínticos/uso terapéutico , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Masculino , Mebendazol/uso terapéutico , Madres , Perú/epidemiología , Prevalencia , Factores de Riesgo , SaneamientoRESUMEN
Os espaços coletivos com grande circulação de pessoas e animais tutelados ou errantes, como as praças públicas, podem gerar um problema para a saúde pública, uma vez que os animais podem eliminar fezes contaminadas por parasitos nesses locais, desempenhando um importante papel epidemiológico na transmissão de zoonoses parasitárias. Portanto, este trabalho teve como objetivo avaliar a contaminação por parasitos zoonóticos em dez praças públicas da cidade de Sousa, Paraíba, bem como avaliar o melhor método de diagnóstico de infestação ambiental por estes parasitas. Foram feitas coletas de solo em cinco pontos diferentes de cada praça, por raspagem superficial em quadrantes delimitados por 15 cm, sendo coletados 200g da parte central de cada ponto. Os métodos de diagnósticos utilizados foram Flutuação Simples, Sedimentação Simples, Faust e Centrífugo-Flutuação em Solução de Sacarose. Das praças avaliadas, 90% (9/10) obtiveram pelo menos uma amostra positiva. O gênero de parasito mais frequente foi Ancylostoma spp., presente em 70% (7/ 10) das praças analisadas; seguido por Strongyloides spp., coccídeos e Taenia spp., em 40% (4/10); Toxocara spp.,em 30% (3/10); eCystoisospora spp. e Trichuris spp., em 10% (1/10). O método de Sedimentação Simples foi o mais eficaz, resultando em 44% (22/50) de amostras positivas. Os demais métodos não atingiram 15% de positividade. Concluiu-se que as praças públicas analisadas encontram-se altamente infestadas por parasitos zoonóticos, representando um risco a saúde pública no município de Sousa-PB.
Collective spaces with large circulation of people and animals domiciled or wandering, such as public squares, can generate a public health problem, since the animals can eliminate feces contaminated by parasites in these places, playing an important epidemiological role for zoonose transmission. Therefore, the objective of this work was to evaluate the contamination by zoonotic parasites in ten public squares of the city of Sousa, Paraíba, as well as to evaluate the best method for the diagnosis of environmental infestation by these parasites. Soil samples were collected at five different points of each square, by surface scraping in quadrants delimited by 15 cm, with 200g of the central part of each point being collected. The diagnostic methods used were Simple Flotation, Simple Sedimentation, Faust and Centrifugal-Fluctuation in Sucrose Solution. At least one positive sample in 90% (9/10) of the evaluated squares. The most frequent parasite genus was Ancylostoma spp., present in 70% (7/10) of the analyzed squares; followed by Strongyloides spp., coccidia and Taenia spp., in 40% (4/10); Toxocara spp., in 30% (3/10); and Cystoisospora spp. and Trichurisspp., in 10% (1/10). The Simple Sedimentation method was the most effective, resulting in 44% (22/50) of positive samples. The other methods did not reach 15% positivity. It was concluded that the analyzed public squares are highly infested by zoonotic parasites, representing a public health risk in the municipality of Sousa-PB.
Asunto(s)
Parásitos/aislamiento & purificación , Zoonosis/transmisión , Control de Enfermedades Transmisibles , Carga de Parásitos/estadística & datos numéricos , Toxocariasis/transmisión , Helmintiasis/transmisión , Anquilostomiasis/transmisiónRESUMEN
Despite the reduction in the prevalence of soil-transmitted helminthiases in many regions of the world, morbidity rates remain high in some rural regions. The Kato-Katz technique is a simple, inexpensive and field-applicable tool commonly used for the diagnosis and worm-burden characterization of these infections. Molecular studies have revolutionized our understanding of the epidemiology and evolutionary genetics of parasites. In this study we recovered helminthic DNA from Kato-Katz slides (n = 93) prepared in 2011 in the Brazilian Amazon. We achieved DNA recovery by polymerase chain reaction (PCR) in 84% of cases for Ascaris sp. and 75% of cases for hookworms. The sequencing confirmed the specific species of the amplicons. The slides stored for a few years could be analysed using this methodology, allowing access to DNA from a large collection of samples. We must consider the Kato-Katz thick smears as a source of helminth DNA. This can significantly reduce logistical difficulties in the field in terms of obtaining, preserving, transporting and initial processing of samples.
