[Influenza. Consequences for health and prevention]

Investigations from abroad and from Denmark show that epidemics of influenza are not only accompanied by considerable morbidity but also by considerable excess mortality and a sizable increase in the number of admissions to hospital. The increases in the number of deaths comprise 170-320 per million of the population per epidemic. The excess mortality occurs primarily among individuals with chronic pulmonary and circulatory disease and may be very great in nursing homes and similar institutions. Influenza vaccination will, in general, provide protection of approximately 70% and does not cause noteworthy side effects. Amantadine and rimantadine chemoprophylaxis, which is employed in some countries, provides protection of 80-90% from Influenza A. Recommendations are established for influenza vaccination and a series of situations are quoted where it would be advisable to supplement or replace vaccination with chemoprophylaxis. It is important to attempt to improve the vaccination rates, eg. by means of informative activity, improved planning of the vaccination programmes and public support to vaccination of high-risk groups.