Costing infectious disease outbreaks for economic evaluation: a review for hepatitis A.

With the aim to understand and estimate the economic impact of outbreaks of community-acquired infections, we performed a review focusing on hepatitis A outbreaks, and retained 13 papers that had collected relevant cost information during such outbreaks. All costs in this article are expressed in USD, year 2007 values. The costs of hepatitis A outbreaks ranged from USD140 000 to US36 million, and the costs per case in an outbreak situation ranged from USD3824 to USD200 480. These costs were typically found to be substantially higher than estimates from cost-of-illness studies (i.e. costs for sporadic cases) and estimates used in cost-effectiveness analyses, mostly because of costly outbreak-control measures. Post-exposure prophylaxis is a major cost factor, especially for food-borne outbreaks. As a result of the increasing proportion of those susceptible to hepatitis A in low-incidence countries, future outbreaks could, on average, increase in size. The increasing occurrence of hepatitis A cases in outbreak situations and the associated control costs should appropriately be accounted for in economic evaluations of vaccination programmes in low-incidence countries. In order to do this, more studies documenting such outbreak-control strategies in terms of costs and resource use are needed.