Prevalence of intestinal protozoa infection among school-aged children on Pemba Island, Tanzania, and effect of single-dose albendazole, nitazoxanide and albendazole-nitazoxanide

Introducing the NUATEI Consortium: A Mexican Research Program for the Identification of Natural and Synthetic Antimicrobial Compounds for Prevalent Infectious Diseases

The need for new drugs to treat human infections is a global health concern. Diseases like tuberculosis, trypanosomiasis, amoebiasis, and AIDS remain significant problems, especially in developing countries like Mexico. Despite existing treatments, issues such as resistance and adverse effects drive the search for new alternatives. Herein, we introduce the NUATEI research consortium, made up of experts from the Institute of Biomedical Research at UNAM, who identify and obtain natural and synthetic compounds and test their effects against human pathogens using in vitro and in vivo models. The consortium has evaluated hundreds of natural extracts and compounds against the pathogens causing tuberculosis, trypanosomiasis, amoebiasis, and AIDS, rendering promising results, including a patent with potential for preclinical studies. This paper presents the rationale behind the formation of this consortium, as well as its objectives and strategies, emphasizing the importance of natural and synthetic products as sources of antimicrobial compounds and the relevance of the diseases studied. Finally, we briefly describe the methods of the evaluation of the compounds in each biological model and the main achievements. The potential of the consortium to screen numerous compounds and identify new therapeutic agents is highlighted, demonstrating its significant contribution to addressing these infectious diseases.

Epidemiology and multiple colonization of gastrointestinal pathogens in rural Tanzanian children with and without diarrhea: A case-control study

Diarrheal diseases are important causes of morbidity and mortality, worldwide. The occurrence of multiple pathogens in stool samples of symptomatic and asymptomatic individuals in resource-limited countries have been repeatedly described. In this study, we assessed the differentiated effects of combined pathogen detections on recorded symptoms. A case-control study was conducted among 620 under-five-year-old children in rural northeastern Tanzania with emphasis of multiple detection. The median age of children was 11 months (IQR = 7, 20), and 52.1% were male. Cases (50.2%, n = 157) were less likely than controls (64.5%, n = 198) to have multiple colonization with gastrointestinal tract (GIT) pathogens. The children's age was positively associated with the likelihood of harboring multiple GIT pathogens [OR, 1.02, 95% CI = 1.01, 1.04]. Shigella spp./enteroinvasive Escherichia coli (EIEC) [OR = 2.80, 95% CI 1.62, 4.83] and norovirus [OR = 2.04, 95% CI 1.23, 3.39] were more common in cases and were strongly associated with diarrhea, while enteroaggregative E. coli (EAEC) [OR = 0.23, 95%CI 0.17-0.33] were more common in controls. Diarrheal diseases in under-five children from rural Tanzania are likely to be due to infections with Shigella spp./EIEC, and norovirus with strongly age-dependent associations.

Molecular identification of Entamoeba spp. in humans and cattle in Baghdad, Iraq

Background and Aim

A total of 10% of the global population succumbs to amoebiasis yearly, equating to 50,000-100,000 recorded fatalities. It is closely associated with contaminated food and water supplies due to human feces. The disease's pathophysiology remains a subject of ongoing debate among experts. Some experts attribute the role of the host's conditions, parasite species and strain, and infection intensity in eliciting clinical symptoms. The aim of this study was to perform molecular identification of Entamoeba species isolated from humans and cattle.

Materials and Methods

Stool samples from three hundred patients and one hundred cattle were collected from different regions, age groups, and sexes in Baghdad for microscopic examination. One hundred randomly chosen patient and cattle stool samples underwent microscopic examination and conventional polymerase chain reaction (PCR) targeting the 18S rRNA gene. Phylogenetic tree analyses were performed for Entamoeba species identification.

Results

The infection rate in humans differed significantly (p < 0.05) between age groups and genders, totaling 38%. The infection rate in cattle, determined by conventional PCR, differed significantly (p < 0.05) between age groups and genders, amounting to 58%. Ten PCR products with positive results were sequenced and deposited in GenBank database. Sequence analysis detected that Eight sequences belong to E. histolytica (OM268853.1, OM268854.1, OM268855.1, OM268857.1, OM268858.1, OM268860.1, OM268861.1, and OM268862.1) and two sequences belong to E. dispar (OM268856.1 and OM268859.1) in humans, while 10 sequences (ON724165.1 to ON724174.1) belongs to E. histolytica in cattle.

Conclusion

The increased susceptibility of cattle to E. histolytica suggests a considerable role in human infection and substantial public health risks. Further research should be conducted on the many virulence factors such as HM1:IMSS strain, cysteinprotease (Cp1), Gal/lectin, etc. of E. histolytica and E. dispar.

Prevalence of intestinal parasitic infections and associated risk factors among patients attending Debarq Primary Hospital, northwest Ethiopia

Intestinal parasitic infections (IPIs) are major public health problems in developing countries. This study was conducted to determine the prevalence and associated risk factors of IPIs at Debarq Primary Hospital in northwest Ethiopia. A health facility-based cross-sectional study was conducted from March 2022 to June 2022. The study participants were recruited from patients who visited Debarq Primary Hospital during the study period. Stool samples were collected from each participant and examined for intestinal parasites using direct wet-mount and formal-ether concentration techniques. Socio-demographic data were collected using a structured questionnaire. Out of 422 individuals examined, 33.64% were infected with at least one intestinal parasite species. Entamoeba histolytica/dispar, Giardia intestinalis, Ascaris lumbricoides, and hookworm were found in 12.79%, 8.53%, 7.10%, and 1.65% of the participants, respectively. Double and triple parasite infections were found in 2.37% and 0.23% of the participants, respectively. A habit of eating unwashed vegetables (Adjusted odds ratio (AOR) = 9.98, 95% confidence interval (CI) = 2.68-37.14) and low income (AOR = 6.66, 95% CI = 1.87-23.70) were associated with increased odds of IPIs. Participants with a habit of hand washing after using the toilet had 0.05 (95% CI = 0.13-0.22) lower odds of IPIs than those who did not. In conclusion, IPIs are common among Debarq Primary Hospital patients and are associated with factors such as low income, not washing hands after using the toilet, and eating unwashed vegetation, necessitating control and prevention efforts in the study area that include health education and the provision and use of sanitary facilities.

Prevalence of Intestinal Parasites and Associated Risk Factors among Diarrheal Patients Attending Negelle Borena General Hospital: A Case-Control Study

Background

In tropical countries, intestinal protozoal parasitic infections are among the common infections causing significant morbidity and mortality. Thus, the present study was conducted to assess the status of intestinal protozoal parasitic infections among diarrheal patients attending Negelle Borena General Hospital and investigate the possible risk factors for the infection.

Methods

A case-control study design was employed in the study. The intestinal protozoal parasites were detected using a wet-mount, stool concentration, and modified Ziehl-Neelsen methods. The crude and adjusted odd ratios were considered to identify the associated risk factors for intestinal protozoal parasitic infections among the study participants.

Results

The overall status of parasitic infection was 46.88% in cases and 27.08% in the control groups. The most prevalent protozoal infection was Giardia lamblia (9.38%) and followed by Entamoeba histolytica/dispar (6.25%) in the cases. The highest prevalence of the infection was detected in the age groups that varied from 6 to 10 years in cases (71%). The enteric G. lamblia and E. histolytica/dispar were found to be 33.3% and 9.1%, respectively, in the age groups of 6-10 years in cases. Based on sex, 56.50% and 27.30% of protozoal (parasitic) infections were revealed by females in the cases and control groups, respectively, indicating a significant variation (P < 0.05). The education level (illiteracy), absence of toilet usage, no hand washing after toilet and before eating as significant risk factors for patient's infection with G. lamblia, E. histolytica, and Cryptosporidium spp. (P < 0.05, AOR = 1-14). However, eating raw fruit and vegetables was also found as a major risk factor for E. histolytica (P < 0.05, AOR = 6.2) 40. Moreover, the residence of the patients was also indicated as a plus risk factors for the infection to be occurred by Cryptosporidium spp. in the study participants (P > 0.95, AOR = 0.2).

Conclusion

The prevalence of intestinal protozoal parasitic infection showed variation based on age, sex, and educational background of the study participants. Therefore, awareness creating training should be provided to the Negelle area communities so as to minimize the parasitic infection.

