London School of Hygiene & Tropical Medicine

A new collaborative study conducted by a team of researchers led by Professor Richard Smith at the School (LSHTM), Professor Tony Barnett of the London School of Economics and Political Science (LSE) and Professor Joyce Tait of the University of Edinburgh, has examined what effect public response to a flu pandemic would have on the UK's economy.

The report, published in the British Medical Journal (BMJ) on Friday 20th November, studied several potential responses to a pandemic, such as school closures and a wide vaccination programme. The authors concluded that, whilst the disease itself would have an impact, fear-induced school closures and absences from work were likely to be far more detrimental to the UK economy. They also advised that having sufficient stocks of vaccine would help substantially reduce the economic cost of a pandemic.

The team replicated various disease scenarios, vaccination programmes, school closures, and "prophylactic absenteeism," where healthy people avoid social contact, including going to work, using economic data from 2004. The results showed that pandemic influenza itself, even if it caused high fatalities, would only reduce Gross Domestic Product by less than 4.5% (around £70bn).

However, this impact could be exacerbated by other factors. The fragile state of the UK economy could be further strained by a pandemic in the near future, exaggerating the effect of recession and slowing economic recovery. In addition, school closures and prophylactic absenteeism, whether imposed by government or as a result of the fear of infection, could greatly increase the economic impact of a pandemic, while providing questionable health gains. The authors advised that these policies be avoided except in exceptional circumstances. They also suggest that the cost of vaccinations is likely to be lower than the economic savings gained from vaccination, even in the mildest of pandemics. In the event of a high or extreme fatality pandemic, a matched vaccine might be the only method to avoid the unprecedented economic effects of behavioural change.

Professor Smith says, "We learned several lessons from the way the potential panic over SARS was handled in 2003. It seems that people tend to worry about a disease only if they personally know someone who has been affected by it and if it appears to have a high fatality rate. It seems that people tend to have around 300 people in their social network - friends, family, neighbours, colleagues, etc - and so we worked on the basis that behaviour is likely to change substantially once someone within this network becomes infected and especially if they die.

"Even though the news or the Department of Health will be offering advice and opinion on whether people should worry and how they should react, evidence seems to suggest that, once people are aware of close friends who have been infected, they will begin to change their behaviour. This is important as it affects social interaction, staying home from work, shopping online instead of in person, school closures and it is this - not the disease itself - that drives the overall impact on the economy, which of course it can least sustain as we come out of recession.

Professor Tony Barnett adds, "lessons can be learned from this by policy makers, who have to decide on vaccination programmes and the decisions on whether or not to close schools or encourage people to have less social interaction. Clearly, the broader implications for the economy mean that it is important to advise 'business as usual' and to ensure that vaccination programmes are implemented early enough to prevent 'social network' effect."