Abstract
Due to the increased demand of animal protein in developing countries, intensive farming is instigated, which results in antibiotic residues in animal-derived products, and eventually, antibiotic resistance. Antibiotic resistance is of great public health concern because the antibiotic-resistant bacteria associated with the animals may be pathogenic to humans, easily transmitted to humans via food chains, and widely disseminated in the environment via animal wastes. These may cause complicated, untreatable, and prolonged infections in humans, leading to higher healthcare cost and sometimes death. In the said countries, antibiotic resistance is so complex and difficult, due to irrational use of antibiotics both in the clinical and agriculture settings, low socioeconomic status, poor sanitation and hygienic status, as well as that zoonotic bacterial pathogens are not regularly cultured, and their resistance to commonly used antibiotics are scarcely investigated (poor surveillance systems). The challenges that follow are of local, national, regional, and international dimensions, as there are no geographic boundaries to impede the spread of antibiotic resistance. In addition, the information assembled in this study through a thorough review of published findings, emphasized the presence of antibiotics in animal-derived products and the phenomenon of multidrug resistance in environmental samples. This therefore calls for strengthening of regulations that direct antibiotic manufacture, distribution, dispensing, and prescription, hence fostering antibiotic stewardship. Joint collaboration across the world with international bodies is needed to assist the developing countries to implement good surveillance of antibiotic use and antibiotic resistance.
Generated Summary
This review article explores the significant issue of antibiotic use in agriculture and its consequences on environmental sources, with a specific emphasis on potential public health implications. The study employs a comprehensive review methodology, drawing upon published findings to synthesize information on the presence of antibiotics in animal-derived products and the phenomenon of multidrug resistance in environmental samples. The research delves into the sources of antibiotic pollution, the mechanisms of antibiotic resistance, and the impact of antibiotic residues on public health. Furthermore, the study considers the challenges faced by developing countries in implementing effective surveillance systems and the need for international collaboration to address antibiotic resistance. The focus includes the impact of antibiotic use in livestock farming, the contamination of the environment, and the associated risks to human health. The study aims to provide insights into the complexities of antibiotic resistance and offers recommendations for mitigating the risks associated with antibiotic use in agriculture.
Key Findings & Statistics
- The average antimicrobial agent consumed per annum of animal produced (per kg) varied across the animal species with values of 45 mg/kg for cattle, 148 mg/kg for chicken, and 172 mg/kg for pigs.
- Van Boeckel et al. projected that antibiotic consumption will approximately double in the BRICS countries.
- Ejo et al. observed an overall prevalence rate of 5.5% of Salmonella isolates identified from raw meat, eggs, milk, and minced meat and burger samples in Ethiopia.
- Rasheed et al. noted an overall incidence of 14.7% of drug-resistant E. coli obtained from vegetable salad, unpasteurized milk, raw chicken, raw meat, and raw egg surface.
- Carballo et al. recovered three tetracycline residues and sixty-three antibiotic-resistant Gram-negative bacteria.
- The study noted the high levels of tetracycline concentration in manure and soil samples procured from three large commercial swine farms, from three different regions in China.
- Lin et al. isolated and characterized one hundred and thirteen enteric bacteria from the Mhlathuze River, KwaZulu-Natal province, South Africa. Of these bacteria, 75.2% were multidrug resistant.
- Wahome noted the microbial contamination of groundwater samples obtained in Ongata Rongai, Kajiado North County, Kenya, with enteric pathogens exhibiting high resistance, between 87.5% and 98.5%, to ampicillin, kanamycin, and sulfamethoxazole.
- In a study in Cameroon, Guetiya Wadoum et al. demonstrated the presence of chloramphenicol and tetracycline residues in concentrations above the maximum residue limit (MRL) recommended by the European Union in 2010, in edible chicken tissues (muscle, gizzards, heart, liver, kidney) and eggs.
- Billah et al. detected ciprofloxacin in higher concentration in egg white, but in lower concentration in egg yolk during treatment of the birds.
- Olufemi and Agboola reported a high oxytetracycline residue in edible beef tissues of cattle slaughtered at Akure, in Nigeria, at violating levels beyond the MRL stipulated by WHO.
- In Vietnam, there has been reported cases of frequent and uncontrolled epidemic diseases.
- Generally, in the developing countries, the level and rate of antibiotic utilization in the farming sector might be influenced by the manner in which the farmers acquire (over the counters) and use these antibiotics.
