Spatial Exposure of Agricultural Antimicrobial Resistance in Relation to Free-Ranging Domestic Chicken Movement Patterns among Agricultural Communities in Ecuador

Effect of a Homestead Food Production and Food Hygiene Intervention on Biomarkers of Environmental Enteric Dysfunction in Children Younger Than 24 Months in Rural Bangladesh: A Cluster-Randomized Controlled Trial

Poor sanitation and hygiene practices and inadequate diets can contribute to environmental enteric dysfunction (EED). We evaluated the impact of a combined homestead food production and food hygiene intervention on EED biomarkers in young children in rural Bangladesh. The analysis was conducted within the Food and Agricultural Approaches to Reducing Malnutrition (FAARM) cluster-randomized trial in Sylhet, Bangladesh. The FAARM trial enrolled 2,705 married women and their children younger than 3 years of age in 96 settlements (geographic clusters): 48 intervention and 48 control. The 3-year intervention (2015-2018) included training on gardening, poultry rearing, and improved nutrition practices and was supplemented by an 8-month food hygiene behavior change component, implemented from mid-2017. We analyzed data on 574 children age 0 to 24 months with multilevel linear regression. We assessed fecal myeloperoxidase (MPO), neopterin (NEO), and alpha-1-antitrypsin (AAT) as biomarkers of EED, and serum C-reactive protein (CRP) and alpha-1-acid glycoprotein (AGP) as biomarkers of systemic inflammation, using ELISA. There was no intervention effect on NEO, AAT, CRP, and AGP concentrations, but, surprisingly, MPO levels were increased in children of the intervention group (0.11 log ng/mL; 95% CI, 0.001-0.22). This increase was greater with increasing child age and among intervention households with poultry that were not kept in a shed. A combined homestead food production and food hygiene intervention did not decrease EED in children in our study setting. Small-scale poultry rearing promoted by the intervention might be a risk factor for EED.

Risk factors for extended-spectrum beta-lactamase (ESBL)-producing E. coli carriage among children in a food animal-producing region of Ecuador: A repeated measures observational study

BACKGROUND

The spread of antibiotic-resistant bacteria may be driven by human-animal-environment interactions, especially in regions with limited restrictions on antibiotic use, widespread food animal production, and free-roaming domestic animals. In this study, we aimed to identify risk factors related to commercial food animal production, small-scale or "backyard" food animal production, domestic animal ownership, and practices related to animal handling, waste disposal, and antibiotic use in Ecuadorian communities.

METHODS AND FINDINGS

We conducted a repeated measures study from 2018 to 2021 in 7 semirural parishes of Quito, Ecuador to identify determinants of third-generation cephalosporin-resistant E. coli (3GCR-EC) and extended-spectrum beta-lactamase E. coli (ESBL-EC) in children. We collected 1,699 fecal samples from 600 children and 1,871 domestic animal fecal samples from 376 of the same households at up to 5 time points per household over the 3-year study period. We used multivariable log-binomial regression models to estimate relative risks (RR) of 3GCR-EC and ESBL-EC carriage, adjusting for child sex and age, caregiver education, household wealth, and recent child antibiotic use. Risk factors for 3GCR-EC included living within 5 km of more than 5 commercial food animal operations (RR: 1.26; 95% confidence interval (CI): 1.10, 1.45; p-value: 0.001), household pig ownership (RR: 1.23; 95% CI: 1.02, 1.48; p-value: 0.030) and child pet contact (RR: 1.23; 95% CI: 1.09, 1.39; p-value: 0.001). Risk factors for ESBL-EC were dog ownership (RR: 1.35; 95% CI: 1.00, 1.83; p-value: 0.053), child pet contact (RR: 1.54; 95% CI: 1.10, 2.16; p-value: 0.012), and placing animal feces on household land/crops (RR: 1.63; 95% CI: 1.09, 2.46; p-value: 0.019). The primary limitations of this study are the use of proxy and self-reported exposure measures and the use of a single beta-lactamase drug (ceftazidime with clavulanic acid) in combination disk diffusion tests for ESBL confirmation, potentially underestimating phenotypic ESBL production among cephalosporin-resistant E. coli isolates. To improve ESBL determination, it is recommended to use 2 combination disk diffusion tests (ceftazidime with clavulanic acid and cefotaxime with clavulanic acid) for ESBL confirmatory testing. Future studies should also characterize transmission pathways by assessing antibiotic resistance in commercial food animals and environmental reservoirs.

CONCLUSIONS

In this study, we observed an increase in enteric colonization of antibiotic-resistant bacteria among children with exposures to domestic animals and their waste in the household environment and children living in areas with a higher density of commercial food animal production operations.

Human Colonization with Antibiotic-Resistant Bacteria from Nonoccupational Exposure to Domesticated Animals in Low- and Middle-Income Countries: A Critical Review

Data on community-acquired antibiotic-resistant bacterial infections are particularly sparse in low- and middle-income countries (LMICs). Limited surveillance and oversight of antibiotic use in food-producing animals, inadequate access to safe drinking water, and insufficient sanitation and hygiene infrastructure in LMICs could exacerbate the risk of zoonotic antibiotic resistance transmission. This critical review compiles evidence of zoonotic exchange of antibiotic-resistant bacteria (ARB) or antibiotic resistance genes (ARGs) within households and backyard farms in LMICs, as well as assesses transmission mechanisms, risk factors, and environmental transmission pathways. Overall, substantial evidence exists for exchange of antibiotic resistance between domesticated animals and in-contact humans. Whole bacteria transmission and horizontal gene transfer between humans and animals were demonstrated within and between households and backyard farms. Further, we identified water, soil, and animal food products as environmental transmission pathways for exchange of ARB and ARGs between animals and humans, although directionality of transmission is poorly understood. Herein we propose study designs, methods, and topical considerations for priority incorporation into future One Health research to inform effective interventions and policies to disrupt zoonotic antibiotic resistance exchange in low-income communities.

