Antibiotics, The Double-Edged Swords.

The first antibiotic was discovered by accident in 1928 by the bacteriologist Sir Alexander Fleming. Fleming was growing some bacteria on Petri dishes when he discovered white mold (fungus) had contaminated his samples. As he was about to toss them out, he noticed a unique pattern of growth on those plates: bacteria did not grow around the mold, there was a zone of clearing.

penicillium-zone-of-inhibition

Fleming hypothesized that the fungus has produced a “substance” that has inhibited the bacteria from growing. The fungus was identified to be Penicillium notatum and was later renamed Penicillium chrysogennum. The active inhibitor “substance” was named penicillin and thousands of other antibiotics have since been discovered.

In most developed countries, antibiotics are available via prescription only. However in some countries, these drugs are misrepresented as the magic potion that can eliminate all forms of discomforts, ranging from headaches to sprained ankles, because these drugs are readily accessible as over-the-counter medicines. Commonly prescribed for bacterial and some fungal infections, antibiotics are no use against viruses. This is a frequently overlooked fact. “Self-prescribing” laymen may purchase antibiotics for a common cold or influenza, not knowing the serious repercussions.

Antibiotics generally work by selectively targeting the invading pathogen, and leaving our cells unharmed. The dose of antibiotics prescribed is carefully calculated to effectively rid the body of the pathogen. Hence, the label always reads “Complete Course”. Failure to abide by this instruction results in incomplete eradication of the pathogens, and the remaining ones will develop resistance to that antibiotic. These rogue cells will then go on to reproduce more copies of themselves and will eventually become harder to treat in future.

antibiotic-resistance

A notable example of resistant would be Staphylococcus aureus. This bacteria is commonly found on moist skin and in the nostrils of about 24% of the human population. It also grows very well in the upper respiratory, gastrointestinal and urogenital tracts of humans.

Commonly called as “staph infections”, when there is a breach in the skin, S. aureus can travel into deeper tissues and cause potentially fatal systemic infections. In 1945, up to 90% of staphylococci were sensitive to penicillin, but today less than 5% are susceptible.

By the fascinating phenomenon called evolution, bacteria have developed clever ways to resist antibiotics. For example, some microbes produce chemicals that can deactivate the antibiotics, while others may change their cell structure thereby preventing the drug from attaching to their surface or entering the cell.

These resistance mechanisms have alarmed the healthcare fraternity because they show that infections that were treatable previously, will soon be impossible to cure.

A recent case was reported in Nevada, US of a 70-year old woman who died of a bacterial infection after visiting India for a surgery. The woman had contracted a notorious bacteria called Klebsiella pneumoniae which was resistant to 26 types of antibiotics known to man. Which means, this bug is chemically indestructible.

India and China are home to a number of pharmaceutical plants manufacturing antibiotics. As a result of lax laws and regulations, these plants discharge chemical effluent wastes, containing active antibiotic ingredients, into the surrounding environment, which then leak into the soil and water systems. Such irresponsible actions inevitably create environmental “reservoirs” of resistant bacteria. A 2007 study published in the Journal of Hazardous Materials found the presence of the antibiotic ciprofloxacin in amounts 1000-fold greater than the toxic level to some bacteria (1). Such constant and excessive exposure to these antibiotics, cause the resident bacteria to develop immunity to the drugs, making them “superbugs”. Because bacteria have no sense of national boundaries, the resistant bacteria traverse the globe with relative ease.

India is one of the largest contributor to the world’s antibiotic resistance crisis due to the rampant overuse/misuse of antibiotics in human medicine and farming, and negligent practices by its manufacturing plants. A paper published in the Lancet in 2013 estimates that, in India alone, at least 58000 babies die annually from infections caused by resistant bacteria, which were previously treatable (2).

We should not forget that antibiotics have saved millions of lives since their discovery. But it is everyone’s responsibility to use them properly to prevent the spread of resistance. As much as it is the responsibility of the healthcare professionals to prescribe suitable antibiotics only when appropriate and to educate the patients of proper use, the public should also be responsible and follow instructions. The frequency of intake of prescribed medicines must be adhered to even if it is inconvenient. Skipping of dose will reduce the efficiency of the drug as it allows less sensitive bacteria to grow and spread.

References

(1) D.G. Joakim Larsson, Cecilia de Pedro and Nicklas Paxeus. (2007). Effluent from drug manufactures contains extremely high levels of pharmaceuticals. Journal of Hazardous Materials. 148 (3).

(2) Ramanan Laxminarayan, Adriano Duse, Chand Wattal, Anita K M Zaidi, Heiman F L Wertheim, Nithima Sumpradit, Erika Vlieghe, Gabriel Levy Hara, Ian M Gould, Herman Goossens, Christina Greko, Anthony D So, Maryam Bigdeli, Göran Tomson, Will Woodhouse, Eva Ombaka, Arturo Quizhpe Peralta, Farah Naz Qamar, Fatima Mir, Sam Kariuki, Zulfi qar A Bhutta, Anthony Coates, Richard Bergstrom, Gerard D Wright, Eric D Brown, Otto Cars. (2013). Antibiotic resistance—the need for global solutions. The Lancet Infectious Diseases Commission. 13(12).

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