On 9th of March I wrote about the "coming plague" as a euphemism for the evil that is latent in all of humanity. Today, I am reading the latest edition of New Scientist (24th March 2007) which has an article, called "The White Plague", about the emergence of a new strain of tuberculosis that is resistant to all drugs. It has been dubbed XDR-TB (Extensively Drug Resistant TB). The worst hit countries are China, India, Russia and South Africa but, it has also affected all the G8 countries (the world's wealthiest nations). The article says: "Now New Scientist has learned of the first known case of completely drug-resistant TB, in Italy." In fact, as at 12th March, 8 cases of XRD-TB have been diagnosed in Italy: 4 native Italians and 4 foreigners (from Eastern Europe, Africa and Latin America), and there have been 2 deaths. For those of you who read Italian, read all about it here.
How does a bacterium become resistant to antibiotics? Years ago, it was common to hear experts claim that the overuse of antibiotics is to blame; it has been said that it is due to a kind of natural selection i.e. the use of antibiotics ensures that only the toughest bacteria survive. Then, these macho bacteria replicate and give rise to many more hardy bacteria which eventually usurp the weaker strains and an increase in resistance takes place. Although this explanation sounds plausible, it is not accurate. The truth is that sex has a lot to do with it. Just like you and I, bacteria like to have sex; birds do it, bees do it, so why not bacteria (bacterium does not live on bread alone)? Sex allows bacteria to acquire new characteristics by exchanging genes (biologically speaking, this exchange of genes is the original reason for having sex). Eventually a mutant gene will be exchanged which confers resistance to certain antibiotics; individuals with this gene will be more successful and will multiply. It has nothing to do with the overuse of antibiotics.
According to New Scientist, tuberculosis was responsible for 1 in 5 deaths in Europe from the 1600s to the 1900s, and now it's back with a vengeance. This strain of TB is difficult to diagnose and if resistant patients are not identified quickly, they can become biological time-bombs that can easily infect anybody they come in contact with. Will it wreak the same havoc as the "white plague" or will human ingenuity prevail? Humanity may win this battle, but what other plagues threaten us? New strains of bacteria and even brand new bacteria may crop up at any time and with little warning so we must be vigilant ... just like we need to be vigilant of the evil that is latent in all of humanity.
Thoughts about science, human nature and other stuff.