Asunto(s)
ADN de Helmintos/genética , Heces/parasitología , Helmintiasis/parasitología , Helmintos/aislamiento & purificación , Recuento de Huevos de Parásitos/métodos , Suelo/parasitología , Animales , Brasil , Helmintiasis/diagnóstico , Helmintiasis/transmisión , Helmintos/clasificación , Helmintos/genética , HumanosRESUMEN
This study aims to describe the prevalence, distribution, and factors associated with soil-transmitted helminthiases (STHs) in rural localities in Piaui, Brazil. Two cross-sectional surveys (n=605 subjects; 172 families) were carried out in order to obtain socio-demographic, anthropometric, spatial and parasitological data. Parasites were evaluated using Kato-Katz and centrifugal sedimentation techniques. Eggs were measured to assess infection with zoonotic Strongylida parasites. Kernel maps were constructed with Q-GIS. The prevalence of hookworm infection was 12.4% (75/605). Other helminthes found were Trichuris trichiura (n=1; 0.2%) and Hymenolepis nana (n=1; 0.2%). The hookworm positivity rate was significantly lower among subjects who had used albendazole when compared with individuals who had not used anthelmintics or had used antiprotozoal drugs in the last 6 months (8/134 [6.0%] vs. 59/415 [14.2%]; p=0.009). A total of 39/172 (22.7%) families had at least one infected member. The association between the number of dwellers and hookworm positivity in the family was present in a logistic regression multivariate model. Assessment of worm burdens showed 92.2% light, 6.2% moderate, and 1.6% heavy infections. Hookworm eggs (n=34) measured 57.2 - 75.4 µm in length and 36.4 - 44.2 µm in width (mean ± SD = 65.86 ± 4.66 µm L and 40.05 ± 1.99 µm W), commensurate with human hookworms. Hotspots suggest that transmission has a focal pattern. STHs persist in impoverished rural areas in Northeastern Brazil where currently available control strategies (mass drug administration) apparently do not allow the elimination of the infection.
Asunto(s)
Helmintiasis/epidemiología , Suelo/parasitología , Adolescente , Adulto , Brasil/epidemiología , Niño , Preescolar , Estudios Transversales , Heces/parasitología , Femenino , Helmintiasis/diagnóstico , Helmintiasis/parasitología , Helmintiasis/transmisión , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Áreas de Pobreza , Prevalencia , Población Rural , Índice de Severidad de la Enfermedad , Factores Socioeconómicos , Adulto JovenRESUMEN
OBJECTIVE: The estimation of prevalence and intensity of soil-transmitted helminth (STH) infections at a country-level is an essential prerequisite for the implementation of a rational control programme. The aim of this present study was to estimate the prevalence and distribution of STH infections and malnutrition in school-age children in rural areas of Ecuador. DESIGN: Cross-sectional study from October 2011 to May 2012. SETTING: Eighteen rural schools were randomly selected from the three ecological regions of Ecuador (coastal, highlands and Amazon basin). PARTICIPANTS: 920 children aged 6-16 years. MAIN OUTCOME MEASURES: Prevalence and intensity of STH infections associated with malnutrition (thinness/wasting or stunting). RESULTS: The results showed that 257 (27.9%) children were infected with at least one STH parasite. The prevalence of Trichuris trichiura, Ascaris lumbricoides and hookworm was 19.3%, 18.5% and 5.0%, respectively. Malnutrition was present in 14.2% of children and most common was stunting (12.3%). Compared with other regions, schoolchildren in the Amazon region had the highest STH prevalence (58.9%) of which a greater proportion of infections were moderate/heavy intensity (45.6%) and had the highest prevalence of malnutrition (20.4%). A positive association was observed between moderate to heavy infections with A. lumbricoides and malnutrition (adjusted OR 1.85, 95% CI 1.04 to 3.31, p=0.037). CONCLUSIONS: Our estimate of the prevalence of STH infections of 27.9% at a national level in Ecuador is lower than suggested by previous studies. Our data indicate that schoolchildren living in the Amazon region have a greater risk of STH infection and stunting compared with children from other regions. The implementation of school-based preventive chemotherapy and nutritional supplement programmes within the Amazon region should be prioritised. Long-term control strategies require improvements in water, sanitation and hygiene.
Asunto(s)
Helmintiasis , Estado Nutricional , Microbiología del Suelo , Adolescente , Animales , Niño , Estudios Transversales , Ecuador , Heces , Femenino , Helmintiasis/prevención & control , Helmintiasis/transmisión , Humanos , Masculino , Prevalencia , Suelo , Encuestas y CuestionariosRESUMEN
Soil-transmitted helminth (STH) infections are a global health issue affecting nearly one-third of the world's population. As most endemic areas of STH are impoverished countries or regions with limited healthcare resources, the accurate diagnosis of STH requires analytical tools that are not only quantitative, but also portable, inexpensive, and with no or minimal demand for external instrument. Herein, we introduce a novel paper-based diagnostic device, termed quantitative paper-based DNA reader (qPDR), capable of quantifying STH at the molecular level by measuring distance as readout, thus eliminating the need for external readers. On the basis of the unique interfacial interaction of a DNA intercalating dye, SYBR Green I, with native cellulose on a chromatographic paper, qPDR allows the distance-based quantification of minute amounts of double-stranded DNA as short as 6 min. By integrating qPDR with polymerase chain reactions that were performed using a smartphone-controlled portable thermal cycler, we were able to quantify minute amount of genetic markers from adult worms of an STH (Trichuris trichiura) that were expelled post-treatment by infected children living in the rural areas of Honduras.