The phenotype of type 1 diabetes in sub-Saharan Africa

The phenotype of type 1 diabetes in Africa, especially sub-Saharan Africa, is poorly understood. Most previously conducted studies have suggested that type 1 diabetes may have a different phenotype from the classical form of the disease described in western literature. Making an accurate diagnosis of type 1 diabetes in Africa is challenging, given the predominance of atypical diabetes forms and limited resources. The peak age of onset of type 1 diabetes in sub-Saharan Africa seems to occur after 18-20 years. Multiple studies have reported lower rates of islet autoantibodies ranging from 20 to 60% amongst people with type 1 diabetes in African populations, lower than that reported in other populations. Some studies have reported much higher levels of retained endogenous insulin secretion than in type 1 diabetes elsewhere, with lower rates of type 1 diabetes genetic susceptibility and HLA haplotypes. The HLA DR3 appears to be the most predominant HLA haplotype amongst people with type 1 diabetes in sub-Saharan Africa than the HLA DR4 haplotype. Some type 1 diabetes studies in sub-Saharan Africa have been limited by small sample sizes and diverse methods employed. Robust studies close to diabetes onset are sparse. Large prospective studies with well-standardized methodologies in people at or close to diabetes diagnosis in different population groups will be paramount to provide further insight into the phenotype of type 1 diabetes in sub-Saharan Africa.

Molecular characterization of Blastocystis subtypes in symptomatic patients from the southern region of Syria

Blastocystis sp. is an enteric protist found in humans and a wide range of animal hosts. Genetic variations were established among the 38 different subtypes detected so far, 14 of which are commonly found in human and animal hosts. The aim of the present study is to estimate the prevalence of the common Blastocystis subtypes and evaluate the possible correlation with several variables (gender, age, symptoms, domestic animals…), among patients from the southern region of Syria. Fecal samples were collected from individuals suffering from gastrointestinal complaints. Microscopic examination along with genotype analyses using seven pairs of subtype-specific primers was performed. Our results revealed the presence of Blastocystis sp. in 46 isolates out of the 60 samples microscopically studied (76.7%); single infection was detected in 24 isolates whereas co-infection with other protozoa was identified in 22 ones. Molecular detection targeting the SSU rRNA gene revealed a 100% positive presence of Blastocystis sp. in all the samples. Genotyping results detected the presence of five different subtypes (ST1-ST5) with varying proportions. However, ST1 was the dominant subtype observed (66.7%). Mixed subtype infections were found in 9 isolates (15%). Three samples remained undefined, nonetheless. Our statistical results showed no significant correlation between Blastocystis STs infection and the different studied variables. In conclusion, this study provides the first genetic characterization of Blastocystis subtypes prevalence in patients from the southern region of Syria. ST1 distribution was highly predominant. Further molecular studies are needed to estimate the prevalence of Blastocystis sp. infection in other regions in Syria and to understand the epidemiology and sources of transmission to humans.

An Overview of Mucosa-Associated Protozoa: Challenges in Chemotherapy and Future Perspectives

Parasitic infections caused by protozoans that infect the mucosal surfaces are widely neglected worldwide. Collectively, Entamoeba histolytica, Giardia lamblia, Cryptosporidium spp. and Trichomonas vaginalis infect more than a billion people in the world, being a public health problem mainly in developing countries. However, the exact incidence and prevalence data depend on the population examined. These parasites ultimately cause pathologies that culminate in liver abscesses, malabsorption syndrome, vaginitis, and urethritis, respectively. Despite this, the antimicrobial agents currently used to treat these diseases are limited and often associated with adverse side effects and refractory cases due to the development of resistant parasites. The paucity of drug treatments, absence of vaccines and increasing problems of drug resistance are major concerns for their control and eradication. Herein, potential candidates are reviewed with the overall aim of determining the knowledge gaps and suggest future perspectives for research. This review focuses on this public health problem and focuses on the progress of drug repositioning as a potential strategy for the treatment of mucosal parasites.

Prevalence of Intestinal Protozoa and Soil Transmitted Helminths Infections among School Children in Jaragedo Town, South Gondar Zone of Ethiopia

Background

Parasitism is a relationship where one, the parasite, harms the host or lives at the expense of the host. Intestinal parasites (protozoa and STHs-soil-transmitted helminths) cause gastrointestinal tract infection in humans and animals. Intestinal parasitic infections (IPIs) predominate the tropics and subtropics and affect poor countries, where school children suffer the most. To prevent and control these infections, local risk factors must first be identified. The aim of the study was to determine the prevalence of intestinal parasitic infections and associated risk factors among school children in Jaragedo town schools, South Gondar Zone of Ethiopia.

Methods

A cross-sectional study was conducted from October 2018 to April 30, 2019, involving 396 students from one elementary and one secondary school. Stratified simple random sampling method was used. A questionnaire was prepared to collect sociodemographic and socioeconomic data of the study subjects. Stool samples were collected and examined using formalin-ether concentration technique. Data were analyzed using SAS software version 9.4. Descriptive statistics were used to give a clear picture of population characteristics. Logistic regression was also used to determine the relationship between dependent variables (primary infection) with independent (explanatory) variables using SAS software.

Results

Results showed that the overall prevalence of intestinal parasitic infections was 65.4%. E. histolytica was the most prevalent intestinal parasite (12–14%) followed by G. lamblia (8–9%); other parasites could not infect more than 5% of the study subjects. Generally, parasitism did not vary between the sexes. The logistic regression analysis showed that grade, level of students, water source, habit of consuming raw meat, and level of income had a strong effect on intestinal parasitic infection (P < 0.05). Other explanatory variables were not significant (P > 0.05). High prevalence of parasites indicates improper disposal of waste, low socioeconomic level, low living standard, and poor water quality.

Conclusion

Therefore, short-term and long-term intervention strategies are required to minimize rates of infection.

Conflict-related health research in Syria, 2011-2019: a scoping review for The Lancet - AUB Commission on Syria

BACKGROUND

The volume of health-related publications on Syria has increased considerably over the course of the conflict compared with the pre-war period. This increase is largely attributed to commentaries, news reports and editorials rather than research publications. This paper seeks to characterise the conflict-related population and humanitarian health and health systems research focused inside Syria and published over the course of the Syrian conflict.

METHODS

As part of a broader scoping review covering English, Arabic and French literature on health and Syria published from 01 January 2011 to 31 December 2019 and indexed in seven citation databases (PubMed, Medline (OVID), CINAHL Complete, Global Health, EMBASE, Web of Science, Scopus), we analyzed conflict-related research papers focused on health issues inside Syria and on Syrians or residents of Syria. We classified research articles based on the major thematic areas studied. We abstracted bibliometric information, study characteristics, research focus, funding statements and key limitations and challenges of conducting research as described by the study authors. To gain additional insights, we examined, separately, non-research publications reporting field and operational activities as well as personal reflections and narrative accounts of first-hand experiences inside Syria.

RESULTS

Of 2073 papers identified in the scoping review, 710 (34%) exclusively focus on health issues of Syrians or residents inside Syria, of which 350 (49%) are conflict-related, including 89 (25%) research papers. Annual volume of research increased over time, from one publication in 2013 to 26 publications in 2018 and 29 in 2019. Damascus was the most frequently studied governorate (n = 33), followed by Aleppo (n = 25). Papers used a wide range of research methodologies, predominantly quantitative (n = 68). The country of institutional affiliation(s) of first and last authors are predominantly Syria (n = 30, 21 respectively), the United States (n = 25, 19 respectively) or the United Kingdom (n = 12, 10 respectively). The majority of authors had academic institutional affiliations. The most frequently examined themes were health status, the health system and humanitarian assistance, response or needs (n = 38, 34, 26 respectively). Authors described a range of contextual, methodological and administrative challenges in conducting research on health inside Syria. Thirty-one publications presented field and operational activities and eight publications were reflections or first-hand personal accounts of experiences inside Syria.

CONCLUSIONS

Despite a growing volume of research publications examining population and humanitarian health and health systems issues inside conflict-ravaged Syria, there are considerable geographic and thematic gaps, including limited research on several key pillars of the health system such as governance, financing and medical products; issues such as injury epidemiology and non-communicable disease burden; the situation in the north-east and south of Syria; and besieged areas and populations. Recognising the myriad of complexities of researching active conflict settings, it is essential that research in/on Syria continues, in order to build the evidence base, understand critical health issues, identify knowledge gaps and inform the research agenda to address the needs of the people of Syria following a decade of conflict.

