Mitigation and delaying (or ‘containment’)strategies as the new influenza A(H1N1) virus comes into Europe

Currently, as epidemics of the new influenza A(H1N1) virus are extending globally, some European countries are considering how robustly to undertake case-finding among the first cases and whether to pursue and treat contacts. A strategy to vigorously trace all of those entering or appearing and to treat both them and their contacts is known as ‘delaying’ (or even ‘containment’), whereas a strategy to lessen the effect of the disease in many possible ways is known as ‘mitigation’. Many of the tools and messages used are actually the same for both. However, the crucial difference is that, in delaying, they are used more widely and vigorously as attempts are made to identify all or most infected people and people at risk through contact tracing. This guidance paper describes the background and presents the evidence, experience and practical considerations to assist EU/EEA countries in making policy decisions on this topic. It is noted that for both strategies it is important to have good messages for citizens travelling to and from Europe, with special attention to how those coming to or returning to European countries from affected areas would consider what to do should they fall sick following arrival.