There is little doubt that the term Pandemic has come to dominate our lives. Over the last few months, the term Pandemic has been on everyone's lips. But what exactly is a Pandemic?
The term comes from the Greek pan meaning all and demos meaning the people. So, in theory a Pandemic should be a disease that affects all the people. But the term remains imprecise, particularly when we must rely on the WHO recognising such an event.
The WHO usually declare a disease outbreak a Pandemic when they believe it is in the process of spreading around the world, is virulent, and about to infect a large proportion of all of us. Yet it is impossible to find an outbreak of infectious disease that affected all the world or all the people in any country.
Many people and some countries have been able to avoid even the deadliest infections because of their geographic location, social isolation, degree of immunity or just good fortune. There is little doubt that declaring a disease outbreak as a pandemic encourages Governments and people to adopt avoidance measures but it also produces a wave of human response characterised by fear, hysteria and panic which often overwhelms the number of cases and deaths.
Historically most Pandemics have been of relatively short duration rarely lasting more than six months and usually coming in an explosive set of waves, following a slow onset. The 1919 Flu Pandemic in Australia demonstrates this only too well following what became known as the epidemic curve, with a slow onset rising to a peak and then declining only to reappear some weeks later in a virulent second wave.
But we tend to think of all pandemics this way when there is also a major disease outbreak called a Slow Pandemic where cases and deaths can continue over years or decades. Australia's Polio Pandemic is a good example where the disease affected the country for more than 50 years. HIV/AIDS is another example.
Australia is no stranger to pandemics or for that matter major epidemics. Since 1789 Australia has been swept up in at least 20 Pandemics and more than 36 major epidemics. Many of these were major events in Australian history causing many deaths and creating an extraordinary environment of fear and terror.
Some remain almost totally forgotten to this day such as the pandemic of Encephalitis Lethargica which swept through Australia causing thousands of cases in the 1920s and producing incredible scenes of fear and hysteria. And what about the outbreak of smallpox that affected much of New South Wales between 1913 and 1917 or the dengue epidemic of 1925-26 when more than 550,000 people in Eastern Australia caught the disease. Our ability to forget our past, and learn from it, continues to dominate modern life.
But what have been the worst Pandemics that Australia has suffered through? Well it depends on whether you simply consider cases and deaths or whether human reaction, fear and panic are also important. In the first case there would seem to be at least 9 or 10 major Pandemic outbreaks in Australia that caused tens of thousands of cases and deaths. The 1919 Flu Pandemic stands out causing at least 1.8 million cases and more than 15,000 deaths. But what about the disease outbreak that killed thousands of Aboriginals in 1789. Whether it was smallpox or chickenpox remains disputable, but its impact was severe.
But there are many more Pandemic disasters such as the Scarlet Fever outbreak in 1875-76 which produced more than 20,000 cases and 5,000 deaths, mainly young children, or the Flu Pandemic of 1890-91 which quite possibly caused at least 800,000 cases and 3,000 deaths.
And then in the 20th Century we suffered through a Bubonic Plague outbreak that lingered for more than 10 years and Polio which devastated our country from 1903 until 1956. More recently HIV/AIDS, SARS, Swine Fever and now Coronavirus join the list.
In the second case there were pandemics which while they did not cause great numbers of cases and deaths produced great outpourings of human reaction particularly marked by fear, hysteria and panic. Plague and Smallpox probably head the list followed by Dengue, Polio and now Coronavirus.
Although the direct effects of Pandemics are often substantial the indirect costs are often much more insidious and widespread and can have wide-ranging effects. The indirect costs largely relate to people's psycho-social reactions and their perception of the risk of catching the infection. Coronavirus demonstrates this well where an infection is said to be highly contagious and spread by direct contact produces substantial human reaction particularly in the area of social distancing, avoidance, stockpiling of food and household essentials as well as avoiding or denied access to travel, retail and leisure activities.
Many of the Pandemics that Australia has lived through have caused great outpourings of fear, hysteria and panic. Plague Fear may indeed be one of our most basic fears deeply entrenched in our psyche and representing a mix of rational and irrational fears about contagion, infection, outsiders, risk and exposure. Most of us also preserve a certain scepticism about whether our Government and Health Experts can protect us during such crises.
Today, hardly a month seems to go by with the emergence of a new microbiological threat to our health and wellbeing. There is little doubt that we have not won the battle against infectious disease and over the next few decades will be faced by a resurgence of epidemics and Pandemics such as coronavirus. It is a disturbing thought.