Soil-transmitted helminths, intestinal protozoa and Clonorchis sinensis infections in southeast China

BACKGROUND

Extensive parasitic diseases epidemiology in Zhejiang province has not been carried out since the second national survey in 2004. Therefore, dynamics in prevalence and infection pattern of the major intestinal parasites should be explored.

METHODS

The distribution of three parasites including soil-transmitted helminths (STH), intestinal protozoa and C. sinensis in Zhejiang from 2014 to 2015 were explored. Kato-Katz technique was used for STH and C. sinensis detection, whereas transparent adhesive paper anal swab was used for pinworm detection, and iodine smear was used for protozoa detection. A questionnaire survey on alimentary habits and sanitary behaviors was conducted in half of the studied counties.

RESULTS

This study recruited 23,552 participants: 19,935 from rural and 3617 from urban area. Overall prevalence of intestinal helminth infections was 1.80%. In this study, seven helminth species were identified including A. duodenale, N. americanus, Trichuris trichiura, Ascaris lumbricoides, C. sinensis, Fasciolopsis buski and pinworm. The average prevalence of STH infection was 1.71%: 1.94% in rural and 0.44% in urban area. Hookworm was the most prevalent infection at 1.58%: 1.79% in rural and 0.44% in urban area. Prevalence varied considerably in the studied counties. Prevalence was highest in Yongkang county at 10.25%. Only 2.79% of children from rural area were infected with pinworm. A proportion of 0.40% of rural participants were infected with protozoa, whereas Endolimax nana was the most prevalent at 0.23%. C. sinensis showed infection only in one man. Awareness on C. sinensis was 24.47% in rural and 45.96% in urban area, respectively.

CONCLUSIONS

Prevalence of STH and protozoa infections declined considerably whereas C. sinensis infections remained few in Zhejiang province compared with the prevalence reported in previous large scale surveys (19.56% for national STH infection in 2004, 18.66% and 4.57% for provincial STH and protozoa infection, respectively in 1999). The findings of this study showed that hookworm, mainly N. americanus remained a parasitic threat to population health, mainly in the central and western Zhejiang. Therefore, more health education regarding fertilization and farming habits is necessary in rural areas. The awareness concerning hookworm infection should be reinforced.

Evaluation of health appraisal project of primary school children: a study in Egypt

BACKGROUND

School Health insurance (SHI) is working in Egypt since 2003. However, there were no impact indicators that inform policy makers about health status of school children. Therefore, the school health project was conducted by Arab Medical Union (AMU) Medical Syndicate in cooperation with Ministry of Education (MOE), Ministry of Health and Population (MOHP) and Public Health Department, Cairo University to conduct comprehensive medical services to primary school children and to assess the impact of the SHI and the efficiency of AMU project to promote health of children.

METHODS

In-depth interview with policy makers in MOHP, MOE, SHI and secondary analysis of AMU documents. A systematic random sample of 7000 students (7-10 years) was selected which formed 10% of the examined children in AMU project and proportionally distributed in 355 schools in seven Districts in Fayoum Governorate.

RESULTS

SHI was ineffective in providing preventive services to school children. The AMU project was efficient in covering 82% of the targeted students with clinical, preventive and referral services with estimated cost per student were 54.8LE. Clinical findings showed anaemia the major problem (84%), dental (33%), hair/scalp (9%) and visual errors (6%).

CONCLUSION

The current Primary Health Care facilities needs to improve the quality preventive and curative health services provided to school children. Also, providing health services through medical conveys was of high cost and unsustainable.

Anti-Giardia Drug Discovery: Current Status and Gut Feelings

Giardia parasites are ubiquitous protozoans of global importance that impact a wide range of animals including humans. They are the most common enteric pathogen of cats and dogs in developed countries and infect ∼1 billion people worldwide. While Giardia infections can be asymptomatic, they often result in severe and chronic diseases. There is also mounting evidence that they are linked to postinfection disorders. Despite growing evidence of the widespread morbidity associated with Giardia infections, current treatment options are limited to compound classes with broad antimicrobial activity. Frontline anti-Giardia drugs are also associated with increasing drug resistance and treatment failures. To improve the health and well-being of millions, new selective anti-Giardia drugs are needed alongside improved health education initiatives. Here we discuss current treatment options together with recent advances and gaps in drug discovery. We also propose criteria to guide the discovery of new anti-Giardia compounds.

Ascariasis, Amebiasis and Giardiasis in Mexican children: distribution and geographical, environmental and socioeconomic risk factors

The aim of this study is to provide an overview of the geographical distribution of Ascariasis, Amebiasis and Giardiasis, and to identify specific geographical, socioeconomic and environmental factors that are associated with the incidence of these infections in Mexican children. We made use of publicly available data that was reported by federal organizations in Mexico for the year 2010. The contribution of geographical, socioeconomic and environmental factors to the incidence of infections was assessed by a multivariable regression model using a backwards selection procedure. A. lumbricoides incidence was associated with mean minimum temperature of the state, the state-wide rate of households without access to piped water and toilet, explaining 77% of the incidence of A. lumbricoides infections. Mean minimum precipitation in the state, the rate of households without access to a toilet, piped water and sewage system best explained (73%) the incidence of E. histolytica infections. G. lamblia infections were only explained by the latitude of the state (11%). In addition to the well-known socioeconomic factors contributing to the incidence of A. lumbricoides and E. histolytica we found that temperature and precipitation were associated with higher risk of infection.

Malaria coinfection with Neglected Tropical Diseases (NTDs) in children at Internally Displaced Persons (IDP) camp in Benin City, Nigeria

Malaria and Neglected Tropical Diseases (NTDs) are highly endemic in poorer countries of the world. The research investigated the prevalence of parasitic infections among children in Internally Displaced Persons (IDP) camp in Benin City. Faecal, urine and blood specimen were collected from 184 children (100 males and 84 females) aged 6–15. Blood samples were prepared using thick film method and analyzed microscopically. Direct smear technique was employed for faecal sample and sedimentation method to concentrate ova from the urine sample. Ten species of parasites were identified in this study. The predominant species were Plasmodium falciparum (67.93%), Entamoeba histolytica (67.93%) and Giardia duodenalis (59.78%). Plasmodium falciparum and E. histolytica were most prevalent in both sexes, with P. falciparum infecting 68% males and 67.86% females while E. histolytica infected 66% males and 70.24% females (P = 0.24). Mixed infections with blood and intestinal parasites were recorded in 41.18% in age group 5–10 and 47.90% in age group 11–15 (P < 0.5). Also, mixed infections with blood and intestinal parasites were detected in 45% males and 50% females (P = 0.51). Urinary schistosomiasis was recorded in 28.80% of the participants. Parasitic infections especially P. falciparum malaria and amoebiasis were predominant among the children. Therefore, our findings call for specific intervention programmes to reduce parasite intensity and morbidity in the children. Environmental and personal hygiene should be implemented in order to curb parasitosis in the study area.

Prevalence of Intestinal Parasitic Infections and Associated Water, Sanitation, and Hygiene Risk Factors among School Children in Mwea Irrigation Scheme, Kirinyaga County, Kenya

School children bear a significant burden of intestinal parasitic infections. Because they spend most of their time at home and school, it is necessary to identify the key water, sanitation, and hygiene (WASH) factors associated with these infections in both environments. This was a cross-sectional survey conducted in Mwea West, Kirinyaga County. 180 primary school children aged 8–14 years were randomly selected from three schools (Mianya, Mbui Njeru, and Mukou primary schools). Questionnaires and checklists were administered and single stool samples were collected. Stool samples were microscopically examined for Schistosoma mansoni, soil-transmitted helminths, and protozoan infections. Data on WASH were obtained at home and school. The factors significantly associated with S. mansoni and intestinal protozoa infections in the school children were determined using univariable and multivariable logistic regression models reporting the odds ratio at 95% confidence intervals. The overall prevalence of S. mansoni and intestinal protozoa infections was 70.5% (95% CI: 59.1–84.3) and 32.7% (95% CI: 26.8–40.1), respectively. Only one case of STH (A. lumbricoides) was identified. The prevalence of coinfections of S. mansoni and intestinal protozoa infections was 22.8% (95% CI: 19.2–27.1). An increased prevalence of S. mansoni infection was associated with children above 12 years (aOR = 3.19, p=0.015), those in Mianya primary (aOR = 1.23, p=0.001), those in Mukou primary (aOR = 3.19, p=0.001), and reported behavior of wearing shoes at home (aOR = 1.67, p=0.010). However, handwashing behavior after defecation at home (aOR = 0.39, p=0.001) was protective against S. mansoni infection. For any protozoan infection, male children had increased odds of infection (aOR = 2.41, p=0.001) while use of wiping material (aOR = 0.55, p=0.019) and water contact (aOR = 0.32, p=0.001) was protective against intestinal protozoa infections. Infections with S. mansoni and any protozoa and their coinfection were present. Findings revealed that several hygiene factors were protective against infections while other were risk factors. Therefore, deworming should be complemented with behavior education on hygienic habits.

