Virus WAtch Week Ending 12 July 2015

Megan Reilly

Virus WAtch Week Ending 12 July 2015

Influenza and Influenza-like Illnesses (ILI)

Summary: ILI activity and influenza virus detections decreased this week, but seasonal activity is on-going.

  • ILI presentations to sentinel emergency departments (EDs) and sentinel general practitioners (GPs) decreased this week, possibly a school holiday effect.
  • Hospitalisations with confirmed influenza have been relatively steady over recent weeks, at around 10 per 1000 admissions, over 50% due to influenza B virus.
  • Influenza B viruses (69%) and influenza A/H3N2 (26%) viruses remain the dominantly detected subtypes. The influenza B strains currently circulating are around 80% Yamagata lineage, matching the trivalent influenza vaccine strain.
  • Non-influenza respiratory virus activity increased this week, with respiratory syncytial virus activity remaining particularly high.


  • Gastroenteritis presentations to sentinel GPs and EDs are relatively steady and consistent with levels experienced previously at this time of the year.
  • Rotavirus detections remain high. Rotavirus has caused recent outbreaks of gastroenteritis in residential care and childcare settings in metropolitan Perth.

Varicella and Viral Rashes

  • Chickenpox and shingles presentations to sentinel EDs and GPs are near or below baseline levels.
  • No cases of measles or rubella were notified.
  • Several further cases of mumps have been confirmed among Aboriginal children, teenagers and young adults in the Kimberley region, including in Broome.