Virus WAtch Week Ending 2 August 2015

Megan Reilly

Virus WAtch Week Ending 2 August 2015

Influenza and Influenza-like Illnesses (ILI)

Summary: Indicators of influenza activity remain relatively steady, indicating we may be at or near the peak of the influenza season. Non-influenza virus activity continues to decline.

  • ILI presentations to sentinel general practitioners (GPs) and emergency departments (EDs) increased slightly this week but appear to have plateaued.
  • Influenza virus detections, notifications and percent positivity remain stable. The number and proportion of detections due to influenza B (63%) declined this week, with a relative increase in the proportion of influenza A/H3N2 (31%) cases.
  • Hospitalisations with confirmed influenza decreased this week, and are consistent with average levels for this time in recent seasons.  The proportion of hospitalisations due to influenza B decreased from 70% to 44% this week, with 56% of admissions now due to influenza A (mostly A/H3N2).
  • Non-influenza respiratory virus activity continued to decrease this week.


  • Gastroenteritis presentations to sentinel GPs and EDs are relatively steady and consistent with levels experienced previously at this time of the year.
  • Rotavirus detections increased this week.

Varicella and Viral Rashes

  • Shingles presentations to sentinel GPs increased above baseline level this week.
  • Chickenpox and shingles presentations to sentinel EDs are near or below baseline levels.
  • No cases of measles or rubella were confirmed.
  • Several further cases of mumps have been confirmed in the Kimberley region, primarily among Aboriginal children, teenagers and young adults. Most recent cases are residents of Broome or nearby communities, with some transmission now also occurring in the Pilbara region.