The use of antibiotics has spurred modern medicine into what we know today. However, antibiotic resistance has caused a crisis within our society. Each year, about 25 000 deaths are attributed to drug resistant infections in Europe alone, in addition to the 1.27 billion dollars lost in hospital and outpatient costs and treatment failures (McKenna, 2011). Due to the decreasing amount of novel antibiotics entering the health care system, a high amount of strain has been placed on the medical community as antibiotics become less and less effective.
Due to mutation and natural selection, bacteria are naturally predisposed to gain resistance to antibiotics over time, but there are specific factors which cause resistance to occur at a faster rate (Larson, 2007). Due to the widespread availability of antibiotics, antibiotic misuse has become more and more common, caused by inappropriate self-prescription, which has been shown to be a factor in inducing drug resistance (BMJ, 2010). Self medication of antibiotics is common in large portions of the U.S. population, especially in immigrant populations from where antibiotics are also offered without prescription. This problem also persists in many other parts of the world. A 2005 study showed that 72% of Nigerian students self-prescribed drugs for diarrhea, where 80% of those used antibiotics, and 45% used more than one (Larson, 2007). In these cases, it is possible that bacteria within the individual’s body mutate to become resistant to the antibiotic. The resistance gene can then be shared between all surrounding bacteria in 2 ways when an infection occurs (BMJ, 2010): though cell-to-cell contact (conjugation) or by releasing the gene in the form of a plasmid, which can then be accepted by other bacteria (transformation). Sharing genes in this way is known as horizontal gene transfer.
The main issue regrading antibiotic resistance is the method in which they are currently used within society. Currently, antibiotics simply act as chemicals that perform the function of either killing bacteria or inhibiting bacterial growth. In nature, antibiotics can be found as natural parts of organisms, such as in the actinomycetes, which form a symbiotic relationship with leaf cutter ants. The antibiotics synthesized by the actinomycetes naturally evolve as a part of the evolutionary arms race between organisms (Currie, 1999). In this way, the inevitable failure of the isolated antibiotic used in modern medicine is immediately apparent. It does not have the same evolutionary abilities as the organism it seeks to destroy.
A key example of antibiotic resistance is β-lactamase, an enzyme responsible for resistance to β-lactam antibiotics, such as penicillin. Because the gene is so common, many bacteria presently have some modified version of the catalyst that extends or specifies its spectrum of resistance (Davies, 2010). One modification of β-lactamase, known as CTX-M, found in the 1990s, was the first enzyme found to be significantly resistant to cephalosporins (Hawkey, 2009). The CTX-M gene is found to be highly efficient at horizontal gene transfer and mutation, and has become an epidemic that is affecting us today.
As the threat of a world without antibiotics looms over society, several organizations are trying to contain the threat through a variety of proposals and solutions. The Canadian Institutes of Health Research has developed the Antibiotic Resistance Initiative which provides funding for research in novel alternatives to antibiotics, such as phage therapy (CIHR, 2009). It is possible that further research into species such as the actinomycetes may shed some light on the synthesis of artificial antibiotics. In addition, the World Health Organization issued its Global Strategy for Containment of Antimicrobial Resistance, which seeks to call health policy makers to reallocate and restrict antibiotic use within their countries (APUA, 2012). Antibiotics are essential to modern medicine. Changes must be made to their use and distribution to work towards a sustainable future before it is too late.
Works Cited:
APUA, 2012. General Background: What can be done about Antibiotic Resistance? [online] Available at: <http://www.tufts.edu/med/apua/about_issue/what_can_be_done.shtml> [Accessed September 27, 2012]
CIHR, 2009. About the Antibiotic Resistance Initiatives. [online] (Nov 23, 2009) Available at:<http://www.cihr-irsc.gc.ca/e/40485.html> [Accessed September 25, 2012]
Costelloe, C. et al., 2010. Effect of antibiotic prescribing in primary care on antimicrobial resistance in individual patients: systematic review and meta-analysis. Bmj, 340(may18 2), pp.c2096–c2096. Available at: http://www.bmj.com/cgi/doi/10.1136/bmj.c2096 [Accessed September 22, 2012].
Currie, C.R. & Scott, J.A., 1999. Fungus-growing ants use antibiotic-producing bacteria to control garden parasites. , 398(April), pp.701–705.
Davies, J. & Davies, D., 2010. Origins and evolution of antibiotic resistance. Microbiology and molecular biology reviews : MMBR, 74(3), pp.417–33. Available at: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2937522&tool=pmcentrez&rendertype=abstract [Accessed September 22, 2012].
Hawkey, P.M. & Jones, A.M., 2009. The changing epidemiology of resistance. The Journal of antimicrobial chemotherapy, 64 Suppl 1, pp.i3–10. Available at: http://www.ncbi.nlm.nih.gov/pubmed/19675017 [Accessed September 23, 2012].
Larson, E., 2007. Community factors in the development of antibiotic resistance. Annual review of public health, 28, pp.435–47. Available at: http://www.ncbi.nlm.nih.gov/pubmed/17094768 [Accessed September 20, 2012].
Michel, B., 2005. After 30 years of study, the bacterial SOS response still surprises us. PLoS biology, 3(7), p.e255. Available at: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1174825&tool=pmcentrez&rendertype=abstract [Accessed September 23, 2012].