Parasitic infections of the intestines

The prevalence of intestinal parasites, undernutrition and their associated risk factors among school-age children in Sekota Town, Northeast Ethiopia: A community-based cross-sectional study

Background and Aims

In developing countries, intestinal parasitic infections and malnutrition are among the most serious health issues affecting school-aged children. They have synergetic consequences. This study aimed to determine the prevalence of intestinal parasites, undernutrition, and their associated risk factors among school-age children.

Methods

A community-based cross-sectional study was conducted from April to June 2021 among school-age children in Sekota Town, Northeast Ethiopia. Households were selected using a systematic random sampling technique. Risk factor variables were collected using pretested questionnaires. Stool samples were collected from study participants and examined using a wet mount, formol-ether concentration, and modified acid-fast techniques. The height and weight of children were also measured using a meter and a standard calibrated balance, respectively. Data were analyzed using SPSS version 26.0 statistical software.

Results

The overall prevalence of intestinal parasites among school-age children was 44.3% (178/402). About seven species of intestinal parasites were identified. The predominant parasite identified was E. histolytica/dispar (11.2%), followed by H. nana (9.2%) and G. lamblia (6.7%). The well as a source of drinking water (adjusted odds ratio [AOR] = 7.93; 95% confidence interval [CI]: 4.38-14.36), habit of open-field defecation (AOR = 7.02; 95% CI: 13.05-12.06), and being undernourished (AOR = 5.67; 95% CI: 2.98-10.79) were independent predictors of intestinal parasitic infections. On the other hand, the overall prevalence of undernutrition was 46.3%. Undernutrition was significantly more likely in children with a dietary diversity score (DDS) of 3 (AOR = 3.73, 95% CI: 2.37-5.88), meal frequency of no more than three times per day (AOR = 2.00, 95% CI: 1.71-2.98), intestinal parasite infection (AOR = 5.25, 95% CI: 3.24-8.52), and no access to school-based feeding (AOR = 3.52, 95% CI: 2.17-7.96).

Conclusion

The prevalence of intestinal parasitic infections and undernutrition was high among school-age children in Sekota Town. The results imply the need for strengthening integrated strategies for the reduction of intestinal parasitic infections and undernutrition.

Assessment of Prevalence and Risk Factors for Intestinal Parasitosis, Malnutrition, and Anemia among School Children in Ghindae Area, Eritrea

Background

Research studies on determination of risk factors for intestinal parasitic infections and related malnutrition and anemia in various tropical areas are necessary for appropriate preventive resource allocation and cost effective control. This study is aimed at evaluating the prevalence and risk factors of intestinal parasitosis, malnutrition, and anemia amongst elementary and junior school students in Ghindae area, Eritrea.

Method

A cross-sectional study was conducted in 6 schools around Ghindae from February to April 2018. 460 children were selected randomly for analysis and consent was taken from guardians. The pertinent sociodemographic data was collected using a pretested questionnaire, and anthropometric measurements were carried out to determine the proportion of students with malnutrition, stunting, and thinness. Fecal samples were examined by formal-ether concentration technique, and blood specimen was collected and analyzed for the assessment of hemoglobin using Hemocue analyzers. The association between predictors and outcome variables were measured with a stepwise logistic regression model.

Result

The overall prevalence of intestinal parasitosis was 45.3%. Protozoan infections (38.2%) were more prevalent than soil-transmitted helminthic infections (10.4%). The presence of different intestinal parasitic infections had statistically significant association with the residence area, hand washing habits, source of drinking water, and type of latrine used. The prevalence of malnutrition was 36.9% with 18.5% stunting and 21.2% thinness. Students of rural areas had 2.03 times more odds of having malnutrition. The current prevalence of anemia was 12.4%, out of which 7.6% had mild anemia while 4.4% of them had moderate anemia and 0.4% were severely anemic.

Conclusion

The prevalence of parasitic infection among school-age children in Ghindae area was high. Unsafe drinking water sources from streams and springs were among the core problems for increased prevalence along with decreased awareness on personal hygienic and sanitation practices. Undernutrition was widely prevalent among students in Ghindae area. Height for age and BMI for age scores of all participants were found to be below the WHO growth standards. Malnutrition was in higher prevalence in rural areas outside Ghindae, which is attributed to two times higher odds than their counterparts. The magnitude of anemia found in this study is considered a mild public health problem.

Intestinal parasitic infections among public and private schoolchildren of Kathmandu, Nepal: prevalence and associated risk factors

Objective

Intestinal parasitic infections (IPIs) are a major cause of morbidity among children in developing countries. Investigation about the etiological agents and socio-ecological pattern of the infection would help to design better preventive strategy. The previous studies reported high prevalence of IPIs among schoolchildren of Nepal. Though these data may be essential for the policymakers and researchers, in Kathmandu, the capital of Nepal it remains unexplored whether the types of school and socioeconomic status affect the IPIs or not. The present study is an extension of previous works to investigate causative agents and associated risk factors. We examined 508 stool samples of schoolchildren from two schools by formal-ether concentration technique and analyzed the data based on school types.

Results

The overall IPIs rate was 19.9% (n = 101) with the dominance of protozoans (78.4%) over helminths (21.6%). Giardia duodenalis (32.7%) and Ascaris lumbricoides (21.8%) were the most commonly detected protozoan and helminth species respectively. Prevalence of IPIs was higher among children from public school (26.1%) than private school (12.1%). Higher infection rates were found among farmer’s children (29.0%) and Dalit children (36.2%). These findings reveal the different prevalence of IPIs among public and private schoolchildren and suggest the need of effective preventive measures.

