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 310,011 laboratory confirmed notifications of Influenza in Australia for 2019, at the start of 17 December.
- ACT: 4,020
- NSW: 115,500
- NT: 1,638
- QLD: 67,639
- SA: 26,862
- TAS: 3,109
- VIC: 68,176
- WA: 23,067
For more national data: National Notifiable Diseases Surveillance System
November Report 2019
- Influenza activity remains at low inter-seasonal levels with a stable trend.
- Respiratory presentations to NSW emergency departments continued to decrease but remained above the historical range in activity.
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
1 – 7 December 2019
There were 172 notifications of influenza reported this week. Cases comprised of 76 males and 96 females, with a median age of 19 years. Year-to-date there have been 26,768 notifications of influenza compared with 5,465 cases reported for the same period last year. In 2019, 22,272 cases have been attributed to influenza A virus and 4,496 cases have been attributed to influenza B virus.
For more information: Communicable Diseases Control Branch
September 2019 update
This surveillance report describes influenza activity in Tasmania during the period 1 January to 30 September 2019.
- Community syndromic surveillance in Tasmanian suggested low and decreasing influenza-like illness activity during September.
- Laboratory-confirmed influenza notifications decreased during September to 59 cases during the last week of the month (week 39). Notifications during September were 27 per cent lower than the same month of previous years.
- Influenza testing decreased by 17 per cent during September compared to during August. 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 decreased steadily during September.
- Two hundred and thirty-five patients have been admitted to the Royal Hobart Hospital with laboratory-confirmed influenza between 1 April and 4 October 2019.
- Influenza activity across Australia during September 2019 was reported to be lower than the average of previous years, and consistent with activity that follows the peak of the influenza season. 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.
FluTracking (Community Syndromic Surveillance)
FluTracking recommenced on Monday 8 April 2019, three weeks earlier than usual due to increased influenza activity across Australia. An average of 3 750 Tasmanians are participating each week, an increase on 2018 participation (3 150 Tasmanians per week).
During September 2019, reports of influenza-like illness (fever plus cough) in Tasmanian participants decreased from 1.9 per cent (week 36) to 1.1 percent (week 39).
Seventy-six per cent of participants with fever and cough during September also reported absenteeism from normal duties. This reported absenteeism was similar to August (75 per cent).
Notifications of laboratory-confirmed Influenza to Public Health Services
There were 363 cases of influenza notified in Tasmania during September 2019. Between 2015 and 2018 an average of 495 cases of influenza were notified during the month of September.
Since 1 January 2019 a total of 2 856 cases of influenza have been notified.
During September weekly influenza case numbers decreased from 121 cases (week 36) to 59 cases (week 39)
Influenza testing conducted in Tasmania decreased during September 2019. During September 1 849 tests were conducted compared to 2 221 tests during August: a decrease of 17 per cent.
Since the start of 2019 influenza testing conducted by Tasmanian laboratories has been significantly greater than previous years. Between 1 January and 30 September 2019 a total of 13 154 influenza PCR tests were reported by laboratories: 2.5 times the testing conducted during the same period of 2018 (5 262 tests).
Proportion of tests positive for influenza
The weekly proportion of tests positive for influenza decreased during September from 22 per cent to 14 per cent at the end of the month.
For more information: Communicable Diseases Prevention – FluTAS
Week ending 3 November 2019
Overview: The 2019 influenza season so far
Influenza-like illness (ILI) is well below the average threshold for the final reporting week of 2019.
The total ILI proportion measured by VicSPIN this week is similar to the final reporting week in 2018 but lower than in 2017.
The number of notified cases of laboratory confirmed influenza is over 7.5 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 66% of notifications and type B comprising 34%.
Five swabs were received from VicSPIN this week, of which 20% (1 swabs) 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 8 December 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 at sentinel EDs remained stable in the past week, while admissions decreased.
PathWest influenza detections and test percent positivity were at levels usually reported at this time of year.
Influenza A accounted for all influenza detections at PathWest in the past week, comprising 75% influenza A/H1, 8% influenza A/H3 and 17% influenza A/not subtyped.
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.
21 October – 3 November 2019
- Influenza-like-illness levels are decreasing
- 8 Case of influenza have been detected in this reporting period: 4 x Influenza A and 4 x Influenza B
- 17% Influenza positivity during the reporting period
- 1211 Cases of influenza have been detected this year: 968 x Influenza A and 243 x Influenza B
Reports were received from 351 reporters from 8 states and territories during the reporting period. During weeks 43 and 44 reporters saw a total of 51,899 patients.
Nationally, ILI notifications greatly decreased during the period with 86 notifications being reported in weeks 43—44. ILI rates reported in this period decreased to 2 cases per 1000 consultations (weighted) in weeks 43 and 44. This was lower than the previous fortnight where rates were 3 cases per 1000 consultations. For the same reporting period in 2018, ILI rates were similar at 3 cases per 1000 consultations for weeks 43 and 44 respectively.
(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 20 October 2019
This week influenza-like illness activity is low.
37,624 participants this week
(Data received up to 09:00 AM, Thursday 24 October)
Fever and cough: 1.3% this week (flu-like illness activity is low)
Flu Symptom Activity by vaccination status:
0.1% lower fever and cough in unvaccinated group this weekInfluenza-like illness Severity:
33.6% of participants with fever and cough sought medical advice this week
Vaccination rates: 77.7% overall
For more information, or to enrol: Flu Tracking
2019 ANNUAL INFLUENZA SUMMARY
This report provides an overview of the influenza season in New Zealand in 2019.
Further information and figures are available here.
Information on the influenza surveillance systems in New Zealand is available here.
SUMMARY OF 2019 SEASON
Influenza A(H3N2) and influenza B/Victoria co-circulated in New Zealand during the 2019 influenza season. Influenza A(H3N2) viruses often cause relatively more illness in elderly populations, whereas Influenza B viruses often affect younger and school aged children relatively more. In the 2019 season influenza A viruses were more frequently detected in hospitalised patients and influenza B/Victoria was more frequently detected in the community.
Community influenza related activity started and peaked earlier in 2019 than in recent seasons, but remained at a low level overall.
Severe acute respiratory infection (SARI) hospitalisation rates also increased earlier than in recent years, with similar levels of SARI hospitalisation to other recent years.
Over the influenza season (weeks 18–39), over 50% of samples tested in the community and just under 30% of samples tested in hospitals were influenza positive, this is one of the highest positivity rates observed in recent years and indicates that a higher proportion of viral respiratory illnesses during the 2019 winter were due to influenza than usually detected.
The severity of illness as measured by the ratio of influenza associated intensive care unit (ICU) admissions compared with influenza associated hospitalisations was low, which is similar to other influenza A(H3N2) predominant years.
The 2019 publically funded influenza vaccines available in New Zealand were a good match for the circulating strains. There was a genetic mutation in the influenza B/Victoria virus circulating during the season. However, this change had no discernible impact on vaccine effectiveness.
For more information: NZ Flu Surveillance