Standardization of molecular techniques for the detection and characterization of intestinal protozoa and other pathogens in humans

Background: The intrinsic sensitivity limitations of basic parasitological methods, along with the particular biological characteristics of parasites, make these methods ineffective to differentiate morphologically indistinguishable species. Molecular detection and characterization techniques could be used to overcome these problems. The purpose of this work was to standardize molecular polymerase chain reaction (PCR) techniques, described in the literature, for the detection and molecular characterization of intestinal protozoa and other pathogens in humans. Methods: DNA was extracted from human or animal feces, previously washed or cultured in Boeck Drbohlav's Modified Medium. DNA extraction was performed with Machery-Nagel extraction kits. The standardization of the PCR, nested-PCR or RFLP techniques was carried out according to the literature. For each molecular technique performed, the sensitivity of the test was determined based on the minimun quantity required of DNA (sensitivity A) and the minimum quantity of life forms that the test detected (sensitivity B). Results: Sensitivity A was 10 fg for G. duodenalis, 12.5 pg for Entamoeba histolytica or Entamoeba dispar, 50 fg for Cryptosporidium spp., 225 pg for Cyclospora spp. and 800 fg or 8 fg for Blastocystis spp. after performing a 1780 bp PCR or 310 bp nested PCR, respectively. The sensitivity B was 100 cysts for G. duodenalis, 500 cysts for E. histolytica or E. dispar, 1000 oocysts for Cyclospora spp. and 3600 or four vegetatives forms for PCR or nested PCR of Blastocystis spp., respectively. Conclusions: The molecular detection of protozoa and chromist was achieved and the molecular characterization allowed the genotyping of some of the parasites such as Giardia duodenalis, Cryptosporidium spp., and Blastocystis spp. This study summarizes the molecular techniques for epidemiological studies in humans and animals, and helps in the investigation of their transmission sources in countries where intestinal parasites are a public health problem.(AU)

Prevalence of intestinal protozoan infections among rural children in Henan Province from 2014 to 2015 / 中国血吸虫病防治杂志

Objective To investigate the prevalence and influencing factors of intestinal protozoan infections among rural children in Henan Province. Methods A total of 104 survey sites were sampled from 35 counties (cities) in Henan Province using the stratified cluster sampling method to investigate the prevalence of intestinal protozoan infections among rural children from 2014 to 2015. The trophozoites and cysts of intestinal protozoa were identified using the iodine staining method and the physiological saline direct smear method (one detection for one stool sample). The prevalence of intestinal protozoan infections was compared among rural children with different characteristics, and the factors affecting intestinal protozoan infections among rural children were identified. Results The overall prevalence of intestinal protozoan infections was 0.60% (40/6 771) among rural children in Henan Province from 2014 to 2015. There were 7 species of intestinal protozoa identified, and there was no species-specific prevalence (χ2 = 37.732, P = 0.000). No significant differences were found in prevalence of intestinal protozoan infections among rural children in terms of gender (χ2 = 1.793, P = 0.181), age (χ2 = 1.443, P = 0.486), occupation (χ2 = 0.219, P = 0.896) or ecological region (χ2 = 1.700, P = 0.637). In addition, terrain (χ2 = 2.311, P = 0.510), economic level (χ2 = 4.322, P = 0.229), source of drinking water (χ2 = 0.731, P = 0.393), eating raw vegetables (χ2 = 1.134, P = 0.287) and deworming (χ2 = 1.089, P = 0.297) had no remarkable effects on the prevalence of intestinal protozoan infections among rural children in Henan Province; however, the prevalence of intestinal protozoan infections varied significantly among rural children living in regions with different coverage of non-harmless toilets (χ2 = 10.050, P = 0.018). Conclusion The prevalence of intestinal protozoan infections is low among rural children in Henan Province.

Progress of researches on traveler’s diarrhea caused by parasitic infections / 中国血吸虫病防治杂志

With the rapid development of global tourism, traveling gradually becomes an important part of daily lives, and travelers’health is paid more and more attention. Traveler’s diarrhea (TD) is one of the most common diseases among international or trans-regional travelers, which causes great disease and economic burdens. Currently, there is still a lack of systematic studies on the correlation between parasites and TD. The review mainly summarizes intestinal protozoa and helminth infections among patients with TD, so as to provide insights into the development of the control measures for parasitic diseases associated with TD and the prevention of risk factors before the journey to and during the journey of the areas endemic for parasitic diseases.