Prevalence and factors associated with intestinal parasitic infection among under-five children in and around Haro Dumal Town, Bale Zone, Ethiopia

BACKGROUND

Intestinal parasitic infection is diversified illness and diseases caused millions morbidity among under-five children lives in developing countries particularly vulnerable rural communities. Deworming coverage in such community is low. The aim of this study was to determine the prevalence and associated risk factors of intestinal parasitic infections (IPIs) among under-five children live in and around Haro Dumal Town.

METHODS

Community-based cross-sectional study was conducted in 561 randomly selected under-five children from June to August, 2018. The stool samples were collected and examined by basic parasitological techniques. Data related to socio-demographic and risk factors were collected using a self administered questionnaire. Statistical data analysis was done using SPSS version 21 and the bivariate and multivariate logistic regression used to compute the association between variables. P-value of < 0.05 was statistical significance.

THE RESULTS

Of the 561 total under-five children, 216 (38.5%) were found to be infected with intestinal parasites. E.histolytica/dispar (15.3%) was the most prevalent parasite, followed by hook worm (14.4%) and T.trichuria (13.9%). Regarding risk factors, geo-phage [(AOR = 4.7; 95%CI: 2.0-10.4), P < 0.001], tungiasis [(AOR = 3.1; 95%CI: 1.1-6.6), P < 0.001], eating raw vegetable [(AOR = 1.3; 95%CI: 1.4-3.3), P < 0.001] were significantly associated with intestinal parasitic infections.

CONCLUSION

Intestinal parasitic infections (IPIs) were found to be highly prevalent in the study area. Hence, improving sanitation, controlling ecto-parasite such as tungiasis, provision of safe water and successful mass-deworming are important.

Giardia duodenalis infection in the context of a community-based deworming and water, sanitation and hygiene trial in Timor-Leste

Background

Giardiasis is a common diarrhoeal disease caused by the protozoan Giardia duodenalis. It is prevalent in low-income countries in the context of inadequate access to water, sanitation and hygiene (WASH), and is frequently co-endemic with neglected tropical diseases such as soil-transmitted helminth (STH) infections. Large-scale periodic deworming programmes are often implemented in these settings; however, there is limited evidence for the impact of regular anthelminthic treatment on G. duodenalis infection. Additionally, few studies have examined the impact of WASH interventions on G. duodenalis.

Methods

The WASH for WORMS cluster randomised controlled trial was conducted in remote communities in Manufahi municipality, Timor-Leste, between 2012 and 2016. All study communities received four rounds of deworming with albendazole at six-monthly intervals. Half were randomised to additionally receive a community-level WASH intervention following study baseline. We measured G. duodenalis infection in study participants every six months for two years, immediately prior to deworming, as a pre-specified secondary outcome of the trial. WASH access and behaviours were measured using questionnaires.

Results

There was no significant change in G. duodenalis prevalence in either study arm between baseline and the final study follow-up. We found no additional benefit of the community-level WASH intervention on G. duodenalis infection (relative risk: 1.05, 95% CI: 0.72–1.54). Risk factors for G. duodenalis infection included living in a household with a child under five years of age (adjusted odds ratio, aOR: 1.35, 95% CI: 1.04–1.75), living in a household with more than six people (aOR: 1.32, 95% CI: 1.02–1.72), and sampling during the rainy season (aOR: 1.23, 95% CI: 1.04–1.45). Individuals infected with the hookworm Necator americanus were less likely to have G. duodenalis infection (aOR: 0.71, 95% CI: 0.57–0.88).

Conclusions

Prevalence of G. duodenalis was not affected by a community WASH intervention or by two years of regular deworming with albendazole. Direct household contacts appear to play a dominant role in driving transmission. We found evidence of antagonistic effects between G. duodenalis and hookworm infection, which warrants further investigation in the context of global deworming efforts.

Trial registration Australian New Zealand Clinical Trials Registry, ACTRN12614000680662. Registered 27 June 2014, retrospectively registered. https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=366540.

Intestinal amoebiasis: 160 years of its first detection and still remains as a health problem in developing countries

Amoebiasis is a parasitic disease caused by Entamoeba histolytica (E. histolytica), an extracellular enteric protozoan. This infection mainly affects people from developing countries with limited hygiene conditions, where it is endemic. Infective cysts are transmitted by the fecal-oral route, excysting in the terminal ileum and producing invasive trophozoites (amoebae). E. histolytica mainly lives in the large intestine without causing symptoms; however, possibly as a result of so far unknown signals, the amoebae invade the mucosa and epithelium causing intestinal amoebiasis. E. histolytica possesses different mechanisms of pathogenicity for the adherence to the intestinal epithelium and for degrading extracellular matrix proteins, producing tissue lesions that progress to abscesses and a host acute inflammatory response. Much information has been obtained regarding the virulence factors, metabolism, mechanisms of pathogenicity, and the host immune response against this parasite; in addition, alternative treatments to metronidazole are continually emerging. An accesible and low-cost diagnostic method that can distinguish E. histolytica from the most nonpathogenic amoebae and an effective vaccine are necessary for protecting against amoebiasis. However, research about the disease and its prevention has been a challenge due to the relationship between E. histolytica and the host during the distinct stages of the disease is multifaceted. In this review, we analyze the interaction between the parasite, the human host, and the colon microbiota or pathogenic microorganisms, which together give rise to intestinal amoebiasis.

Intestinal parasitic infections and associated factors among mentally disabled and non-disabled primary school students, Bahir Dar, Amhara regional state, Ethiopia, 2018: a comparative cross-sectional study

Background

Intestinal parasitic infections are still common in low-income countries including Ethiopia, particularly in children due to low-quality drinking water, poor personal and environmental sanitation. Disabled individuals are excluded from most academic, economic, social and cultural opportunities, they are among the poorest and most marginalized of the whole world’s people.

The aim of this study was to assess the prevalence of intestinal parasitic infections and associated factors among mentally disabled and non-disabled students at primary schools in Bahir Dar city, Amhara regional state, Ethiopia, 2018.

Methods

A school-based Comparative cross-sectional study design was conducted from November 1–30, 2018. A total of 418 study participants, 104 mentally disabled and 314 non-disabled students were recruited through a simple random sampling technique. The collected data were coded, entered and cleaned with EpiData version 3.1 and analyzed using SPSS version 23. Multivariable logistic regression was conducted to identify factors associated with intestinal parasitic infections. The adjusted odds ratio with a 95% Confidence interval at a 5% level of significance was used to measure the strength of association.

Results

The mean age of study participants was 14.05 ± 3.66 and 11.96 ± 2.94 for mentally disabled students and non-disabled students. Prevalence of parasitic infection was 56.70% (n = 59) for mentally disabled students whereas 41.10%(n = 129) for non-disabled students. Unclean fingernails [AOR = 2.42; 1.40,4.17], health checkups [AOR = 1.87;1.16,3.02], hand washing with water only [AOR = 2.48; 1.49,4.12], cooking and sanitation source of water [AOR = 4.40;2.32,8.36], Grade [ (1–4)] [AOR = 2.27;1.41,3.67], sex [AOR = 1.64;1.03,2.63] and Family size> = 7 [AOR = 2.74;1.25,5.99] were variables which showed statistically significant association with intestinal parasitic infections.

Conclusion

The prevalence of intestinal parasitic infection was higher among mentally disabled students than non-disabled students. Unclean fingernails, health checkups, hand washing habits, source of water, family size, sex and Grade of students have had a statistically significant association with intestinal parasitic infections. Periodic medicinal treatment was needed twice a year for mentally disabled and once a year for non-disabled students.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4165-2) contains supplementary material, which is available to authorized users.

