Whenever disease-causing bacteria encounter a new obstacle, they have a way to overcome it by exchanging DNA with their relatives in order to adapt to a new environments and conditions.  This revelations by scientists from NIAID seem to settle the long-standing question of the origin, the how and why of two diseases.  Toxic Shock Syndrome (TSS) and anti-biotic-resistant infections.
Whether the isolated strains pick up new genes once and then spread through the population or did they acquire the genes on many occasions seem to follow the latter as the correct explanation   according to the research study by Dr. James Musser.  He further raises a concern that harmless bacteria can even become dangerous such as S. aureus, which people may unknowingly harbor on their skins, nose and throat even without any sign of illness.  However, whether any particular S. aureus strains can cause disease depends on its genes, because many other strains can survive in different environments.  To learn how genes are exchanged between strains, study team used 36 different strains of S. aureus to determine which genes help each strain to survive by using a technique called DNA micro array analysis.  They discovered by screening their samples that a fourth of the genomes are not required on the bacteria’s basic life processes and therefore dispensable.  These genes provide flexibility in the bacterium’s ability to cause disease in humans, in animals and other organisms.
A case in point is the outbreak of TSS in 1970.  Because of the use of hyper absorbable tampoons by menstruating women had an environment change for the host.  The research suggests that repeated exposure to antibiotics causes the bacteria to adapt to changes by picking up genes and enables it to spread through the population.
These findings opened a new way of approach and strategy to address the problem. Read more