Contribution of wastewater irrigated vegetables to the prevalence of soil-transmitted helminth infection among female farmers in Addis Ababa, Ethiopia.

BACKGROUND: Untreated or inadequately treated wastewater carrying human feces can host helminth eggs and larvae, contaminating the soil and plants that are irrigated with it. In Addis Ababa, farmers use untreated wastewater to grow vegetables; however, there are little data currently available published on vegetables' contribution to the prevalence of helminth among female farmers along the Akaki River, in Addis Ababa, Ethiopia. METHODS: A cross-sectional study was conducted in Addis Ababa City in February 2022. A stratified random sampling method was used to sample farming households. The sample size for each district was determined by a proportional allocation to the total number of households in the area. Two hundred and fifty-two composite vegetable samples and 101 farmers' stool samples were collected and analyzed for helminth prevalence. Data on socio-demographics were collected by trained data collators using a structured questionnaire. Kato-Katz concentration was used to detect STH from a stool sample. Stata version 14.0 was used to process the data. Poisson regression was used to identify the association between STH prevalence in the vegetable and the farm's stool. RESULTS: Helminths were found in 67.5% of vegetables sampled and 20.8% of female farmers' stools. Ascaris lumbricoides eggs (vegetable 48.4% and stool 9.9%) were identified in all analyzed samples. Hookworm eggs (vegetable 13.1% and stool 8.9%) and Trichuris trichiura eggs (vegetable 5.9% and stool 2%) were also isolated. The total number of helminth eggs present in wastewater-irrigated vegetables and female farmers' stool had a positive association (p < 0.05) with a regression coefficient of 1.92 (95% CI = 1.56-2.28). CONCLUSIONS: The study found a significant prevalence of helminth infections, particularly Ascaris lumbricoides, in stool and vegetable samples irrigated with wastewater. A clear association was found between vegetable production and a higher prevalence of helminth infections among female farmers. Therefore, it is important to ensure that farmers are educated in the importance of food washing and sanitation/hygiene practices when using wastewater irrigation for vegetable crops.

Prevalence and risk factors of childhood diarrhea among wastewater irrigating urban farming households in Addis Ababa.

INTRODUCTION: Childhood diarrhea is one of the major contributors to the morbidity of under-five children in Ethiopia. Although researchers determine the risk factors varyingly, the exposure route to the pathogens is usually complicated. This study aims to investigate the prevalence and risk factors of diarrhea among children under the age of five among wastewater irrigation farming households in Addis Ababa, Ethiopia. METHODS: Cross-sectional study was conducted among 402 farming households from November 2021 to February 2022. Data was collected using a face-to-face interviewer-administered questionnaire. Stata version 14 software was used to analyze data. Factors associated with the prevalence of diarrhea was identified using binary logistic regression. Multivariable analysis was carried out to determine an adjusted odds ratio at a confidence level of 95% and level of significance at 0.05. RESULTS: The overall prevalence of under-five children diarrheal cases was 22.3%. The odds of diarrhea are associated with a multitude of variables. Major wastewater-related determinants associated with diarrhea are body washing with irrigation water [AOR: 37.7, 95%CI (3.1, 358)], contaminated cloth with irrigation water [AOR:10.8,95%CI(0.6, 205)], use of protective clothing during farm work [28.9,95%CI (3.9, 215)], use of farm work cloths at home [AOR: 31.7, 95%CI (4.4, 226)], and bringing unwashed farm tools to home [94 (5.7, 1575)]. CONCLUSION: The high prevalence of under-five children diarrheal disease among wastewater irrigation households was strongly associated with factors related to occupational exposure. Thus, to decrease childhood diarrheal among urban agriculture farmers, appropriate precautions need to be taken.

Distribution of helminth eggs in environmental and stool samples of farming households along Akaki River in Addis Ababa, Ethiopia.

BACKGROUND: Helminth infections are a public health issue in countries with poor sanitation facilities. However, there little information on the epidemiological association between helminths in wastewater and soil samples and rates of helminth infection among farming households along the Akaki River in Addis Ababa, Ethiopia. METHODS: A cross-sectional study was conducted between November 2021 and February 2022. A stratified random sampling technique was used to select farming households. The sample size for each district was determined by a proportionate allocation to the number of households. From wastewater-irrigated farms, 70 wastewater samples, 28 soil samples, and 86 farmers' stool samples were collected and analyzed for helminths. A questionnaire was used to gather ethnographic data, about farming households, whereas wastewater and soil sample analysis was used to generate quantitative data on helminth loads. The data were systematically analysed by developing themes, and bias evaluated using triangulation validation methodologies. Potential pathways to helminth infection were evaluated by measuring. Total number of helminth eggs in wastewater, soil samples and farmer's stools was investigated using Poisson regression. RESULTS: In this study, 82.9% of wastewater samples, 57.1% of soil samples, and 18.6% of farmers' stool samples contained helminth eggs. The most prevalent helminth was Ascaris lumbricoides in all samples (wastewater 67%, soil 25%, and stool 10.5%), followed by hookworm (wastewater 10%, soil 21.4%, and stool 6.9%) and Trichuris trichiura eggs (wastewater 5.7%, soil 10.7%, and stool 1.2%). There was a positive association between the total number of helminth eggs in wastewater and soil samples with counts in farmers' stool. The Poisson regression coefficients for wastewater and soil were, 1.63 (95% CI = 1.34-1.92) and 1.70 (95% CI = 1.39-2.01), (p < 0.05). CONCLUSIONS: This research has shown a clear association between the total helminth eggs in wastewater and soil samples and farmer stools along the Akaki River. Therefore, an integrated approach is essential to address the issue in this area and prevent the spread of further helminth infections.

