Heterogeneity in influenza seasonality and vaccine effectiveness in Australia, Chile, New Zealand and South Africa: early estimates of the 2019 influenza season

Euro Surveill. 2019 Nov;24(45):1900645. doi: 10.2807/1560-7917.ES.2019.24.45.1900645.

Abstract

We compared 2019 influenza seasonality and vaccine effectiveness (VE) in four southern hemisphere countries: Australia, Chile, New Zealand and South Africa. Influenza seasons differed in timing, duration, intensity and predominant circulating viruses. VE estimates were also heterogeneous, with all-ages point estimates ranging from 7-70% (I2: 33%) for A(H1N1)pdm09, 4-57% (I2: 49%) for A(H3N2) and 29-66% (I2: 0%) for B. Caution should be applied when attempting to use southern hemisphere data to predict the northern hemisphere influenza season.

Keywords: influenza; influenza vaccines; sentinel surveillance; southern hemisphere; vaccine effectiveness.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Australia / epidemiology
  • Child
  • Chile / epidemiology
  • Female
  • Humans
  • Influenza A Virus, H1N1 Subtype / genetics*
  • Influenza A Virus, H1N1 Subtype / immunology
  • Influenza A Virus, H1N1 Subtype / isolation & purification
  • Influenza A Virus, H3N2 Subtype / genetics*
  • Influenza A Virus, H3N2 Subtype / immunology
  • Influenza A Virus, H3N2 Subtype / isolation & purification
  • Influenza B virus / genetics*
  • Influenza B virus / immunology
  • Influenza B virus / isolation & purification
  • Influenza Vaccines / administration & dosage
  • Influenza Vaccines / immunology*
  • Influenza, Human / diagnosis
  • Influenza, Human / epidemiology
  • Influenza, Human / prevention & control*
  • Influenza, Human / virology
  • Male
  • Middle Aged
  • New Zealand / epidemiology
  • Outcome Assessment, Health Care*
  • Population Surveillance
  • Reverse Transcriptase Polymerase Chain Reaction
  • Seasons
  • Sentinel Surveillance
  • South Africa / epidemiology
  • Vaccination / statistics & numerical data*
  • Vaccine Potency*

Substances

  • Influenza Vaccines