Virus WAtch Week Ending 24 August 2014

Influenza and Influenza-like Illnesses (ILI)

Summary: Most indicators of influenza activity decreased this week. Non-influenza respiratory virus activity is also declining.

• Most indicators of influenza activity, including notifications, proportion of positive laboratory tests for influenza, ILI presentations to sentinel general practitioners (GPs) and influenza-associated hospitalisations decreased this week, although Emergency Department ILI presentations and admissions increased.
• The majority of influenza viruses subtyped were influenza A/H1N1, but there are still a significant number of A/H3N2 detections, particularly associated with epidemic activity in the West Kimberley region (41% of A/H3N2 notifications this week). Influenza B continues to circulate at a low level.
• Detections of all non-influenza respiratory viruses decreased this week.

 Gastroenteritis

• Gastroenteritis presentations to sentinel GPs and EDs increased this week but remain close to average levels.

 Varicella and Viral Rashes

• Shingles and chickenpox presentations to sentinel GPs and EDs remain around expected levels.
• One case of measles was reported – the sixth secondary case linked to a traveller infected in the Philippines. No cases of rubella were reported this week.
• One case of mumps was confirmed in a contact of an adult traveller recently returned from Sri Lanka.

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