Interdisciplinary approaches to zoonotic disease

Antimicrobial usage and associated residues and resistance emergence in smallholder beef cattle production systems in Nigeria: A One Health challenge

Livestock intensification has facilitated antimicrobial use (AMU) with consequent antimicrobial resistance (AMR) development. We assessed AMU in beef farms, pathways for residues and resistance dissemination to humans, risk status, residues identification, and drivers for antimicrobial residues and resistance emergence in beef cattle production systems. A cross-sectional survey was conducted in randomly selected beef farms of Northern Nigeria, between 2018 and 2019. Traffic Light model and Disc Diffusion Test were used to assess risk status and determined residues, respectively. Data was analyzed using descriptive statistics and logistic regression models at 95% confidence level. About 92% (n = 608) farmers participated. The majority of farmers managing intensive (78.9%) and semi-intensive (76.6%) farms did not follow antimicrobial dosage instructions. Also, 72.4% and 83.9% of the farmers on intensive and semi-intensive systems, respectively, did not observed withdrawal periods after AMU. Furthermore, 71.5% farmers in intensive and 53.2% in semi-intensive farms used antimicrobials as growth promoters. Antimicrobials frequently used include tetracyclines, sulfonamides and penicillin. Antimicrobial residues and resistance dissemination pathways from beef herds were: consumption of contaminated meat with residues (p = 0.007); contacts with contaminated cattle and fomites (p < 0.001); and contaminated manure and aerosols in farm environment (p = 0.003). Significant drivers of residues and resistance emergence were antimicrobial misuse and overuse (OR = 2.72; 95% CI:1.93-3.83), non-enforcement of laws (OR = 2.98; 95% CI:2.11-4.21), poor education and expertise (OR = 1.52; 95% CI:1.09-2.12), and husbandry management system (OR = 10.24; 95% CI:6.75-15.54). The majority of intensive (63.6%) and semi-intensive (57.63%) farm systems belonged to Class 3 (Red risk) status. Antimicrobial residues were detected in 48.4% intensively and 34.4% semi-intensively managed farms. The study revealed poor practices of AMU in beef cattle production. Many factors were found to influenced antimicrobial residues and resistance occurrence and dissemination. A 'One Health' approach mitigation with adequate sanitation, hygiene, and good biosecurity measures will assure food safety, public and environmental health.

Covid-19 pandemic in the lens of food safety and security

The recently emerged coronavirus disease (COVID-19), which has been characterised as a pandemic by the World Health Organization (WHO), is impacting all parts of human society including agriculture, manufacturing, and tertiary sectors involving all service provision industries. This paper aims to give an overview of potential host reservoirs that could cause pandemic outbreak caused by zoonotic transmission. Amongst all, continues surveillance in slaughterhouse for possible pathogens transmission is needed to prevent next pandemic outbreak. This paper also summarizes the potential threats of pandemic to agriculture and aquaculture sector that control almost the total food supply chain and market. The history lesson from the past, emerging and reemerging infectious disease including the Severe Acute Respiratory Syndrome (SARS) in 2002, Influenza A H1N1 (swine flu) in 2009, Middle East Respiratory Syndrome (MERS) in 2012 and the recent COVID-19 should give us some clue to improve especially the governance to be more ready for next coming pandemic.

Assessing Upstream Determinants of Antibiotic Use in Small-Scale Food Animal Production through a Simulated Client Method

Small-scale food animal production has been celebrated as a means of economic mobility and improved food security but the use of veterinary antibiotics among these producers may be contributing to the spread of antibiotic resistance in animals and humans. In order to improve antibiotic stewardship in this sector, it is critical to identify the drivers of producers’ antibiotic use. This study assessed the determinants of antibiotic use in small-scale food animal production through simulated client visits to veterinary supply stores and surveys with households that owned food animals (n = 117) in Ecuador. Eighty percent of households with food animals owned chickens and 78% of those with chickens owned fewer than 10 birds. Among the households with small-scale food animals, 21% reported giving antibiotics to their food animals within the last six months. Simulated client visits indicated that veterinary sales agents frequently recommended inappropriate antibiotic use, as 66% of sales agents recommended growth promoting antibiotics, and 48% of sales agents recommended an antibiotic that was an inappropriate class for disease treatment. In contrast, few sales agents (3%) were willing to sell colistin, an antibiotic banned for veterinary use in Ecuador as of January 2020, which supports the effectiveness of government regulation in antibiotic stewardship. The cumulative evidence provided by this study indicates that veterinary sales agents play an active role in promoting indiscriminate and inappropriate use of antibiotics in small-scale food animal production.