Other Important Findings
- Antibiotics are used in livestock farming for disease treatment, growth promotion, and improved feed conversion efficiency.
- The choice of antibiotics varies geographically, influenced by animal species, production patterns, farming practices, and regulatory frameworks.
- The persistent use of nonessential antibiotics in livestock farming is linked to expanding farmlands, inadequate policies, and reduced infection control.
- Antibiotic resistance patterns vary between regions and countries, corresponding to the degree of antibiotic consumption, which is guided and regulated by the antibiotic policies of a particular country.
- Antibiotic residues in animal-derived products can negatively impact public health through drug toxicity, immunopathological diseases, carcinogenicity, allergic reactions, and drug sensitization.
- The transmission of antibiotic resistance is a “One Health subject,” encompassing interactions between humans, animals, and the environment.
- Antibiotic resistance in agriculture involves the use of antibiotics for disease treatment, growth promotion, and prevention in livestock.
- The choice of antibiotics and consumption patterns vary based on food animal species, production systems, and regulatory frameworks.
- In developing countries, nonessential antibiotics are used in livestock farming, which can lead to resistance.
- The use of antibiotics in agriculture can lead to antibiotic pollution in the environment.
- Antibiotics used in animals for therapy, prophylaxis, and growth promotion can introduce residues, antibiotic-resistant bacteria, and resistance genes into the environment.
- The misuse of antibiotics, lack of stringent supervision, and inadequate regulations contribute to the spread of resistance.
- Zoonotic pathogens can transfer antibiotic resistance from animals to humans through the food chain, water, and direct contact.
- The World Health Organization (WHO) has developed a Global Action Plan (GAP) to combat antibiotic resistance.
- Surveillance and monitoring of antibiotic use and resistance is crucial for managing the issue.
- Antibiotics may create selective pressure resulting in antibiotic resistance.
- Antibiotics are released from production facilities into the environment in high concentrations.
- The level and rate of antibiotic utilization in farming are influenced by farmers’ practices, existing factors, and the presence of an integrated agricultural system.
- The rise in antibiotic resistance presents a threat to surgical and advanced therapeutic procedures.
- Antimicrobial stewardship is essential to avoid misuse and overuse of antibiotics.
- Surveillance systems for antibiotic use and resistance differ across countries.
- The study identifies a need for international cooperation to address antibiotic resistance.
Limitations Noted in the Document
- The study highlights the challenges faced by developing countries in developing and maintaining surveillance systems, including a lack of funding, resources, and skilled personnel.
- The diversity in antibiotic consumption patterns across different countries, due to varying agricultural practices and regulatory frameworks, presents challenges in developing generalized strategies.
- The limitations are caused by the incomplete data on antimicrobial consumption and sales.
- The study acknowledges the potential for variation in resistance patterns due to regional differences.
- Inadequate and insufficient policies contribute to the spread of antibiotic resistance.
Conclusion
The relentless employment of antibiotics in both clinical and agricultural sectors has fueled the rapid emergence and spread of antibiotic resistance, posing a critical threat to public health and environmental integrity. The study shows the intricate ways in which antibiotic use in livestock farming can lead to the presence of antibiotic residues in animal-derived products, with potential adverse effects on human health through drug toxicity, immunopathological diseases, and other health concerns. The study also emphasizes the importance of understanding the mechanisms of resistance, the role of the environment as a reservoir, and the critical need for continuous surveillance. A critical takeaway is the importance of multi-faceted interventions that span the agricultural, environmental, and healthcare domains. Key strategies include enforcing judicious use of antibiotics, implementing improved hygiene practices, promoting responsible agricultural practices, and fostering international cooperation. The lack of knowledge regarding prudent antibiotic use, compounded by poor sanitation and inadequate infrastructure, exacerbates the situation, particularly in developing nations. The study advocates for an integrated “One Health Approach” to combat antibiotic resistance, emphasizing the interconnectedness of human, animal, and environmental health. The implementation of strict control and/or regulations, continuous surveillance, and enforcement of legitimate purchase and employment of antibiotics is essential in animal farming. Moreover, the establishment of a network of actions from veterinarians, livestock producers, pharmacists, and regulatory authorities is essential to enforce prudent antibiotic use. In addition to these efforts, the sensitization of farmers and the general population to the dangers of improper antibiotic use is inevitable to prevent the rising of antibiotic resistance. Thus, the need to focus on the responsible use of antibiotics and the need for collaborative action among various entities is of utmost importance.