The New York Times reports this week that a new mutation has emerged which makes bacteria resistant to all antibiotics. The mutation has been discovered in India and Pakistan and is reported to be found in patients from the UK and the US who travel to this region to receive medical treatment. The mutation labeled NDM-1 according to the article has microbiologists and physicians worried that this could be the mother of all mutations. However, it is too early to tell if this is the case. How does a mutation come about and why is this mutation of concern?
Bacterial cells reproduce via cell division. A single bacterial cell creates a carbon of itself in multiplicative fashion. If a bacteria has basic characteristics (whether it causes disease or not), it will pass on those characteristics to it’s carbon copy. Bacterial cells obtain additional characteristics, such as antibiotic resistance through the uptake of a plasmid. A plasmid is a smaller, circular form of DNA which can give bacterial cells a variety of new characteristics and codes for ways by which the new characteristics can be expressed. Antibacterial resistance can be coded in bacteria in ways such as giving the bacteria the ability to synthesize enzymes to affect the antibiotics action or the bacteria can create structures called porins which shuffle antibiotics out of the cell. Plasmids, like the DNA that is innately in the bacterial cell is constantly undergoing evolutionary change and new characteristics can be created.
In a previous post, I discussed factors which have increased the spread of disease globally. Travel across the globe is one of the major ways by which disease can be introduced into susceptible populations. Medical travel to obtain treatments for a variety of aliments has been ongoing for many years. In this day and age, more and more people have used medical travel in the wake of loss of insurance, being denied claims or lower cost for certain medical treatments. Travelers returning from the India/Pakistan region to their home countries potentially could harbor this resistant bacteria. Only then and with time will we know if this is the super resistant bacteria that we have been fearing it’s arrival.