Intestinal protozoan infections among Egyptian neutropenic patients with acute leukemia

@#Several enteric protozoan species are linked to diarrhea in humans, with some causing debilitating illnesses, essentially in immunocompromised and neutropenic patients as in acute leukemias. The aim of this study was to detect intestinal protozoa in Egyptian neutropenic patients with acute leukemia. The study comprised two groups; 40 newly diagnosed neutropenic acute leukemia patients and 30 controls. Stool samples were collected from all participants and subjected to routine microscopic examination, special staining and detection of copro-antigen using rapid diagnostic test (RDT) RIDA®QUICK Entamoeba/ Giardia/ Cryptosporidium Combi. Cases were tested post-chemotherapy at the nadir of neutropenia (absolute neutrophil count ANC< 0.5x109/L) and 19 cases were also tested initially prior to chemotherapy. Of examined patients, 15/40 (37%) were positive for Blastocystis hominis by wet mount, 10/40 (25%) had microsporidia using modified trichrome stain and only 2 cases (5%) of Cryptosporidium spp. by Ziehl-Neelsen stain. By RDT, 8/40 cases (20%) were positive compared to entirely negative controls. The positive cases included 4 patients with G. intestinalis 2 with Entamoeba and 2 with Cryptosporidium.19/40 cases were tested both pre- and post-chemotherapy. microsporidian spp. was diagnosed in 6/19 cases at the nadir of neutropenia compared to none of the cases pre-chemotherapy and the difference was statistically significant (p= 0.031*). Intestinal protozoa in acute leukemia patients post-chemotherapy are common especially B. hominis. Furthermore, RDT might be helpful for diagnosing intestinal protozoa in acute leukemia. Attention is highly required as intestinal protozoa infection can emerge after chemotherapy such as microsporidia.

Eimeria bateri Natural Infection: Oocysts Reductions in Grey Quail (Coturnix coturnix) Treated with Bacillus thuringensis var. israelensis

Abstract Coccidiosis, a disease caused by the parasitic Eimeria spp., affects birds of all ages, particularly young birds more intensely. Infected poultry presents significant economic losses. Bacillus thuringiensis var israelensis (Bti) is a Gram-positive, spore-forming bacterium that produces proteins with high specific parasiticidal activity against various orders of parasites. Thus, the aim of the present study was to evaluate the parasiticidal potential of Bti in quails that were naturally infected with Eimeria bateri. Twenty 12-week-old male quails (Coturnix coturnix coturnix), naturally infected with Eimeria bateri, were randomly divided into two groups of 10 birds: Bti treated and control. The treated group was supplemented with Bti (1×108 spores∙g-1) in the feed, while; the control group received the same feed without Bti. To evaluate the occurrence of oocysts, samples of feces were collected every week for four weeks. Significant (P < 0.05) oocysts reductions of 56.64% and 94.51% were noted in the Bti treated group at 2nd and 4th week of study, respectively. The Bti supplementation may contribute to the reduction of oocysts in quails and environmental contamination. Bacillus thuringiensis var israelensis appeared to be a promising complementary alternative in E. bateri control.

Survey of human intestinal protozoal infections in Tibet Autonomous Region, 2015 / 中国血吸虫病防治杂志

Objective To investigate the current prevalence of human intestinal protozoal infections in Tibet Autonomous Region, so as to provide the scientific basis for the development of the future control strategy. Methods The study sites were sampled using a stratified cluster random sampling method in different ecological zones and different geographical locations of Tibet Autonomous Region in 2015. Fecal samples were collected from the permanent residents at ages of 3 years and older for the detection of intestinal protozoa cysts and trophozoites. The region-, gender-, age-, occupation- and education level-specific prevalence of human intestinal protozoal infections was estimated and compared. Results A total of 70 study sites were sampled from 23 counties (districts) in 3 ecological zones of Tibet Autonomous Region in 2015. Among 17 939 subjects surveyed, there were 1 117 residents infected with intestinal protozoa, with a prevalence of 6.23%. There were 9 species of intestinal protozoa identified, and Entamoeba coli (3.59%), Giardia lamblia (0.74%) and Blastocystis hominis (0.72%) were found to have a high in- fection rate. The prevalence of human intestinal protozoal infections was 7.20%, 6.39% and 4.48% in the southern, eastern and northern Tibetan ecological zones, respectively. Among the 23 counties (districts), the highest human prevalence was seen in Baingoin (13.56%) and Amdo counties (12.77%), and there were significant differences in the prevalence of human intestinal pro- tozoal infections among the three ecological zones (χ2 = 33.909, P < 0.01) and 23 counties (districts) (χ2 = 580.511, P < 0.01). There was no gender-specific prevalence of human intestinal protozoal infections (men, 6.08%; women, 6.35%; χ2 = 0.542, P > 0.05); however, there was age-specific human prevalence (χ2 = 44.377, P < 0.01), and a higher prevalence was seen in residents at ages of 60－69 years (8.51%) and 50－59 years (7.67%). In addition, there were occupation- (χ2 = 37.568, P < 0.01) and education level-specific prevalence rates of human intestinal protozoal infections (χ2 = 14.659, P < 0.01), and a higher prevalence was seen in farmers (7.17%) and herdsmen (5.28%), and in residents with a primary school education (6.62% and illiterate resi- dents (6.33%). Conclusions The prevalence of human intestinal protozoal infections remains high in Tibet Autonomous Region. The health education pertaining to intestinal parasitic disease control requires to be intensified among farmers and herds- men in rural areas.