Mathematically modeling spillovers of an emerging infectious zoonosis with an intermediate host

Modeling the behavior of zoonotic pandemic threats is a key component of their control. Many emerging zoonoses, such as SARS, Nipah, and Hendra, mutated from their wild type while circulating in an intermediate host population, usually a domestic species, to become more transmissible among humans, and this transmission route will only become more likely as agriculture and trade intensifies around the world. Passage through an intermediate host enables many otherwise rare diseases to become better adapted to humans, and so understanding this process with accurate mathematical models is necessary to prevent epidemics of emerging zoonoses, guide policy interventions in public health, and predict the behavior of an epidemic. In this paper, we account for a zoonotic disease mutating in an intermediate host by introducing a new mathematical model for disease transmission among three species. We present a model of these disease dynamics, including the equilibria of the system and the basic reproductive number of the pathogen, finding that in the presence of biologically realistic interspecies transmission parameters, a zoonotic disease with the capacity to mutate in an intermediate host population can establish itself in humans even if its R₀ in humans is less than 1. This result and model can be used to predict the behavior of any zoonosis with an intermediate host and assist efforts to protect public health.

Using local knowledge in emerging infectious disease research

Emerging infectious diseases (EIDs) are a growing global health threat. The Stockholm Paradigm suggests that their toll will grow tragically in the face of climate change, in particular. The best research protocol for predicting and preventing infectious disease emergence states that an urgent search must commence to identify unknown human and animal pathogens. This short communication proposes that the ethnobiological knowledge of indigenous and impoverished communities can be a source of information about some of those unknown pathogens. I present the ecological and anthropological theory behind this proposal, followed by a few case studies that serve as a limited proof of concept. This paper also serves as a call to action for the medical anthropology community. It gives a brief primer on the EID crisis and how anthropology research may be vital to limiting its havoc on global health. Local knowledge is not likely to play a major role in EID research initiatives, but the incorporation of an awareness of EIDs into standard medical anthropological practice would have myriad other benefits.

Determinants of Childhood Zoonotic Enteric Infections in a Semirural Community of Quito, Ecuador

Domestic animals in the household environment have the potential to affect a child's carriage of zoonotic enteric pathogens and risk of diarrhea. This study examines the risk factors associated with pediatric diarrhea and carriage of zoonotic enteric pathogens among children living in communities where smallholder livestock production is prevalent. We conducted an observational study of children younger than 5 years that included the analysis of child (n = 306) and animal (n = 480) fecal samples for Campylobacter spp., atypical enteropathogenic Escherichia coli, Shiga toxin-producing E. coli, Salmonella spp., Yersinia spp., Cryptosporidium parvum, and Giardia lamblia. Among these seven pathogens, Giardia was the most commonly identified pathogen among children and animals in the same household, most of which was found in child-dog pairs. Campylobacter spp. was also relatively common within households, particularly among child-chicken and child-guinea pig pairs. We used multivariable Poisson regression models to assess risk factors associated with a child being positive for at least one zoonotic enteric pathogen or having diarrhea during the last week. Children who interacted with domestic animals-a behavior reported by nearly three-quarters of households owning animals-were at an increased risk of colonization with at least one zoonotic enteric pathogen (prevalence ratio [PR] = 1.56, 95% CI: 1.00-2.42). The risk of diarrhea in the last seven days was elevated but not statistically significant (PR = 2.27, CI: 0.91, 5.67). Interventions that aim to reduce pediatric exposures to enteric pathogens will likely need to be incorporated with approaches that remove animal fecal contamination from the domestic environment and encourage behavior change aimed at reducing children's contact with animal feces through diverse exposure pathways.

Knowledge, attitudes, and practices related to anthrax and animal care: A case-control study in Georgia

Introduction

Anthrax is endemic in Georgia and recent outbreaks prompted a livestock-handler case-control study with a component to evaluate anthrax knowledge, attitudes, and practices (KAP) among livestock handlers or owners.

