title: [Influenza season 1999/2000 and vaccine composition for the season 2000/01].
abstract: The first signs of influenza activity in the Netherlands during the 1999/2000 influenza season were the isolation of an influenza A (H3N2) virus in week 40 and of two more in week 43 of 1999. From week 50 onwards, a strong increase of the clinical influenza activity was observed which reached its peak in weeks 1 and 2 of 2000 and then rapidly declined. The clinical influenza activity was associated with the isolation of predominantly influenza A (H3N2) viruses. Near the end of the epidemic, influenza A (H1N1) and influenza B viruses were isolated sporadically. The antigenic properties of the influenza A (H3N2) viruses resembled those of the epidemic strains isolated in the previous season and the vaccine strain A/Sydney/5/97. This influenza season, influenza B viruses did not play a significant role and they matched the vaccine strain B/Yamanashi/166/98. In addition, a small number of influenza A (H1N1) viruses were isolated. Some of these viruses resembled the old variant of influenza A (H1N1) viruses, A/Bayern/7/95, whilst others showed a close antigenic relationship with the vaccine strain recommended for the next influenza season, A/New Caledonia/20/99. For the influenza season 2000/'01, it is recommended by the World Health Organization that the vaccines contain the following (or similar) virus strains: A/Moscow/10/99 (H3N2), A/New Caledonia/20/99 (H1N1) and B/Beijing/184/93.
authors.affiliation: Nationaal Influenza Centrum van de Wereldgezondheidsorganisatie, Erasmus Universiteit, afd. Virologie, Rotterdam.
authors.forename: G F
authors.initials: GF
authors.lastname: Rimmelzwaan
authors.forename: J C
authors.initials: JC
authors.lastname: de Jong
authors.forename: A I
authors.initials: AI
authors.lastname: Bartelds
authors.forename: J W
authors.initials: JW
authors.lastname: Dorigo-Zetsma
authors.forename: R A
authors.initials: RA
authors.lastname: Fouchier
authors.forename: A D
authors.initials: AD
authors.lastname: Osterhaus
mesh_terms: D004196:Disease Outbreaks / Q000517:prevention & control*; D005544:Forecasting; D006801:Humans; D009980:Influenza A virus / Q000302:isolation & purification*; D009981:Influenza B virus / Q000302:isolation & purification*; D007252:Influenza Vaccines; D007251:Influenza, Human / Q000453:epidemiology / Q000517:prevention & control* / Q000821:virology*; D009426:Netherlands / Q000453:epidemiology; D011159:Population Surveillance
chemical_list: D007252:Influenza Vaccines