Frequência de enteroparasitos em mulheres não grávidas e seus filhos e grávidas atendidas em uma unidade de saúde / Frequency of enteroparasites in non-pregnant women and their children and pregnant women attended at a public health unit

As infecções parasitárias intestinais são amplamente distribuídas em todo o mundo e a população infantil é a mais afetada. A prevalência das infecções parasitárias intestinais materna e infantil de pacientes atendidos em uma unidade de saúde pública do município de Lagoa Santa, Minas Gerais foi avaliada pela técnica de centrífugo sedimentação em formol-éter. A positividade foi de 41,7% para gestantes, 37,3% para mães e 35,7% em crianças. Endolimax nana (17,1%) e Giardia intestinalis (17,1%) foram os parasitos mais frequentemente detectados em crianças com idade inferior a dois anos e em gestantes (33,3%). Para as mães, G. intestinalis (20,3%) foi o parasito mais prevalente seguido de Entamoeba coli (17%). A infecção simultânea de mãe e filho foi detectada em 7 das 25 crianças infectadas. Apesar das ações de educação em saúde, melhoria no nível educacional e acesso a serviços médicos, a frequência de infecções por endoparasitas permanece alta. A literatura é escassa em relação ao tema e acredita-se que a deficiência na aplicação de medidas de educação sanitária possa fazer com que mães infectadas possam contribuir para a infecção parasitária de seus filhos, assim como os filhos podem ser fonte de infecção para suas mães.

Intestinal parasitic infections are widely distributed throughout the world and children are the most affected population. The objective of the present study was to evaluate the prevalence of parasitic maternal and infant intestinal infection of patients attended at a public health unit in the municipality of Lagoa Santa, Minas Gerais. The centrifugal-sedimentation in formol-ether was the technica used for stool analysis. Positivity was observed in 41.7% for pregnant women, 37.3% for mothers and 35.7% for children. Endolimax nana (17.1%) and Giardia intestinalis (17.1%) were the most frequently detected parasites in children under two-years old and pregnant women (33.3%). For mothers, G. intestinalis (20.3%) was the most prevalent parasite followed by Entamoeba coli (17%). Simultaneous infection of mother and child was detected in 7 of 25 infected children. Despite health educations actions, improvement in educational level, and access to medical services, the frequency of endoparasite infections remains high. Literature is scarce in relation to the present theme and it is believed that infected mothers can contribute for parasitic infection of their kids, just as children can be a source of infection for their mothers.

Progress of research on the interplay between helminth and intestinal protozoa and gut microbiota / 中国血吸虫病防治杂志

As the largest and most complex ecosystem in humans, gut microbiota resides in human or animal gastrointestinal tract with intestinal viruses and parasites. Previous studies have demonstrated that gut microbiotadysbiosis is strongly correlated with the development, progression and prognosis of multiple diseases. The parasites that are colonized in the host, may directly or indirectly affect gut microbiota and the gut microbiota-host homeostasis, and changes in the composition and diversity of gut microbiota may also affect parasitic infections and the development, progression and prognosis of parasitic diseases. This paper reviews the progress of research on the interplay between helminth and intestinal protozoa and gut microbiota.

