Surveillance of Influenza activity in Australia & New Zealand

This report provides a summary of surveillance data collected from around Australia and New Zealand. Regional reporting in some areas ceases when flu activity is low (out of season).

Australia

New South Wales

Week ending 31 October 2011

The rate of influenza-like illness (ILI) presentations to selected emergency departments was lower than the previous month but within the normal range for October.

58 cases with laboratory-confirmed influenza A – predominantly H3N2 – and 26 cases of influenza B were identified by sentinel laboratories. Rhinovirus was the most common respiratory virus identified by sentinel laboratories.

For more information: NSW Health - Infectious Diseases Alert

Queensland

Year to date 5 December 2011

Year to date (YTD) there have been 10,289 notifications of influenza in Queensland.

There were 25 notifications in the past week, with 31 in the week before. This is consistent with a decline in influenza activity in the region.

For more information: QLD Health - Preventable Diseases

South Australia

Week ending 17 November 2011

Thirteen cases of influenza were reported this week, consistent with 14 cases reported last week. Apart from two influenza B cases, all other cases were attributed to influenza A virus.

For more information: Communicable Diseases Control Branch

Tasmania

Review of 2011 Fly Season

Surveillance of influenza-like illness activity via FluTracking has now ceased for the year. Doctors are testing less for influenza; influenza diagnoses and notifications are now uncommon.

In 2011:

A total of 359 notifications of influenza were received from 1 January to 30 November. Influenza notifications peaked in weeks 30 to 34 (25 July–28 August) at approximately 26 notifications received per week.

Influenza A was responsible for 52 per cent of the total notifications (133 by PCR and 51 by serology). Of the PCR-based detections, 97 were sub-typed with:

• 78 per cent H1N1.
• 22 per cent H3N2.

Influenza B was responsible for 48 per cent of the notifications (156 by PCR and 16 by serology). An outbreak of Influenza B was notified from a northern residential-care facility in August.

An outbreak of Influenza A (not further typed) was notified from a southern residential-care facility in August.

There were significant differences in the strains of influenza virus causing disease in Tasmania as the season evolved.

During the early part of the 2011 season (mid-April to late-June) the predominant influenza strain was H1N1 (A). Notifications of Influenza B began to increase in early June, and predominated during the peak of the 2011 season (early-July to late-September), and notifications of H1N1 (A) also continued. As the 2011 season concluded, (early-October to early-November) notifications of both H1N1 (A) and Influenza B declined. A small number of H3N2 (A) notifications were received throughout the season.

For more information: DHHS Communicable Diseases - FluTas

Victoria

Reporting for Victoria will re-commence April 2012

 

For more information: Victorian Infectious Diseases Reference Laboratory

Western Australia

Week ending 11 December 2011

ILI presentations to SPN(WA) GPs and Perth Emergency Departments, and influenza laboratory detections made by PCR at PathWest QEII, decreased this week.

Influenza detections comprised 82% (9) A-H3 virus, and 18% (2) influenza B virus.

For more information: WA Virus Watch

Nationally

Dept of Health & Ageing

For the period to 31 December 2011

There has been a total of 26,892 laboratory confirmed notifications of Influenza in Australia in 2011 to the end of December. Notifications reached their highest level in August (7,668), with a notification rate of 412 (per 100,000). The peak in 2010 occured in September with 4,988 cases, and a notification rate of 220 per 100,000. Total notifications for the 2010 calendar year was 13,491.

For national data: National Notifiable Diseases Surveillance System

Australian Sentinel Practices Research Network (ASPREN)

ASPREN is a national syndromic surveillance program co-ordinated by the Discipline of General Practice at the University of Adelaide and The Royal Australian College of General Practitioners. One of the conditions under surveillance is influenza like illness (ILI). General practitioners participating in the ASPREN program contribute data on the proportion of consultations which are ILI related.

For the period 31 October 2011 to 13 November 2011

Reports were received from 71 GPs from 8 states and territories over the 2 week period to the 13th of November 2011, based on a total of 12,877 consultations.

Nationally, Influenza Like Illness (ILI) notifications decreased slightly over the period with 130 notifications.

ILI rates reported in this period increased with 10 cases per 1000 consultations. For the same reporting period in 2010, ILI rates were 12 cases per 1000 consultations.

The age and sex breakdown of ILI cases from 1st January 2011 to 13th of November 2011 show the most reported cases in working age adults, aged 20—49.

For more information: ASPREN

Flu Tracking

FluTracking is a pilot online health surveillance system which aims to detect epidemics of influenza. It is a joint initiative of The University of Newcastle, Hunter New England Area Health Service (NSW Health) and Hunter Medical Research Institute. Participation is voluntary and involves the completion of a weekly online survey during the influenza season. Data are collected on basic demographics, symptoms of ILI and absenteeism.

Week ending 25 September 2011

Across Australia, fever and cough was reported by 2.7% of vaccinated participants and 2.5% of unvaccinated participants. Fever, cough and absence from normal duties was reported by 1.5% of vaccinated participants and 1.4% of unvaccinated participants.

For participants this week, 4892/8650 (56.6%) have received the seasonal vaccine so far. Of the 1974 participants who identified as working face-to-face with patients, 1456 (73.8%) have received the vaccine.

For more information, or to enrol: Flu Tracking

New Zealand

Week ending 30 October 2011

Influenza-like illness (ILI) through sentinel surveillance was reported in all 20 District Health Boards (DHB) giving an overall national consultation rate of 7.9 per 100 000 (28 ILI consultations).

167 swabs were received from sentinel (4) and nonsentinel surveillance (163). 7 viruses were identified from non-sentinel surveillance. These were: B (3), A(H3N2) (2) and A(not sub-typed) (2).

For more information: Public Health Surveillance