Prevalence and associated factors of intestinal parasitic infections among patients attending Shahura Health Center, Northwest Ethiopia

OBJECTIVE

Parasitic infections are the commonest infections affecting 3.5 billion people leading 450 million illnesses. Parasites are major public health problems in developing countries. This study was aimed to assess the prevalence and associated factors of parasitic infections among patients. A cross sectional study was conducted on 364 patients, attending Shahura Health Center, Northwest Ethiopia. Stool specimens were collected and examined using formol-ether concentration technique. Socio-demographic data collected using questionnaire. Binary and multivariable logistic regression analyses were conducted to calculate the strength of association between variables.

RESULT

The overall prevalence of intestinal parasitosis was 56.9%. The most prevalent parasite was Entamoeba histolytica/dispar 32.4% followed by Hookworm species 11.8% and Giardia lamblia 7.4% singly or mixed with other parasites. Furthermore, double and triple parasitic infections were observed in 3% and 1.4% patients respectively. Being male in gender (P = 0.049), age group interval between 1 and 20 years of old (P = 0.012), having stomach pain (P = 0.032) and having diarrhea (P = 0.007) were found to be significantly associated with parasitic infection. In conclusion, prevalence of parasitic infection in the area is high. Therefore, ensuring provision of clean potable water and minimizing the contamination of vegetables are recommended.

Antiamoebic drugs for treating amoebic colitis

BACKGROUND

Infection with the protozoan Entamoeba histolytica is common in low- and middle-income countries, and up to 100,000 people with severe disease die every year. Adequate therapy for amoebic colitis is necessary to reduce illness, prevent development of complicated disease and extraintestinal spread, and decrease transmission.

OBJECTIVES

To evaluate antiamoebic drugs for treating amoebic colitis.

SEARCH METHODS

We searched the available literature up to 22 March 2018. We searched the Cochrane Infectious Diseases Group Specialised Register, CENTRAL, MEDLINE, Embase, LILACS, mRCT, and conference proceedings. We contacted individual researchers, organizations, and pharmaceutical companies, and we checked reference lists.

SELECTION CRITERIA

Randomized controlled trials of antiamoebic drugs given alone or in combination, compared with placebo or another antiamoebic drug, for treating adults and children with a diagnosis of amoebic colitis.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the eligibility and methodological quality of trials and extracted and analysed the data. We calculated clinical and parasitological failure rates and rates of relapse and adverse events as risk ratios (RRs) with 95% confidence intervals (CIs), using a random-effects model. We determined statistical heterogeneity and explored possible sources of heterogeneity using subgroup analyses. We carried out sensitivity analysis by using trial quality to assess the robustness of reported results.

MAIN RESULTS

In total, 41 trials (4999 participants) met the inclusion criteria of this review. In this update, we added four trials to the 37 trials included in the first published review version. Thirty trials were published over 20 years ago. Only one trial used adequate methods of randomization and allocation concealment, was blinded, and analysed all randomized participants. Only one trial used an E histolytica stool antigen test, and two trials used amoebic culture.Tinidazole may be more effective than metronidazole for reducing clinical failure (RR 0.28, 95% CI 0.15 to 0.51; 477 participants, eight trials; low-certainty evidence) and is probably associated with fewer adverse events (RR 0.65, 95% CI 0.46 to 0.92; 477 participants, 8 trials; moderate-certainty evidence). Compared with metronidazole, combination therapy may result in fewer parasitological failures (RR 0.36, 95% CI 0.15 to 0.86; 720 participants, 3 trials; low-certainty evidence), but we are uncertain which combination is more effective than another. Evidence is insufficient to allow conclusions regarding the efficacy of other antiamoebic drugs.

AUTHORS' CONCLUSIONS

Compared with metronidazole, tinidazole may be more effective in reducing clinical failure and may be associated with fewer adverse events. Combination drug therapy may be more effective for reducing parasitological failure compared with metronidazole alone. However, these results are based mostly on small trials conducted over 20 years ago with a variety of poorly defined outcomes. Tests that detect E histolytica more accurately are needed, particularly in countries where concomitant infection with other bacteria and parasites is common.

Prevalence of intestinal parasites, with emphasis on the molecular epidemiology of Giardia duodenalis and Blastocystis sp., in the Paranaguá Bay, Brazil: a community survey

Background

Intestinal protozoan parasites are major contributors to the global burden of gastrointestinal disease causing significant socioeconomic consequences. Children living in resource-poor settings with restricted access to water and sanitary services are particularly at risk of these infections.

Methods

A prospective, community-based, cross-sectional survey was conducted in Paraná (southern Brazil) between May 2015 and May 2016. A total of 766 stool samples were individually collected from volunteers (male/female ratio: 0.99; age range: 0–76 years) and used for investigating the presence of intestinal helminth and protozoan species by routine microscopic procedures including the Kato-Katz and modified Ritchie concentration methods and the Ziehl-Neelsen stain technique. Quantitative real-time PCR confirmed microscopy-positive samples for Giardia duodenalis and the assemblages and sub-assemblages determined by multilocus sequence-based genotyping of the glutamate dehydrogenase (gdh) and β-giardin (bg) genes of the parasite. Identification of Blastocystis subtypes was carried out by amplification and sequencing of a partial fragment of the small-subunit ribosomal RNA gene (SSU rDNA) of this heterokont microorganism.

Results

Overall, 46.1% (353/766) of the participants were infected/colonised by at least one intestinal parasite/commensal species. Protozoan and helminth species were detected in 42.7% and 10.1% of the surveyed population, respectively. Blastocystis sp. (28.2%), Endolimax nana (14.9%), and Giardia duodenalis (11.0%) were the most prevalent species found among protozoans and Ascaris lumbricoides (5.0%), Trichuris trichiura (4.6%) and hookworms (1.0%) among helminths. A total of 38 G. duodenalis-positive samples were genotyped at gdh and bg markers, revealing the presence of the sub-assemblages AII (47.4%), AII/AIII (2.6%), BIII (5.3%), BIV (26.3%) and BIII/BIV (13.1%). Two samples (5.3%) were only identified as assemblage B. AII was predominantly found in females aged 5–9 years and was associated with a higher likelihood of reporting gastrointestinal symptoms. A total of 102 Blastocystis-positive samples were successfully subtyped at the SSU rRNA gene revealing the presence of ST1 (36.3%), ST2 (15.7%), ST3 (41.2%), ST4 (2.9%), ST6 (1.0%) and ST8 (2.9%).

Conclusions

Data presented here indicate that enteric parasites still represent a pressing health concern in Paraná, Brazil, probably due to sub-optimal water, sanitation and hygiene conditions. A mostly anthroponotic origin is suspected for G. duodenalis and Blastocystis sp. infections.

Electronic supplementary material

The online version of this article (10.1186/s13071-018-3054-7) contains supplementary material, which is available to authorized users.

Prevalence and risk factors for intestinal parasitic infections in pregnant women residing in three districts of Bogotá, Colombia

BACKGROUND

Intestinal parasitic infections (IPI) lead to significant morbidity and mortality in pediatric and adult populations worldwide. Intestinal parasitism during pregnancy is of interest as it may affect the health of pregnant women and their offspring. This study determined the prevalence of IPI in pregnant women living in substandard conditions in three urban districts of Bogotá, Colombia. Associations between prevalence and sociodemographic factors, housing, and living conditions were also evaluated.

METHODS

In a cross-sectional and community-based study, pregnant women were recruited from three districts of Bogotá. A total of 550 participants answered a questionnaire; 331 of these also provided stool samples, with 233 providing one and 98 providing two stool samples. Questionnaire responses were associated with the presence of intestinal parasites, which was determined using a standard combined microscopy technique including direct wet mount and formol-ether concentration. Results were verified by supplementary examination of 48 stool samples by quantitative polymerase chain reaction (qPCR).

RESULTS

Among pregnant women who lived in selected poor residential areas in Bogotá, the overall prevalence of intestinal parasitism was 41% with 9% polyparasitism. Pathogenic parasites were present in 1.2% of the 331 participants including Giardia lamblia and Ascaris lumbricoides. Higher prevalence was found for parasites with debated pathogenicity, including Blastocystis hominis (25%), Endolimax nana (15%), Entamoeba coli (8%), and Iodamoeba butschlii (2%). Entamoeba histolytica/dispar complex was also detected (1.5%). When comparing a subset of stool samples using the combined microscopy technique and qPCR, the latter detected a higher 58.3% overall IPI prevalence. Higher prevalence of infections by any intestinal parasite was found in participants who had never been dewormed (p = 0.01). Higher but not statistically significant associations were found between any parasite and women living with a partner, and intestinal polyparasitism and being from a minority group and not having a water sink.

