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PLoS Neglected Tropical Diseases Apr 2011Sensitive diagnostic tools are required for an accurate assessment of prevalence and intensity of helminth infections in areas undergoing regular deworming, and for...
BACKGROUND
Sensitive diagnostic tools are required for an accurate assessment of prevalence and intensity of helminth infections in areas undergoing regular deworming, and for monitoring anthelmintic drug efficacy. We compared the diagnostic accuracy of the Kato-Katz and FLOTAC techniques in the frame of a drug efficacy trial.
METHODOLOGY/PRINCIPAL FINDINGS
Stool samples from 343 Zanzibari children were subjected to duplicate Kato-Katz thick smears and the FLOTAC basic technique in a baseline screening in early 2009. The FLOTAC showed a higher sensitivity than the Kato-Katz method for the diagnosis of Trichuris trichiura (95% vs. 88%, p = 0.012) and Ascaris lumbricoides (88% vs. 68%, p = 0.098), but a lower sensitivity for hookworm diagnosis (54% vs. 81%, p = 0.006). Considering the combined results from both methods as 'gold' standard, the prevalences of T. trichiura, hookworm and A. lumbricoides were 71% (95% confidence interval (CI): 66-75%), 22% (95% CI: 17-26%) and 12% (95% CI: 8-15%), respectively. At follow-up, 3-5 weeks after 174 among the 269 re-examined children were administered anthelmintic drugs, we observed cure rates (CRs) against A. lumbricoides, hookworm and T. trichiura of 91% (95% CI: 80-100%), 61% (95% CI: 48-75%) and 41% (95% CI: 34-49%), respectively, when using the Kato-Katz method. FLOTAC revealed lower CRs against A. lumbricoides (83%, 95% CI: 67-98%) and T. trichiura (36%, 95% CI: 29-43%), but a higher CR against hookworm (69%, 95% CI: 57-82%). These differences, however, lacked statistical significance. Considerable differences were observed in the geometric mean fecal egg counts between the two methods with lower egg reduction rates (ERRs) determined by FLOTAC.
CONCLUSION/SIGNIFICANCE
Our results suggest that the FLOTAC technique, following further optimization, might become a viable alternative to the Kato-Katz method for anthelmintic drug efficacy studies and for monitoring and evaluation of deworming programs. The lower CRs and ERRs determined by FLOTAC warrant consideration and could strategically impact future helminth control programs.
Topics: Adolescent; Ancylostomatoidea; Animals; Anthelmintics; Ascariasis; Ascaris lumbricoides; Child; Female; Hookworm Infections; Humans; Male; Parasitology; Tanzania; Treatment Outcome; Trichuriasis; Trichuris; Young Adult
PubMed: 21532740
DOI: 10.1371/journal.pntd.0001036 -
Clinical and Experimental Immunology Aug 2009The 13q33-34 region harbours a susceptibility locus to Ascaris lumbricoides, although the underlying genes are unknown. Immunoglobulin (Ig)E and IgG confer protective...
Association between total immunoglobulin E and antibody responses to naturally acquired Ascaris lumbricoides infection and polymorphisms of immune system-related LIG4, TNFSF13B and IRS2 genes.