Fecal Contamination in the Wastewater Irrigation System and its Health Threat to Wastewater-Based Farming Households in Addis Ababa, Ethiopia.

Due to rapidly growing demand, the production of vegetables is increasing along the Akaki Rivers. The objective of this study was to examine the degree of fecal contamination and levels of fecal contamination and dissemination throughout the wastewater irrigation system. Irrigation water, irrigated soil, and leafy vegetables were collected twice during 2 vegetable growing seasons, at the maturity period of the growing season, from 19 sampling points along the 2 Akaki Rivers. Composite samples were taken from all sampling points and E.coli was enumerated. The mean E.coli load in wastewater and non-wastewater sources were 1.16±5.53 CFU/100 ml and 2.232±1.292 CFU/100 ml respectively. All counts of E. coli in the wastewater exceeded the WHO's standards indicating that the irrigation water quality was unacceptable. In the wastewater-irrigated and non-wastewater-irrigated soil, the mean E.coli were 3.62 ±1.582 CFU/g and 1.322±87.1 CFU/g respectively. Meanwhile, the mean E.coli counts on the lettuce and Swiss chard were 78 ± 2 CFU/g and 44 ±3CFU/g respectively. The E.coli count on the leafy vegetables was found to be associated with the E.coli in the wastewater and soil. The production of leafy vegetables using wastewater with unacceptably high levels of E.coli and high occupational exposure introduces high levels of risk to the farming communities and to the consumers. Leafy, low-growing raw edible vegetables need careful treatment during food production and harvesting procedures or activities.

Urinary 8-OHdG level is not affected by geography and trace elements in nail of residents of Addis Ababa: It is shaped by interactions between different social factors.

The objective of this study was to evaluate the association between exposure to heavy metals and oxidative DNA damage among residents living in the potentially more polluted downstream (Akaki-Kality) area of Addis Ababa, in comparison to the upstream area (Gullele). For this, 8-hydroxy-2'-deoxyguanosine (8-OHdG) was used as a biomarker for oxidative DNA damage and heavy metals (Fe, Zn, Mn, Cu, Ni, Cr, Pb, As) as indicators of exposure. The concentrations of heavy metals in nails were determined using inductively coupled plasma optical emission spectroscopy (ICP-OES), and 8-OHdG in urine using Enzyme-Linked with Immunosorbent Assay (ELISA), from 95 residents of the two areas, upstream and downstream. The urinary 8-OHdG concentration was not significantly different (p = 0.05) between the two Sub-Cities, with mean of 18.50 ± 4.37 ng/mg Creatinine in Akaki-Kality and 17.30 ± 5.83 ng/mg Creatinine in Gullele. Also, there were no statistically significant (p = 0.05) difference among the different demographic groups according to gender, age, educational status, body mass index or habit of alcohol consumption. However, the interactions of sex with age, sex with alcohol consumption and alcohol consumption with education were found to affect the urinary 8-OHdG levels of residents of the two Sub-Cities. The mean concentrations (µg/g) of the elements were 488 and 1035 for Fe, 106 and 251 for Zn, 13.0 and 31.2 for Mn, 5.23 and 6.63 for Cu, 11.2 and 7.39 for Ni, 2.23 and 2.02 for Cr, 0.09 and 0.63 for Pb; and 0.16 and 0.25 for As, in nail samples from Akaki-Kality and Gullele, respectively. The determined concentrations of the heavy metals in nails were not significantly associated (p = 0.05) with the corresponding urinary levels of 8-OHdG. Hence, the observed 8-OHdG might have been caused by environmental exposure to toxic substances other than the analyzed heavy metals.

Absence of significant association of trace elements in nails with urinary KIM-1 biomarker among residents of Addis Ababa in Upper Awash Basin, Ethiopia: a cross-sectional study.

