The poultry waste dumpsites of Idi Ayunre and environs: Reservoirs and distributors of disease-causing antibiotic resistant pathogens
Sunday Omeike, PhD
Poultry business is a major contributor to Nigeria’s economy and source of meats and eggs for domestic and commercial purposes. A 2018 FAO report estimated over 180 million birds mostly in semi-intensive and intensive farms, and Netherlands Enterprise Agency’s recent report says they contribute approximately 25% to Nigeria’s agricultural GDP.
This increasing economic importance of poultry farms, which could be said to be partially fuelled by antibiotic usage for health and weight gain, also leads to concomitant increase in poultry waste (litter) generated and disposed of into the environment. While antibiotic usage cannot be quantified without hard evidence, its effect can be tracked in poultry litter, as evident in Idi Ayunre town and its several adjoining communities.
Located in Oluyole Local Government Area, Ibadan, Oyo State, these communities host over sixty small, middle and large scale poultry farms, and their associated foul-smelling dump sites. While travelers can spot the Akilapa dumpsite sitting on a large expanse of land a few kilometers after the now-abandoned exit toll gates of Lagos-Ibadan expressway, there are several others hidden in these communities and their persistence could be a ticking disease time-bomb.
To understand how these dumpsites harbour disease-causing bacterial pathogens, a microbiological analysis carried out at McPherson University’s microbiology laboratory paints a worrying picture. The bacteria population runs into millions in just one gram of litter, while species of Shigella, Escherichia coli and pathogens of the enterobacteriaceae group known for their food-poisoning ability were also observed. This, Dr. Olaitan Olajuyigbe, a chief research officer at Nigerian Institute for Oceanography and Marine Research (NIOMR), Lagos, says could have wide-ranging effects on the entire population.
“The occurrence of pathogens such as Shigella and Escherichia coli is of a great public health importance. In most towns in Southwest Nigeria, livestock and chicken are allowed to roam about freely in search of food, and in cases where the livestock feed on this dump site, there is a high risk of transmission of these pathogens onto the livestock and other animals. This can possibly be transmitted to others sources such as food and water as well, and where adequate hygiene is not maintained and adequate processing of the animals for food is not done, it can lead to food infection or poisoning,” she stated.
Further checks on what organisms antibiotics would eliminate in the event of an infection showed that six of eight commonly used antibiotics would not kill any of them. This is even of greater concern to the public as global antibiotic resistance is predicted to increase, a situation Dr. Ayansina Ayangbenro finds worrying.
“It is getting scary by the day to think that the world is moving closer to an era where no antimicrobial works again, the use of different antibiotics in large scale by this industry across the world for prophylactic, therapeutic and growth promotion is a major source of environmental and public health concern.” the environmental microbiologist said.
That the farms dump this waste unabashed despite its potential ripple effect on the community- both human and environment- is a cause for concern due to their potential to create several hotspots for antibiotic resistance (AMR) transfer and its attendant effects, says Dr. Yinka Somorin, a food microbiologist and Research Fellow at the School of Pharmacy, Queen's University Belfast.
“These practices are risky and could represent a transmission route for antimicrobial resistance across the food chain,” he started. “Firstly, multidrug-resistant (MDR) pathogens could be transmitted directly to poultry workers and farmers handling the wastes and cause infections which will be difficult to treat. Also, MDR pathogens could leach into drinking and recreational water systems in the community thus becoming a source of contamination to the wider population in the community.”
Plate showing microbial populations on growth medium (left), and susceptibility of bacterial isolates to antibiotics (right) with two clear zones showing effectiveness of only two antibiotics and resistance to six others.
A community that ‘benefits’ but silently complains
Idi Ayunre locals glow when discussing the poultry revolution in their community: the jobs, vibrant transportation, and several other avenues stemming from poultry and its wastes to make ends meet. One of such is the packaging and transportation of the waste to other areas of the State and indeed, other States, for use in cropping and fish supplement. Both practices were confirmed by locals, while a worker who earns additional income by bagging and loading the waste onto vehicles for transport detailed his role.
“When the trailers come, we help them package the waste into sacks and they transport some to Akinyele and other areas where they are used on maize and pepper farms. They also take it to other places where they use the waste for other purposes that I do not know,” he explained.
Another source of local Internally Generated Revenue is the collection and re-use of poultry waste sacks used in dumping the wastes and according to a local guide, there is commotion whenever a poultry farm’s truck pulls up to dump its waste.
“There is serious commotion whenever they come. The children and women will run after the truck into the dump sites to get the large and better sacks. They re-wash the sacks and use to package crop produce they intend to sell on market days,” the local guide explained.
This practice, Dr. Somorin said should be discontinued and in a situation where that is not possible, education on proper disinfection and re-use should be pursued.
“Using such sacks to bag food items for sale could contaminate the foods with multi-drug resistant bacteria. Re-use of sacks used to transport poultry waste should be discouraged or when that is impossible, decontamination or disinfection of sacks must be done to remove any possible pathogen present.”
While no local government official or poultry farm was keen to broach, discussion with some locals about some of the findings resulted in mood changes as the hard truths set in after a few minutes. According to a youth leader of one of such communities that has five dumpsites, there has previously been some tension between the community and poultries regarding location of their dump sites close to villages and its attendant air pollution.
“There was a time we complained about the smell and increasing presence at close proximity to the people and it was agreed that they [the farms] would burn the dump sites regularly, while also relocating most of their dumping activities deeper into the hinterlands of the community,” he said while giving location of some other dumpsites.
To combat this silent but widespread distribution of AMR pathogens and environmental pollution, our experts called on a joint effort at improving poultry management, waste treatment and adequate disposal or reuse.
Dr. Ayangbenro opined that everyone has a role to play, especially through prudent antibiotics use in livestock. Dr. Somorin further proposed implementation of appropriate composting to reduce environmental contamination and risks of transmitting MDR bacteria, while Dr. Olajuyigbe suggested the need for law enforcement of rules for proper treatment and disposal to forestall indiscriminate disposal of poultry and other animal waste products.
In her own submission, Dr. Aminat Badmos, a microbiology Lecturer at Federal University of Agriculture, Abeokuta added that good hygienic practices are key to eliminating AMR in foods.
“The presence of AMR microorganisms in our agricultural systems and food chains is a potential route of exposure for everyone. Good hygienic practices in farming are a vital way in achieving food safety, it is also key to addressing antimicrobial resistance.”