Real or media-mediated outbreak of coxsackie infections in 2002 in Greece?

The purpose of this study was to provide evidence about the existence of a coxsackie B outbreak in Greece in 2002 by comparing data of laboratory confirmed coxsackie B recent infections in northern Greece between 1998-2001 with data from 2002. The infections were confirmed serologically, using the indirect immunofluorescence method detecting IgM antibodies for coxsackie B1-B6 viruses. Sera from 2701 patients residents of northern Greece who were suspected to be suffering from coxsackie B virus infections were examined: 2056 between 1998 and 2001, and 645 in 2002. The comparison between the results of laboratory confirmed cases and data available at the laboratory between the two periods showed that: - The total number of patients examined per year was higher in 2002 (645 versus an annual average of 514 in 1998-2001). - The proportion of laboratory confirmed recent infections was lower in 2002 (27.8% versus 32.7%) and the estimated incidence was 0.66/10 000 for 2002 and 0.32-0.84/10 000 for 1998-2001. - The age distribution differed: the proportions of cases in children versus cases in adults were reversed in 2002 compared with 1998-2001, with a higher proportion among children in 2002. The difference between the two periods was statistically significant. Children aged 3-5 years were the age group most affected in 2002. - Seasonal distribution remained the same for both periods (peaks in spring and autumn). In 2002, three fatal cases occurred in April, but no deaths were reported in 1998-2001. - The clinical syndromes involved also differed: cases of respiratory infections, mainly pneumonia, rose from 5.75% to 24.3% in children in 2002 and cases of myopericarditis rose in adults from 13% in 1998-2001 to 29.5% in 2002. The last finding, combined with the involvement of the media (because of the three fatal cases) and the panic in the general public that followed suggested that an outbreak had occurred, but we conclude that there was no outbreak.