Antimicrobial resistance: a ticking time bomb

     

One of the landmark scientific achievements of the 20th century has been the discovery of antibiotics. Antibiotics have revolutionized healthcare and have helped healthcare professionals save precious human and animal lives for centuries. However, antibiotics have now become victims of their own success. Due to their non-judicious and blind use, we now face a widespread occurrence of antimicrobial resistance (AMR). AMR occurs when changes in bacteria cause the drugs used to treat infections to become less effective. Perhaps we are now facing the 21st century’s biggest public health challenge in the form of AMR. The emergence of “superbugs,” or antibiotic-resistant pathogens, now contributes to the emergence of diseases that were for a while well controlled. For example, emergent bacterial strains causing tuberculosis (TB) that are resistant to previously effective antibacterial treatments pose many therapeutic challenges. Every year, nearly half a million new cases of multidrug-resistant tuberculosis (MDR-TB) are estimated to occur worldwide. It is estimated that annually there are 12.7 million deaths as a direct result of antimicrobial resistance (AMR), which means that AMR kills more people than HIV/AIDS or malaria. We are now at a point where many of the drug treatment breakthroughs of the last century could be lost through the spread of antimicrobial resistance. As a result, many infectious diseases may become uncontrollable and could rapidly spread throughout the world. According to the WHO, the main causative reasons are underuse, overuse, and misuse of antibiotics; a lack of quality medicines (by exposing patients to suboptimal concentrations of anti-microbials); and animal husbandry.

Antibiotics are used in animal production to protect animal and public health (e.g., to prevent and control zoonosis) as well as subtherapeutic growth promoters. Due to a lack of data, the annual consumption of antimicrobials by the animal husbandry sector is not known precisely. However, according to some estimates two third of the antimicrobials are used in the animal production sector. With the bulk of consumption in the poultry and pig sector, it is important to consider that prudent therapeutic uses of antimicrobials in animals are essential for animal health, welfare and productivity and contributes to food security, food safety and public health, thereby protecting livelihoods.

With growing demand for foods of animal origin like meat and milk, non-therapeutic and sub-therapeutic use of antimicrobials has spiked in the livestock sector. And this leads to growing resistance to antimicrobials, which can render treatments ineffective, increase the severity of disease, and cause heavy economic losses. In addition to this, antibiotic drug residues can transmit through the food chain and spill over into the environment, increasing the burden of resistance. Moreover, drug-resistant pathogens can be transferred from confined animal feeding operations to the general human population via food, presenting another kind of serious public health risk.

The developing world paints a frightening picture, with antimicrobial use largely unregulated. Add to that the fact that antibiotics are widely and uncontrollably used, and patients frequently do not complete a full course of treatment if they cannot afford it. Another problem in developing countries is the quality and potency of antimicrobial drugs. In developing countries, laboratory diagnostic facilities are scarce, and this has led to the introduction of empiric, pragmatic, and problem-oriented management strategies for the administration of antimicrobial drugs. Inevitably, this results in overtreatment.

In order to tackle AMR, the first step would be to determine the true burden of resistance, and this presents a major challenge in view of the lack of data and absence of systematic surveillance. We don’t have comprehensive global estimates of the effects of AMR on incidence, death, hospital length of stay, and healthcare costs for various pathogen-drug combinations in the human and veterinary medical sectors.

A multi-pronged strategy is required to preserve antibiotics for future use. Such a strategy should focus on surveillance, legislation, the development of diagnostic networks, sensitization of communities and stakeholders, and working towards sustainable animal agriculture. States should consider highly regulating the use of antimicrobials in the human and veterinary sectors. The non-therapeutic use of antimicrobials (the use of antibacterials as growth-promoting agents in animal agriculture) should be ended, and restrictions should be imposed on the use of antibiotics in food animal production. To ensure appropriate antimicrobial use, developing countries’ laboratory infrastructure must be prioritized. Doctors, veterinarians, and the general public should be educated on the prudent use of antimicrobials.

In the animal agriculture sector, to support production and prevent and control diseases, we need novel and safer alternatives to AGPs (antimicrobial growth promoters). This will be a critical component of our efforts to alleviate poverty and world hunger on one hand, and it will also ensure that standard treatments remain effective and infections don’t persist and spread to others.