Mrs Victoria Olushola Adetunji is a professor of Food Safety, Food Microbiology and Veterinary Public Health at the Department of Veterinary Public Health and Preventive Medicine, University of Ibadan. She explains dangers associated with abuse of antibiotics in animal production and ways to avoid public health crises. FEMI IBOROGBA reports.
To curb the problem of abuse of antibiotics in animal production, especially in poultry, how can farmers be guided?
The first thing is to reduce the disease burden by proper farm management in term of proper waste disposal to reduce contamination in the environment. One major good waste management which has not been properly explored by farmers is biogas production. Essentially, biogas is the production of methane gas, a type of gas that can be used for cooking, and the feedstock for the biogas production is animal and farm wastes, including manure and plant waste.
Proper farm hygiene management includes cleaning of feeding troughs, biosecurity and all procedures to reduce disease establishment in the environment. Biosecurity involves control of traffic into the farm and when people come into the farm, their feet and arms are disinfected.
Is the abuse actually escalating cases of resistance in humans? Has evidence proven that?
Yes. Currently, we have 2019 reports by mails. We have 700,000 deaths that are attributed to antimicrobial resistance and there is a projection that by 2050, we are going to have 10 million deaths that would be attributed to anti-microbial resistance. So, there is empirical evidence that we are having a global problem with anti-microbial resistance.
Common drugs that are being used for bacterial treatment are no more effective because of the issues of anti-microbial resistance and we have empirical data in our labs; we do a lot of work with surveillance in bacteria of food borne pathogens and we are seeing an increase in resistance even to top notch generation drugs. The microorganisms are continuously being resistant to antibiotics. There is an issue with tetracycline. It is an antibiotic that has been seriously abused by the human medics and the Vets. I understand that even this antibiotic is sold in some markets in bolds; even in fish production they are used as prophylactics to prevent infections. Generally, this antibiotic is resistant to most foodborne pathogens, which is what we have seen in our laboratories in the current research that we have done.
Some people have been advocating the use of probiotics. What does it mean and how can farmers in Nigeria start to explore this?
A probiotic constitutes viable and beneficial organisms. We call these beneficial organisms because they are not pathogenic; they don’t cause disease per say. Most of them are lactic acid-producing and they aim at pathogens. We have empirical data that shows that probiotics can aim at listeria, which causes listeriosis. The consumption of probiotics reduces disease burden; it has been proven and reported several times.
The advantage of probiotics is that it does not bio-accumulate in the systems like the drugs or chemicals would do. The issue of residues is eliminated. Apart from the fact that it is able to control disease burden, it is a viable alternative to the use of antibiotics or antimicrobials generally.
Are stakeholders working or collaborating to promote the use of probiotics and is it affordable for farmers?
Probiotics are available in the markets. Before now, farmers used antibiotics as growth promoters and it has been banned, but farmers still use it as growth promoters.
Probiotics can be used as alternatives for these two purposes. My team has been interacting with farmers; we interacted with the poultry association and farmers, the day-old chick farmers, telling them the dangers of indiscriminate use of antibiotics, the danger to the public and encouraging them to use probiotics as alternatives.
We’ve started this and we want to continue this as a yearly interaction with the public. We also interact with the cattle traders. We’ve interacted with them, telling them about the danger of not adhering to withdrawal periods and the fact that when the public consume such meat, they are exposed to low doses of antibiotics, which eventually can predispose the consumers not just to antibiotics residues but to allergies because some individuals are allergic to certain antibiotics. When they take them in low doses, they have problems.
You mentioned withdrawal period which is also applicable in poultry production. The antibiotics instruction says withdraw for three-five days depending on the maker. Farmers hardly adhere to this. What can we do in the real sense?
In the real sense, I think the major thing we can do is awareness. Creating awareness like the campaign we did earlier. Secondly, at the abattoir, aside doing surveillance for the pathogens, there is need for us to test for antibiotic residues before meat is distributed to the public. Any meat/meat tissues that have residues of antibiotics should not be sold because we are endangering lives. A lot of cases are in hospitals.
Let me come home, one of my kids had issue with antibiotic resistance. She was ill and had pneumonia, running temperature, and various antibiotics were recommended and she wasn’t responding to any of them.
That brings to mind the need to do antimicrobial stewardship. It has to do with ensuring procedures, putting it and methods in place, to make sure that we are actually making a science-based recommendation before treatment, in terms of ensuring that the particular pathogens involved with the disease condition has been identified, and antibiotic sensitivity testing done, to know which antibiotic this organism is going to respond to.
But most vet and human doctors recommend antibiotics without doing proper scientific investigation. Those are issues we need to address through awareness among the veterinary and human doctors, and also the farmers.
It is said that organic antibiotics is not dangerous to human. With your knowledge in the industry, is it a viable means?