The 13q33-34 region harbours a susceptibility locus to Ascaris lumbricoides, although the underlying genes are unknown. Immunoglobulin (Ig)E and IgG confer protective immunity and here we sought to investigate in an endemic population whether LIG4, TNFSF13B and IRS2 genes influence IgE and IgG levels against Ascaris and the ABA-1 allergen as a putative resistance marker. Mite-allergic asthmatic patients were analysed for potential relationships between Ascaris predisposition and allergy. One thousand and sixty-four subjects from Cartagena, Colombia, were included. Single nucleotide polymorphisms (SNPs) were genotyped using TaqMan assays. Antibody levels were measured by enzyme-linked immunosorbent assay. Linear and logistic regressions were used to model effects of genotypes on antibody levels. The GG genotype of LIG4 (rs1805388) was associated with higher IgE levels to Ascaris compared with other genotypes. TNFSF13B (rs10508198) was associated positively with IgG levels against Ascaris extract and IgE levels against ABA-1. In asthmatics, IRS2 (rs2289046) was associated with high total IgE levels. Associations held up after correction by population stratification using a set of 52 ancestry markers, age, sex and disease status. There was no association with asthma or mite sensitization. In a tropical population, LIG4 and TNFSF13B polymorphisms are associated with specific IgE and IgG to Ascaris, supporting previous linkage studies implicating the 13q33 region. Our results suggest that genes protecting against parasite infections can be different to those predisposing to asthma and atopy.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Animals; Antibodies, Helminth; Ascariasis; Ascaris lumbricoides; Asthma; B-Cell Activating Factor; Case-Control Studies; Child; DNA Ligase ATP; DNA Ligases; Female; Genetic Predisposition to Disease; Genotype; Humans; Immunoglobulin E; Insulin Receptor Substrate Proteins; Linear Models; Male; Middle Aged; Polymorphism, Genetic; Young Adult
PubMed: 19604268
DOI: 10.1111/j.1365-2249.2009.03948.x -
Medicina 2014A systematic review of surveys performed between 1980 and 2011 (published in MEDLINE/Pubmed and/or LILACS indexed journals, available in the baseline data from a Mass... (Review)
Review
A systematic review of surveys performed between 1980 and 2011 (published in MEDLINE/Pubmed and/or LILACS indexed journals, available in the baseline data from a Mass Deworming National Program (MDNP, 2005) was used to identify the prevalence, distribution and detection of risk areas for soil transmitted helminth infections (STH) in Argentina. We found 310 publications in the database using the pre-defined key-words (medical subject headings) for research purposes. Only 24 articles with 26 surveillance sites in 8 provinces and a total of 5495 surveyed individuals fulfilled the inclusion criteria. Frequency rates for STH had a wide range: Ascaris lumbricoides: 0-67%, hookworms: 0-90%, Trichuris trichiura: 0-24.6 and Strongyloides stercoralis: 0-83%. The estimated combined incidence varied from 0.8% to 88.6%. Baseline surveys from the MDNP reporting on 1943 children from 12 provinces confirmed the heterogeneity, with combined STH frequency rates ranging from 0 to 42.7%. Surveys included in this review showed that the distribution of STH in Argentina is not homogeneous, with areas of high incidence (> 20%) in the northeastern and northwestern provinces where mass deworming activities would be highly beneficial. In several surveys, the high overall incidence was mostly due to hookworms and S. stercoralis, a situation to be considered when selecting diagnostic and therapeutic control strategies. The scarcity or absence of data from various provinces and the availability of less than 8000 surveyed individuals should be considered.
Topics: Adolescent; Adult; Animals; Argentina; Ascariasis; Ascaris lumbricoides; Child; Child, Preschool; Helminthiasis; Humans; Prevalence; Soil; Strongyloides stercoralis; Strongyloidiasis; Trichuriasis; Trichuris
PubMed: 24561837
DOI: No ID Found -
Przeglad Epidemiologiczny 2018Co-infections of HIV and other pathogens constitute an important clinical and epidemiological problem. Many studies have played attention to opportunistic co-infections... (Review)
Review
Selected aspects of helminth infections Schistosoma sp., Ascaris lumbricoides, Strongyloides stercoralis in individuals diagnosed with human immunodeficiency virus (HIV) infection.
Co-infections of HIV and other pathogens constitute an important clinical and epidemiological problem. Many studies have played attention to opportunistic co-infections due to the fact that they are used as an indicator for development of AIDS and are present on the all continents. However, in HIV-infected patients helminth infections, which are not aetiologic agents of opportunistic infections, are becoming more and more important. Prevalence of helminth infection depends on parasite species, environmental and socio-economic factors, therefore the results of published research mainly refer to populations of patients in developing countries and endemic regions. In many cases, pathogenetic mechanisms of these co-infections are not fully recognized, and the obtained results are ambiguous. Thus we performed literature review concerning the course and implications of co-infections with three selected helminth species, of different tissue/organ tropism (Ascaris lumbricoides, Strongyloides stercoralis, Schistosoma sp.), in patients with HIV infection.
Topics: Animals; Ascariasis; Ascaris lumbricoides; Coinfection; HIV Infections; Helminthiasis; Humans; Strongyloides stercoralis; Strongyloidiasis
PubMed: 30394059
DOI: 10.32394/pe.72.3.11 -
Infectious Diseases of Poverty Feb 2017School-based deworming is widely implemented in various countries to reduce the burden of soil-transmitted helminths (STHs), however, the frequency of drug... (Randomized Controlled Trial)
Randomized Controlled Trial
Impact of single annual treatment and four-monthly treatment for hookworm and Ascaris lumbricoides, and factors associated with residual infection among Kenyan school children.
