Microorganisms have been causing infections in humans for millennia.  In the pre antibiotic era, humans relied on host defences to fight these infections. Needless to say many perished.  With the advent of antibiotics, humans fought back.  However, over the decades, the organisms have increasingly become resistant to these antibiotics.  As far as antibiotic resistance is concerned, there is a real war of attrition going on.

In favour of the microorganisms are the following:-

1. According to Darwin’s laws of evolution by natural selection, their evolution time scale is extremely short. They can easily acquire resistance, multiply and spread unseen among humans and other animals. In comparison, human evolution time scale is very long in that it takes a long time to change their characteristics.
2. Because of the major advances in medicine, many people with weakened host defences survive. Consequently, low virulence organisms which are usually highly resistant to antibiotics infect this group of people. This also creates the opportunity for these organisms to pass on their resistance to other resident organisms.
3. The big brains of humans allow them to perform numerous activities that unwittingly favour the spread of resistant organisms for example ease of travel.

In favour of humans are the following:-

1. The large human brain can make new antibiotics and vaccines with the latter boosting the host defences. It can also enable humans to perform other activities like using antibiotics rationally and taking infection control precautions to prevent the spread of resistant organisms.
2. The majority of humans have intact host defences to fight infections.

My prediction is that the war of attrition will go on for a long time. Check out my other views on infections in THE BUGS DOCTOR WITH A PASSION FOR MUSIC