2020 Weekly Influenza Surveillance Report Week Ending 22 August

Victorian Weekly Influenza Report Week ending: 22 August 2020

Summary

· Notified cases 1: o Cases in week ending 22 August 2020 are LOWER THAN the number of cases for the week prior o Cases (since 1 January 2020) are tracking LOWER THAN cases for the same time in 2019, and are BELOW EXPECTED LEVELS for this time of the year o Weekly notifications of influenza (since 1 April 2020) are trending: UNCHANGED o The predominant influenza type (and subtype) across the state is currently: Type A o National data indicate A/H1N1 is predominating o Geographical spread 2 is currently: SPORADIC o There were nil new respiratory outbreaks due to laboratory-confirmed influenza in residential aged care facilities reported in week ending 22 August 2020

· Vaccine distribution figures*: o Influenza vaccines distributed state-wide: 2,375,610 doses (as at 26 August 2020 ) * includes vaccines distributed as part of Commonwealth and Victorian Immunisation Programs * excludes vaccines purchased from the private market ______1. As of 1 September 2018, notification data includes only laboratory-confirmed influenza cases. As clinical information is no longer collected in the notification dataset, and timely mortality data are not available, number of deaths among all notified cases is not reported

2. Geographic spread: Sporadic – small numbers of laboratory-confirmed influenza cases reported, not above expected background level; Localised – laboratory-confirmed influenza detections above background level in less than 50% of the state; Regional – significant numbers of laboratory-confirmed influenza cases reported above background level in less than 50% of the state; Widespread – significant numbers of laboratory confirmed influenza cases reported above background level in equal to or greater than 50% of the state.

Report issued: 28 August 2020 8/27/2020 PHESS Influenza Summary: Victoria

NOTIFIED CASES Week ending Week ending Week ending 2020 YTD 2019 YTD 2018 YTD 2017 YTD 2019 Total 2018 Total 2017 Total 22-1 Aug 15 -2Aug 08 -3Aug  Influenza 7 16 10 4,746 50,988 3,519 18,512 69,586 11,622 48,301

Influenza A Influenza A and B Influenza B 20,000

15,000

10,000

Notifiedcases 5,000

July

May

June

April

March

August

January

October

February

December

November

September

September 2017 2018 2019 2020

Year-to-date (YTD) includes notifications received at DHHS up to and including: 22 August Data are subject to revision Data extracted: 27 August 2020 1/1 8/27/2020 By AgeGroup

Influenza: age groups, Victoria 2020

Age Group week ending week ending week ending most recent most recent 2020 2019 2018 2017 2017-2019 2020 2020 (years) 22wk-1 Aug 15wk-2 Aug 08wk-3 Aug weekly weekly year-to- year-to- year-to- year-to- year-to- compared with compared with change change date date date date date 2017-2019 2017-2019 average year-to-date year-to-date average average  00 to 04 1 1 1 -- 0% 395 5,411 301 1,519 2,410 ⛛ -84% 05 to 14 0 2 1 ⛛ -- 501 9,446 396 2,620 4,154 ⛛ -88% 15 to 64 3 9 6 ⛛ -67% 3,139 28,203 2,164 10,224 13,530 ⛛ -77% 65+ 3 4 2 ⛛ -25% 711 7,928 658 4,149 4,245 ⛛ -83% TOTAL ** 7 16 10 -56% 4,746 50,988 3,519 18,512 24,340 -81%

** TOTAL includes notified influenza cases where date of birth was reported

Influenza A Influenza A and B Influenza B 500

400

300

200

Notifiedcases

100

0 00-04 05-09 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85+ Age Group (years) 1/1 8/27/2020 LGA Map Influenza: Incidence by Local Government Area, Victoria 2020

1/1 27/08/2020 ROB Respiratory Outbreaks in Residential Aged Care Facilities

Influenza outbreaks in Residential Aged Care Facilities

40 Influenza A Influenza A and B Influenza B 30

Number of Outbreaks Number of 10

0 Jul 2017 Jan 2018 Jul 2018 Jan 2019 Jul 2019 Jan 2020 week ending

Resident cases, hospitalisations and deaths during Facilities are encouraged to report respiratory outbreaks due to respiratory viruses when there are influenza outbreaks in aged care by year reported to DHHS three resident cases within three days with sudden onset of the following symptoms:

respiratory - cough, sore throat or shortness of breath YEAR-TO-DATE Outbreaks Resident Cases Hospitalisations systemic - fever, malaise, headache or myalgia .  2020 13 97 6 Refer to Appendix for further details 2019 192 2512 254

2018 11 169 17 Includes cases, hospitalisations in residents with influenza-like illness in outbreaks in aged care 2017 122 2021 232 facilities where at least one resident had laboratory-confirmed influenza - some hospitalisations occurred in residents without laboratory-confirmed influenza.

1/1 8/27/2020 VEMD

The Victorian Emergency Minimum Dataset (VEMD) comprises Victorian Emergency Minimum Dataset de-identified demographic, administrative and clinical data detailing presentations at Victorian public hospitals with Emergency Department presentations for respiratory illness designated emergency departments. Data from the VEMD are received within seven working days.

The dataset includes three diagnoses. Any diagnosis with a prefix "J" is considered to be due to respiratory illness, but codes designating asthma (J45) have been excluded.