BACKGROUND
School-based deworming is widely implemented in various countries to reduce the burden of soil-transmitted helminths (STHs), however, the frequency of drug administration varies in different settings. In this study, we compared the impact of a single annual treatment and 4-monthly treatment over a follow-up among Kenyan school children, and investigated the factors associated with residual infection.
METHODS
We performed a secondary analysis of data from a randomized trial investigating whether deworming for STHs alters risk of acquiring malaria. Children received either a single treatment or 4-monthly albendazole treatments were followed longitudinally from February 2014 to October 2014. The relative impact of treatment and factors associated with residual infections were investigated using mixed-effects regression models. Predisposition to infection was assessed based on Spearman's rank and Kendall's Tau correlation coefficients.
RESULTS
In the 4-monthly treatment group, the proportion of children infected with hookworm decreased from 59.9 to 5.7%, while Ascaris lumbricoides infections dropped from 55.7 to 6.2%. In the single treatment group, hookworm infections decreased over the same time period from 58.7 to 18.3% (12.6% absolute difference in reduction, 95% CI: 8.9-16.3%), and A. lumbricoides from 56.7 to 23.3% (17.1% absolute difference in reduction, 95% CI: 13.1-21.1%). There was strong evidence for predisposition to both STH types. Residual hookworm infection among children on 4-monthly treatment were associated with male sex and baseline nutritional status, whereas A. lumbricoides infection was associated with individual and school-level infection at baseline, latrine cleanliness at schools.
CONCLUSIONS
This study found that 4-monthly treatment w more effective than single annual treatment. Repeated treatments led to dramatic reductions in the intensities of STHs, but did not completely clear infections among school children in Kenya, a presumed reflection of reinfection in a setting where there is ongoing transmission.
Topics: Adolescent; Albendazole; Ancylostomatoidea; Animals; Anthelmintics; Ascariasis; Ascaris lumbricoides; Child; Child, Preschool; Female; Hookworm Infections; Humans; Kenya; Longitudinal Studies; Male; Schools; Students; Treatment Outcome
PubMed: 28179024
DOI: 10.1186/s40249-017-0244-z -
The American Journal of Tropical... May 2016Water, sanitation, and hygiene (WaSH) technologies and behaviors can prevent infection by soil-transmitted helminth species independently, but may also interact in...
Water, sanitation, and hygiene (WaSH) technologies and behaviors can prevent infection by soil-transmitted helminth species independently, but may also interact in complex ways. However, these interactions are poorly understood. The purpose of this study was to characterize how school and home WaSH exposures were associated with Ascaris lumbricoides infection and to identify relevant interactions between separate WaSH technologies and behaviors. A study was conducted among 4,404 children attending 51 primary schools in western Kenya. We used multivariable mixed effects logistic regression to characterize how various WaSH exposures were associated with A. lumbricoides infection after annual school-based deworming. Few WaSH behaviors and technologies were independently associated with A. lumbricoides infection. However, by considering relevant interdependencies between variables, important associations were elucidated. The association between handwashing and A. lumbricoides depended largely upon the pupils' access to an improved water source. Among pupils who had access to improved water sources, A. lumbricoides prevalence was lower for those who handwashed both at school and home compared with neither place (odds ratio: 0.38, 95% confidence interval: 0.18-0.83; P = 0.01). This study contributes to a further understanding of the impact of WaSH on A. lumbricoides infection and shows the importance of accounting for interactions between WaSH technologies and behaviors.
Topics: Animals; Anthelmintics; Ascariasis; Ascaris lumbricoides; Child; Family Characteristics; Female; Humans; Hygiene; Kenya; Male; Sanitation; Schools; Water Supply
PubMed: 26903608
DOI: 10.4269/ajtmh.15-0362 -
Transactions of the Royal Society of... Jan 2017The morbidity due to Ascaris lumbricoides and Trichuris trichiura is caused by infections of moderate and heavy intensity while hookworm infections of all intensities... (Meta-Analysis)
Meta-Analysis Review
The morbidity due to Ascaris lumbricoides and Trichuris trichiura is caused by infections of moderate and heavy intensity while hookworm infections of all intensities are recognized to cause morbidity. This study aims to evaluate the effect of repeated rounds of preventive chemotherapy on the proportion of soil-transmitted helminth (STH) infections causing morbidity. We identified studies from 17 countries, reporting changes in the proportion of STH infection causing morbidity between baseline and follow-up. In the studies identified, the average proportion of individuals with STH infections of moderate and heavy intensity was of 14% at baseline and was on average reduced to 2% by the intervention (i.e., 85% reduction). There was an average reduction of 73% after the first year of treatment, which reached almost 80% after 5 years and over 95% in 10 years of deworming interventions. The reduction in hookworm prevalence was 57% after 12 months reaching 78% after 5 years. We consider the results presented in this study especially useful for decision makers as it demonstrates the effectiveness of preventive chemotherapy in reducing STH prevalence and morbidity. We encourage the implementation of deworming programs to achieve the goal, set by WHO for 2020, to eliminate STH morbidity in children.