Prevalence and associated factors of intestinal parasitic infections among asymptomatic food handlers working at Haramaya University cafeterias, eastern Ethiopia

BACKGROUND: Intestinal parasitic infections are major public health problems worldwide, with high prevalence in low income countries where substandard food hygiene practices are common. Asymptomatic food handlers with poor personal hygiene could be potential sources of parasitic infections. This study was aimed to assess the prevalence of intestinal parasitic infections and associated factors among asymptomatic food handlers working at Haramaya University cafeterias, eastern Ethiopia. METHODS: A cross-sectional study was conducted among asymptomatic food handlers working at Haramaya University cafeterias from August 2015 to January 2016. Population proportion to size allocation and systematic random sampling techniques were used to identify the study participants. Stool samples were collected and examined simultaneouly using direct and modified formol ether concentration wet smear techniques. Data were entered and analyzed using SPSS version 20.0 software. Logistic regressions were applied to assess association between independent variable and intestinal parasitic infections. Statistical significance was declared at a p-value less than 0.05. RESULTS: A total of 417 asymptomatic food handlers were enrolled in this study. Of these, females comprised 79.4%. Large proportion (39.3%) of food handlers were in the age group of 31–40 years. The overall prevalence of intestinal parasitic infections was 25.2% (95% CI: 18.3, 29.6). Entamoeba histolytica/ dispar (46.7%) and A. lumbricoides (14.3%) were the most frequent isolates. Having no formal education [AOR: 2.13, 95% CI: 1.24, 3.67], monthly income of less than 45.7 USD [AOR: 3.86, 95% CI: 1.62, 9.20], lack of hand washing after the use of the toilet with soap [AOR: 2.43, 95% CI: 1.22, 4.86] and untrimmed fingernails [AOR: 3.31, 95% CI: 1.99, 5.49] have significant association with intestinal parasitic infections. CONCLUSIONS: The high prevalence of intestinal parasitic infections in this study highlights the importance of food handlers as probable sources of parasitic infections. Public health measures and sanitation programs should be strengthened to control the spread of intestinal parasitic infections.

Parasitosis intestinales en Altragracia de la Montaña, Estado Miranda, Venezuela: Influencia del programa para la eliminación de oncocercosis / Intestinal parasites in Altragracia de la Montaña, Miranda State, Venezuela: Influence of the program for onchocerciasis elimination

El objetivo general de este trabajo fue determinar la prevalencia de parasitosis intestinales y sus características epidemiológicas en cuatro comunidades de la parroquia Altagracia de la Montaña, Estado Miranda (Venezuela). Se desarrolló un estudio de corte transversal con una muestra constituida por 492 en su mayoría niños, en febrero de 2011. Previo consentimiento informado, se realizó una encuesta clínico-epidemiológica, extracción de sangre y exámenes coproparasitológicos con los métodos directo, Kato y cultivo en agar. El 60% de la población tenía al menos un parásito de transmisión hídrica y/o alimentos contaminados por heces de humanos y/o animales. La elevada frecuencia de protozoarios intestinales, especialmente Blastocystis sp., con predominio entre quienes viven con fallas en la disposición de excretas y baja calidad del agua para consumo humano, demuestran la persistencia de parasitosis intestinales como problema de salud pública; sin embargo, la influencia indirecta de la administración semestral de ivermectina y educación sanitaria con visión etnográfica impartida por el Programa para la Eliminación de Oncocercosis en Bucarito, una de las comunidades evaluadas, tuvo como efecto colateral no sólo disminuir la prevalencia de helmintos intestinales, sino de los protozoarios, a pesar de estar sometida a los mismos factores de riesgo que las comunidades restantes.

The aim of this study was to determine the prevalence of intestinal parasites and their epidemiological characteristics in four rural communities from Altagracia de la Montaña, Miranda State (Venezuela). A cross sectional study was conducted in February 2011 where 492 subjects were evaluated, mostly children. Informed consent was previously obtained. A clinical and epidemiological survey was done. Patients voluntarily brought a fresh stool sample for analysis with direct smear, Kato and agar culture; blood was extracted for eosinophil count. 60% of the evaluated people had at least one parasite transmitted by water or food contaminated by human or animal feces. The high prevalence of protozoa, specially Blastocystis sp., among those who live under poor living conditions such as inadequate feces disposal and low quality of drinking water, shows the persistence of intestinal parasites as a public health problem; nevertheless, indirect influence of ivermectin treatment every six months and health education with an ethnographic orientation given by the Onchocerciasis Elimination Programme in Bucarito, one of the evaluated communities, had an unexpected outcome not only diminishing the prevalence of helminthes but also the prevalence of intestinal protozoa, being this community under the same risk factors as the rest of the evaluated communities.

