Enteroparasitism and Risk Factors Associated with Clinical Manifestations in Children and Adults of Jalisco State in Western Mexico

Improved household flooring is associated with lower odds of enteric and parasitic infections in low- and middle-income countries: A systematic review and meta-analysis

Enteric and parasitic infections such as soil-transmitted helminths cause considerable mortality and morbidity in low- and middle-income settings. Earthen household floors are common in many of these settings and could serve as a reservoir for enteric and parasitic pathogens, which can easily be transmitted to new hosts through direct or indirect contact. We conducted a systematic review and meta-analysis to establish whether and to what extent improved household floors decrease the odds of enteric and parasitic infections among occupants compared with occupants living in households with unimproved floors. Following the PRISMA guidelines, we comprehensively searched four electronic databases for studies in low- and middle-income settings measuring household flooring as an exposure and self-reported diarrhoea or any type of enteric or intestinal-parasitic infection as an outcome. Metadata from eligible studies were extracted and transposed on to a study database before being imported into the R software platform for analysis. Study quality was assessed using an adapted version of the Newcastle-Ottawa Quality Assessment Scale. In total 110 studies were eligible for inclusion in the systematic review, of which 65 were eligible for inclusion in the meta-analysis after applying study quality cut-offs. Random-effects meta-analysis suggested that households with improved floors had 0.75 times (95CI: 0.67-0.83) the odds of infection with any type of enteric or parasitic infection compared with household with unimproved floors. Improved floors gave a pooled protective OR of 0.68 (95CI: 0.58-0.8) for helminthic infections and 0.82 OR (95CI: 0.75-0.9) for bacterial or protozoan infections. Overall study quality was poor and there is an urgent need for high-quality experimental studies investigating this relationship. Nevertheless, this study indicates that household flooring may meaningfully contribute towards a substantial portion of the burden of disease for enteric and parasitic infections in low- and middle-income settings.

Prevalence of Enterobius vermicularis among children in Iran: A comprehensive systematic review and meta-analysis

Background

Parasitic infections are among the most common diseases worldwide, and enterobiasis is a well-known type of parasitic infection in children. Given the existence of several reports on the prevalence of Enterobius vermicularis in different provinces of Iran and the heterogeneity of the reported prevalence data, this study aims to investigate the overall prevalence of Enterobius vermicularis among children in Iran through a systematic review and meta-analysis.

Methods

This systematic review and meta-analysis study involved a comprehensive search of several databases, including PubMed, ScienceDirect, SID, and Google Scholar, focusing on cross-sectional studies that examined the prevalence of Enterobius vermicularis infection in Iranian children. The identified studies were entered into the EndNote software for review. The quality of observational studies was evaluated using the STROBE checklist. The information extracted from the studies was entered into the Comprehensive Meta-analysis (CMA, Version 2) software. Heterogeneity among the studies was analyzed using the I² test, and publication bias was assessed using the Egger test and funnel plot.

Results

A total of 51 studies, with a sample size of 46,070 children, were included in the review. Using the random effects method, the overall prevalence of Enterobius vermicularis among children in Iran was determined to be 6.7% (95%CI: 5.2-8.6). The review of the factors affecting study heterogeneity and sample size indicated that as sample size increased, the prevalence of Enterobius vermicularis among children in Iran also increased (p = 0.578). Additionally, with an increase in the year of conducting the studies, the prevalence of Enterobius vermicularis among children in Iran decreased (p < 0.05).

Conclusion

The findings of this study show a relatively high prevalence of Enterobius vermicularis among children in Iran. We recommend health policymakers recognize the significance of this issue and take necessary measures to reduce the incidence of this infectious agent in children, implementing more effective preventive measures through mass media and educational campaigns.

Intestinal parasite infections associated with sociodemographic and seasonal factors in the Western Amazon

Intestinal parasites are a constant public health problem in the Amazon region, with a high prevalence of cases related to poor sanitary conditions. We investigated the sociodemographic and seasonal factors associated with human intestinal parasite infections in an area of the Western Amazon, Brazil, from September 2017 to August 2019. Data were collected using a database available at the Diagnostic Support Centre (Centro de Apoio ao Diagnóstico, CAD) of the Municipality of Rio Branco, on positive diagnoses for intestinal parasites. Among the 53,200 samples analysed, 18.3% (n = 9712) were positive. Of these, 96.4% (n = 9363) and 3.6% (n = 349) were protozoan and helminthic infections, respectively. Males showed higher odds ratio (OR) for Enterobius vermicularis infection (OR: 2.3) and giardiasis (OR: 1.9) and lower OR for Endolimax nana (OR: 0.9) and Entamoeba coli (OR: 0.9) infections. Individuals aged ≥ 15 presented higher OR for Strongyloides stercoralis (OR: 3.4), hookworms (OR: 2.3), and almost all protozoan infections than younger individuals. In the dry season, the OR for hookworms (OR: 1.5), Iodamoeba butschlii (OR: 1.4), and Endolimax nana (OR: 1.3) infections was higher than that in the rainy season, including a high chance of polyparasitism (OR: 1.6). We concluded that there was a significant difference between the different types of intestinal parasites, particularly protozoa, with high OR in the dry season and for certain groups.

