Decline in influenza-associated mortality among Dutch elderly following the introduction of a nationwide vaccination program

Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, The Netherlands.
Vaccine (Impact Factor: 3.62). 09/2008; 26(44):5567-74. DOI: 10.1016/j.vaccine.2008.08.003
Source: PubMed


With a retrospective nationwide cohort study in the Netherlands over 1992-2003, using mortality and viral surveillance data, the aim was to assess by means of rate difference methods the influenza-associated mortality in the elderly before and after the introduction of a nationwide influenza vaccination program in 1996 (vaccination coverage raised from below 50 to 80%). The average annual influenza-associated mortality declined in the years before and after the introduction from 131 to 105 per 100,000 persons (relative risk 0.80). The decline was largest in the age group 65-69 years (relative risk 0.54) and less in those aged 75 years and older. Validation by Serfling-type regression analysis revealed similar results. In conclusion, routine influenza vaccination among Dutch elderly was associated with a significant decrease in influenza-associated mortality, notably in those aged 65-69 years.

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