The Akaki River in the Upper Awash Basin, which flows through Addis Ababa, the capital city of Ethiopia, has been highly polluted by sewage from factories and residential areas. A population-based cross-sectional study was used to assess the association between trace elements and kidney injury from residents living in polluted areas downstream (Akaki-Kality) versus upstream (Gullele) in Sub-Cities of Addis Ababa. A total of 95 individuals (53 from Akaki-Kality and 42 from Gullele) were included in the study. Kidney injury molecule 1 (KIM-1), lead, arsenic, cadmium, cobalt, lead, manganese, zinc, iron, copper, chromium and nickel were evaluated in residents' urine and nail samples. A large proportion (74%) of the sample population contained KIM-1, including 81% residents in Akaki-Kality and 64% residents in Gullele. KIM-1 was, however, not significantly different (p = 0.05) between the two Sub-Cities, with median of 0.224 ng/mL in Akaki-Kality and 0.152 ng/mL in Gullele. Most of the analyzed elements, except Pb, As, Cd and Co, were found in all of the nail samples, with median (µg/g) in the range of 442‒714 Fe, 97.0‒246 Zn, 11.6‒24.1 Mn, 4.49‒5.85 Cu, 1.46‒1.66 Cr and 1.22‒1.41 Ni. The high incidence of KIM-1 indicates a potential for long term renal tubular damage among residents of the Sub-Cities. The concentrations of the elements in nails were, however, not significantly associated (p = 0.05) with the corresponding levels of KIM-1 in urine. Hence, the observed KIM-1 might be related to exposure to toxic substances or factors other than those included in this study.

Developing Surrogate Markers for Predicting Antibiotic Resistance "Hot Spots" in Rivers Where Limited Data Are Available.

Pinpointing environmental antibiotic resistance (AR) hot spots in low-and middle-income countries (LMICs) is hindered by a lack of available and comparable AR monitoring data relevant to such settings. Addressing this problem, we performed a comprehensive spatial and seasonal assessment of water quality and AR conditions in a Malaysian river catchment to identify potential "simple" surrogates that mirror elevated AR. We screened for resistant coliforms, 22 antibiotics, 287 AR genes and integrons, and routine water quality parameters, covering absolute concentrations and mass loadings. To understand relationships, we introduced standardized "effect sizes" (Cohen's D) for AR monitoring to improve comparability of field studies. Overall, water quality generally declined and environmental AR levels increased as one moved down the catchment without major seasonal variations, except total antibiotic concentrations that were higher in the dry season (Cohen's D > 0.8, P < 0.05). Among simple surrogates, dissolved oxygen (DO) most strongly correlated (inversely) with total AR gene concentrations (Spearman's ρ 0.81, P < 0.05). We suspect this results from minimally treated sewage inputs, which also contain AR bacteria and genes, depleting DO in the most impacted reaches. Thus, although DO is not a measure of AR, lower DO levels reflect wastewater inputs, flagging possible AR hot spots. DO measurement is inexpensive, already monitored in many catchments, and exists in many numerical water quality models (e.g., oxygen sag curves). Therefore, we propose combining DO data and prospective modeling to guide local interventions, especially in LMIC rivers with limited data.

Multidrug-resistant bacteria and microbial communities in a river estuary with fragmented suburban waste management.

River systems in developing and emerging countries are often fragmented relative to land and waste management in their catchment. The impact of inconsistent waste management and releases is a major challenge in water quality management. To examine how anthropogenic activities and estuarine effects impact water quality, we characterised water conditions, in-situ microbiomes, profiles of faecal pollution indicator, pathogenic and antibiotic resistant bacteria in the River Melayu, Southern Malaysia. Overall, upstream sampling locations were distinguished from those closer to the coastline by physicochemical parameters and bacterial communities. The abundances of bacterial DNA, total E. coli marker genes, culturable bacteria as well as antibiotic resistance ESBL-producing bacteria were elevated at upstream sampling locations especially near discharge of a wastewater oxidation pond. Furthermore, 85.7% of E. faecalis was multidrug-resistant (MDR), whereas 100% of E. cloacae, E. coli, K. pneumoniae were MDR. Overall, this work demonstrates how pollution in river estuaries does not monotonically change from inland towards the coast but varies according to local waste releases and tidal mixing. We also show that surrogate markers, such dissolved oxygen, Bacteroides and Prevotella abundances, and the rodA qPCR assay for total E. coli, can identify locations on a river that deserve immediate attention to mitigate AMR spread through improved waste management.

The"Newcastle Nomogram"-Statistical modelling predicts malignant transformation in potentially malignant disorders.

