Prevalence of Soil-Transmitted Helminthes and Associated Risk Factors Among People of Ethiopia: A Systematic Review and Meta-Analysis

Efficacy of albendazole against soil-transmitted helminth infections in Ethiopia: a systematic review and meta-analysis

Soil-transmitted helminths (STH) are neglected parasites more prevalent in the tropics. Periodic mass distribution of albendazole, is one key strategy to control STHI in endemic areas. However, benzimidazoles have low efficacy against STHI, and there is a lack of information on the magnitude of the problem in Ethiopia. Articles were searched from PubMed using MeSH words, Google Scholar, Web of science, EMBASE and Scopus database to retrieve the data published and available until December 30, 2022. Totally, 107 published articles were retrieved. Only studies conducted in English that reported the efficacy of albendazole against STHI in any year and studies with more than fifty positive cases were included in the present study. The efficacy of albendazole was estimated by its cure rate and egg reduction rate. Excel software was used to extract the name of the authors, the total sample size, number of cured participants, treatment assessment time, STH parasite involved, the study area, and the year of publication. The pooled efficacy of albendazole against STHs was analyzed using comprehensive meta-analysis version 2.2 software. A total of 14 studies (13 for hookworm, 12 for Ascaris lumbricoides, and 12 for Trichuris trichiura) fulfilled the inclusion criteria for the present systematic review and meta-analysis. The total positives for hookworm, A. lumbricoides, and T. trichiura were 1253 (24.9%), 1570 (29.5%), and 1647 (30.6%), respectively. The overall pooled efficacy of albendazole was 92.2% (95% CI 86.2-98.9%) against hookworm, 97.7% (95% CI 96.3-98.6%) against A. lumbricoides, and 38.6% (95% CI 31.0-46.9%) against T. trichiura. In subgroup analysis, the efficacy of albendazole against hookworm was 93.4% (95% CI 85.1-97.2%) in Oromia, 96.7% (95% CI 93.8-98.2%) in Sidama, and 77.2% (95% CI 64.4-86.4%) in Amhara region. Its heterogeneity was high (I2 = 89.418). The efficacy of albendazole against A. lumbricoides was 98.3% (95% CI 97.0-99.0%) in Oromia and 96.63% (95% CI 93.2-98.3%) in Sidama region. Its heterogeneity was moderate (I2 = 41.5%). Albendazole efficacy against T. trichiura was 39.0% (95% CI 30.4-48.5%) in Oromia and 37.8% (95% CI 21.8-56.9%) in Sidama region with high heterogeneity (I2 = 90.6%). In the present review, albendazole is effective against hookworm and A. lumbricoides but less effective against T. trichiura. Albendazole should therefore be used as a treatment option in hookworm and A. lumbricoides endemic areas. However, alternative drugs should be sought for T. trichiura.

Prevalence and risk factors of soil transmitted helminths among vegetable farmers of Akaki river bank, Addis Ababa, Ethiopia

BACKGROUND

In Ethiopia, 79 million people live in soil transmitted helminths endemic areas. The Ethiopia established a National goal to eradicate STH transmission by 2025. To meet that goal, it is imperative that data is acquired on community helminth infection risk. This study examined the prevalence of STH and risk factors for infection in vegetable farmers working on Akaki River Bank, Addis Ababa, Ethiopia.

METHODS

A cross-sectional study was conducted between November 7, 2022, and June 2023. A stratified random sampling was used to select farming households. Two hundred and sixteen farmers were enrolled in the study. Data on socio-demographic, WASH, wastewater irrigation related factors were collected by trained data collectors using a structured questionnaire. Kato-Katz concentration was utilized to detect STH. The data were entered using EpiData 3.1 and analyzed with Stata 14.0, using p-values less than 0.05 to identify significant factors. Logistic regression was used to identify independent risk factors for infection.