An intestinal parasitological survey among the Jehai Orang Aslis (aborigines) of the Temenggor forest, Perak state, Malaysia

Background: In Malaysia, the most common soiltransmitted helminth infections are A. lumbricoides, T. trichiura and hookworms. However, as there have been no extensive surveys on these infections, it is difficult to estimate with certainty the current overall incidence of infection with soil-transmitted helminths (STHs) among the Malaysian population including the Orang Aslis. Materials and Methods: A study was conducted to determine the infection rate of soil-transmitted helminths and intestinal protozoa among the Jehai Orang Aslis (Aborigines). The study was conducted between December 2005 and August 2006, in four Jehai villages of Perak State, Malaysia. A total of 175 stool samples was collected and personal identification such as name, age, household identification, and date of collection were recorded on the spot during collection. Faecal smears were stained with Trichrome for protozoa cysts and trophozoites and the modified Ziehl-Neelsen acid-fast method for the oocyst of Cryptosporidium and Isospora. Wet mounts with tincture of iodine of both stool samples (10% formalin and PVA) were also examined to detect cysts, ova and larva of intestinal helminths. Results: The prevalence rates of Trichuris trichiura, Ascaris lumbricoides and hookworm among the Jehai were 70.8%, 24.0%, and 10.9% respectively. The prevalence of Entamoeba coli, Entamoeba histolytica, Giardia intestinalis, Blastocystis hominis, and microsporidium was 40.6%, 33.7%, 25.7%, 91.4%, and 27.4% respectively. The difference in prevalence rates among the different age-groups and sex were found not significant. Children aged 0-9 years old had the highest prevalence rate of intestinal parasites and only 2 (1.1%) were free of any intestinal parasites. Conclusion: Intestinal parasitic infections were therefore still common among these people. Children aged 0-9 years old were found to have the highest infection rate of all the intestinal parasites examined. Further investigations are needed to determine more specific transmission of these infections, so that an attempt to control these infections can be made.

Prevalence and risk factors for intestinal protozoa infection in elderly residents at Long Term Residency Institutions in Southeastern Brazil / Prevalência e fatores de risco para infecção por protozoários intestinais em idosos residentes nas Instituições de Longa Permanência no Sudeste do Brasil

This study determined the prevalence of intestinal protozoa in Long Term Residency Institutions for the Elderly (ILPI) in elders, nurses and food handlers, identifying the risk factors associated with the infections. Stool samples taken from the elderly (n = 293), nurses (63) and food handlers (19) were studied. Questionnaires were used with questions related to sociodemographic variables, health, behavior and health characteristics. Stool samples were examined using the techniques of Faust and Ziehl Neelsen, and the prevalence of G. duodenalis, Cryptosporidium spp., E. histolytica/dispar in the elderly was 4.0%, 1.0% and 0.3% respectively. Nurses and food handlers showed 4.8% and 5.2% positivity only for G. duodenalis, respectively. The origin of the individuals and contact with domestic animals has been associated with infection by G. duodenalis in the elderly, and contact with domestic animals was considered a risk factor for infection. The last stool examinations were related to Cryptosporidium spp.. None of the variables were associated with E. histolytica/dispar. The frequency of hand washing was significantly associated with G. duodenalis among nurses. The frequency of positive samples of G. duodenalis, Cryptosporidium spp., E. histolytica/dispar showed that ILPIs environments are conducive to this occurring due to contact between the elderly, nurses and food handlers, which are often poorly trained in hygiene procedures and food handling.

