UNDER THE MICROSCOPEWe're not immune to a Spanish Flu-type pandemic - in fact, our complex society makes us more vulnerable, writes William Reville
I ARRIVED BACK from a short break recently to find the Government booklet Preparing for Major Emergencies in my accumulated post. Two of the emergencies itemised (nuclear emergencies and pandemic influenza) are possibly even more dangerous than described in this booklet because of the fragile nature of our complex civilisation. This fragility is well described by Debora MacKenzie in New Scientist (April 5th).
We tend to think that society is now so complex and clever that it is immune from collapse. But, on the contrary, the experts tell us that our very complexity makes us fragile and vulnerable. For example, a severe pandemic might cause crucial systems in our social organisation to collapse, with disastrous overall consequences.
Pandemic means a worldwide epidemic. It could be pandemic influenza, or something worse such as ebola or smallpox. The world has seen many pandemics. The Black Death killed one third of the population of Europe in 1348 and another plague had a similar effect on the population of the Roman empire in 170 AD. The Black Death did not threaten European civilisation, whereas the Roman plague initiated a spiral of effects ending in collapse. MacKenzie explains the difference in terms of complexity of social organisation.
Both the Roman and medieval societies were hierarchically organised, but in different ways. Fourteenth-century Europe was feudal, with peasant farmers comprising over 80 per cent of the population. Each death removed a food producer, but also a food consumer, so that there was little net effect. The Roman empire had huge urban populations that depended on peasant farmers for food, soldiers and taxes. The pandemic affected food production and upkeep of the army, which weakened the ability to repel invaders, which further killed peasants and weakened agriculture, and so on. The argument is that a severe pandemic could have a similar effect today.
The most recent severe pandemic was the influenza pandemic in 1918 which killed more people than the first World War. More people died in one year than died in the Black Death Bubonic Plague (1347-1351). Known as the "Spanish Flu", it killed between 20 and 40 million people. It was most deadly for people aged 20 to 40, and it infected almost 30 per cent of all Americans, depressing the average US lifespan by 10 years. The influenza is thought to have originated in China in a rare genetic modification of the influenza virus. The influenza circled the globe, speeding along trade routes and assisted by the mass movement of armies. In India there were 50 deaths per 1,000 people.
Civilisation has developed from a hierarchical organisation into a complex, highly interconnected network. Such networks, McKenzie explains, are vulnerable to perturbations and in many ways are less resilient than the old hierarchies. The networks contain "hubs", for example, people whose actions link all the rest. Truck drivers are quoted as an example: MacKenzie recounts a 10-day strike in the UK in 2000 which blocked petrol deliveries from oil refineries. One-third of the country's motorists ran out of petrol, shops began to run out of food, hospitals were reduced to minimal services, some train/buses services were cancelled, waste accumulated and bodies remained unburied. A subsequent study predicted huge economic loss and quick deterioration in living standards if all road haulage in the UK shut down for one week. A severe influenza pandemic could easily cripple road haulage with most drivers out sick. Hospitals also work on a "just in time" delivery system and keep only a two-day supply of oxygen; just as critical is chlorine for water purification plants. If key workers fail to turn up in the energy, transport, food, water and telecommunications sectors, this could trigger a major crisis.
Why would even small disruption of road haulage cause such severe effects? MacKenzie cites "just in time" delivery as one reason. Shops and businesses no longer keep large stocks because this is expensive, so they rely on frequent small deliveries. Cities on average have only three days' stocks of food. Emergency advice in the US typically calls on people to keep three weeks' supply of food and water stockpiled to be used in the event of a pandemic. Some experts call for a 10-week supply to be stockpiled. In contrast, our Irish Emergency Planning booklet calls only for a one--week stockpile.
It is estimated that a new pandemic equal to the Spanish Flu would cause about 25 per cent staff absences from work. In that event it would be just about possible to maintain the supply of services critical to society. However, if absences from work rose to 50 per cent, which could result from a more severe pandemic, that would be an entirely different story.
William Reville is associate professor of biochemistry and public awareness of Science Officer at UCC. http://understandingscience.ucc.ie.