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Abstract Background In temperate zones, all-cause mortality exhibits a marked seasonality, and one of the main causes of winter excess mortality is influenza. There is a tradition of using statistical models based on mortality from respiratory illnesses (Pneumonia and Influenza: PI) or all-cause mortality for estimating the number of deaths related to influenza. Different authors have applied different estimation methodologies. We estimated mortality related to influenza and periods with extreme temperatures in Denmark over the seasons 1994/95 to 2009/10. Methods We applied a multivariable time-series model with all-cause mortality as outcome, activity of influenza-like illness (ILI) and excess temperatures as explanatory variables, controlling for trend, season, age, and gender. Two estimates of excess mortality related to influenza were obtained: (1) ILI-attributable mortality modelled directly on ILI-activity, and (2) influenza-associated mortality based on an influenza-index, designed to mimic the influenza transmission. Results The median ILI-attributable mortality per 100,000 population was 35 (range 6 to 100) per season which corresponds to findings from comparable countries. Overall, 88% of these deaths occurred among persons ≥ 65 years of age. The median influenza-associated mortality per 100,000 population was 26 (range 0 to 73), slightly higher than estimates based on pneumonia and influenza cause-specific mortality as estimated from other countries. Further, there was a tendency of declining mortality over the years. The influenza A(H3N2) seasons of 1995/96 and 1998/99 stood out with a high mortality, whereas the A(H3N2) 2005/6 season and the 2009 A(H1N1) influenza pandemic had none or only modest impact on mortality. Variations in mortality were also related to extreme temperatures: cold winters periods and hot summers periods were associated with excess mortality. Conclusion It is doable to model influenza-related mortality based on data on all-cause mortality and ILI, data that are easily obtainable in many countries and less subject to bias and subjective interpretation than cause-of-death data. Further work is needed to understand the variations in mortality observed across seasons and in particular the impact of vaccination against influenza.

Climate changes will likely have an impact on the spectrum of infectious diseases in Europe. We may see an increase in vector-borne diseases, diseases spread by rodents such as Hantavirus, and food- and water-borne diseases. As the effects of climate changes are likely to occur gradually, a modern industrialised country such as Denmark will have the opportunity to adapt to the expected changes.

Introduction: With the introduction of MMR vaccination in the childhood vaccination programme in 1987, measles in Denmark is now rare. However, sub-optimal vaccination coverage results in the accumulation of susceptibles and outbreaks may still occur., Material and Methods: Information from epidemiological investigations and experience gained from the management of measles cases in a children's ward in Aalborg Hospital are described., Results: A nine-year-old child was admitted with a tentative diagnosis of travel associated clinical malaria. The patient was not isolated and information on possible exposure to measles was only obtained upon discharge. Laboratory confirmation was received ten days after admission. At this time, a previous close-contact patient was re-admitted with high grade fever. This second patient was isolated following laboratory confirmation, and other hospitalised children received passive immunization. A total of 24 cases were reported, of which 12 patients were infected whilst hospitalisation and 21 were unvaccinated against measles., Discussion: In a sub-optimally immunized population the introduction of measles virus may cause an outbreak in a local setting including a hospital environment, with potential spread to other geographical areas and hospitals. Obtaining a history of possible exposure to childhood infections, irrespective of the vaccination status, becomes highly significant upon admission. In the case of measles a detailed travel history is essential.