Does the current influenza activity generate stock market responses?

Abstract: This paper investigates if the release of influenza activity information during influenza seasons on the US aggregate level, from 1997 to 2015, generates any stock market responses. The hypothesis is that certain companies (i.e. heath insurance companies/pharmacies) might disadvantage/advantage from an unexpected mild/severe influenza season. We have tested the hypothesis by conducting event studies on historical dates when the seasonal influenza hit the US, but find no indication of influenza activity generating any stock market responses. The null hypothesis cannot be rejected on most seasons and the CAARs frequently trend in the wrong direction. Perhaps focusing on a state wise level and examining the accounting reports following an influenza season, will shed more light on where the missing costs/revenues are located. If not, perhaps the cost/revenues are too small and/or too uncertain to generate any significant stock market responses. In the end, the aim with this paper is to illuminate a previously unexplored topic in the financial markets, with the hope of leaving the door a bit more open than it was before, and thereby encouraging further research on the topic.