Influenza Activity Surveillance 2019
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). Please note that many people do not get tested for influenza and that there may also be some delays in reporting confirmed influenza cases.
Therefore data presented here may be underestimating influenza activity.
Click above for an up to date PDF of Australian Influenza Statistics.
Commonwealth Department of Health & Ageing
There have been a total of 304,314 laboratory confirmed notifications of Influenza in Australia for 2019, at the start of 6 November.
- ACT: 3,970
- NSW: 113,478
- NT: 1,483
- QLD: 66,785
- SA: 26,044
- TAS: 3,001
- VIC: 66,745
- WA: 22,808
For more national data: National Notifiable Diseases Surveillance System
Week ending 20 October 2019
- Influenza activity continues to decline and is now at inter-seasonal levels.
- Respiratory presentations to NSW emergency departments continue to decrease and are within the usual range for this period.
- Both influenza A and B strains continue to decline.
Summary for this reporting week:
Hospital surveillance – ILI presentations to EDs decreased and are within the usual range for this time of year.
Laboratory surveillance – overall respiratory testing and the influenza laboratory test positive rate (4.2%) both declined.
Community surveillance – influenza activity continued to decrease across the State. Three outbreaks were reported in residential aged care facilities.
Death surveillance – seven influenza deaths were reported. People who die with influenza may have other underlying illnesses, and surveillance captures only a proportion of people who die from influenza.
National surveillance – declining influenza activity; overall clinical severity rated as low.
2020 Southern Hemisphere influenza vaccine announced:
WHO influenza vaccine strain recommendations – Northern Hemisphere, 2019-20
The WHO Consultation on the Composition of Influenza Vaccines for Use in the 2019-20 Northern Hemisphere Influenza Season was held in Beijing on 18-20 February 2019.
From this meeting it was recommended that egg based quadrivalent vaccines for use in the 2019-2020 northern hemisphere influenza season contain the following:
- an A/Brisbane/02/2018 (H1N1)pdm09-like virus;
- an A/Kansas/14/2017 (H3N2)-like virus;
- a B/Colorado/06/2017-like virus (B/Victoria/2/87 lineage); and
- a B/Phuket/3073/2013-like virus (B/Yamagata/16/88 lineage).
It was also recommended that the influenza B virus component of trivalent vaccines for use in the 2019-2020 northern hemisphere influenza season should be a B/Colorado/06/2017-like virus of the B/Victoria/2/87-lineage.
In light of recent changes in the proportions of genetically and antigenically diverse A(H3N2) viruses, the recommendation for the A(H3N2) component was announced on 21 March. More details about the most recent influenza vaccine recommendations can be found at: http://www.who.int/influenza/vaccines/virus/en/
For more information: NSW Health – Infectious Diseases Alert
Week ending 13 October 2019
Summary of the year so far:
YTD positive tests for influenza: 66,135
Influenza A: 54,001 [A(H1N1) 970; A(H3N2) 2,867; subtype unavailable 50,164]
Influenza B: 12,134 [Victoria 191; Yamagata 14; Lineage Unavailable 11,929]
YTD hospitalisations: 3,012
YTD percentage of tests positive: 19.4%
For the week 7 – 13 October:
Influenza notifications: 389
Influenza A: 251 [A(H1N1) 2; A(H3N2) 7; Subtype unavailable 242]
Influenza B: 138 [Victoria 0; Yamagata 0; lineage unavailable 138]
Influenza hospitalisations for the week: 16
Percentage of test positive for the week: 6.9%
For more information: QLD Health – Preventable Diseases
13 – 20 October 2019
From 1 January to 19 October 2019, there were 25,754 notifications of influenza reported to the Communicable Disease Control Branch, compared with 3,916 cases reported for the same period last year.
Of these notifications:
- 14,180 were in females and 11,574 were in males
- The age range is <1 year – 105 years, with a median age of 31 years
- 21,801 cases (85%) were due to influenza A virus and 3,953 cases (15%) were due to influenza B virus
- 2,317 cases (9%) were hospital inpatients
- One hundred and five cases (0.41%) were reported to have died from influenza virus infection (age range 15 – 100 years).
For more information: Communicable Diseases Control Branch
August 2019 update
This surveillance report describes influenza activity in Tasmania during the period 1 January to 31 August 2019.
- Community syndromic surveillance in Tasmanian suggested influenza-like illness activity that was stable during August 2019 and decreased compared to during July.
- Laboratory-confirmed influenza notifications peaked at 180 cases during the third week of August (week 33). Notifications during August were similar for this time of year compared to previous years.
- Influenza testing increased by 5 per cent during August compared to during July. Testing since the start of 2019 has been 2.5 times the amount of testing conducted during the same period of 2018.
- The proportion of tests positive for influenza peaked during the third week of August.
- Two hundred and fifteen patients have been admitted to the Royal Hobart Hospital with influenza between 1 April and 30 August 2019.
- Influenza activity across Australia during August 2019 was reported to be lower than the average of previous years, following an apparent peak in activity in early July. Clinical severity for the season to date across Australia, as measured through the proportion of patients admitted directly to intensive care, and deaths attributed to influenza, is low.