Topics: Ancylostomatoidea; Animals; Ascariasis; Ascaris lumbricoides; Chemoprevention; Child; Female; Global Health; Helminthiasis; Hookworm Infections; Humans; Male; Soil; Trichuriasis; Trichuris
PubMed: 28340144
DOI: 10.1093/trstmh/trx011 -
Respiratory Research Aug 2010The elucidation of factors that trigger the development of transient wheezing in early childhood may be an important step toward understanding the pathogenesis of asthma... (Comparative Study)
Comparative Study
The presence of serum anti-Ascaris lumbricoides IgE antibodies and of Trichuris trichiura infection are risk factors for wheezing and/or atopy in preschool-aged Brazilian children.
BACKGROUND
The elucidation of factors that trigger the development of transient wheezing in early childhood may be an important step toward understanding the pathogenesis of asthma and other allergic diseases later in life. Transient wheezing has been mainly attributed to viral infections, although sensitisation to aeroallergens and food allergens may occur at an early age. In developing countries, intestinal helminthic infections have also been associated with allergy or atopy-related disorders.
OBJECTIVE
The aim of this study was to explore the association of Trichuris trichiura and Ascaris lumbricoides infections with wheezing and atopy in early childhood.
STUDY DESIGN
A cross-sectional study using a Portuguese-language ISAAC phase I questionnaire, adapted for preschool-aged children, nested in a cohort study of childhood diarrhoea, was conducted on 682 children. Two faecal samples per child were examined for the presence of intestinal helminthic infection. IgE antibodies against three allergenic preparations (Dermatophagoides pteronyssinus, Blomia tropicalis and common child food), as well as against A. lumbricoides antigens, were measured in a sub-sample of these children, whose parents allowed the procedure. Atopy was defined by the presence of levels of serum IgE antibodies ≥0.35 kU/L against at least one of the three tested allergenic preparations.
RESULTS
Active T. trichiura infection but not A. lumbricoides infection was positively associated with wheezing in the total studied children population [adjusted OR = 2.60; CI = 1.54;4.38] and in the atopic children sub-population [adjusted OR = 3.07; CI = 1.00;9.43]. The association with atopy was also positive and statistically significant only in the brute analysis [OR = 2.13; CI = 1.03;4.40]. Anti-A. lumbricoides IgE antibodies, but not current A. lumbricoides infection, were positively associated with wheezing in atopic children [adjusted OR = 2.01; CI = 1.00;4.50] and in non-atopic children [adjusted OR = 3.07; CI = 1.13;8.35] and it was also associated with atopy [adjusted OR = 7.29; CI = 3.90; 13.4]. On the other hands, reports of wheezing were not significantly associated with atopy.
CONCLUSIONS
These data corroborate previous studies showing that wheezing is predominantly associated with infection in early childhood and shows that anti-A. lumbricoides IgE antibodies, but not active Ascaris infections, are associated with wheezing and atopy. Additionally, the data demonstrate that T. trichiura infection may play a role in the pathogenesis of atopic wheezing in early childhood.
Topics: Animals; Antibodies, Helminth; Ascariasis; Ascaris lumbricoides; Brazil; Child, Preschool; Cohort Studies; Cross-Sectional Studies; Female; Humans; Hypersensitivity, Immediate; Immunoglobulin E; Infant; Infant, Newborn; Male; Respiratory Sounds; Risk Factors; Trichuriasis; Trichuris
PubMed: 20731833
DOI: 10.1186/1465-9921-11-114 -
PLoS Neglected Tropical Diseases Aug 2021Despite several years of school-based MDA implementation, STH infections remain an important public health problem in Benin, with a country-wide prevalence of 20% in... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Despite several years of school-based MDA implementation, STH infections remain an important public health problem in Benin, with a country-wide prevalence of 20% in 2015. The DeWorm3 study is designed to assess the feasibility of using community-based MDA with albendazole to interrupt the transmission of STH, through a series of cluster-randomized trials in Benin, India and Malawi. We used the pre-treatment baseline survey data to describe and analyze the factors associated with STH infection in Comé, the study site of the DeWorm3 project in Benin. These data will improve understanding of the challenges that need to be addressed in order to eliminate STH as a public health problem in Benin.
