Flutracking weekly online community survey of influenza-like illness annual report, 2015.

Flutracking is a national online community influenza-like illness (ILI) surveillance system that monitors weekly ILI activity and impact in the Australian community. This article reports on the 2015 findings from Flutracking. From 2014 to 2015 there was a 38.

Influenza vaccine effectiveness in general practice and in hospital patients in Victoria, 2011-2013.

Objective: To compare influenza vaccine effectiveness in the general practice and hospital settings.

Design: Analysis of annual case test-negative studies.

Setting: Victorian sentinel hospitals and general practices, 2011-2013.

Transmission of the First Influenza A(H1N1)pdm09 Pandemic Wave in Australia Was Driven by Undetected Infections: Pandemic Response Implications.

Background: During the first wave of influenza A(H1N1)pdm09 in Victoria, Australia the rapid increase in notified cases and the high proportion with relatively mild symptoms suggested that community transmission was established before cases were identified. This lead to the hypothesis that those with low-level infections were the main drivers of the pandemic.

Methods: A deterministic susceptible-infected-recovered model was constructed to describe the first pandemic wave in a population structured by disease severity levels of asymptomatic, low-level symptoms, moderate symptoms and severe symptoms requiring hospitalisation.

Inter-Seasonal Influenza is Characterized by Extended Virus Transmission and Persistence.

The factors that determine the characteristic seasonality of influenza remain enigmatic. Current models predict that occurrences of influenza outside the normal surveillance season within a temperate region largely reflect the importation of viruses from the alternate hemisphere or from equatorial regions in Asia. To help reveal the drivers of seasonality we investigated the origins and evolution of influenza viruses sampled during inter-seasonal periods in Australia.

Understanding influenza vaccine protection in the community: an assessment of the 2013 influenza season in Victoria, Australia.

Background: The influenza virus undergoes frequent antigenic drift, necessitating annual review of the composition of the influenza vaccine. Vaccination is an important strategy for reducing the impact and burden of influenza, and estimating vaccine effectiveness (VE) each year informs surveillance and preventative measures. We aimed to describe the influenza season and to estimate the effectiveness of the influenza vaccine in Victoria, Australia, in 2013.

Systematic review of influenza A(H1N1)pdm09 virus shedding: duration is affected by severity, but not age.

Duration of viral shedding following infection is an important determinant of disease transmission, informing both control policies and disease modelling. We undertook a systematic literature review of the duration of influenza A(H1N1)pdm09 virus shedding to examine the effects of age, severity of illness and receipt of antiviral treatment. Studies were identified by searching the PubMed database using the keywords 'H1N1', 'pandemic', 'pandemics', 'shed' and 'shedding'.

The risk of fever following one dose of trivalent inactivated influenza vaccine in children aged ≥6 months to <36 months: a comparison of published and unpublished studies.

There are limited summary data published on the risk of fever and febrile seizures in children following influenza vaccination. We performed a review of the risk of fever and febrile seizures following receipt of trivalent inactivated influenza vaccine (TIV) in children aged ≥6 months to <36 months, searching PubMED and Google Scholar for English language articles from 2000 onwards, and initiated or ongoing unpublished studies since September 2007 using Clinicaltrials.gov.

Sevenfold rise in likelihood of pertussis test requests in a stable set of Australian general practice encounters, 2000-2011.

Objective: To better understand the role that diagnostic test-ordering behaviour of general practitioners has on current pertussis epidemiology in Australia.

Design And Setting: Analysis of Australian general practice encounter data (from the Bettering the Evaluation and Care of Health [BEACH] program) on 13 "pertussis-related problem" (PRP) codes that were most likely to result in a pertussis laboratory test request and Australian pertussis notifications data (from the National Notifiable Diseases Surveillance System [NNDSS]) for the period April 2000 to March 2011.

Main Outcome Measures: The change in the proportion of PRP general practice encounters with a pertussis test request between 2000 and 2011, and the change in national pertussis notifications over the same period.

The spread of influenza A(H1N1)pdm09 in Victorian school children in 2009: implications for revised pandemic planning.

Background: Victoria was the first state in Australia to experience community transmission of influenza A(H1N1)pdm09. We undertook a descriptive epidemiological analysis of the first 1,000 notified cases to describe the epidemic associated with school children and explore implications for school closure and antiviral distribution policy in revised pandemic plans.

