Heroes Not Zombies

The treatment of infectious diseases is often presented as one of the great success stories of modern medicine. There’s no doubt that antibiotics have the potential to kill many bacteria in life threatening situations and so have saved many lives. Antivirals don’t have as good a success rate as antibiotics (despite the strange current craze for dishing out Tamiflu). However, the story of infectious disease is not so simple. I came across a feature about this on the BBC site the other day, headed “Are we losing the war on bugs?” This is typical language about the issue of infection – it is presented as a war, which is about as helpful a metaphor as the “war on drugs” or the “war on terror”. If these are wars, then when could we reasonably expect them to be over? In fact, the BBC article is the most heavily war metaphor laden article on infectious disease I’ve read for a long time.

And indeed our battle to outwit the bacteria which have caused death and decimation down the centuries has revealed just what a formidable foe they can be.
It is a war of attrition. There have been points where we have been advancing, and points when we have had to beat a retreat.
In part is the ability to keep people alive for longer which has enabled some bugs to find a chink in our armour
Influenza is seen as the most wily of viruses, constantly adapting to thwart our attempts to combat it.
We will always be at war with microbes. Their genetic promiscuity is impressive, but we are learning more about them all the time. They are versatile and enduring – but so are we

Many of those phrases are direct quotes from scientists working in this area, so it isn’t only the journalist who has bought into this metaphor. Is this a helpful way to think about infection? I don’t think so. The clue lies in that last quote about microbes being “versatile and enduring” and the admission that it isn’t the kind of war which can be won.

Bacteria and viruses are part Nature, just as we are. We have a complex relationship with them. We couldn’t live without them and sometimes we can’t live with them. So what exactly is the situation? Having invented antibiotics have we discovered how to control infectious disease? Because that’s what the war metaphor is all about. It’s that dominant scientism belief that Man can conquer and control Nature. Scientifically, and philosophically, I think that’s a foolish stance.

I recently came across a research article from 2000, written by Mitchell Cohen, and published in Nature Insight (Volume 406(6797), 17 August 2000, pp 762-76). The article is entitled “Changing patterns of infectious disease” (no war metaphor, unlike the BBC piece)
Here’s the abstract

Despite a century of often successful prevention and control efforts, infectious diseases remain an important global problem in public health, causing over 13 million deaths each year. Changes in society, technology and the microorganisms themselves are contributing to the emergence of new diseases, the re-emergence of diseases once controlled, and to the development of antimicrobial resistance. Two areas of special concern in the twenty-first century are food-borne disease and antimicrobial resistance. The effective control of infectious diseases in the new millennium will require effective public health infrastructures that will rapidly recognize and respond to them and will prevent emerging problems

The author points out that at the beginning of the 20th century infectious diseases were the leading causes of death worldwide, and that average life expectancy was only 47 largely due to the number of children who died in infancy from infections. However, he then goes on to point out that from 1700 to 1900 life expectancy had risen in Britain from 17 to 52 and that the death rate from TB had fallen by 80%. Antibiotics hadn’t been invented yet.
The reasons for the change were “primarily decreases in host susceptibility and/or disease transmission.” After the invention of antibiotics infectious disease became even less of a cause of death “Between 1900 and 1980, mortality from infectious disease fell from 797 to 36 per 100,000” “By the end of the twentieth century, in most of the developed world, mortality from infectious diseases had been replaced by mortality from chronic illnesses such as heart disease, cancer and stroke” (war on chronic disease anyone?)
However, it’s a more complex picture, with new infections, and old infections now resistant to previously effective treatments. 13 million people died from infections in 1998, and the death rates from infectious disease have risen even in developed countries. Why? The conclusion reached by this particular author is interesting “The recurring theme throughout all of these factors that influence the emergence of infectious diseases is change”. What changes? Well, too many to cover here actually, but not least changes in demographics with increasing numbers of vulnerable people, from the elderly to the malnourished; changing patterns of human behaviour with more children being cared for in groups in nurseries, and more international travel; changes in the amount of ready-prepared foods being eaten placing food safety out of the hands of individuals and into industry and commerce; and the over-prescribing of antimicrobial drugs rises in resistance.

So the war metaphor doesn’t really work. The problem turns out to be more complex than beating the baddies. The best explanations for disease patterns emerge from understandings of how we live in this world. Yes, we do need drugs to treat life threatening infectious disease but the biggest advances will come from attending to our adaptability and our resilience. As a species we need to learn what influences these characteristics and to take measures to increase them. So here’s your challenge. What do you think can increase adaptability and resilience? At a personal level, and at a global level?