CONCLUSIONS

This first study of the prevalence of intestinal parasitism in Bogotá focused on pregnant women living in poverty, found a high prevalence of intestinal parasites of debated pathogenicity, and confirmed a low prevalence of pathogenic intestinal parasites. These results highlight the need for educational interventions to disrupt transmission routes for prevalent parasites.

Undernutrition, intestinal parasitic infection and associated risk factors among selected primary school children in Bahir Dar, Ethiopia

Background

Monitoring of undernutrition and parasitic infection are essential to design appropriate intervention strategies. The aim of this study was to assess the prevalence of undernutrition, intestinal parasitic infection and their associated risk factors among school children in Bahir Dar, Ethiopia.

Methods

A school-based cross-sectional survey was conducted from February to June 2014 among 382 students selected from primary schools in Bahir Dar. The study subjects were selected by a systematic random sampling method. Sociodemographic data from students and their family/guardians were obtained using structured questionnaire. Height and weight of the students were measured using a standard calibrated balance. Fresh fecal samples were collected and processed using formalin-ether concentration technique. The data were analyzed using SPSS version 20.0 statistical software.

Results

The overall prevalence of undernutrition was 41.6% (18.3% stunted, 26.7% thinness and 25.9% underweight). Meal frequency ≤ 3 times a day (AOR=4.11; 95% CI: 2.23–7.59) and family monthly income <500 birr (AOR=5.87; 95% CI: 2.61–13.23) were important predictors of undernutrition. The risk of stunting was increased among students with meal frequency ≤ 3 times a day (AOR=5.56; 95% CI: 2.97–10.41) and age ranges from 9-10 years (AOR=3.02; 95% CI: 1.41–6.47). The odds of thinness was significantly increased among students with parasitic infection (AOR=1.92; 95% CI: 1.15–3.19) and family monthly income <1500 birr (AOR=2.69; 95% CI: 1.16–6.26). The likelihood of being underweight was increased among students infected with intestinal parasites (AOR=2.43; 95% CI: 1.40–4.22). The overall prevalence of intestinal parasitosis was 52.4%. The risk of parasitic infection was significantly increased among students with unclean fingernails (AOR=4.96; 95% CI: 2.79–8.82) and irregular hand washing habit (AOR=8.05; 95% CI: 4.66–13.89).

Conclusions

This study revealed that undernutrition and intestinal parasitic infection were public health problems among school children in the study areas. These results highlight the importance for integrated efforts to address undernutrition and parasitic infection.

Epidemiology of intestinal parasite infections in three departments of south-central Côte d'Ivoire before the implementation of a cluster-randomised trial

Hundreds of millions of people are infected with helminths and intestinal protozoa, particularly children in low- and middle-income countries. Preventive chemotherapy is the main strategy to control helminthiases. However, rapid re-infection occurs in settings where there is a lack of clean water, sanitation and hygiene. In August and September 2014, we conducted a cross-sectional epidemiological survey in 56 communities of three departments of south-central Côte d'Ivoire. Study participants were invited to provide stool and urine samples. Stool samples were examined for helminth and intestinal protozoa infections using the Kato-Katz technique and a formalin-ether concentration method. Urine samples were subjected to a filtration method for the diagnosis of Schistosoma haematobium. Information on sociodemographic characteristics, knowledge, attitude, practices and beliefs with regard to hygiene, sanitation and intestinal parasitic diseases were collected using a questionnaire administered to household heads. Multivariable logistic regression models were employed to analyse associations between parasite infections and risk factors. Overall, 4,305 participants had complete parasitological and questionnaire data. Hookworm was the predominant helminth species (21.2%), while Ascaris lumbricoides, Trichuris trichiura, Schistosoma mansoni and S. haematobium showed prevalences below 10%. Infections with pathogenic intestinal protozoa (e.g. Entamoeba histolytica/E. dispar and Giardia intestinalis) were similarly prevalent in the three departments. Hookworm infection was associated with open defecation and participants' age and sex. Entamoeba coli infection was negatively associated with the use of tap water at home (odds ratio (OR) = 0.66; p = 0.032). Disposal of garbage in close proximity to people's home was positively associated with G. intestinalis (OR = 1.30; p = 0.015). Taken together, helminth and intestinal protozoa infections affected a considerable proportion of rural dwellers in south-central Côte d'Ivoire at the onset of a cluster-randomised intervention trial. Our results will serve as baseline to monitor the effect of a package of interventions, including preventive chemotherapy, sanitation and health education on re-infection with helminths and intestinal protozoa.

TRIAL REGISTRATION

ISRCTN53102033 (date assigned: 26 March 2014).

Intestinal symptoms and Blastocystis load in schoolchildren of Paranaguá Bay, Paraná, Brazil

The symptomatology of Blastocystis cannot be attributed to any particular subtype, although can be related to a high Blastocystis infection load. One stool sample from each of 217 schoolchildren of Vale de Sol Paranaguá Bay (Paraná, Brazil) was collected. Three milliliters of each fixed stool sample were processed applying the formalin-ether concentration technique. After obtaining the overall prevalence of intestinal parasites, quantification was carried out in Blastocystis positive samples. A total of 75/217 (34.6%) children suffered from intestinal symptoms (abdominal pain and/or persistent diarrhea), of whom 41.3% (31/75) presented moderate/heavy Blastocystis load with a statistically significant risk to present intestinal symptoms (OR 0.039 [0.006-0.15]; p<0.001) Moreover, those symptomatic schoolchildren monoparasitized only by Blastocystis (10/75, 13.3%), and those polyparasitized by Blastocystis with other non-pathogenic species (15/75, 20%) with moderate/heavy loads, also entail a statistically significant risk of intestinal symptomatology, both in monoparasitism (12%, OR 0.10 [0.004-0.63]; p=0.021) and in polyparasitism with a non-pathogenic parasite (18.6%, OR 0.059 [0.002-0.35]; p=0.001). For the first time in Brazil, using data from schoolchildren of Paranaguá Bay, we demonstrated that moderate/ heavy loads of Blastocystis could be related to intestinal symptoms.

Stimulated and Unstimulated Saliva Levels of Calcium and Magnesium in Giardiasis

Giardia lamblia causes malabsorption. The aim of this study was to evaluate serum and saliva calcium and magnesium levels in patients with giardiasis. Thirty patients with giardiasis as a case and 30 person without giardiasis as a control group were enrolled. The stimulated and unstimulated whole saliva and serum calcium and magnesium levels were assayed by Arsenazo reaction and xylidyl blue complex methods, respectively. Mean calcium and magnesium level was low in serum and stimulated saliva of case group than that of controls. However, they were higher in the unstimulated saliva of the case group. It is suggested that patients suffering from giardiasis have low calcium and magnesium levels, and they lose the most of calcium and magnesium by saliva during unstimulated condition.

Prevalence of intestinal parasitic infections and associated risk factors among students at Dona Berber primary school, Bahir Dar, Ethiopia

BACKGROUND

Intestinal parasitic infections are still one of the major health concerns in developing countries. Monitoring of intestinal parasitic infection and associated risk factors are essential for intervention strategies. Therefore, the aim of this study was to assess the prevalence of intestinal parasitic infection and associated risk factors among students at Dona Berber primary school, Bahir Dar, Ethiopia.

METHODS

School based cross-sectional study was conducted among students at Dona Berber primary school from October 2015 to June 2016. Three hundred fifty nine students were involved in the study by providing stool specimens and detailed personal information. Students were selected by stratified and systematic random sampling method. Fresh stool samples were collected from each student and processed by formal-ether fecal concentration technique. Data were analyzed using SPSS version 20.0 statistical software and p value <0.05 were used as statistically significant.

RESULTS

Among the 359 students participated in the study, 235 (65.5%) were infected by one or more intestinal parasites. The rates of single and double parasitic infections among students were 49.6% and 16.2%, respectively. The most prevalent parasite detected in the study was E. histolytica/dispar (24.5%) followed by hookworm (22.8%). Among the different variables assessed in the study, family size of 6 (AOR = 4.90; 95% CI, 2.03-11.83), irregularly shoe wearing habit (AOR = 2.85; 95% CI, 1.53-5.32) and unclean finger nail (AOR = 3.68; 95% CI, 1.87-7.26) were independently predict intestinal parasitic infections. Student drinking well water (AOR = 2.51; 95% CI, 2.30-4.86) and unclean finger nail (AOR = 4.42; 95% CI, 2.55-7.65) were strongly associated with E. histolytica/dispar infection. Likewise, irregular shoe wearing habit (AOR = 14.13; 95% CI, 7.06-28.29) was strongly associated with hookworm infections.