Methods

Cases were handlers of livestock with confirmed animal anthrax from June 2013-May 2015. Handlers of four matched unaffected animals were selected as controls, two from the same village as the case animal (“village control”) and two from 3–10 km away (“area control”). Descriptive statistics were reported and conditional logistic regression was performed to estimate the magnitude of the association of cases with specific study KAP factors.

Results

Cases were more likely male, had lower level college education, less animal care experience, and provided more animal care to their cattle. Cases had lower odds of burying a suddenly dead animal compared to all controls (Odds Ratio [OR]: 0.32, 95% Confidence interval [CI]:0.12, 0.88) and area controls (OR: 0.32, 95% CI: 0.11, 0.91). On an 8-point knowledge scale, cases having an animal with anthrax had a 1.31 times greater knowledge score compared to all controls (95% CI: 1.03, 1.67). Cases had higher odds of ever having human anthrax or knowing another person who had anthrax compared to all controls (OR: 4.56, 95% CI: 1.45, 14.30) and area controls (OR: 7.16, 95% CI: 1.52, 33.80).

Discussion

Cases were more knowledgeable of anthrax and had better anthrax prevention practices, but these are likely a result of the case investigation and ring vaccination following the death of their animal.

Conclusions

The findings reveal a low level of knowledge and practices related to anthrax control and prevention, and will guide educational material development to fill these gaps.

Frameworks for Preventing, Detecting, and Controlling Zoonotic Diseases

Preventing zoonotic diseases requires coordinated actions by government authorities responsible for human and animal health. Constructing the frameworks needed to foster intersectoral collaboration can be approached in many ways. We highlight 3 examples of approaches to implement zoonotic disease prevention and control programs. The first, rabies control in Ethiopia, was implemented using an umbrella approach: a comprehensive program designed for accelerated impact. The second, a monkeypox program in Democratic Republic of the Congo, was implemented in a stepwise manner, whereby incremental improvements and activities were incorporated into the program. The third approach, a pathogen discovery program, applied in the country of Georgia, was designed to characterize and understand the ecology, epidemiology, and pathogenesis of a new zoonotic pathogen. No one approach is superior, but various factors should be taken into account during design, planning, and implementation.

Animal Husbandry Practices and Perceptions of Zoonotic Infectious Disease Risks Among Livestock Keepers in a Rural Parish of Quito, Ecuador

Small-scale livestock production plays an essential role as a source of income and nutrition for households in low- and middle-income countries, yet these practices can also increase risk of zoonotic infectious diseases, especially among young children. To mitigate this risk, there is a need to better understand how livestock producers perceive and manage risks of disease transmission. Twenty semistructured, in-depth interviews were conducted with small-scale livestock producers in a semirural parish of Quito, Ecuador. Interviews explored livestock-raising practices, including animal health-care practices and use of antimicrobials, family members' interactions with livestock and other animals, and perceptions of health risk associated with these practices and activities. Interviews were analyzed for common themes. Awareness of zoonotic disease transmission was widespread, yet few study participants considered raising livestock a significant health risk for themselves or their families. Several study households reported handling and consuming meat or poultry from sick or dead animals and using animal waste as a fertilizer on their crops. Households typically diagnosed and treated their sick animals, occasionally seeking treatment advice from employees of local animal feed stores where medications, including antimicrobials, are available over the counter. Despite a basic understanding of zoonotic disease risk, this study identified several factors, such as the handling and consumption of sick and dead animals and purchasing medications for sick animals over the counter, that potentially increase the risk of zoonotic disease transmission as well as the development and spread of antimicrobial resistance.

Lessons from the Ebola Outbreak: Action Items for Emerging Infectious Disease Preparedness and Response

As the Ebola outbreak in West Africa wanes, it is time for the international scientific community to reflect on how to improve the detection of and coordinated response to future epidemics. Our interdisciplinary team identified key lessons learned from the Ebola outbreak that can be clustered into three areas: environmental conditions related to early warning systems, host characteristics related to public health, and agent issues that can be addressed through the laboratory sciences. In particular, we need to increase zoonotic surveillance activities, implement more effective ecological health interventions, expand prediction modeling, support medical and public health systems in order to improve local and international responses to epidemics, improve risk communication, better understand the role of social media in outbreak awareness and response, produce better diagnostic tools, create better therapeutic medications, and design better vaccines. This list highlights research priorities and policy actions the global community can take now to be better prepared for future emerging infectious disease outbreaks that threaten global public health and security.