ABSTRACT
Since the earliest descriptions of influenza-like disease by Hippocrates, influenza has infected billions and killed millions of people across the globe. A highly contagious disease, it is usually limited to just a few days’ illness with a low fatality rate. However, in times of epidemic and pandemic it can become so prevalent, infecting the majority of the population, that these elevated rates give rise to massive surges in mortality as influenza strikes ‘like a flash flood’ (Stöhr 2005: 407). With pneumonia, influenza remains one of the ten leading causes of death in the United States of America (Crosby 1993: 807) and Australia (AIHW 2004: 45). These two respiratory infections are commonly tallied together and frequently interact – in 1918 it was the complications from pneumonia that killed so many, contributing to a death toll of tens of millions. In the UK the average annual influenza death toll is currently around 12,000, and in the first week of 1999 alone more than 3,000 Britons died of influenza (BBC 1999g) – an outbreak that forced one hospital to hire a refrigerated truck as a temporary mortuary (BBC 1999c) – and this was not officially regarded as an epidemic. The winter of 1989-90 saw an epidemic claim an estimated 29,000 British lives (Radford 1995). Even in non-epidemic years it can have a major impact; for example, in Britain an average of approximately three working days per patient are lost annually as a result of flu, and it may account for approximately 10 per cent of sickness absences (BBC 1999d). An average year in the USA sees approximately 36,000 flu deaths, with more than 200,000 hospitalised (CDC 2004) at a cost to the economy of US$71-167 billion (WHO 2003). The World Health Organisation (WHO) estimates that influenza causes ‘between three to five million cases of severe illness and between 250,000 and 500,000 deaths every year around the world’ (WHO 2003). But all this may pale against the possibility of a pandemic that many now regard as inevitable, if not imminent. Indeed, in early 2005 the British government apparently recognised that an influenza pandemic was a greater risk than terrorism, particularly in terms of the number of people directly affected and the potential to disrupt society (Hall and Sample 2005).