Enterobiasis among Yemeni children: a cross-sectional study

Enterobiasis is a highly infectious parasitic disease spreading worldwide including Yemen. Therefore, this study aimed to investigate the prevalence and risk factors of enterobiasis among Yemeni children in Dhamar governorate. A total of 402 children (aged 1-12 years) participated in this cross-sectional survey carried out at Thamar University Al-Wahdah Teaching Hospital (TUWTH), between 2018 and 2019. Enterobius vermicularis infection was examined using the adhesive tape technique. Association between risk factors and enterobiasis were measured by prevalence ratio (PR). The overall prevalence of enterobiasis was found to be 29.4% (118/402). Risk factors that showed independent association with the infection were child's care responsibility (PR = 1.90; 95% CI = 1.37-2.63; P = 0.001); irregular washing hands before meals (PR = 2.01; 95% CI = 1.32-3.05; P = 0.003); habit of nail biting or cutting by teeth (PR = 1.61; 95% CI = 1.18-2.21; P = 0.002); habit of putting toys or pen in mouth (PR = 1.58; 95% CI = 1.19-2.10; P = 0.002); frequent anal itching (PR = 1.46; 95% CI = 1.10-1.93; P = 0.016); using anthelmintic during the last six months (PR = 1.68; 95% CI = 1.20-2.36; P = 0.011); and parents have no knowledge on preventive measures (PR = 1.62; 95% CI = 1.04-2.53; P = 0.036). Prevalence of enterobiasis among Yemeni children in Dhamar governorate is high with higher infection rate among those aged 1-6 years. Health education and mass treatment are highly recommended among this poor population.

Contamination of fresh produce sold on the Italian market with Cyclospora cayetanensis and Echinococcus multilocularis

To investigate the presence of Cyclospora cayetanensis, Toxoplasma gondii and Echinococcus spp. in fresh produce sold in Italy, 324 locally produced 'ready-to-eat' (RTE) mixed-salad packages belonging to three brands and 324 berries packages (blueberries and blackberries imported from Peru and Mexico, respectively, and raspberries grown in Italy) were purchased at retail. Nine individual packages from each of the six types of fresh produce were collected monthly for one year, and with the same produce pooled, this resulted in a total of 72 pools for the whole year. Using microscopy (FLOTAC), a Cyclospora-like oocyst was detected in a blueberry sample and a taeniid egg was detected in a RTE-salad sample. Molecular tools confirmed these to be C. cayetanensis and Echinococcus multilocularis, respectively. Toxoplasma gondii was not detected in any of the samples. This study shows for the first time in Europe that imported berries on the Italian market may be contaminated with C. cayetanensis and RTE salads grown in Italy with E. multilocularis. The results indicate a new epidemiological scenario and highlight that current management of fresh produce, locally produced or imported, does not ensure products are free from parasite contamination.

Intestinal protozoa and helminths in ulcerative colitis and the influence of anti-parasitic therapy on the course of the disease

PURPOSE

The aim of this study is to determine the prevalence of intestinal helminths and protozoa in patients with ulcerative colitis (UC) and to estimate the influence of the anti-parasitic therapy on the course of the disease.

METHODS

The study was conducted at the Research Institute of Epidemiology, Microbiology and Infectious Diseases and Coloproctology Department of the Republic Clinical Hospital №1 of the Ministry of Health of the Republic of Uzbekistan. One hundred UC patients and 200 healthy individuals were examined by triple coproscopy. Additionally, 20, 25 and 22 UC patients with Blastocystis infection were treated with nitazoxanide (1.0 g/day), mesalazine (1.5-2 g/day) or a combination of nitazoxanide (1.0 g/day) and mesalazine (≥1.5-2 g/day) for 14 consecutive days, respectively. Parasitological, clinical and endoscopic examinations were conducted before therapy, immediately after and 6 and 12 weeks after therapy completion.

RESULTS

The overall prevalence of helminths in UC patients and control individuals was not significantly different: 14±3.4% and 8.5±1.9%, respectively (OR: 1.7524; 95% CI: 0.8258 to 3.7186; P=0.1). Giardia lamblia was the most prevalent parasite in both groups, but the difference compared to the control was insignificant (OR: 0.4565; 95% CI: 0.2020 to 1.0318; P=0.05). A significantly higher prevalence of Blastocystis sp., Chilomastix mesnili and Iodamoeba butschlii in UC patients compared to control individuals was found (P<0.0005): 65.0%, 14.0% and 22.0%, respectively. During all follow-up periods, the clinical response and clinical remission were not statistically different between the groups (P>0.05). Mucosal healing immediately and 6 weeks after therapy with a combination of nitazoxanide with mesalazine was significantly better than with a monotherapy of nitazoxanide, respectively (P<0.05). UC patients treated with a combination of nitazoxanide with mesalazine showed better mucosal healing than in patients treated with a monotherapy of mesalazine (P>0.05).

