NEWS: Plants may be spreading superbugs to humans.
SOURCE: The Hindu.
A superbug is usually defined as a microorganism that’s resistant to commonly used antibiotics – but not all superbugs are created equal.
The number of different antibiotics to which it can be resistant determines the degree of the superbug. Some are resistant to one or two, but others can be resistant to multiple drugs.
There are two major classes of bacteria, known as Gram positive and Gram negative. They take their names from how they respond to the Gram staining test, which in turn was named after Danish scientist Hans Christian Gram, who developed the technique.
A bacterium is known to be Gram negative or Gram positive based on its reaction to the test – Gram positive bacteria stain purple, and Gram negative do not.
Gram negative bacteria are generally considered the more difficult to treat. They include such nasties as E. coli, Salmonella, Pseudomonas, and the Gonococcus bacteria – responsible for the sexually transmitted infection gonorrhoea.
Antibiotics have a tough time dealing with Gram negative bacteria because of their additional outer membrane, which prevents drugs from getting inside. And if the drugs do manage to get in there, the bacteria have a pumping mechanism that forces them back out again so quickly, they don’t have time to work.
Gram negative bacterial infections concern doctors and researchers because there are fewer drugs to treat them and – more worryingly – fewer in the pipeline to deal with them in the future.
But that’s not to say that Gram positive infections aren’t of serious concern, too.
While they are easier to treat, and there are many more drugs available to combat them, there are also many, many times the numbers of drug-resistant infections from Gram positive bacteria compared with Gram negative.