CONCLUSION

High prevalence of intestinal parasitic infection among the study participants demands improvement of health education, environmental sanitation and quality of water sources.

Children with moderate-high infection with Entamoeba coli have higher percentage of body and abdominal fat than non-infected children

BACKGROUND

Intestinal parasites, virus and bacterial infections are positively associated with obesity and adiposity in vitro and in animal models, but conclusive evidence of this relationship in humans is lacking. The aim of this cross-sectional study was to determine differences in adiposity between infected and non-infected children, with a high prevalence of intestinal parasitic infection and obesity.

SUBJECTS

A total of 296 school-aged children (8.0 ± 1.5 years) from a rural area in Querétaro, Mexico, participated in this study. Anthropometry (weight, height and waist circumference) and body fat (DXA) were measured in all children. A fresh stool sample was collected from each child and analysed for parasites. Questionnaires related to socioeconomic status and clinical history were completed by caretakers.

RESULTS

Approximately 11% of the children were obese, and 19% were overweight. The overall prevalence of infection was 61%. Ascaris lumbricoides was the most prevalent soil transmitted helminth (16%) followed by hookworm. Entamoeba coli was the predominant protozoa (20%) followed by Endolimax nana, Balantidium coli, Entamoeba histolytica/dispar, Iodamoeba bütschlii and Giardia lamblia. Children with moderate-heavy infection of E. coli had significantly higher waist circumference, waist-to-height ratio, body and abdominal fat than children not infected or with light-intensity infection (p < 0.05).

CONCLUSION

These findings raise the possibility that a moderate or heavy infection with E. coli may contribute to fat deposition and thereby have long-term consequences on human health. Further studies are needed to better understand if E. coli contributes directly to fat deposition and possible mechanisms.

Combination therapy in the management of giardiasis: What laboratory and clinical studies tell us, so far

Treatment failures in patients suffering from giardiasis are not uncommon feature. The most frequent approach in these cases is to treat these patients with longer repeated courses and/or higher doses of the primary therapy, or using drugs from a different class to avoid potential cross-resistance. However, a higher rate of adverse events may limit this strategy. In this context, combination therapy (CT) is emerging as a valuable option against refractory giardiasis. In the attempt to evaluate the benefits of CT, a number of experimental studies, clinical series, and randomized clinical trials (RCTs), as well as several veterinary studies have been performed, with varying results. Here, we present a critical analysis of the available information regarding CT for the treatment of Giardia infection, as well as the authors' opinion with respect to its use. RCTs of combination therapy are limited and the optimal combinations and administration strategies need yet to be clarified. Analyses of the cost-effectiveness and RCTs of CTs for Giardia infection are required to assess the role of these drugs for the control of giardiasis, mainly in the case of treatment failures linked to suspected drug tolerance are the case.

Prevalence of Giardiaduodenalis among children from a central region of Cuba: molecular characterization and associated risk factors

Giardia duodenalis is one of the most frequent intestinal parasitic infections in children worldwide. To date, eight main assemblages of G. duodenalis have been described, but only A and B genetic groups are known to infect humans. A cross-sectional study was conducted to determine the prevalence and risk factors of Giardia duodenalis infection in 417 preschool children from the Fomento municipality in the central region of Cuba between January and June 2013. The overall prevalence of Giardia infection was 10.79 %. Assemblage identification was carried out by the amplification of a fragment of the triose phosphate isomerase (tpi) gene. DNA from 36 of 45 (80 %) samples was successfully amplified by PCR-tpi. Assemblage B and mixed assemblages A + B represented 52.78 and 36.11 % respectively, of genotyped samples. Assemblage A accounts for only 11.11 %. Children who were cared for at home were associated with diarrhea caused by assemblage B. No associations were found between other clinical variables with infecting assemblage of Giardia. Univariate analysis identified the use of unsafe water resources (OR 2.9; CI 1.2-6.8) and-even more interestingly-keeping dogs indoor (OR 2.5; CI 1.2-5.4) were significant risk factors associated with Giardia infection among children. Multivariate analysis using introduction test logistic regression ratified the association of these two risk factors: kept dogs indoor (OR 2.8, CI 1.1-5.3), and untreated water (OR 1.4, CI 1.4-4.9) with Giardia infection. This information may be useful for an effective prevention and control programme of giardiasis in this population.

Impact of co-infections with enteric pathogens on children suffering from acute diarrhea in southwest China

Background

Acute diarrhea is a global health problem, resulting in high morbidity and mortality in children. It has been suggested that enteric pathogen co-infections play an important role in gastroenteritis, but most research efforts have only focused on a small range of species belonging to a few pathogen groups. This study aimed to assess the impact of co-infections with a broad range of enteric pathogens on children aged below five years who suffer from acute diarrhea in southwest China.

Method

A total of 1020 subjects (850 diarrhea cases and 170 healthy controls) were selected from four sentinel hospitals in Kunming, Yunnan province, southwest China, from June 2014 to July 2015. Stool specimens were collected to detect five virus (rotavirus group A, RVA; norovirus, NoV; Sapovirus, SaV; astrovirus, As; and adenovirus, Ad), seven bacterial (diarrheagenic Escherichia coli, DEC; non-typhoidal Salmonella, NTS; Shigella spp.; Vibrio cholera; Vibrio parahaemolyticus; Aeromonas spp.; and Plesiomonas spp.), and three protozoan (Cryptosporidium spp., Giardia lamblia, and Blastocystis hominis, B. hominis) species using standard microbiologic and molecular methods. Data were analyzed using the partial least square regression technique and chi-square test.

Results

At least one enteric pathogen was detected in 46.7 % (n = 397) of acute gastroenteritis cases and 13.5 % (n = 23) of healthy controls (χ² = 64.4, P < 0.05). Single infection with RVA was associated with acute diarrhea (26.5 % vs. 5.8 %, P < 0.05). The prevalence of a single infection with B. hominis in diarrhea cases was higher than in healthy controls (3.1 % vs. 0.5 %, OR = 4.7, 95 % CI: 1.01–112.0). Single infection with NoV GII was not associated with diarrhea (4.4 % vs. 3.5 %, OR = 1.2, 95 % CI: 0.5–3.3). Single infections with bacterial species were not observed. The prevalence of co-infections with two enteric pathogens in diarrhea cases was higher than in asymptomatic children (20.1 % vs. 5.3 %, P < 0.05). RVA-NoV GII was the most common co-infection in symptomatic children (4.4 %), with it aggravating the severity of diarrhea.

Conclusions

Although it is clear that RVA has an overwhelming impact on diarrhea illnesses in children, co-infection with other enteric pathogens appears to also aggravate diarrhea severity. These findings should serve as evidence for public health services when planning and developing intervention programs.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-016-0157-2) contains supplementary material, which is available to authorized users.

Current status of Blastocystis: A personal view

Despite Blastocystis being one of the most widespread and prevalent intestinal eukaryotes, its role in health and disease remains elusive. DNA-based detection methods have led to a recognition that the organism is much more common than previously thought, at least in some geographic regions and some groups of individuals. Molecular methods have also enabled us to start categorizing the vast genetic heterogeneity that exists among Blastocystis isolates, wherein the key to potential differences in the clinical outcome of Blastocystis carriage may lie. In this review we summarize some of the recent developments and advances in Blastocystis research, including updates on diagnostic methods, molecular epidemiology, genetic diversity, host specificity, clinical significance, taxonomy, and genomics. As we are now in the microbiome era, we also review some of the steps taken towards understanding the place of Blastocystis in the intestinal microbiota.

Prevalence of Intestinal Parasitic Infections in Jiroft, Kerman Province, Iran

BACKGROUND

Intestinal parasitic infections have a worldwide distribution. High prevalence of intestinal parasitic infections in individuals with low socioeconomic status and environmental conditions was found. No study has ever been conducted on the prevalence of these infections in Jiroft. Therefore, in this study prevalence of intestinal parasitic infections was evaluated in Jiroft, Kerman Province, Iran.

