Eurosurveillance - Volume 15, Issue 31, 05 August 2010

The prevalence of antibodies reactive to the 2009 pandemic influenza A(H1N1) was determined in sera collected before the start of the pandemic, during the early phase, and after the main epidemic wave and nationwide vaccination campaign in Norway. A substantial rise in prevalence of antibodies at protective titres, from 3.2% to 44.9%, was observed between August 2009 and January 2010. The highest prevalence, 65.3%, was seen in the age group of 10-19 year-olds.

We report on a case of toxigenic Corynebacterium ulcerans infection in a fully immunised veterinary student, investigated in London, United Kingdom, in May 2010. There was no ongoing transmission in human contacts. Possible animal sources were identified.

Data collected over winter 2009 by five World Health Organisation National Influenza Centres in the southern hemisphere were used to examine the circulation of pandemic and seasonal influenza A strains during the first pandemic wave in the southern hemisphere. There is compelling evidence that the pandemic influenza A(H1N1) 2009 virus significantly displaced seasonal influenza A(H1N1) and, to a lesser extent, A(H3N2) viruses circulating in the southern hemisphere. Complete replacement of seasonal influenza A strains, however, was not observed during the first pandemic wave.

The use of routinely available electronic sources of healthcare data on the spread of influenza has the potential to enhance current surveillance activities. This study aimed to develop a method for identifying influenza-related records from general practitioner (GP) out-of-hours (OOH) services in Ireland. Data from one such service were interrogated for keywords relating to influenza-like illness (ILI) and a proxy measure of influenza activity in the community setting was developed. Comparison of this syndromic surveillance measure with national data on ILI consultation rates demonstrated a statistically significant temporal correlation. In five out of six influenza seasons investigated, peaks in the GP OOH influenza-related calls appeared at least one week ahead of peaks in the national ILI consultation rates. The method described in this paper has been extended to nine OOH services in Ireland (covering 70% of the Irish population) to provide weekly figures on self-reported illness for influenza in the community and its data have been incorporated into the national weekly influenza reports produced by the Health Protection Surveillance Centre. These data should provide early warnings of both seasonal and pandemic influenza in Ireland.