The overuse of antibiotics in food animals

        Recently, I read an article published in Your Health, by Dr Mpokigwa Kiputa, entitled; Powercef: Medicine widely used and ‘abused’ in TZ.

This prompted me to write this article and put the issue of antibiotic resistance in perceptive as an expert on infectious diseases.

Rapidly emerging resistant bacteria threaten the extraordinary health benefits that have been achieved with antibiotics.

This crisis is global, reflecting the worldwide overuse of these drugs and the lack of development of new antibiotic agents by pharmaceutical companies to address the challenge.

New resistance mechanisms are emerging and spreading globally, threatening our ability to treat common infectious diseases, resulting in prolonged illness, disability, and death. Without effective antibiotics for prevention and treatment of infections, medical procedures such as organ transplantation, cancer chemotherapy, diabetes management and major surgery (for example, caesarean sections or hip replacements) becomes a risk.

Antibiotic resistance increases the cost of health care with lengthier stays in hospitals and more intensive care required. Antibiotic resistance is endangering the achievement of the Sustainable Development Goals.

What is antibiotic resistance?

Antibiotic resistance occurs when an antibiotic has lost its ability to effectively control or kill bacterial growth; in other words, the bacteria are “resistant” and continue to multiply in the presence of adequate levels of an antibiotic.

The global action plan sets out five strategic objectives to address this global issue:

1. To improve awareness and understanding of antimicrobial resistance.

2. To strengthen knowledge through surveillance and research.

3. To reduce the incidence of infection.

4. To optimize the use of antimicrobial agents.

5. Develop the economic case for sustainable investment that takes account of the needs of all countries, and increase investment in new medicines, diagnostic tools, vaccines and other interventions.

In a developing country like Tanzania and most other countries in sub-Saharan Africa where burden of illness is huge, the cost of health care provision is increasing and to implement the above strategies is next to impossible.

Laboratories services are not widely available hence microbial diagnosis is minimum and empirical treatment with antibiotics is widely practiced.

In this scenario it is difficult to optimize the use of antibiotics and the latest antibiotics are available as over the counter drugs (without prescription).

This is an honest view and a reality, sub-Saharan Africa and perhaps other developing countries in the world will not be able to address this issue.

An untold phenomenon

However there is something more to antibiotic resistance. In the developed world the above outlined five strategies are being stringently followed.

For example in USA, can you buy antibiotics without a prescription?-the answer is a definite ‘No’. They have a good surveillance and infection control system especially hospital related infections and awareness about this is high.

If they are doing all this then the question is, ‘why are they registering cases of antibiotic resistance?’

This is a valid question and perhaps the major cause of antibiotic resistance is not captured by these five strategies.

The major cause is extensive agricultural use.

In the developed world, antibiotics are widely used as growth supplements in livestock.

An estimated 80 per cent of antibiotics sold in the US are used in animals, primarily to promote growth and to prevent infection.

Treating livestock with antimicrobials is said to improve the overall health of the animals, producing larger yields and a higher-quality product.

So its all about profits from the livestock industry and is primarily driven by human greed for more wealth.

Humans ingest the antibiotics used in livestock when they consume food.

The transfer of resistant bacteria to humans by farm animals was first noted more than 35 years ago, when high rates of antibiotic resistance were found in the intestinal flora of both farm animals and farmers. More recently, molecular detection methods have demonstrated that resistant bacteria in farm animals reach consumers through meat products.

This occurs through the following sequence of events:

1) Antibiotic use in food-producing animals kills or suppresses susceptible bacteria, allowing antibiotic-resistant bacteria to thrive.

2) Resistant bacteria are transmitted to humans through the food supply.

3) These bacteria can cause infections in humans that may lead to adverse health consequences.

The agricultural use of antibiotics also affects the environmental microbiome. Up to 90 per cent of the antibiotics given to livestock are excreted in urine and stool.

It is then widely dispersed through fertilizer, groundwater, and surface runoff.

In addition, tetracyclines and streptomycin are sprayed on fruit trees to act as pesticides in the western and southern United States.

While this application accounts for a much smaller proportion of overall antibiotic use, the resultant geographical spread can be considerable.

This practice also contributes to the exposure of microorganisms in the environment to growth-inhibiting agents, altering the environmental ecology by increasing the proportion of resistant versus susceptible microorganisms.

Countries like Tanzania where the livestock industry is relatively underdeveloped, our contribution to this epidemic maybe minimal.

It’s the same case of global pollution phenomenon and climate change. The developed countries are the major polluters but we also face the consequences of the resultant climate changes.

Unfortunately our Ministers of Health sign on dotted lines while in Geneva on the global action plan. Who will pay the costs of implementing these strategies?

Some few dollars are given to do surveillance work but it’s our population that pays the price while we never gained anything from their livestock industry. This is the real global public health politics.

Through research, new effective antibiotics will be discovered and innovative novel drug formulation using ‘Cochleate Nano’ particles technology for targeted delivery is the future but this will come with a high cost.

The sub-Saharan countries will not be in a position to pay for these advances. We are facing a double epidemic of infectious and non-communicable diseases including cancers.

I am afraid I do not have a practical solution at this stage-just hope that something innovative will be discovered with time to effectively address this global health crisis.

Meanwhile lets try to improve our economic and become a middle-income country so as to provide better health care in the future.

Furthermore emphasis should be on preventive measures to avoid NCDs and infections.