WHO sounded alarm bells about Anti Microbial Resistance (AMR) this past World Health Day on April 7th and the warning is not early. This was writ large for a long time. Excessive prescription of antibiotics and, that too, in high doses are making microbes change faster than the speed of drug research. WHO warned of an imminent ‘pre-antibiotic age’, when we will be stuck with a large number of different, but ineffectual, antibiotics.
The threat is especially severe for diseases that spread through the air, water or vector agents. It has long been predicted that TB will develop resistance and the conventional drugs will not work in normal doses. Very high doses may harm the patient more that the bacteria itself, or may have some severe side-effects.
Bacterial strains, like Escherichia coli (E.coli), have already been observed developing medicinal resistance at conventional antibiotic doses. E.coli can mutate with amazing speed. They can go through about 20 generations in four hours, given an aerobic (i.e. oxygen-rich) environment and enough food (glucose). Scientists have observed that about 200 generations are enough for a potentially deadly strain to develop, a feat that E.coli can achieve in 2 days.
Many antibiotics adhere to the bacterial cell wall and slowly break it down. Bacteria change (or, rather, evolve) their cell wall composition slightly disallowing the adhesion, thus become immune. A greater fear is the crossing of genes amongst different bacterial strains producing a strain to which the human immune system has no response. This happened in the case of SARS, although that was a virus at work. E.coli has frequently been observed to cross with highly resistant Salmonella strains.
Multi-drug resistant (MDR) strains are also emerging at an alarming pace. A staggering 440 000 cases of MDR-TB are reported annually causing 150 000 deaths in 64 countries worldwide, according to WHO.
AMR threatens a return to the pre-antibiotic era â€” Many infectious diseases risk becoming uncontrollable and could derail the progress made towards reaching the targets of the health-related United Nations Millennium Development Goals set for 2015.
The first response to this threat is the judicial prescription of drugs by medical practitioners. WHO called upon all who have any stake holding in the medical practice and requested for more responsible behavior. Citizens are also responsible for maintaining a healthy lifestyle.
Just as prevention is better than cure, an immune system is a better defense than any antibiotic.