Yes. In the first place, by organic antibiotic, I think what you mean is natural antibiotics, natural herbs and plants. It is a viable alternative. I want to give some specific data based on the research we have done to show that it is viable. We have many herbs or plants locally that have antimicrobial properties. An example is alligator pepper, which is called (Ataare). You won’t believe it has an inhibitory factor against micro bacteria. If this seed is actually explored, it could be worked and improved upon, and presented in a way that it can be used by the public for the treatment and control of tuberculosis generally. Another example is Calotropis procera, which is called bomu bomu in Yoruba language. That is what is used in the processing of cheese. I have seen this in our lab to contain antimicrobial properties. Another example is the efirin, which also have antimicrobial properties. Most of our local spices have antimicrobial properties, but there is need to do further research for the quantity, the amount test needed, the concentration of the active ingredient that is having the antimicrobial property, there is need for research in this area.
Definitely, organic antimicrobials are viable area to be explored but there is need for the government to be involved in research and development in this area.
What do you suggest, considering the figure that about 700,000 deaths were attributed to antimicrobial resistance in 2019 alone?
I will want to extend the advice beyond just the farmers and the government. I will want to include individuals, because policy makers, health professionals, health care industries and the agricultural sector players have a role to play each.
Starting with the agricultural sector, we want to ensure the prevention and control of antibiotic resistance by ensuring that antibiotics are given to animals based on veterinary supervision. Currently, we have veterinary quacks, people that have not been trained in the recommendation or use of antibiotics, selling and administering antibiotics, and acting as consultants to farms. There is need to ensure that antibiotics are administered to animals only on their veterinary supervision.
Secondly, the use of antibiotics as growth promoters should be discouraged by farmers. I am aware that antibiotics are also incorporated into animal feeds. Alternatively, probiotics should be used as additives to these animal feeds instead of antibiotics.
Animals should also be vaccinated against diseases to reduce the need for antibiotics, because if animals are vaccinated appropriately, there is going to be reduction in disease burden. We also want to promote good practices in production and processing of food of animal origin. We have mentioned withdrawal period earlier, but there should be good practices in the processing of the products.
I am sure the one in Lagos is similar to the one here, but we have a standard abattoir now where slaughtering of animals is not supposed to be done on the floor anymore. There is a railing system, but the butchers are still slaughtering animals on the floor. There is need for a re-orientation and training to ensure that things are done properly.
Coming to individuals, they are expected to use antibiotics that are prescribed by certified medical practitioners. There is something now; when we feel down at home, we buy our drugs at counters, and so most times we just take antibiotics. I must warn that sometimes when you have high temperature, it may not necessarily be due to bacteria. It could be due to a viral infection, and when we are using antibiotics to treat such infections, we are actually predisposing ourselves to antimicrobial resistance because when we actually need other antibiotics, they would no longer be effective because they were used when there wasn’t any need for it.
I also understand that some individuals actually ask the practitioners to give them antibiotic which should be discouraged. Never share or use leftover antibiotic, judicious and appropriate use of the antibiotics even when it is recommended. That is, taking it appropriately according to the time prescribed (8hours or more) and then completes the dose.
Recommendation is normally for five days, some individuals stop after 3 days, which can contribute to antimicrobial resistance. I have talked about health professionals in terms of proper prescription that is scientific based, evidence based prescription, taking samples from patients to ascertain the cause of the illness and the appropriate antibiotics that should be used. We cannot leave out the policy makers; we need to have a robust national action plan to tackle antimicrobial resistance.
Feed millers include antibiotics and other things that are not recommended. What is your advice for them and the regulatory agencies monitoring them, like Standards Organisation of Nigeria (SON) and NAFDAC, because toll millers constitute the main chains?
I will start with the awareness of the danger. There is an adage that says when you throw a stone into a market, you never can tell, it might hit a member of the family. The danger of incorporating antibiotics into feeds is that poultry, cattle or fish farmers will use the feeds but the end users of the products (the public) are going to be affected. When the animals are consumed regularly, human beings become exposed to low doses of antibiotics.
Having done the awareness, there is need for enforcement by the regulatory agencies like NAFDAC; I know they are doing a lot. SON, I know, has a list of things it is doing well, but it needs to do more. I know NAFDAC does a lot of surveillance for pathogens, but I don’t know how much residues they work on.
NCDC has a unit that focuses on antimicrobial resistance and they have a weekly reporting system, but we need to do more extension work, getting to these farmers, feed millers and actually speaking to them, having contact with them, collaborating with them, and training them for possible alternatives.
Collaboration with the researchers in the university, with the food industries and the animal keepers; taking our findings to them and making it usable to them. That is what an extension is supposed to do. We need to build up the issue of our extension service in the country.