BACKGROUND: Nomograms are graphical calculating devices used to predict risk of malignant transformation (MT) or response to treatment during cancer management. To date, a nomogram has not been used to predict clinical outcome during oral potentially malignant disorder (PMD) treatment. The aim of this study was to create a nomogram for use by clinicians to predict the probability of MT, thereby facilitating accurate assessment of risk and objective decision-making during individual patient management. METHODS: Clinico-pathological data from a previously treated cohort of 590 newly presenting PMD patients were reviewed and clinical outcomes categorized as disease free, persistent PMD or MT. Multiple logistic regression was used to predict the probability of MT in the cohort using age, gender, lesion type, site and incision biopsy histopathological diagnoses. Internal validation and calibration of the model was performed using the bootstrap method (n = 1000), and bias-corrected indices of model performance were computed. RESULTS: Potentially malignant disorders were predominantly leukoplakias (79%), presenting most frequently at floor of mouth and lateral tongue sites (51%); 99 patients (17%) developed oral squamous cell carcinoma during the study period. The nomogram performed well when MT predictions were compared with patient outcome data, demonstrating good bias-corrected discrimination and calibration (Dxy  = 0.58; C = 0.790), with a sensitivity of 87% and specificity 63%, and a positive predictive value of 32% and negative predictive value 96%. CONCLUSION: The "Newcastle Nomogram" has been developed to predict the probability of MT in PMD, based on an internally validated statistical model. Based upon readily available and patient-specific clinico-pathological data, it provides clinicians with a pragmatic diagrammatic aid for clinical decision-making during diagnosis and management of PMD.

A cross-sectional examination of the relationship between approaches to learning and perceived stress among medical students in Malaysia.

Background: Learning approaches have been proposed to affect the experience of psychological stress among tertiary students in recent years. This relationship becomes important in stressful environments such as medical schools. However, the relationship between stress and learning approaches is not well understood, and often studies done cannot be generalized due to different sociocultural differences. In particular, no study in Malaysia has looked at learning approaches among medical students. Aims: To address this gap, we examined the relationship between perceived stress and learning approaches by considering sources of stress. Methodology: The Perceived Stress Scale (PSS-10), Medical Student Stressor Questionnaire, and the Revised Two-Factor Study Process Questionnaire were answered by the preclinical and final-year students studying MBBS in a Malaysian campus of British University. Results: Deep learning was positively and surface learning negatively associated with perception of coping with stress. In this study, neither approaches were associated with psychological stress as opposed to previous reports. We found surface learners to report higher level of stress associated with social stressors. We found students' self-perception of feeling incompetent and feeling they need to do well to be significant sources of stress. Discussion: Deep learning promotes psychological resilience. This is of paramount importance in learning environments where stress is highly prevalent such as medical school. Promotion of deep learning among medical students is required at earlier stages as they tend to solidify their approach through their university years and carry that approach beyond school into their workplace.

Potentially malignant disorders revisited-The lichenoid lesion/proliferative verrucous leukoplakia conundrum.

BACKGROUND: Clinically identifiable potentially malignant disorders (PMD) precede oral squamous cell carcinoma development. Oral lichenoid lesions (OLL) and proliferative verrucous leukoplakia (PVL) are specific precursor lesions believed to exhibit both treatment resistance and a high risk of malignant transformation (MT). METHODS: A retrospective review of 590 PMD patients treated in Northern England by CO2 laser surgery between 1996 and 2014 was carried out. Lesions exhibiting lichenoid or proliferative verrucous features were identified from the patient database and their clinicopathological features and outcome post-treatment determined at the study census date of 31 December 2014. RESULTS: One hundred and 98 patients were identified as follows: 118 OLL and 80 PVL, most frequently leukoplakia at ventrolateral tongue and floor of mouth sites, equally distributed between males and females. Most exhibited dysplasia on incision biopsy (72% OLL; 85% PVL) and were treated by laser excision rather than ablation (88.1% OLL; 86.25% PVL). OLL were more common in younger patients (OLL 57.1 year; PVL 62.25 years; P = .008) and more likely than PVL to present as erythroleukoplakia (OLL 15.3%; PVL 2.5%; P = .003). Whilst no significant difference was seen between OLL and PVL achieving disease-free status (69.5% and 65%, respectively; P = .55), this was less than the overall PMD cohort (74.2%). MT was identified in 2 OLL (1.7%) and 2 PVL (2.5%) during follow-up. CONCLUSION: One-third of PMD cases showed features of OLL or PVL, probably representing a disease presentation continuum. Post-treatment disease-free status was less common in OLL and PVL, although MT was infrequent.

Pneumothorax after orthognathic surgery.

We report the case of an 18-year-old girl who had pneumothorax two days after bimaxillary osteotomy to correct a severe Class II malocclusion. Chest radiograph showed left-sided pneumothorax with complete collapse of the underlying lung and mediastinal shift to the left. A chest drain was inserted and she made an uneventful recovery. The aetiology may be iatrogenic or spontaneous, but we have found no previous reports of pneumothorax after orthognathic surgery.