With no new class of antibiotics having been developed for the past three decades, and a pipeline far from robust, the future of antibacterial therapy looks grim
Many of us would rely on our personal experiences to infer that antibiotics are losing their effectiveness. They are no longer as useful as they used to be in the past. While on one hand, medical science is advancing, on the other we see common infections becoming difficult to treat. At times, doctors prescribe multiple antibiotics at the start of treatment and later have to switch to other antibiotics, which are often expensive or have more side-effects. The outcome of surgical procedures is strongly linked to the success of antibiotics. It is not uncommon to learn of instances where the surgery went off well but the patient succumbed to an untreatable infection.
Amit Khurana
Antibiotic resistance is the phenomenon we are talking about. A large number of illnesses, deaths and economic losses are attributed to it in several countries. It is now considered a grave threat to public health across the globe and in India. Simply put, when infection-causing bacteria is not killed by an antibiotic that was effective earlier, the bacteria continue to thrive. Treatment options shrink further when multiple antibiotics fail to kill the bacteria. This trend has been reported from across the world. For example, Escherichia coli, Klebsiella pneumoniae and Shigella, which cause infections of gut, blood stream, urinary and respiratory tract are getting resistant to flouroquinolones, cephalosporins and carbapenems. The problem is not limited to only these. It extends to more kinds of bacteria and a greater number of antibiotics. It’s about multiple or all antibiotics becoming ineffective. With no new class of antibiotics having been developed for the past three decades, and a pipeline which is far from robust, the future of antibacterial therapy looks grim. It is no wonder then that the World Health Organization (WHO) considers a post-antibiotic era as a possibility in 21st century.
Awareness week
For the first time, this year (November 16−22) is being observed as World Antibiotic Awareness Week. This article also attempts to focus on the animal side of story i.e. the (mis)use of antibiotics in food-producing animals for two reasons. First, it is less known to us in India, as also evident from latest WHO report on awareness. Second, it is regarded as a significant contributor to the overall problem.
Getting to know what leads to the emergence and spread of this phenomenon is the first step towards understanding why resistance emanates from animals. An antibiotic presence puts pressure on bacteria to select for resistance, a natural process. This is akin to survival of the fittest. The ones that adapt, survive. However, misuse of antibiotics accelerates the emergence of resistance. For example, in the case of a routine administration of low-dose antibiotics in order to promote growth in chickens or even a person having an incomplete course of antibiotics, could result in more bacteria adapting and surviving than getting killed. The traits of resistance pass on vertically and become similar to other kinds of bacteria nearby, most often through horizontal transfer of genetic material, which adds to reservoirs of resistant-bacteria in humans and the environment. Quite like a chain reaction, both selection and transfer of resistance accelerates at places which are microbially rich and directly or indirectly exposed to antibiotics, particularly at lesser concentration and for longer durations. These places facilitate a continuous interplay between the antibiotics and bacteria. These include human and animal gut, soil, litter and farm manure, water bodies and sewage. So, just like a hospital, a farm which uses antibiotics to raise poultry or fish is a potential source of resistant-bacteria that can transfer to agricultural fields and affect vegetarians too. Similarly, sewage and water bodies that get waste from households and antibiotic manufacturing firms are other possible reservoirs.
With its policy in 2012 to contain antimicrobial resistance, India started focussing on controlling the misuse of antibiotics in people, but with limited progress. A lot needs to be done as well to control misuse in animals. A study in 2014 by the Centre for Science and Environment on antibiotic residues in chicken meat, pointed towards the rampant use of antibiotics for non-therapeutic reasons such as growth promotion and mass disease prevention in poultry. Highlighting the regulatory gaps, and consistent with how the world is handing animal antibiotic misuse, CSE suggested a series of measures.
In the end, India needs to work towards prohibiting the misuse of antibiotics. Systems for monitoring trends of antibiotic use and integrated surveillance of resistance need to be created. Poultry farmers must also be encouraged to reduce the use of antibiotics and move to safer alternatives. It should consider adopting these as part of its national plan to be submitted to WHO.
Clearly, antibiotics are to be handled with care. They are a global “public health good” and need to be preserved. With projected high antibiotic use in food-producing animals in India, we cannot afford to gloss over the issue and be complacent.
(Amit Khurana is Programme Manager, Food Safety and Toxins, Centre for Science and Environment.)