Este estudo determinou a prevalência de protozoários intestinais em Instituições de Longa Permanência para Idosos (ILPI), enfermeiros, manipuladores de alimentos identificando fatores de risco associados às infecções. Amostras de fezes de idosos (n = 293), enfermeiros (63), manipuladores de alimentos (19) foram estudadas. Foram aplicados questionários relacionados a variáveis sociodemográficas, de higiene, comportamento e características de saúde. As amostras de fezes foram examinadas pelas técnicas de Faust e Ziehl Neelsen e a prevalência de G. duodenalis, Cryptosporidium spp., E.histolytica/dispar nos idosos foi de 4,0%, 1,0% e 0,3%, respectivamente. Enfermeiros e manipuladores de alimentos apresentaram 4,8% e 5,2% de positividade apenas para G. duodenalis, respectivamente. A origem dos indivíduos, o contato com animais domésticos foram associados à infecção por G. duodenalis nos idosos, sendo que o contato com animais domésticos foi considerado um fator de risco para a infecção, o tempo do último exame coproparasitológico foi relacionado a Cryptosporidium spp.. Nenhuma das variáveis apresentaram associação com E. histolytica/dispar. A frequência da lavagem das mãos foi associada significativamente com G. duodenalis entre enfermeiros. As frequências de amostras positivas para G. duodenalis, Cryptosporidium spp., E. histolytica/dispar demonstram que ILPIs são ambientes propícios para esta ocorrência devido ao contato entre idosos, enfermeiros, manipuladores de alimentos, que muitas vezes são mal treinados em procedimentos de higiene e manipulação de alimentos.

Enteroparasitosis en niños menores de 12 años del estado Anzoátegui, Venezuela / Enteroparasites in children under 12 years old at Anzoategui State, Venezuela

Las parasitosis intestinales representan uno de los problemas más importantes de salud en Venezuela desde los puntos de vista de salud pública y desarrollo socioeconómico. El objetivo de este trabajo fue determinar la prevalencia de enteroparásitos en niños menores de 12 años de 45 comunidades del estado Anzoátegui, Venezuela. Se analizaron 5.876 muestras mediante examen directo y concentración por Kato, y se describieron las características geotopográficas por municipios, señalándose el parásito marcador de la localidad. La prevalencia general fue de 74,6%, siendo significativamente mayor en niños de 4-9 años (53,8%). Globalmente predominaron los protozoarios (82,5%), Blastocystis spp. (25,9%), Giardia intestinalis (20,6%) y Entamoeba coli (18,4%). Entre los helmintos los más comunes fueron Ascaris lumbricoides (6,9%), Trichuris trichiura (6,4%) y anquilostomideos (2,7%). Se concluyó que existe una elevada prevalencia de enteroparasitosis en la población infantil evaluada de la geografía anzoatiguense, abarcando costa, región montañosa con su piedemonte y las planicies de la mesa de Guanipa. El poliparasitismo a expensas de comensales observado en algunas comunidades, alerta sobre las precarias condiciones de salubridad que poseen, particularmente respecto a la calidad sanitaria del agua de consumo. Se sugiere realizar actividades de intervención educativa frecuentes para disminuir este problema de salud pública.

Intestinal parasitic diseases represent one of the most important health problems in Venezuela from both public health and socioeconomic development points of view. The main objective of this study was to determine the prevalence of enteroparasites in children under 12 years old at 45 communities of Anzoategui State, Venezuela. The study included the analysis of 5,876 samples taken by direct examination and Kato concentration, and the geotopographic characteristics were described by municipality, identifying the marker parasite per locality. The overall prevalence was 74.6%, significantly higher in children 4-9 years old (53.8%). Globally, protozoa predominated (82.5%): Blastocytis spp. (25.9%), Giardia intestinalis (20.6%) and Entamoeba coli (18.4%). Among helmints, the most common were Ascaris lumbricoides (6.9%), Trichuris trichiura (6.4%), and hookworms (2.7%). It was concluded that there is a high prevalence of enteroparasites in the child population of the Anzoategui State geography evaluated, which includes a mountainous region with its piedmont and the plane regions of the Guanipa mesa. The polyparasitism at the expense of commensals observed in some communities reflects their precarious sanitary conditions, especially regarding the quality of the drinking water available, suggesting that health education activities be carried out frequently to decrease this public health problem.

Intestinal Parasitic Infection in the Suruí Indians, Brazilian Amazon / Parasitosis intestinal en los Indios Suruí, Amazonia Brasilera / Infecção por parasitoses intestinais entre os Indios Suruí, Amazônia Brasileira