METHODS

A total of 1060 individuals from rural and urban areas of Jiroft were sampled accidentally, during 2013-2014. Fresh stool samples were collected from all individuals and examined by formalin ether concentration and agar plate culture. Direct examination was performed on watery samples.

RESULTS

Out of 1060 individuals, 563 (53.1%) and 497 (46.9%) people were from rural and urban areas, respectively. In general, 297 individuals (28%) were infected with intestinal parasites. The prevalence of infection for protozoa and helminthes infections were 27.4% and 1.8%, respectively. The most prevalent protozoans were Blastocystis hominis (13.7%) and Giardia lamblia (7.8%), and that of helminth was Hymenolepis nana (1.1%).

CONCLUSION

Intestinal protozoan parasites were more prevalent than helminth parasites. Source of water supply and personal hygiene were important factors in the distribution of parasites in the study area.

Effect of sanitation and water treatment on intestinal protozoa infection: a systematic review and meta-analysis

BACKGROUND

Pathogenic intestinal protozoa infections are responsible for substantial mortality and morbidity, particularly in settings where people lack improved sanitation and safe drinking water. We assessed the relation between access to, and use of, sanitation facilities and water treatment and infection with intestinal protozoa.

METHODS

We did a systematic review and searched PubMed, ISI Web of Science, and Embase from inception to June 30, 2014, without restrictions on language. All publications were examined by two independent reviewers and were included if they presented data at the individual level about access or use of sanitation facilities or water treatment, in combination with individual-level data on human intestinal protozoa infections. Meta-analyses using random effects models were used to calculate overall estimates.

FINDINGS

54 studies were included and odds ratios (ORs) extracted or calculated from 2 × 2 contingency tables. The availability or use of sanitation facilities was associated with significantly lower odds of infection with Entamoeba histolytica or Entamoeba dispar (OR 0·56, 95% CI 0·42-0·74) and Giardia intestinalis (0·64, 0·51-0·81), but not for Blastocystis hominis (1·03, 0·87-1·23), and Cryptosporidium spp (0·68, 0·17-2·68). Water treatment was associated with significantly lower odds of B hominis (0·52, 0·34-0·78), E histolytica or E dispar (0·61, 0·38-0·99), G intestinalis (0·63, 0·50-0·80), and Cryptosporidium spp infections (0·83, 0·70-0·98).

INTERPRETATION

Availability and use of sanitation facilities and water treatment is associated with lower odds of intestinal protozoa infections. Interventions that focus on water and sanitation, coupled with hygiene behaviour, should be emphasised to sustain the control of intestinal protozoa infections.

FUNDING

Swiss National Science Foundation (project numbers PBBSP3-146869 and P300P3-154634), Medicor Foundation, European Research Council (614739-A_HERO).

Repurposing drugs for the treatment and control of helminth infections

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Drug repurposing continues to be the central drug discovery strategy for helminths.

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Most repurposed drugs come from veterinary medicine and known drug classes.

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Only a handful of drugs have advanced clinically.

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More collaborations and funding are needed to advance discoveries to the market.

Helminth infections are responsible for a considerable public health burden, yet the current drug armamentarium is small. Given the high cost of drug discovery and development, the high failure rates and the long duration to develop novel treatments, drug repurposing circumvents these obstacles by finding new uses for compounds other than those they were initially intended to treat. In the present review, we summarize in vivo and clinical trial findings testing clinical candidates and marketed drugs against schistosomes, food-borne trematodes, soil-transmitted helminths, Strongyloides stercoralis, the major human filariases lymphatic filariasis and onchocerciasis, taeniasis, neurocysticercosis and echinococcosis. While expanding the applications of broad-spectrum or veterinary anthelmintics continues to fuel alternative treatment options, antimalarials, antibiotics, antiprotozoals and anticancer agents appear to be producing fruitful results as well. The trematodes and nematodes continue to be most investigated, while cestodal drug discovery will need to be accelerated. The most clinically advanced drug candidates include the artemisinins and mefloquine against schistosomiasis, tribendimidine against liver flukes, oxantel pamoate against trichuriasis, and doxycycline against filariasis. Preclinical studies indicate a handful of promising future candidates, and are beginning to elucidate the broad-spectrum activity of some currently used anthelmintics. Challenges and opportunities are further discussed.

School-Based Intervention: Evaluating the role of Water, Latrines and Hygiene Education on Trachoma and Intestinal Parasitic Infections in Ethiopia

OBJECTIVE

We sought to evaluate the impact of a hygiene and sanitation intervention program among school-children to control active trachoma and intestinal parasitic infections.

METHODS

This longitudinal epidemiologic study was conducted among 630 students in rural Ethiopia. Baseline and follow-up surveys were conducted to evaluate the impact of a three pronged intervention program i) constructing of ventilated improved pit latrines, ii) provision of clean drinking water, and iii) and hygiene education. Socio-demographic information was collected using a structured questionnaire. Presence of trachoma and intestinal parasitic infections were evaluated using standard procedures.

RESULTS

At baseline 15% of students had active trachoma while 6.7% of them were found to have active trachoma post intervention (p<0.001). Similar improvements were noted for parasitic infections. At baseline 7% of students were reported to have helminthic infections and 30.2% protozoa infections. However, only 4% of students had any helminthic infection and 13.4% (p<0.001) of them were found to have any protozoa infection. Improvements were noted in students' knowledge and attitudes towards hygiene and sanitation.

CONCLUSIONS

The results of our study demonstrated that provision of comprehensive and targeted sanitation intervention program was successful in reducing the burden of trachoma and intestinal parasitic infection among school children.

Comparison of the Kato-Katz method and ether-concentration technique for the diagnosis of soil-transmitted helminth infections in the framework of a randomised controlled trial

Soil-transmitted helminth infections are a major public health problem. An accurate diagnosis is important in order to identify individuals and communities in need of intervention, and for monitoring drug efficacy and potential emergence of resistance. We compared the accuracy of the Kato-Katz method and ether-concentration technique for the diagnosis of soil-transmitted helminth infections within a randomised controlled trial. Quadruplicate Kato-Katz thick smears (duplicate Kato-Katz from two stool samples each) were examined before (baseline) and 3 weeks after treatment (follow-up). Additionally, at baseline and follow-up, the first stool sample was subjected to an ether-concentration method. We determined the prevalence, sensitivity, negative predictive value, diagnostic agreement and cure rates for single and duplicate Kato-Katz thick smears from the first stool sample, quadruplicate Kato-Katz thick smears produced from two stool samples and single ether-concentration as compared to our 'gold' standard (i.e. quadruplicate Kato-Katz plus ether-concentration). Quadruplicate Kato-Katz revealed a higher sensitivity than single ether-concentration for Trichuris trichiura at baseline (94.3 % vs. 88.5 %, p = 0.002) and follow-up (93.8 % vs. 83.5 %, p < 0.001). In contrary, at follow-up, ether-concentration showed a higher sensitivity than quadruplicate Kato-Katz for Ascaris lumbricoides diagnosis (86.7 % vs. 46.7 %, p = 0.012). The ether-concentration method showed similar or slightly higher sensitivity than the Kato-Katz technique based on a single stool sample for all soil-transmitted helminth infections. The estimated cure rates were heavily dependent on the diagnostic technique and sampling effort. In conclusion, data on the prevalence of soil-transmitted helminth infections and the efficacy of anthelminthics are greatly influenced by the diagnostic method and sampling effort. The ether-concentration technique is a valuable alternative to the Kato-Katz method for helminth diagnosis.

Breast-feeding protects infantile diarrhea caused by intestinal protozoan infections

This study investigated the effect of breast-feeding in protection against protozoan infection in infants with persistent diarrhea. Infants were classified into 2 groups; 161 breast-fed infants and the same number of non-breast-fed infants. Microscopic examinations of stool were done for detection of parasites and measuring the intensity of infection. Moreover, serum levels of IgE and TNF-α were measured by ELISA. Cryptosporidium spp., Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Blastocystis sp. were demonstrated in infants with persistent diarrhea. The percentage of protozoan infections was significantly lower in breast-fed infants than that in the non-breast-fed infants. The levels of IgE and TNF-α were significantly lower in the breast-fed group than in the non-breast-fed group. There were significant positive associations between the serum levels of IgE and TNF-α and the intensity of parasite infection in the breast-fed group. It is suggested that breast-feeding has an attenuating effect on the rate and intensity of parasite infection.