Influenza-epidemie in een verpleeghuis door een virus dat niet in het vaccin was opgenomen

- In the autumn of 1992 two-thirds of the population of a nursing home in Amsterdam was vaccinated against influenza. However, in March 1993 an outbreak of an influenza like illnesses occurred with a morbidity rate of 49 and a mortality rate of 10. There was sufficient serological evidence to show that the vaccine as such had induced adequate immunity. As the causative agent an influenza AH3N2 virus was identified. The failing activity of the vaccine in this instance was apparently caused by the absence of sufficient antigen similarity between the AH3N2 vaccine component and the epidemic virus (‘vaccine mismatch’).