Asunto(s)
ADN de Helmintos/genética , Helmintiasis/diagnóstico , Suelo/parasitología , Animales , Benzotiazoles , Diaminas , Marcadores Genéticos , Helmintiasis/genética , Helmintiasis/transmisión , Honduras , Humanos , Sustancias Intercalantes , Compuestos Orgánicos , Papel , Sistemas de Atención de Punto , Quinolinas , Trichuris/genética , Trichuris/aislamiento & purificaciónRESUMEN
A ocorrência de doenças parasitárias associadas ao consumo de pescado no Brasil geralmente passa desapercebida devido à baixa gravidade de seus sintomas e ao seu pouco conhecimento pelos médicos, inspetores sanitários e consumidores. Mais além, seu estudo é dificultado pela não obrigatoriedade de sua notificação, à escassez e pouca acurácia dos dados estatísticos disponíveis. Este trabalho apresenta uma atualização da incidência e epidemiologia das principais ictiozoonoses parasitárias associadas ao consumo de pescado em nosso país, com base numa minuciosa revisão bibliográfica. O resultado sugere que o perigo potencial destas doenças é alto, tendo em vista a descrição frequente da presença dos parasitas a elas associados em espécies de pescado de importância comercial consumidas no país. Entretanto, os dados disponíveis mostram a ocorrência de um número reduzido de casos, indicando seu baixo risco. A difilobotríase e a fagicolose são as principais ictiozoonoses presentes, ambas descritas recentemente e associadas ao consumo de pescado cru, mal cozido ou processado. A angiostrongilíase surge como uma ictiozoonose negligenciada emergente.(AU)
The occurrence of fish-borne parasitic diseases in Brazil generally passes unperceived due to the low seriousness of its symptoms and that they are little known by physicians, food inspectors and consumers. lts study is difficulted by the fact that the register of their occurrence is not mandatory as well as the poor quantity and quality of available statistical data. This paper presents an update of the incidence and epidemiology of the main parasitic fish-borne diseases in Brazil based on a comprehensive bibliography survey. The result suggests that the potential hazard of these diseases is high, taking into account the frequent description of the causative agents in fish species commonly commercialized within the country. Nevertheless, available data show a reduced number of human cases, indicating that the risk of fish-borne diseases is quite low. Diphyllobothriasis and fagicolosis are the main parasitic ictiozoonosis present, both recently described and associated with the consumption of raw, inadequately cooked or processed fish. Angiotrongyliasis appears as an emergent neglected ictiozoonosis.(AU)
Asunto(s)
Humanos , Animales , Enfermedades Parasitarias/epidemiología , Enfermedades Parasitarias/parasitología , Enfermedades Parasitarias/transmisión , Peces/parasitología , Helmintiasis/transmisión , Enfermedades Transmitidas por los Alimentos/parasitología , Zoonosis , Factores de RiesgoRESUMEN
Soil-transmitted helminth (STH) infections are widely distributed in tropical and subtropical areas, including Brazil. We performed a nationwide population-based study including all deaths in Brazil from 2000 to 2011, in which STHs (ascariasis, trichuriasis and/or hookworm infection) were mentioned on death certificates, either as underlying or as associated causes of death. Epidemiological characteristics, time trends and spatial analysis of STH-related mortality were analysed. STHs was identified on 853/12 491 280 death certificates: 827 (97·0%) deaths related to ascariasis, 25 (2·9%) to hookworm infections, and 1 (0·1%) to trichuriasis. The average annual age-adjusted mortality rate was 0·34/1 000 000 inhabitants (95% confidence interval: 0·27-0·44). Females, children <10 years of age, indigenous ethnic groups and residents in the Northeast region had highest STH-related mortality rates. Nationwide mortality decreased significantly over time (annual percent change: -5·7%; 95% CI: -6·9 to -4·4), with regional differences. We identified spatial high-risk clusters for STH-related mortality mainly in the North, Northeast and South regions. Diseases of the digestive system and infectious/parasitic diseases were the most commonly associated causes of death mentioned in the STH-related deaths. Despite decreasing mortality in Brazil, a considerable number of deaths is caused by STHs, with ascariasis responsible for the vast majority. There were marked regional differences, affecting mainly children and vulnerable populations.