CONCLUSIONS

Diagnosis of Blastocystis sp. should be introduced in the complex examination of UC patients. Further clinical studies are necessary for assessment of the efficiency of anti-Blastocystis therapy in UC patients.

The association between the lack of safe drinking water and sanitation facilities with intestinal Entamoeba spp infection risk: A systematic review and meta-analysis

Intestinal protozoa infections are responsible for considerable morbidity and mortality, especially where the exposed population suffers from a lack of drinking water and sanitation facilities. In this study, the association between the lack of safe drinking water and sanitation (toilet) facilities with intestinal Entamoeba spp infection in the children (5-11 years), adult (18-55 years), and all age (5-55 years) were assessed. For this purpose, some of the international databases such as Scopus, PubMed, Web of Science, and Embase were screened to up to 7 June 2019 in order to retrieve the related citations. Also, the pooled odds ratios (ORs) following 95% confidence intervals (CIs) were calculated using a random-effects model. Twenty-nine articles with 36 studies were included while the OR extracted or calculated by using 2 × 2 contingency tables. However, the ingestion of contaminated water insignificantly can increase the odds ratio (OR) of Entamoeba spp infection (OR 1.01, (95% confidence interval [CI] 0.58 to 1.43), no access to sanitation (toilet) facilities significantly can increase odds of Entamoeba spp infection (OR 1.18, 95% CI 1.05 to 1.32). The meta-regression analysis showed that over time, odds of intestinal Entamoeba spp infection increased in both lack of safe drinking water (Coefficient: 3.24, P-value < 0.01) and sanitation (toilet) facilities (Coefficient: 2.36, P-value < 0.05) subgroups. Considering the findings, lack of safe drinking water resulted in a further increase in intestinal Entamoeba spp infection among adult (OR: 2.76), children (OR = 0.57) and all age groups (OR: 1.50), and also lack of sanitation (toilet) facilities resulted in further increase intestinal Entamoeba spp infection in children (OR: 1.06), adult (OR: 1.26) and all age (OR: 1.16). In this context, the lack of safe drinking water and sanitation facilities (toilet) was associated with a high risk of intestinal Entamoeba spp infection. Further attempts to providing public health facilities can control the prevalence of intestinal Entamoeba spp.

Molecular genotyping of Blastocystis spp. in wild mammals from Mexico

Blastocystis spp. are common intestinal parasites found worldwide in humans and a wide range of animals. They exhibit extensive genetic diversity; currently, 17 subtypes (STs) and some groups called non-mammalian and avian STs (NMASTs) have been proposed. In addition, a large variety of animals have been reported as hosts of the parasite, and new hosts and STs are still being described. In this study, Blastocystis infection of wild animals in two sylvatic areas of Mexico was surveyed. Of one hundred twenty-four fecal samples, six were positive for Blastocystis: specifically, one sample from an opossum, one sample from a bat, and four samples from different species of rodents. ST4, ST17, and nucleotide sequences similar to Blastocystis lapemi were identified based on SSU rDNA sequences. To our knowledge, this is the first report to investigate species poorly or not previously evaluated for Blastocystis infection. Mammals having different niches and geographical distribution were infected with similar genetic type of Blastocystis, so that we suggest that local water or food sources could play an important role in Blastocystis transmission and ST maintenance in wild animals. Additionally, there are STs with scarce genetic variation, suggesting that they could be highly adapted to their hosts. These data contribute to our understanding of the host range and genetic diversity of Blastocystis.

Cyclospora cayetanensis and Cyclosporiasis: An Update

Cyclospora cayetanensis is a coccidian parasite of humans, with a direct fecal-oral transmission cycle. It is globally distributed and an important cause of foodborne outbreaks of enteric disease in many developed countries, mostly associated with the consumption of contaminated fresh produce. Because oocysts are excreted unsporulated and need to sporulate in the environment, direct person-to-person transmission is unlikely. Infection by C. cayetanensis is remarkably seasonal worldwide, although it varies by geographical regions. Most susceptible populations are children, foreigners, and immunocompromised patients in endemic countries, while in industrialized countries, C. cayetanensis affects people of any age. The risk of infection in developed countries is associated with travel to endemic areas and the domestic consumption of contaminated food, mainly fresh produce imported from endemic regions. Water and soil contaminated with fecal matter may act as a vehicle of transmission for C. cayetanensis infection. The disease is self-limiting in most immunocompetent patients, but it may present as a severe, protracted or chronic diarrhea in some cases, and may colonize extra-intestinal organs in immunocompromised patients. Trimetoprim-sulfamethoxazole is the antibiotic of choice for the treatment of cyclosporiasis, but relapses may occur. Further research is needed to understand many unknown epidemiological aspects of this parasitic disease. Here, we summarize the biology, epidemiology, outbreaks, clinical symptoms, diagnosis, treatment, control and prevention of C. cayetanensis; additionally, we outline future research needs for this parasite.