This study reports the results of a cross-sectional survey carried out in 2005 to investigate the epidemiology of intestinal parasitism among the Suruí Indians, Brazilian Amazon. A total of 519 stool samples were examined by zinc-sulphate-flotation and formol-ether-sedimentation. Entamoeba histolytica/E. dispar-positive samples were further tested by ELISA. Thirty-six percent of the subjects were positive for one more helminth species; 70.7% harbored at least one protozoan species. The most frequent helminth was Hymenolepis nana (29.5%). Nematodes were rare (hookworm= 3.3%; Strongyloides stercoralis= 0.2%). Capillaria sp. was identified in 5.2% of the samples and one case of parasitism by Dipylidium caninum was detected. Prevalence of Giardia duodenalis and E. histolytica/E. dispar was 16.2% and 12.3%, respectively. Based on ELISA, the prevalence of E. histolytica infection was 3.2%. The overall prevalence of intestinal nematode infections depicted in this study was surprisingly low compared to what is often reported for other indigenous populations in the Brazilian Amazon. It is argued that the prevalence of helminths in the Suruí are associated with anthelminthic mass treatment schemes undertaken by the Indian health service, in the absence of other measures. The authors propose that a special program aimed at controlling intestinal parasitism in indigenous communities should step beyond the top-down distribution of medication, but rather be designed in collaboration with the target population, encompassing education, better housing, alternative sewage disposal systems and safe water supply to all villagers.

Se reportan los resultados de un estudio transversal llevado a cabo en 2005 sobre la epidemiología del parasitismo intestinal en indios Suruí de la amazonia brasilera. Un total de 519 muestras de heces fueron examinadas por flotación en sulfato de zinc y sedimentación en etil-éter. Muestras positivas para Entamoeba histolytica/E. dispar fueron testeadas por ELISA. Una o más especies de helmintos estuvieron presentes en 36% de los sujetos y 70,7% presentaron al menos una especie de protozoario. El helminto más frecuente fue Hymenolepis nana (29,5%). Los nematodos fueron escasos (anquilostomo= 3,3%; Strongyloides stercoralis= 0.2%). Se identificó Capillaria sp. en 5,2% de las muestras y se detectó un caso de parasitismo por Dipylidium caninum. Las prevalencias de Giardia duodenalis y E. histolytica/E. dispar fueron 16,2% y 12,3%, respectivamente. Según ELISA la prevalencia de infección por E. histolytica fue 3,2%. La prevalencia de infección por nematodos fue sorpresivamente baja en comparación con reportes frecuentes en otras poblaciones indígenas de la amazonia brasilera. Se argumenta que los cambios en la prevalencia de helmintiasis en los Suruí se asocian a tratamientos masivos con antihelmínticos llevados a cabo por el servicio de salud de indígenas, en ausencia de otras medidas. Se propone que un programa especial orientado a controlar el parasitismo intestinal en poblaciones indígenas debe desligarse de la distribución de medicación, sino ser diseñado en colaboración con los habitantes locales, abarcando educación, mejores viviendas y sistemas de drenaje y disposición de residuos, y suministro de agua segura a todos los pobladores.

Este trabalho apresenta os resultados de um estudo seccional conduzido em 2005 que visou investigar o perfil epidemiológico das parasitoses intestinais entre os índios Suruí, localizados em Rondôna, Amazônia brasileira. Um total de 519 amostras fecais foi examinado pelas técnicas de flutuação com sulfato de zinco e sedimentação com formol-éter. Amostras positivas para Entamoeba histolytica/E. díspar foram posteriormente testadas pelo método ELISA. Trinta e seis por cento dos indivíduos encontravam-se positivos para pelo menos uma espécie de helminto; 70,7% abrigavam pelo menos uma espécie de protozoário. O helminto mais freqüente foi Hymenolepis nana (29,5%). Nematódeos foram raros (ancilostomídeos= 3,3%; Strongyloides stercoralis= 0,2%). Capillaria sp. foi identificado em 5,2% das amostras e um caso de parasitismo por Dipylidium caninum foi observado. As prevalências de Giardia duodenalis e E. histolytica/E. dispar foram de 16,2% e 12,3%, respectivamente. Baseada no teste ELISA, a prevalência de infecção por E. histolytica foi de 3,2%. A prevalência total de infecção intestinal por nematódeos demonstrada neste estudo foi surpreendentemente baixa se comparada ao que tem sido geralmente reportado para outras populações indígenas da Amazônia brasileira. Argumenta-se que a baixa prevalência de helmintos entre os Suruí está em larga medida associada a esquemas de tratamento em massa com anti-helmínticos dispensados pelo serviço de saúde indígena. Os autores propõem que um programa especial destinado ao controle de parasitoses intestinais em comunidades indígenas deve ir além da distribuição de medicamentos. Preferencialmente, deve ser planejado em colaboração com a população alvo, considerando aspectos educacionais e visando a melhoria nas moradias e no sistema de esgoto e de fornecimento de água.

