ANTI MICROBIAL RESISTANCE (AMR)
Microbes are living organisms that multiply frequently and spread rapidly. They include bacteria, viruses, fungi and parasites. These microbes are constantly evolving enabling them to efficiently adapt to new environments. Anti Microbial Resistance (AMR) is the ability of microbes to grow in the presence of a chemical (drug) that would normally kill them or limit their growth. This behavioral change in microbes occurs owing to genetic mutations and this resistance is transferred among the microbes. AMR makes it harder to eliminate infections from the body as existing drugs become less effective. AMR also increases the duration of treatment, thereby elevates the treatment costs for beleaguered patients. Instances of AMR are widespread in human medicine: in bacteria e.g. MDR-TB (Multi Drug Resistant Mycobacterium Tuberculosis), MRSA (Methicillin Resistant Staphylococcus Aureus), VRE (Vancomycin Resistant Enterococi), MDR-NG (Multi Drug Resistant Neisseria gonorrhoeae); in viruses e.g. HIV (Human Immunodeficiency Virus); in protozoa e.g. malaria and in fungi e.g. Candida.
INDISCRIMINATE USE OF ANTIBIOTICS
One of the prime reasons for AMR is the indiscriminate use of antibiotics in human and veterinary medicine. In both the disciplines antibiotics are often over-used and misused. The humans and animals are affected by similar pathogens including bacteria, protozoa, fungi, parasites or viruses. In fact, about 60 percent of human pathogens are of animal origin. The same classes of antibiotics are used against these microbes in both animals and humans, of course at different doses in tune with their body weights and physiological peculiarities. It is estimated that the total amount of antibiotics used in veterinary medicine is far higher than in human medicine. This is because in animals and birds antibiotics are used not only for therapeutic purposes to treat various infectious diseases but also at sub-therapeutic levels to promote better growth and development in them. In fact, the practice of using antibiotics at sub-therapeutic levels to achieve better gains is quite common in poultry birds, particularly in broiler chicken which have a life cycle of just 42 days.
At various instances antibiotics are needless in humans and animals. Simple respiratory tract or gastro-intestinal tract infections of viral nature which are self limiting don’t require antibiotics. Similarly various ailments like debilitating and deficiency diseases which have nothing to do with infections don’t need these drugs. When, where, why and how to use antibiotics in veterinary and human medicine is important. Only a qualified and competent doctor (medico or veterinarian) can answer these questions and prescribe these drugs judiciously in appropriate dose and duration. Authorities and some people do realize that antibiotics in human medicine have to be taken only on the prescription of qualified medicos. This often hits the headlines. The above mentioned GK headline is a case in point. But they don’t realize that antibiotics used in veterinary medicine have a direct bearing on human health in the long term. It often gets unnoticed. Irrational self-medication of antibiotics by animal owners is rampant in veterinary sector. The misuse of antibiotics in veterinary is a typical feature of developing countries.
Indiscriminate use of antibiotics in animals leads to the development of the AMR in microbes as the same classes of antibiotics are used in both humans and animals. Globally, the tripartite alliance of WHO, FAO and OIE (world animal health organization) under the concept of “One Health” is striving to minimize the indiscriminate use of antibiotics both in human and veterinary medicine. There is an apprehension that a day in future may come when the world will be left with no medicines to treat infections because of AMR. Therefore the alliance advocates the research to develop newer classes/generations of antibiotics to combat these infections. Furthermore, the alliance lays stress on the discovery of preventive measures like vaccines against all infectious microorganisms to minimize the need of antibiotics. It also stresses on better bio-security measures to minimize the infections, thereby lessen the use of antibiotics.
Antibiotics are used in veterinary to treat various infectious diseases. Injections of antibiotics are often given in the muscular portions of animals. When animals are slaughtered or milked, the drugs naturally find a way via meat and milk in human food chain. The antibiotics have a milk or meat ‘withdrawal period’ which has to be followed in the strict sense to prevent the drug residues from being transferred to humans via milk or meat. Unfortunately these guidelines often indicated on the label of antibiotic vials are seldom followed owing to the lack of awareness among the masses. The result is, in addition to the AMR in microbes, these antibiotic-residues pass on to the humans via milk, eggs and meat. Proper milk and meat withdrawal period of antibiotics as per the label has to be followed. In veterinary medicine the antibiotics have to be prescribed only by the qualified veterinary doctors. Over the counter (OTC) sale of antibiotics without the prescription of veterinarians has to be banned. Indeed, the use of antibiotics in animal husbandry has a direct bearing on human health. The sooner we realize it, the better it will be.http://www.greaterkashmir.com/news/opinion/the-impending-post-antibiotic-era/202641.html
Pharm.D @ SRIPMS-CBE-TN