Improvement in the detection of enteric protozoa from clinical stool samples using the automated urine sediment analyzer sediMAX® 2 compared to sediMAX® 1

Detection of intestinal parasites from fecal samples is routinely performed by direct wet mount examination. This method requires skilled personnel, and it is time consuming. The aim of this work is to demonstrate the usefulness of the newer automated urinary sediment analyser sediMAX 2 for a fast detection of intestinal protozoa in stool samples. A total of 700 consecutively preserved samples consisting of 70 positives and 630 negatives were analyzed. SediMAX 2 takes digital images of each sediment sample, and analysis was conducted using a dilution of stool specimens, allowing determination of typical morphology. Compared to manual microscopy, sediMAX 2 showed sensitivity and specificity of 100 % in the detection of intestinal parasites, as also recently demonstrated for sediMAX 1. However, all clinically important human protozoa were detected using only 15 images for each specimen, compared to 30 images required in sediMAX 1 analysis. Moreover, changing manually the focus, it is possible to carry out a discrimination between morphologically identical Entamoeba complex members, including the pathogenic E. histolytica and the non-pathogenic E. dispar, E. moshkovskii and E. Bangladeshi, from the non-pathogenic Entamoeba coli based on the number of nuclei present in the cells. This study presents sediMAX 2 as an automatic aid to traditional microscopy.

Molecular testing for clinical diagnosis and epidemiological investigations of intestinal parasitic infections

Over the past few decades, nucleic acid-based methods have been developed for the diagnosis of intestinal parasitic infections. Advantages of nucleic acid-based methods are numerous; typically, these include increased sensitivity and specificity and simpler standardization of diagnostic procedures. DNA samples can also be stored and used for genetic characterization and molecular typing, providing a valuable tool for surveys and surveillance studies. A variety of technologies have been applied, and some specific and general pitfalls and limitations have been identified. This review provides an overview of the multitude of methods that have been reported for the detection of intestinal parasites and offers some guidance in applying these methods in the clinical laboratory and in epidemiological studies.

Detection of intestinal parasites by use of the cuvette-based automated microscopy analyser sediMAX(®)

Microscopy is the reference method for intestinal parasite identification. The cuvette-based automated microscopy analyser, sediMAX 1, provides 15 digital images of each sediment sample. In this study, we have evaluated this fully automated instrument for detection of enteric parasites, helminths and protozoa. A total of 700 consecutively preserved samples consisting of 60 positive samples (50 protozoa, ten helminths) and 640 negative samples were analysed. Operators were blinded to each others' results. Samples were randomized and were tested both by manual microscopy and sediMAX 1 for parasite recognition. The sediMAX 1 analysis was conducted using a dilution of faecal samples, allowing determination of morphology. The data obtained using sediMAX 1 showed a specificity of 100% and a sensitivity of 100%. Some species of helminths, such as Enterobius vermicularis, Strongyloides stercolaris, the Ancylostoma duodenale/Necator americanus complex, and schistosomes were not considered in this work, because they are rare in stool specimens, are not easily detectable with microscopy analysis, and require specific recovery techniques. This study demonstrated for the first time that sediMAX 1 can be an aid in enteric parasite identification.

Antibodies fused to innate immune molecules reduce initiation of Cryptosporidium parvum infection in mice

At present no completely effective treatments are available for Cryptosporidium parvum infections in humans and livestock. Based on previous data showing the neutralizing potential of a panel of monoclonal antibodies developed against C. parvum, and based on the fact that innate immune peptides and enzymes have anticryptosporidial activity, we engineered several of these antibodies into antibody-biocide fusion proteins. We hypothesized that the combination of high-affinity antibody targeting with innate immune molecule-mediated killing would result in a highly effective new antiprotozoal agent. To test this hypothesis, we expressed antibody-biocide fusion proteins in a mammalian cell culture system and used the resulting products for in vitro and in vivo efficacy experiments. Antibody-biocide fusion proteins efficiently bound to, and destroyed, C. parvum sporozoites in vitro through a membrane-disruptive mechanism. When antibody-biocide fusion proteins were administered orally to neonatal mice in a prophylactic model of cryptosporidiosis, the induction of infection was reduced by as much as 81% in the mucosal epithelium of the gut, as determined on the basis of histopathological scoring of infectious stages. Several versions of antibody fusion proteins that differed in antigen specificity and in the biocide used had strong inhibitory effects on the initiation of infection. The results lay the groundwork for the development of a new class of antimicrobials effective against Cryptosporidium.

The molecular epidemiology of Cryptosporidium and Giardia infections in coyotes from Alberta, Canada, and observations on some cohabiting parasites

Coyotes from southern Alberta and Saskatchewan, Canada, were examined for the presence of Giardia and Cryptosporidium and cohabiting helminths. Toxascaris was present in over 90% of the 70 animals examined, and Taenia sp. in 6.5-25% of the two groups of animals studied. Giardia (12.5-21.7%) and Cryptosporidium (0-17.4%) were also common and molecular characterisation revealed both zoonotic and host-adapted genotypes of Giardia, whereas the Cryptosporidium proved to be a variant of the canine species C. canis. The seasonal variation observed in the occurrence of Cryptosporidium may be related to stress-induced shedding of the parasite.