When British scientist Alexander Fleming discovered penicillin from a fungus and this amazing substance was found to be an antidote for most bacteria, killing infections from gangrene to pneumonia, antibiotics seemed to have made our conquest over bacteria complete.
But having inhabited the planet for millions of years, these organisms were far from giving up so easily. They evolved into stronger and stronger strains capable of gradually resisting antibiotics.
How did this happen? In The Killers Within, authors Michael Shnayerson and Mark J. Plotkin explain the science of how bacteria work and become antibiotic resistant. We are told how antibiotics obliterate bacteria by targeting their cell walls and breaking them down. Bacteria multiply at an extremely fast rate and a single bacterial cell can, in fourteen hours, produce a population that equals the entire human population on earth. A few random mutations or changes in DNA in some of these bacteria can render it capable of resisting that drug. Once a few resistant bugs develop the ability to fight the antibiotic, they proliferate -- and soon a drug resistant bacterial strain is born. For instance, bacteria that were killed by penicillin eventually developed an enzyme that cleaved or destroyed penicillinís structure before it could reach the bacterial surface. New and semi-synthesized antibiotics soon followed penicillin, each creating resistant strains in the course of time. With such strains on the rise, scientists and doctors turned to combination therapies where two or more antibiotics were administered. It was thought that the odds of a bacteria developing mutation to two or more drugs was very small. Instead they unknowingly created multi-drug resistant strains, capable of resisting several antibiotics at the same time. Thus, modern medicine became somewhat akin to a race between scientists developing newer and newer drugs and bacteria acquiring mutations in their genes to overcome these drugs.
The best thing about this book is that the authors show us the various facets of this problem. How the bacteria evolve and what drug researchers must do as a next step to overcome them. The doctors, patients and their families who are desperate to try anything new that can contain infection. We also see how drug companies, having invested millions of dollars into research, are reluctant to withdraw a new drug that creates resistant and harmful bugs. And how administrative bodies such as the CDC and FDA must struggle through mounds of evidence before deciding whether to retain or remove any particular drug from use.
It is now well accepted in the scientific and medical fields that the answer to this problem of antibiotic resistance lies in stopping their excessive and extensive use for every imaginable illness. As the rampant use of penicillin as a general health powder has shown, antibiotic overuse leads to resistance even in harmless bacteria that inhabit our bodies turning them into our foes.
Another source of alarm is the dairy and poultry industry. The use of antibiotics in the animal fodder to promote growth has led to the development of antibiotic resistant strains in turkeys, pigs, sheep and chicken. Once these resistant animal bacteria enter the human system as food they transfer their resistant genes to human bacteria.
But as the authors tell us, there is hope yet, in the form of bacteriophages or organisms that can destroy bacteria. These organisms that were used in the erstwhile Soviet Union against some infections still need to be studied in more detail and it might be years before they can emerge as drugs against bacterial infections. In the meantime, there is a need for scientists, doctors, drug administrative bodies and drug manufacturers to work together to reduce indiscriminate antibiotic use.