Methods: Records of the first 1,000 laboratory-confirmed cases of influenza A(H1N1)pdm09 notified to the Victorian Government Department of Health between 20 May and 5 June 2009 were extracted from the state's notifiable infectious diseases database.

The significance of increased influenza notifications during spring and summer of 2010-11 in Australia.

Background & Objective: During the temperate out-of-season months in Australia in late 2010 and early 2011, an unprecedented high number of influenza notifications were recorded. We aimed to assess the significance of these notifications.

Methods: For Australia, we used laboratory-confirmed cases notified to the WHO FluNet surveillance tool; the percentage of these that were positive; notifications by state and influenza type and subtype; and surveillance data from Google FluTrends.

Moderate influenza vaccine effectiveness with variable effectiveness by match between circulating and vaccine strains in Australian adults aged 20-64 years, 2007-2011.

Background: Influenza vaccines are licensed annually based on immunogenicity studies. We used five sequential years of data to estimate influenza vaccine effectiveness (VE), the critical outcome in the field.

Methods: Between 2007 and 2011, we performed annual prospective test-negative design case-control studies among adults aged 20-64 years recruited from sentinel general practices in the Australian state of Victoria.

Adverse events associated with 2010 CSL and other inactivated influenza vaccines.

The 2010 trivalent influenza vaccine (TIV) manufactured by CSL Biotherapies (CSL) was associated with increased febrile reactions, including febrile convulsions, among Australian children. CSL is one of the few manufacturers that use deoxycholate as the virus-splitting agent in the manufacture of TIV. Clusters of adverse events following immunisation (AEFI) have been previously linked to other deoxycholate-split TIV formulations in Europe and Canada.

Effectiveness of H1N1/09 monovalent and trivalent influenza vaccines against hospitalization with laboratory-confirmed H1N1/09 influenza in Australia: a test-negative case control study.

We aimed to estimate the effectiveness of H1N1/09 containing influenza vaccines against hospitalization from influenza in Australia. We performed a test-negative case control study in patients hospitalized in 15 sentinel Australian hospitals between March and November 2010, comparing influenza vaccination (H1N1/09 monovalent or 2010 seasonal trivalent) in hospitalized patients with PCR-confirmed influenza compared to PCR-negative controls. Between March and November 2010, 1169 hospitalized patients were tested for suspected influenza, of which influenza vaccine status was ascertained in 165/238 patients with H1N1/09 influenza, 40/64 with seasonal influenza and 558/867 test negative controls; 24% of H1N1/09 cases, 43% of seasonal influenza cases and 54% of controls were vaccinated.

Effectiveness of seasonal influenza vaccine against pandemic (H1N1) 2009 virus, Australia, 2010.

To estimate effectiveness of seasonal trivalent and monovalent influenza vaccines against pandemic influenza A (H1N1) 2009 virus, we conducted a test-negative case-control study in Victoria, Australia, in 2010. Patients seen for influenza-like illness by general practitioners in a sentinel surveillance network during 2010 were tested for influenza; vaccination status was recorded. Case-patients had positive PCRs for pandemic (H1N1) 2009 virus, and controls had negative influenza test results.

Estimation of type- and subtype-specific influenza vaccine effectiveness in Victoria, Australia using a test negative case control method, 2007-2008.

Background: Antigenic variation of influenza virus necessitates annual reformulation of seasonal influenza vaccines, which contain two type A strains (H1N1 and H3N2) and one type B strain. We used a test negative case control design to estimate influenza vaccine effectiveness (VE) against influenza by type and subtype over two consecutive seasons in Victoria, Australia.

Methods: Patients presenting with influenza-like illness to general practitioners (GPs) in a sentinel surveillance network during 2007 and 2008 were tested for influenza.

Pandemic influenza H1N1 2009 infection in Victoria, Australia: no evidence for harm or benefit following receipt of seasonal influenza vaccine in 2009.

Conflicting findings regarding the level of protection offered by seasonal influenza vaccination against pandemic influenza H1N1 have been reported. We performed a test-negative case control study using sentinel patients from general practices in Victoria to estimate seasonal influenza vaccine effectiveness against laboratory proven infection with pandemic influenza. Cases were defined as patients with an influenza-like illness who tested positive for influenza while controls had an influenza-like illness but tested negative.