Virus WAtch Week Ending 10 August 2014

Influenza and Influenza-like Illnesses (ILI)

Summary: Most indicators of influenza activity increased this week, but this was largely due to an epidemic of influenza A/H3N2 in the West Kimberley region, with relatively steady activity elsewhere. Overall non-influenza respiratory virus activity is declining.

• Indicators of influenza activity, including notifications, proportion of positive laboratory tests for influenza and influenza-associated hospitalisations increased this week.
• ILI presentations to sentinel general practitioners (GPs) decreased, but data were incomplete.
• The majority of influenza viruses subtyped were influenza A/H1N1, but there was an increase in A/H3N2 detections (primarily in the West Kimberley region). Influenza B continues to circulate at a low level.
• Overall detections of non-influenza respiratory viruses decreased this slightly week.

 Gastroenteritis

• Gastroenteritis presentations to sentinel GPs increased while ED presentations remain steady and below baseline.

 Varicella and Viral Rashes

• Shingles presentations to sentinel GPs and EDs remain at or just above expected levels, but chickenpox presentations remain low.
• Four cases of measles were confirmed in Albany adolescents with uncertain vaccination status who were contacts of an overseas-acquired case No confirmed cases of rubella or mumps were reported.

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