Pandemics appear to have occurred throughout history, the first being recognized in 1580. Reviewing previous pandemics can give an indication of what might be expected, however nothing is certain – it is impossible to predict the next pandemic virus or its impact, as demonstrated by the 2009 A(H1N1) pandemic.
By guest bloggers Jonathan Van-Tam and Chloe Sellwood
The 2009 flu pandemic was officially declared on 11 June 2009. The first cases of A(H1N1)pdm09 occurred in Mexico between January and March 2009, followed shortly by early first waves in north America, the UK and across the southern hemisphere countries in spring 2009. Many of the first cases of influenza A(H1N1)pdm09 in Europe were reported in travellers returning from Mexico or the USA within a few days of the outbreak being announced, and cases rapidly emerged in countries as far away as New Zealand. A second, more widespread northern hemisphere wave followed in autumn/winter of the same year. After the pandemic was declared over on 10 August 2010 there were effective ‘third waves’ of A(H1N1)pdm09 disease in both southern then northern hemispheres in the following winter seasons.
In the UK, the treatment phase saw the establishment of services to offer treatment antivirals to patients who met pre-defined symptomatic clinical criteria. The National Pandemic Flu Service (NPFS) was activated in England on 23 July 2009 to provide an online and telephone self‐assessment service and local Antiviral Collection Points (ACPs). By the time of its closure on 11 February 2010, NPFS had supplied antiviral drugs to 1.2 million people.
Data from the 2009 pandemic are still being analysed, but the advantages of early versus late initiation of therapy are already clear. The 2009 experience has demonstrated that neuraminidase inhibitors (NAIs) can be used safely in a widespread fashion, and that they may be the only specific pharmaceutical intervention available for up to 6 months until vaccines are manufactured. Although virus resistance to NAIs did not become widespread in 2009-10, this future possibility cannot be eliminated for a future pandemic virus. Thus, a mixed stockpile of NAIs is recommended, including an intravenous formulation for patients with severe disease.
The 2009 pandemic was the first influenza pandemic of the internet age. Websites and social messaging services such as Twitter® and Facebook® provided a quick and efficient way to provide up-to-date information for the public, but the internet also enables rumours and misinformation to transmit rapidly from anywhere in the world. Health authorities therefore need to know how to respond to this challenge.
Areas of pandemic planning specifically identifiable as in need of improvement in the post-pandemic period include increased flexibility and adaptability of response at national level, planning for intensive care provision and communication with the public and healthcare workers. Although revealing problems and issues, national and international evaluations of the response to the 2009 pandemic suggest that overall the intensive pandemic planning undertaken since 2004 proved worthwhile.