Notifications of laboratory-confirmed Influenza to Public Health Services
There were 560 cases of influenza notified in Tasmania during August 2019. Between 2015 and 2018 an average of 478 cases of influenza were notified during the month of August.
Since 1 January 2019 a total of 2 491 cases of influenza have been notified.
During August weekly influenza case numbers increased to a peak of 180 cases before decreasing to 112 cases
Five per cent more influenza tests were conducted in Tasmania during August 2019 than during July: 2,220 tests compared to 2,120 tests during July. The highest number of influenza tests occurred during the third week of August (587 tests).
Since the start of 2019 influenza testing conducted by Tasmanian laboratories has been significantly greater than previous years. Between 1 January and 31 August 2019 a total of 11 374 influenza PCR tests were reported by laboratories: 2.5 times the testing conducted during the same period of 2018 (4,538 tests).
Proportion of tests positive for influenza
The weekly proportion of tests positive for influenza peaked during the third week of August (28 per cent) before declining to 21 per cent at the end of the month.
During 2014 to 2018, on average, 25 per cent of weekly influenza tests were positive during August (range one to 49 per cent positive).
For more information: Communicable Diseases Prevention – FluTAS
Week ending 27 October 2019
Overview: The 2019 influenza season so far
Influenza-like illness (ILI) continues to be below the average threshold this week.
The total ILI proportion measured by VicSPIN this week is slightly higher than at the same time in 2018 but lower than at the same time in 2017.
The number of notified cases of laboratory confirmed influenza is almost eight times higher than by the same time in 2018 and almost 1.5 times higher than in 2017.
The majority of notified cases over the season have been type A (76%), and type A cases are older than type B cases.
The ratio of type A to B has shifted in the last four weeks, with type A decreasing to 64% of notifications and type B comprising 36%.
Three swabs were received from VicSPIN this week, of which 33% (1 swab) were positive for influenza. The average for the season is 32%.
To date, influenza A(H3) was co-detected with A(H1N1)pdm09 in one case. In eight additional cases, influenza was co-detected with another respiratory virus.
For more information: Victorian Infectious Diseases Reference Laboratory or Victorian State Health Department
Week ending 27 October 2019
INFLUENZA AND INFLUENZA-LIKE ILLNESSES (ILI)
Indicators of influenza activity were below levels usually reported during this time of year in WA.
ILI activity at sentinel GPs remained low in the past week.
ILI presentations and admissions at sentinel EDs increased slightly in the past week.
PathWest influenza detections and test percent positivity were at low levels for this time of year.
Influenza A accounted for 56% of influenza detections at PathWest in the past week. Of the influenza A cases that were subtyped, all were influenza A/H3. Influenza B accounted for 44% of detections.
For more information: WA Virus WAtch
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.
9 – 22 September 2019
- Influenza-like-illness levels are decreasing
- 27 Cases of influenza have been detected in this reporting period: 19 x Influenza A and 8 x Influenza B
- 21% Influenza positivity during the reporting period.
- 1179 Cases of influenza have been detected this year: 950 x Influenza A and 229 x Influenza B
Reports were received from 360 reporters from 8 states and territories during the reporting period. During weeks 37 and 38 reporters saw a total of 53,324 patients.
Nationally, ILI notifications greatly decreased during the period with 336 notifications being reported in weeks 37—38. ILI rates reported in this period decreased to 7 and 8 cases per 1000 consultations (weighted) in weeks 37 and 38 respectively. This was much lower than the previous fortnight where rates were 11 cases per 1000 consultations. For the same reporting period in 2018, ILI rates were lower at 7 and 5 cases per 1000 consultations for weeks 37 and 38.
(Baseline ILL < 3 & 4 in 1000 consultations, Normal 4< ILL rate <24).
For more information: ASPREN
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 13 October 2019
This week influenza-like illness activity is lower than the 5 year average.
36,256 participants this week
(Data received up to 09:00 AM, Thursday 17 October)
Fever and cough: 1.2% this week (lower than 5 year average and decreasing)
Flu Symptom Activity by vaccination status:
0.3% lower fever and cough in unvaccinated group this weekInfluenza-like illness Severity:
28.8% of participants with fever and cough sought medical advice this week
Vaccination rates: 77.7% overall
For more information, or to enrol: Flu Tracking
Week ending 29 September 2019
In the last week of seasonal influenza surveillance for the year, indicators of influenza-like illness (ILI) activity in the community have remained low. Both ILI activity and the rate of people presenting to general practices (GP) with ILI who test positive for influenza virus are below the baseline level. Influenza A(H3N2) and B/Victoria viruses are co-circulating in the community and influenza A viruses are still predominating in hospitals. Virology reports indicate there has been a mutation in the influenza B/Victoria virus strain circulating in New Zealand during the 2019 season. This is expected to reduce the 2019 seasonal vaccine effectiveness for this influenza virus strain.
National indicators of community influenza-like illness (ILI) activity have mostly continued to decrease over the past few weeks.
Indicators of severity remain below seasonal baseline levels. Activity in Intensive Care Units is low.
For more information: NZ Flu Surveillance