Medical science has brought about two seriously adverse effects in the modern world. Firstly, in the last 250 years it caused the world population to burst forth from a fairly stable population of about 1 billion. The constraints limiting us to that size were accidents, disease and the final running out of niches where food could be comfortably grown with manual labour.
Today, after the industrial revolution, world population is now over 7 billion — more of us being insufficiently nourished than not — with a pretty sure guarantee that we’ll reach 11 or 12 billion before topping out.
In the advanced countries in the last 20 to 30 years there is growing evidence that health costs for most of their populations are growing too high to be affordable. What with the steady decline in real earnings for most — allowing for inflation — then insurance schemes, whether state or private will not be affordable before too long. Ironically, this is at a time when popular demands for more sophisticated methods of health care are rising remorselessly.
What makes both dilemmas even sharper is that on the bacterial disease side, because of acquired genetic immunity, we have almost run out of antibiotics that will work. On the virological disease side, the increasing use of vaccination means that human immune systems are weaker. In the increasingly empty ecological niches in our DNA we will be increasingly unable to cope with newly mutating killer diseases.
Also, because we are increasingly living at high density in cities where both sorts of disease can spread all the more rapidly it is not surprising that epidemiologists are telling us that diseases of high mortality will be inevitable. In the years to come we are probably going to have to re-jig many of the assumptions we have made about the benefits we have gained from the industrial revolution.