Elmer W. Koneman: Tuberculosis and the evolution of ‘superbugs
Re. by David Woodland, SDN, June 6
David Woodland’s recent account of the ongoing world-wide scourge of tuberculosis is a significant step forward in making the public aware of the spread of this “white plague.” It is formidable for us living in the United States, and in other well-developed countries, to comprehend that an estimated 4,000 people each day are dying world-wide from tuberculosis. Woodland explains very well the development of drug resistance that has evolved with this bacterium, with its rapid rate of replication, its thick protein outer coat protective against penetration of many antibiotics, and humans infected with reticence in completing a full course of therapy.Yet, tuberculosis is only one among many bacteria that have been involved in plagues throughout history, past and present. The Industrial Revolution and opening up of trade routes during the 13th and 14th centuries, with introduction of hordes of rats and their pestis-infected fleas led to the massive spread of the “black death” in congested and filthy population centers. Wars and conflicts, where soldiers have been closely assembled in unsanitary environments, have also led to massive spread of infections. The bacterial causes for these outbreaks were not known until the late 19th century when Robert Koch discovered Vibrio cholera as the culprit in his investigation of contaminated water supplies, causing pandemics in Egypt and cities in Asia Minor.Yet, even in our modern scientific, sophisticated societies, bacterial plagues remain, although better controlled. The pumping of contaminated pond and stream water into environmentally controlled water tanks led to the proliferation and distribution of Legionella bacteria into air conditioning ducts, leading to widespread pneumonia among elderly sleeping legionnaires attending the 1976 convention in Philadelphia, fatal for many. Just last year, a minor similar outbreak occurred in a posh hotel in Las Vegas. What about the recent outbreak of listeria infection from the ingestion of contaminated cantaloupes, of all things; or the recent emptying of grocery meat shelves to curb outbreaks of E. coli and other bacteria. Currently, the majority of staphylococci recovered in hospital environments are drug resistant, the so-called “MRSA” strains.Bacteria are complex forms of living matter, the behavior of which is dependent upon the life sustaining action of a single chromosome, with complex arrangements of DNA strands that provide for production of nutrients and, unfortunately, toxins as well. What may be a non-threatening environment in a natural niche, or as commensal within a plant or animal, becomes a pathologic agent when transferred into another host, particularly into humans. When bacteria are not completely controlled, mutations occur that either makes them more aggressive within the new host; or, that become “superbugs,” resistant to a variety of anti-bacterial agents that continue to be developed, often with only temporary effect. The unfortunate conclusion is that, as evidenced by the continuing spread of tuberculosis and the habitation of hospital environments with MRSA, bacteria will remain in our environment, either as harmless commensals, or as aggressive mutants resulting in morbidity or mortality. Prevention is the only answer to curbing infections and outbreaks, often compromised by economic considerations, such as the raising of animals in enclosed, often unclean environments. The indiscriminate use of antibiotics, such as used for empiric therapy in humans, or their massive use in feeds to protect animals while being raised for slaughter are other factors. As concluded by Woodland in his article, “we all have a stake in resolving this global health crisis.” This superbug “crisis” in various forms, remains also local, regional and national.
Support Local Journalism
Support Local Journalism
As a Summit Daily News reader, you make our work possible.
Now more than ever, your financial support is critical to help us keep our communities informed. Every contribution, no matter the size, will make a difference.
Your donation will be used exclusively to support quality, local journalism.