Low adherence to influenza vaccination campaigns: is the H1N1 virus pandemic to be blamed?

Background: Over the last few months, debates about the handling of the influenza virus A (H1N1) pandemic took place, in particular regarding the change of the WHO pandemic definition, economic interests, the dramatic communication style of mass media. The activation of plans to reduce the virus diffusion resulted in an important investment of resources. Were those investments proportionate to the risk? Was the pandemic overrated? The workload of the Pediatric Emergency Room (P.E.R.) at a teaching hospital in Varese (Northern Italy) was investigated in order to evaluate the local diffusion and severity of the new H1N1 influenza epidemic.

Discussion: A 100% increase of the number of P.E.R. visits, particularly for influenza-like illness, was recorded during weeks 42-46 of 2009 (October, 17 to November, 2); the low rate of hospitalization and the mild presentation of the infection gave rise to the conclusion that the pandemic risk was overrated. Mass media communications concerning the new virus created a disproportionate fear in the population that significantly enhanced the burden of cares at the hospital. In the absence of generally implemented measures for etiological diagnosis, the actual incidence of the H1N1 infection could not be estimated. Virus identification, in fact, was limited to children showing severe symptoms after consultancy with an infectious disease specialist. The alarming nature of the communication campaign and the choice to limit etiologic diagnosis to severe cases created a climate of uncertainty which significantly contributed to the massive admissions to the P.E.R..

Summary: The communication strategy adopted by the mass media was an important element during the pandemic: the absence of clarity contributed to the spread of a pandemic phobia that appeared to result more from the sensationalism of the campaign than from infection with the novel influenza A variant of human, avian, swine origin virus. One relevant effect of the media coverage was the extremely low adherence rate to the vaccination campaign for the 2009-2010 and 2010-2011, especially among the high-risk population and health care workers. One positive consequence was, however, the spread of preventive hygiene measures, such as hand washing.