With stories about antibiotic-resistant bacteria increasing daily, a new chapter may be starting due to widespread antibiotics misuse. Research conducted at the University of Exeter in England has found that e. coli bacteria, when exposed to doxycycline over a period of a few days, go beyond developing resistance – the bacteria thrive on the antibiotic.
Over a four-day period, e. coli were grown in a liquid environment similar to human blood and subjected to eight rounds of Doxycycline. During the experiment, a number of mutations occurred, one of which is linked directly to resistance to antibiotics. However, a new and unexpected development emerged that resulted in faster and stronger growth.
Under normal conditions, e. coli produce an external biofilm that facilitates its spread, but in a controlled and predictable manner allowing effective treatment to control or stop its spread. After dosing with Doxycycline, however, the bacteria essentially deleted this feature from its genome, allowing it to direct more of its energies to faster reproduction and in larger numbers, which it did at a prolific rate. More worrisome was that after antibiotic exposure was discontinued, the mutation did not reverse or disappear – it had become permanent.
Fears about superbugs are not unfounded, as more and more cases of strains immune to traditional antibiotics are emerging, posing a serious problem for worldwide health. When a germ cannot be destroyed using existing medications, it can quickly spread and reach epidemic proportions with deadly consequences. The race is then on to discover or create a new form of treatment that will stop the disease.
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How basic antibiotic resistance happens. Source: cdc.gov |
Part of the antibiotic resistance problem, researchers believe, is because of the now widespread availability and misuse of antibiotic medications. To some extent, it is due to random and indiscriminate self-medication, but there is a greater problem at work. Old or expired doses are often disposed of in private septic or municipal water and sewage systems, allowing them to penetrate the groundwater or enter various waterways. Because e. coli and other bacteria exist in nature, this provides a greater opportunity for exposure and, subsequently, mutational evolution.
This does not mean that antibiotics should be discontinued, or that all antibiotics contribute to the development of superbugs. The study discussed focused only on Doxycycline. Indeed, drugs such as Doryx and others are invaluable in fighting disease and infections. One thing that can be done to lessen the likelihood that resistant strains develop is to curtail antibiotics misuse by using them only for their prescribed purpose and dispose of them in such a way that they cannot enter and contaminate the environment.