Risk factors for third-generation cephalosporin-resistant and extended-spectrum β-lactamase-producing Escherichia coli carriage in domestic animals of semirural parishes east of Quito, Ecuador

Extended-spectrum β-lactamase (ESBL)-producing and other antimicrobial resistant (AR) Escherichia coli threaten human and animal health worldwide. This study examined risk factors for domestic animal colonization with ceftriaxone-resistant (CR) and ESBL-producing E. coli in semirural parishes east of Quito, Ecuador, where small-scale food animal production is common. Survey data regarding household characteristics, animal care, and antimicrobial use were collected from 304 households over three sampling cycles, and 1195 environmental animal fecal samples were assessed for E. coli presence and antimicrobial susceptibility. Multivariable regression analyses were used to assess potential risk factors for CR and ESBL-producing E. coli carriage. Overall, CR and ESBL-producing E. coli were detected in 56% and 10% of all fecal samples, respectively. The odds of CR E. coli carriage were greater among dogs at households that lived within a 5 km radius of more than 5 commercial food animal facilities (OR 1.72, 95% CI 1.15-2.58) and lower among dogs living at households that used antimicrobials for their animal(s) based on veterinary/pharmacy recommendation (OR 0.18, 95% CI 0.04-0.96). Increased odds of canine ESBL-producing E. coli carriage were associated with recent antimicrobial use in any household animal (OR 2.69, 95% CI 1.02-7.10) and purchase of antimicrobials from pet food stores (OR 6.83, 95% CI 1.32-35.35). Food animals at households that owned more than 3 species (OR 0.64, 95% CI 0.42-0.97), that used antimicrobials for growth promotion (OR 0.41, 95% CI 0.19-0.89), and that obtained antimicrobials from pet food stores (OR 0.47, 95% CI 0.25-0.89) had decreased odds of CR E. coli carriage, while food animals at households with more than 5 people (OR 2.22, 95% CI 1.23-3.99) and located within 1 km of a commercial food animal facility (OR 2.57, 95% CI 1.08-6.12) had increased odds of ESBL-producing E. coli carriage. Together, these results highlight the complexity of antimicrobial resistance among domestic animals in this setting.

"Chicken dumping": Motivations and perceptions in shifting poultry production practices

Non-governmental organizations (NGOs) often implement overseas development aid through intensive small-scale animal agriculture to alleviate food insecurity in low- and middle-income countries. Intensive animal farming can pose unclear outcomes to households engaged in the practice because of the reliance on industrial animal breeds that are reared with antibiotics and raised in higher densities compared to traditional scavenging husbandry systems. As a result, intensive small-scale farming operations that lack proper infrastructure, training, and financial resources could facilitate the spread of antimicrobial resistance and infectious diseases. We applied a mixed-methods framework towards analyzing the effectiveness of small-scale broiler chicken farming in northern Ecuador. First, from May 2016 – May 2017, our observational surveys indicated that intensive small-scale poultry farming follows a boom-and-bust cycle that is extremely vulnerable to environmental stressors. Second, in May 2016, we followed a cohort of households enrolled in a poultry development project led by an NGO. We observed a substantial decline in chicken survivorship from Survey period 1 to 2 (mean chicken count decrease from 50 to 35 corresponding to a 70% survivorship) and from Survey period 2 to 3 (mean chicken count decrease from 35 to 20.3 corresponding to a 58% survivorship). Heads of households were self-reporting broiler chicken survivorship substantially higher than our recorded observations during survey period two (46 compared to 35 respectively) and three (44.3 compared to 20.3 respectively). We speculate that if households continue to inaccurately report poultry demographics, then it could perpetuate a negative feedback loop where NGOs continue to conduct the same intervention practices without receiving accurate outcome metrics. Third, we used semi-structured questionnaires to determine that access to financial resources was the major motivation for determining when to farm broiler chickens. Intensive small-scale poultry farming can be unreliable and disease-enhancing, yet also associated with dubious self-reports of success.

Food Safety Considerations Related to the Consumption and Handling of Game Meat in North America

Emerging foodborne pathogens present a threat to public health. It is now recognized that several foodborne pathogens originate from wildlife as demonstrated by recent global disease outbreaks. Zoonotic spillover events are closely related to the ubiquity of parasitic, bacterial, and viral pathogens present within human and animal populations and their surrounding environment. Foodborne diseases have economic and international trade impacts, incentivizing effective wildlife disease management. In North America, there are no food safety standards for handling and consumption of free-ranging game meat. Game meat consumption continues to rise in North America; however, this growing practice could place recreational hunters and game meat consumers at increased risk of foodborne diseases. Recreational hunters should follow effective game meat food hygiene practices from harvest to storage and consumption. Here, we provide a synthesis review that evaluates the ecological and epidemiological drivers of foodborne disease risk in North American hunter populations that are associated with the harvest and consumption of terrestrial mammal game meat. We anticipate this work could serve as a foundation of preventive measures that mitigate foodborne disease transmission between free-ranging mammalian and human populations.