RESULTS

The prevalence of STH was 22.2% (95% CI = 13.6-27.9%), with Ascaris lumbricoides being the most common (11.1%), followed by hookworm (7.4%), and Trichuris trichiura (3.7%). Low income levels (AOR = 1.85, 95% CI = 1.25-5.99), lack of handwashing before eating (AOR = 2.25, 95% CI = 1.58 - 11.3), absence of fingernails cleanliness (AOR = 1.97, 95% CI = 1.74-39.5), not wearing shoes at work (AOR = 3.4, 95% CI = 2.98-82.2), touching the face with dirty hands (AOR = 2.9, 95% CI = 0.68-28.2), washing vegetables with irrigation wastewater (AOR = 2.1, 95% CI = 1.95-45.2), and not wearing protective clothing during farming activities (AOR = 2.99, 95% CI = 1.58 - 22.4) were the significant risk factors for infection with STH.

CONCLUSION

Of the farming communities examined in this study, one of the five was found to be infected with soil transmitted helminth. This research has shown clear risk factors for STH infection including: lack of personal hygiene practices, insufficient sanitation access, and limited use of protective equipment. To achieve the national goal, there is a need for farming communities to understand preventative risks of infection, improve WASH (Water access, sanitation and hygine) practices, WASH access, protective equipment, and health education.

Efficacy of Albendazole and Mebendazole Against Soil Transmitted Infections among Pre-School and School Age Children: A Systematic Review and Meta-Analysis

BACKGROUND

Soil-transmitted helminthic (STH) infections are the leading cause of stunting among children. To lessen the burden, the World Health Organization (WHO) recommended a periodic deworming program through the use of single-dose therapy in the endemic regions. Therefore, the purpose of this study was to synthesize evidence about the efficacy of anthelminthic drugs against STH infections among preschool and school-age children.

METHODS

The Preferred Reposting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria were followed in this study. Relevant electronic databases, including PubMed, Scopus, Embase, DOAJ, Science Direct, the WHO Clinical Trials.gov library, Google Scholar, and AJOL databases, were searched for relevant publications. Randomized controlled trials (RCTs) and non-randomized interventional studies focused on the efficacy of albendazole and mebendazole against STHs in children were included in the study. Review Manager was used to analyze the data. A random effects model was used to obtain the pooled estimated efficacy. To evaluate heterogeneity, the I2 test and Cochrane Q (χ2) were employed. The risk of publication bias was investigated using Egger's test and the funnel plot. The protocol of this review was registered at the PROSPERO international prospective register of systematic reviews (CRD42023401196).

RESULTS

Of the 69 publications selected for the systematic review, 66 with complete data were included in the meta-analysis. Single doses of albendazole and mebendazole have shown satisfactory efficacy [egg reduction rate (ERR)] against Ascaris lumbricoides [95.54% (95% CI: 88.75-102.34%) and 98.69% (95% CI: 97.68-99.65%), respectively. The effectiveness of these two drugs against Trichuris trichiura and hookworms was comparatively low (< 80% ERR), except for albendazole, which showed high ERRs [93.44% (95%CI: 92.39-94.49%)] against hookworms. The cure rate (CR) of albendazole against T. trichiura, A. lumbricoides, and hookworms were 50.8%, 91.3%, and 78.32%, respectively. Likewise, mebendazole showed CRs of 48.15%, 92.8%, and 49.32% against T. trichiura, A. lumbricoides, and hookworms, respectively. Subgroups such as studies conducted after 2000, diagnostic type (McMaster), and longer follow-up weeks significantly reduced the efficacy of the two drugs against T. trichura. While the combination of albendazole or mebendazole with other drugs and RCT showed significantly improved efficacy against T. trichura. The count of eggs per gram of stool (EPG) was identified as one of the variables that negatively and significantly influenced the efficacy of albendazole or mebendazole against A. lumbricoides.

CONCLUSION

Despite the wide range of ERRs and CR reported in the different articles included in this review, the pooled estimated efficacy of albendazole and mebendazole against STHs falls in the satisfactory category of WHO recommendations. Further evaluation of the combination of anthelminthic drugs as a preventive chemotherapy option and routine drug efficacy testing are necessary to prevent the emergence and widespread use of drug-resistant STHs.

