If you have administered antibiotics to the birds, you should throw away the eggs. This does not make economic sense, and even the disposal of the eggs will be a problem. Most farmers just go ahead and sell their produce oblivious of the health risk they pose to humans who will consume the produce
In 2019, about 1.3 million deaths globally were attributed to antimicrobial resistance infections, a recent WHO study estimates.
Africa has the highest mortality rate from AMR infections, with 24 deaths per 100,000 attributable to AMR.
Scientists at the International Livestock Research Institute are now seeking an alternative treatment for bacterial poultry diseases.
In Kenya, poultry farmers use antibiotics to treat bacterial infections to improve the growth and production of poultry.
However, antibiotics have a number of disadvantages.
Zachary Munyambu from Ngoigwa, Thika in Kiambu county, has been a poultry farmer for more than 10 years.
He says antibiotics are vital for controlling diseases and ensuring healthy chickens. However, the drugs are expensive and contribute to the high cost of poultry farming.
Munyambu says some diseases like Newcastle Disease can wipe out a whole flock of birds. Thus, a farmer may need to use antibiotics to treat secondary bacterial infections resulting from the disease.
“Farmers use antibiotics to protect their chicken from some infections but they are expensive and require proper knowledge of how to apply them. However, the challenge is that some farmers do not observe some of procedures such as the withdrawal period,” he said.
According to an expert, as a viral disease, Newcastle Disease cannot be treated with antibiotics. So, where necessary, some farmers use antibiotics to treat secondary bacterial infections that result from the disease.
Even so, some farmers may also not know what the cause of the disease is - whether viral or bacterial, and may mistakenly use antibiotics for a viral disease, which will be ineffective and can contribute to antimicrobial resistance (AMR).
Munyambu explains that a farmer is supposed to wait for at least seven to 14 days after giving antibiotics to chickens before selling or consuming them.
But because farmers do not want to make losses, they opt to sell the chickens irrespective of when they administered the antibiotics, he says.
“If you have administered antibiotics to the birds, you should throw away the eggs. For example, a farmer who has about 20,000 birds may be forced to throw away about 600 trays per day. This does not make economic sense, and even the disposal of the eggs will be a problem,” Munyambu says.
“Most farmers just go ahead and sell their produce oblivious of the health risk they pose to humans who will consume the produce.”
Munyambu, who is the coordinator of Kiambu Poultry Farmers’ Cooperative Society, says he has 1,000 birds and in a week, he spends about Sh3,000 on antibiotics, or Sh12,000 in a month, which is not sustainable.
“Getting an alternative method of disease control and prevention will be a great relief for poultry farmers as it will help to bring down the cost of production,” he says.
According to the World Health Organization, an estimated 75 per cent of antibiotics administered are released into the environment and contribute to antimicrobial resistance.
Statistics from the Ministry of Agriculture and Livestock Development show that poultry farming represents approximately 30 per cent of the country’s total agricultural contribution to the gross domestic product.
An estimated 75 per cent of rural families keep chickens, with an average of 13 birds per household.
However, infectious diseases associated with poultry farming and egg production pose high risks to the poultry industry and to the health of farmers and consumers.
Angela Makumi, an expert in medical microbiology, says antimicrobial resistance is a growing concern in poultry farming.
So far, we have been able to select a few phages that will be included in the final phage cocktail product. However, in order to understand the behaviour of phages and the control of salmonella in chicken, the cocktail is currently in its trial stage
She says this mainly happens when the antibiotics are not used appropriately.
The drugs pose an increasing threat to both poultry and humans, hence, an urgent need to look for alternatives to antibiotics, Makumi adds.
A report released in 2021 by World Animal Protection ahead of World Antimicrobial Awareness Week showed that dairy (49.6 per cent) and poultry (38.9 per cent) farmers are the most frequent consumers of antibiotics.
The report indicated that even though there is knowledge of antibiotics and AMR, self-prescription, failure to complete prescribed dose and sharing of antibiotics were prevalent.
Makumi says the rampant use of antibiotics in poultry farming can cause bacteria to become resistant and of concern is resistance to clinically relevant antibiotics.
“Therefore, there is need to find alternatives to antibiotics for the prevention, treatment and control of bacterial infections affecting poultry. One of the alternative approaches is the use of bacteriophages,” she says.
Makumi is part of a team of microbiologists at ILRI in Kenya led by Dr Nicholas Svitek, a senior scientist in Molecular Virology and Immunology, that is working on phages as an alternative to antibiotics and reduction of drug-resistant nontyphoidal salmonella in poultry farms.
Phages are viruses that have the ability to target specific bacteria, infect bacteria, replicate within them, and eventually kill their susceptible host.
“Bacteriophages (phages) are viruses that infect bacteria, and they have been used and administered as a medicinal product even before the discovery of antibiotics. Phages can be found in natural and man-made environments, especially those in which their bacterial host thrives,” Makumi explains.
Salmonellosis is listed by the Food and Agriculture Organization as one of the bacterial diseases affecting chicken health and productivity and also causes food-borne infections in Kenya.
Globally, the use of antibiotics is largely unregulated.
This is worse in developing countries where the use of antibiotics for food and animal production to prevent, control and treat bacterial diseases, and also to accelerate the growth of animals is rampant.
Makumi says comparatively, Africa produces fewer antibiotics, but unregulated access and inappropriate use worsen antibiotic resistance.
She says after the discovery of antibiotics by Alexander Fleming in 1928, phage therapy was abandoned in the West but some countries like Georgia and Poland, which witnessed the birth of phage treatment, have continued to use it to date.
“When you give antibiotics to the chicken, you are supposed to observe a withdrawal period thereafter you can sell your produce," she says.
"The challenge with antibiotics is that farmers have to wait to sell their produce incurring losses during the waiting time and sometimes some farmers may not observe the withdrawal period, especially when selling meat products.”
The scientist adds that in phage therapy, there are no withdrawal periods and farmers who opt to use phages can sell or consume the eggs or meat unlike in the use of antibiotics.
Makumi says coming up with a phage product, which includes different phages targeting different strains of the same species of bacteria, can be quite challenging.
“So far, we have been able to select a few phages that will be included in the final phage cocktail product. However, in order to understand the behaviour of phages and the control of salmonella in chicken, the cocktail is currently in its trial stage,” she says.
This is an innovative collaborative project between Laval University in Canada and ILRI, funded through Canada’s International Development Research Centre and the UK government’s Global AMR Innovation Fund managed by the Department of Health and Social Care.
“We are currently at the trial stage of the product in poultry and this would take more time to study the pharmacokinetics and pharmacodynamics of the phage cocktail as well as start seeking regulatory approval from the Veterinary Medicines Directorate before we can disseminate it to the farmer,” Makumi says.
Edited by Josephine M. Mayuya