METHODS
Between March and April 2018, the prevalence of STH (hookworm spp., Ascaris and Trichuris trichiura) was assessed by Kato-Katz in stool samples collected from 6,153 residents in the community of Comé, Benin using a stratified random sampling procedure. A standardized survey questionnaire was used to collect information from individual households concerning factors potentially associated with the presence and intensity of STH infections in pre-school (PSAC, aged 1-4), school-aged children (SAC, aged 5-14) and adults (aged 15 and above). Multilevel mixed-effects models were used to assess associations between these factors and STH infection.
RESULTS
The overall prevalence of STH infection was 5.3%; 3.2% hookworm spp., 2.1% Ascaris lumbricoides and 0.1% Trichuris. Hookworm spp. were more prevalent in adults than in SAC (4.4% versus 2.0%, respectively; p = 0.0001) and PSAC (4.4% versus 1.0%, respectively; p<0.0001), whilst Ascaris lumbricoides was more prevalent in SAC than in adults (3.0% versus 1.7%, respectively; p = 0.004). Being PSAC (adjusted Odds Ratio (aOR) = 0.2, p< 0.001; adjusted Infection Intensity Ratio (aIIR) = 0.1, p<0.001) or SAC (aOR = 0.5, p = 0.008; aIIR = 0.3, p = 0.01), being a female (aOR = 0.6, p = 0.004; aIIR = 0.3, p = 0.001), and having received deworming treatment the previous year (aOR = 0.4, p< 0.002; aIIR = 0.2, p<0.001) were associated with a lower prevalence and intensity of hookworm infection. Lower income (lowest quintile: aOR = 5.0, p<0.001, 2nd quintile aOR = 3.6, p = 0.001 and 3rd quintile aOR = 2.5, p = 0.02), being a farmer (aOR = 1.8, p = 0.02), medium population density (aOR = 2.6, p = 0.01), and open defecation (aOR = 0.5, p = 0.04) were associated with a higher prevalence of hookworm infection. Lower education-no education, primary or secondary school- (aIIR = 40.1, p = 0.01; aIIR = 30.9, p = 0.02; aIIR = 19.3, p = 0.04, respectively), farming (aIIR = 3.9, p = 0.002), natural flooring (aIIR = 0.2, p = 0.06), peri-urban settings (aIIR = 6.2, 95%CI 1.82-20.90, p = 0.003), and unimproved water source more than 30 minutes from the household (aIIR = 13.5, p = 0.02) were associated with a higher intensity of hookworm infection. Improved and unshared toilet was associated with lower intensity of hookworm infections (aIIR = 0.2, p = 0.01). SAC had a higher odds of Ascaris lumbricoides infection than adults (aOR = 2.0, p = 0.01) and females had a lower odds of infection (aOR = 0.5, p = 0.02).
CONCLUSION
Hookworm spp. are the most prevalent STH in Comé, with a persistent reservoir in adults that is not addressed by current control measures based on school MDA. Expanding MDA to target adults and PSAC is necessary to substantially impact population prevalence, particularly for hookworm.
TRIAL REGISTRATION
ClinicalTrials.gov NCT03014167.
Topics: Adolescent; Ancylostomatoidea; Animals; Ascariasis; Ascaris lumbricoides; Benin; Child; Child, Preschool; Family Characteristics; Feces; Female; Hookworm Infections; Humans; Logistic Models; Male; Prevalence; Risk Factors; Sanitation; Schools; Soil; Trichuriasis; Trichuris
PubMed: 34403424
DOI: 10.1371/journal.pntd.0009646 -
Asian Journal of Surgery Sep 2023
Review
Topics: Animals; Humans; Ascaris lumbricoides; Intestines; Intestinal Fistula; Duodenal Diseases; Aortic Diseases
PubMed: 37105813
DOI: 10.1016/j.asjsur.2023.04.045