Giardiasis Among Orang Asli Children at Pos Lenjang, Pahang / Jurnal Sains Kesihatan Malaysia

Giardia intestinalis is a cosmopolitan parasite and the infection is widely distributed worldwide especially in the developing countries with poor sanitation and lack of potable water. Seventy one Orang Asli children from Pos Lenjang, Pahang participated in this study and stool specimens were collected and examined for G. intestinalis using three diagnostic techniques ie; Direct fecal smear, Formalin-ether concentration and Trichrome staining. The prevalence of G. intestinalis infection among the Orang Asli children in Pos Lenjang, Pahang was as high as 43.7%. According to gender, the prevalence was almost similar between the female and male children with 45.0% and 41.9%, respectively. The infection was more prevalent in school going children (48.6%) as compared to the pre-school children (38.2%).

Entamoeba histolytica Infection Among Aborigines at Pos Lenjang, Pahang / Jurnal Sains Kesihatan Malaysia

Entamoeba histolytica infection is widespread worldwide and higher prevalence is usually seen among the indigenous under priviledged people living in the tropics and subtropics. Seventy one Orang Asli children from Pos Lenjang, Pahang participated in this study and were grouped according to age and gender. Faecal samples were collected and examined for the presence of Entamoeba histolytica using 3 different diagnostic techniques namely the direct faecal smear, formalin ether concentration and trichrome staining.The prevalence of Entamoeba histolytica infection among the Orang Asli children at Pos Lenjang, Pahang was high at 22.5%. According to gender, female children showed higher prevalence (32.5%) compared to male at only 9.7%. Infection was also apparently higher among the school going children at 32.4% compared to preschool children (11.8%). The high prevalence of Entamoeba histolytica infection amongst the Orang Asli children at Pos Lenjang is related to several factors including low socioeconomic status, lack of basic amenities, culture, and poor knowledge on healthy life practice.

Perfil de parásitos y comensales entéricos de comunidades del cantón de Barva, Heredia, Costa Rica / Profile diners enteric parasites and communities in the canton of Barva, Heredia, Costa Rica

Se analizó la frecuencia de los protozoarios y helmintos observados en las muestras fecales de los pacientes que consultaron el laboratorio del Área de Salud de Barva, Coopesiba R.L., durante enero a noviembre del 2004. La presencia de organismos parásitos y comensales fue evidenciada en las muestras procedentes de todas las comunidades, mostrando una prevalencia global del 41.2 por ciento. Las comunidades de San Roque y Barva Distrito Central fueron las que presentaron, en los análisis efectuados, las prevalencias más alta, 45,4 por ciento, y más baja, 35,0 por ciento, respectivamente. Los organismos más frecuentes fueron Blastocystis hominis, con una prevalencia global del 27,4 por ciento, Endolimaz nana, 16,5 por ciento, y Entamoeba coli, 7,4 por ciento. Los únicos helmintos observados fueron Trichuris trichiura, 0,03 por ciento, e Hymenolepis nana, 0,1 por ciento. La distribución de los parásitos en las localidades del Cantón de Barva no fue homogénea. Los resultados mostraron prevalencias de organismos relativamente bajas pero sugieren la ocurrencia de condiciones permisivas para la transmisión de enteropatógenos que hacen su diseminación por fecalismo, lo cual conlleva la necesidad de insistir en medidas preventivas.

The frequency of protozoa and helminths observed in the fecal samples of the patients who consulted in the laboratory of the Barva Health Area (also known as Coopesiba, R.L.), during the months of January to November of 2004 was analyzed. The presence of parasitic as well as commensal organisms was evidenced in the samples coming from all the differentcommunities, showing a global prevalence of 41.2%. Thecommunities of San Roque as well as the Central District of Barva were the ones which showed, in the analysescarried out, the highest (45.4%) and the lowest (35.0%) prevalences, respectively. The most frequent organisms were Blastocystis hominis with a global prevalence of 27.4%, Endolimax nana (16.5%) and Entamoeba coli (7.4%). The only helminthic organisms observed wereTrichuris trichiura (0.03%) and Hymenolepis nana (0.1%). The parasite distribution in the communities of Barvawas not homogeneous. The results showed relatively low prevalences of the organisms but suggest the existenceof permissive conditions for transmission of enteric pathogens disseminated via the fecal route all of which emphasizes the need to stress preventive measures.