1,000

500

Presentations 0 Jan 2020 Feb 2020 Mar 2020 Apr 2020 May 2020 Jun 2020 Jul 2020 Aug 2020

1,000

500

Presentations 0 Jan 2019 Mar 2019 May 2019 Jul 2019 Sep 2019 Nov 2019

1,000

500

Presentations 0 Jan 2018 Mar 2018 May 2018 Jul 2018 Sep 2018 Nov 2018

1/1 27/08/2020 FluCAN FluCAN: Influenza Complications Alert Network Sentinel Hospital Surveillance Victoria

YEAR-TO-DATE Paediatric influenza Paediatric influenza % ICU for Paediatric Adult Influenza Adult Influenza ICU % ICU for Adult admissions * ICU admissions * Influenza Admissions Admissions Admissions Influenza Admissions 

2020 3 0 0.0 1 0 0.0 2019 591 64 11.0 797 61 7.7 2018 31 2 6.0 49 4 8.2 2017 492 52 10.6

* Data not available for paediatric influenza hospital admissions in 2017

The Influenza Complications Alert Network (FluCAN) is a rapid alert system for severe respiratory illness. The sentinel surveillance system is a national system (across major hospitals throughout Australia) providing both clinical and laboratory information for reported cases.

The following six Victorian hospitals are participating: The Alfred Hospital, Royal Melbourne Hospital, Monash Medical Centre, University Hospital Geelong, Royal Children’s Hospital and Monash Children’s Hospital.

1/1 27/08/2020 VicSPIN VicSPIN: Sentinel GP Surveillance for influenza-like illness VicSPIN sentinel GP consultation rate for ILI (per 1,000 patients)

ILI rate per 1,000per consultations rate ILI

21-Mar 28-Mar 04-Apr 11-Apr 18-Apr 25-Apr 02-May 09-May 16-May 23-May 30-May 06-Jun 13-Jun 20-Jun 27-Jun 04-Jul 11-Jul 18-Jul 25-Jul 01-Aug 08-Aug 15-Aug 22-Aug

week ending VicSPIN sentinel GP - influenza types and percentage of swabs which were influenza positive

A H1 % influenza positive 100 4

50 2

influenzapositive 0 0 %influenza positive 21-Mar 28-Mar 04-Apr 11-Apr 18-Apr 25-Apr 02-May 09-May 16-May 23-May 30-May 06-Jun 13-Jun 20-Jun 27-Jun 04-Jul 11-Jul 18-Jul 25-Jul 01-Aug 08-Aug 15-Aug 22-Aug week ending

In 2020, the Victorian Sentinel Practice Influenza Network (VicSPIN) surveillance program includes approximately 52 GPs from across Victoria who will submit weekly reports from April to October detailing the proportion of their consultations for patients with influenza-like illness and the proportion that were swabbed for virological testing. Refer to Appendix for further details and https://www.vidrl.org.au/surveillance/influenza-surveillance/ for full weekly reports. 1/1

Weekly Influenza Surveillance Report – APPENDIX

It is a Victorian statutory requirement that pathology services notify the Department of Health and Human Services (the department) of a case of laboratory-confirmed influenza within five days of confirmation. These data are stored in the department’s notifiable diseases database, the Public Health Event Surveil lance System (PHESS). During influenza season, data on Notified cases of notified cases are reported weekly. Numbers of confirmed influenza cases have risen with the widespread availability of influenza testing. As of 1 September 2018, medical practitioners laboratory - were no longer required to report influenza. confirmed influenza Further data on notifiable conditions may be found at: https://www2.health.vic.gov.au/public-health/infectious-diseases/infectious-diseases-surveillance/interactive-infectious-disease-reports

Reporting of respiratory outbreaks in aged care facilities to the department is not legislated but is encouraged. Samples are not collected and tested for all residents during outbreaks, but if Respiratory any case tests positive for influenza, the outbreak is deemed to be due to influenza. The cases included in this report are r esidents who experienced an influenza-like illness during the outbreaks reported course of the outbreak, but not all cases, hospitalisations and deaths are necessarily due to laboratory -confirmed influenza. to the Health Further information on management of respiratory outbreaks in residential and aged care facilites ma y be found at: https://www2.health.vic.gov.au/public-health/infectious-diseases /infection- Protection Branch control -guidelines/respiratory-illness-management-in-aged-care-facilities

The Victorian Sentinel Practice Influenza Network (VicSPIN ) is a sentinel general practitioner (GP) surveillance program funded by the department, and coordinated by the Epidemiology Unit of the Victorian Infectious Diseases Reference Laboratory (VIDRL) based at the Peter Doherty Institute for Infection and Immun ity. VIDRL is one of the department’s two public health The Victorian reference laboratories. Approximately 52 GPs submit weekly reports from April to October detailing the proportion of their consultations that were for patients with influenza-like illness and Sentinel Practice the prop ortion that were swabbed for virological testing. Testing is performed at VIDRL and the respiratory panel of viruses tested includes SARS-CoV-2. In 2020 s urveillance commenced Influenza Network (VicSPIN ) earlier than usual , with the first report in March.

Refer to https://www.vidrl.org.au/surveillance/influenza-surveillance/ for full weekly reports.

Influenza Complications Alert The Influenza Complications Alert Network (FluCAN) is a rapid alert system for severe respiratory illness. The sentinel surveillance system is a national system (across major hospitals Network throughout Australia) providing both clinical and laboratory information for reported cases. The following six Victorian hosp itals are participating: The Alfred Hospital, Royal Melbourne (FluCAN) Hospital, Monash Medical Centre, University Hospital Geelong, Royal Children’s Hospital and Monash Children’s Hospital.

The Victorian Emergency Minimum Dataset (VEMD) comprises de -identified demographic, administrative and clinical data detailing presentations at Victorian public hospitals with Victorian designated emergency departments. Data from the VEMD are received within seven working days. The dataset includes three diagnoses. Any diagnosis with a prefix "J" is considered to be Emergency due to respiratory illness excluding asthma. Minimum Dataset (VEMD) Full information on the VEMD can be found at : https://www2.health.vic.gov.au/hospitals-and-health-services/data-reporting/health-data-standards-systems/data-collections/vemd