Prevalence and Determinants of Geohelminthiasis among School-Age Children in Jimma City, Ethiopia

School-age children (SAC) are at a higher risk of geohelminth or soil-transmitted helminth (STH) infections due to their practice of walking and playing barefoot, lack of adequate sanitary facilities, and poor personal hygiene. In Ethiopia, periodic deworming has been implemented since 2013 with the aim of interrupting the transmission of STH in children by 2025. To evaluate the likely success of such a control program, it is crucial to monitor the transmission of STH, especially in peri-urban settings where environmental sanitation is modest. The aim of this study was to determine the prevalence and determinants of STH infections among SAC in peri-urban areas of Jimma City, Southwestern Ethiopia. A community-based cross-sectional study was conducted in five peri-urban Kebeles of Jimma City from July to September, 2021. Systematic random sampling was used to select 522 households with at least one child, and 478 children (5-15 years old) were recruited randomly from the households. Data on sociodemographic and potential risk factors were collected using a structured questionnaire. Stool samples from each study participant were collected and examined microscopically using the Kato-Katz technique. Multivariate logistic regression model was used to identify risk factors associated with STH infections. The prevalence of any STH among SAC was 23.4%, with Ascaris lumbricoides being the predominant STH species (15.7%), followed by Trichuris trichiura (9%) and hookworm (2.1%). Most (86.6%) of the STH-positive SAC had a single infection and a light infection intensity (88.2%), with a mean intensity of 367.4 eggs per gram. Location of Kebele (AOR = 2.73; 95% CI: 1.21-6.16, p=0.016), lack of hand washing after defecation (AOR = 6.39; 95% CI: 3.16-12.95, p < 0.001), untrimmed fingernails (AOR = 2.65; 95% CI: 1.56-4.51, p < 0.001), and lack of previous deworming (AOR = 2.90; 95% CI: 1.47-5.74, p=0.002) were significant predictors for STH infections among SAC. In conclusion, the study revealed that STH infections are significant health problem in the peri-urban areas of Jimma City. Strengthening periodic deworming and improving children's hygiene through health education are required to reduce the transmission.

Soil-transmitted helminths: A critical review of the impact of co-infections and implications for control and elimination

Researchers have raised the possibility that soil-transmitted helminth (STH) infections might modify the host's immune response against other systemic infections. STH infections can alter the immune response towards type 2 immunity that could then affect the likelihood and severity of other illnesses. However, the importance of co-infections is not completely understood, and the impact and direction of their effects vary considerably by infection. This review synthesizes evidence regarding the relevance of STH co-infections, the potential mechanisms that explain their effects, and how they might affect control and elimination efforts. According to the literature reviewed, there are both positive and negative effects associated with STH infections on other diseases such as malaria, human immunodeficiency virus (HIV), tuberculosis, gestational anemia, pediatric anemia, neglected tropical diseases (NTDs) like lymphatic filariasis, onchocerciasis, schistosomiasis, and trachoma, as well as Coronavirus Disease 2019 (COVID-19) and human papillomavirus (HPV). Studies typically describe how STHs can affect the immune system and promote increased susceptibility, survival, and persistence of the infection in the host by causing a TH2-dominated immune response. The co-infection of STH with other diseases has important implications for the development of treatment and control strategies. Eliminating parasites from a human host can be more challenging because the TH2-dominated immune response induced by STH infection can suppress the TH1 immune response required to control other infections, resulting in an increased pathogen load and more severe disease. Preventive chemotherapy and treatment are currently the most common approaches used for the control of STH infections, but these approaches alone may not be adequate to achieve elimination goals. Based on the conclusions drawn from this review, integrated approaches that combine drug administration with water, sanitation and hygiene (WASH) interventions, hygiene education, community engagement, and vaccines are most likely to succeed in interrupting the transmission of STH co-infections. Gaining a better understanding of the behavior and relevance of STH co-infections in the context of elimination efforts is an important intermediate step toward reducing the associated burden of disease.