Gary K. Dowse

Epidemiological study of severe febrile reactions in young children in Western Australia caused by a 2010 trivalent inactivated influenza vaccine

Background The 2010 influenza vaccination program for children aged 6u2005months to 4u2005years in Western Australia (WA) was suspended following reports of severe febrile reactions, including febrile convulsions, following vaccination with trivalent inactivated influenza vaccine (TIV). Methods To investigate the association between severe febrile reactions and TIV, three studies were conducted: (i) rates of febrile convulsions within 72u2005h of receiving TIV in 2010 were estimated by vaccine formulation and batch; (ii) numbers of children presenting to hospital emergency departments with febrile convulsions from 2008 to 2010 were compared; and (iii) a retrospective cohort study of 360 children was conducted to compare the reactogenicity of available TIV formulations. Findings In 2010, an estimated maximum of 18u2008816 doses of TIV were administered and 63 febrile convulsions were recorded, giving an estimated rate of 3.3 (95% CI 2.6 to 4.2) per 1000 doses of TIV administered. The odds of a TIV-associated febrile convulsion was highly elevated in 2010 (p<0.001) and was associated with the vaccine formulations of one manufacturer—Fluvax and Fluvax Junior (CSL Biotherapies). The risk of both febrile convulsions (p<0.0001) and other febrile reactions (p<0.0001) was significantly greater for Fluvax formulations compared to the major alternate brand. The risk of febrile events was not associated with prior receipt of TIV or monovalent 2009 H1N1 pandemic vaccine. The biological cause of the febrile reactions is currently unknown. Interpretation One brand of influenza vaccine was responsible for the increase in febrile reactions, including febrile convulsions. Until the biological reason for this is determined and remediation undertaken, childhood influenza vaccination programs should not include Fluvax-type formulations and enhanced surveillance for febrile reactions in children receiving TIV should be undertaken.

Outbreak of Aeromonas hydrophila Wound Infections Associated with Mud Football

On 16 February 2002, a total of 26 people presented to the emergency department of the local hospital in the rural town of Collie in southwest Western Australia with many infected scratches and pustules distributed over their bodies. All of the patients had participated in a mud football competition the previous day, in which there had been ~100 participants. One patient required removal of an infected thumbnail, and another required surgical debridement of an infected toe. Aeromonas hydrophila was isolated from all 3 patients from whom swab specimens were obtained. To prepare the mud football fields, a paddock was irrigated with water that was pumped from an adjacent river during the 1-month period before the competition. A. hydrophila was subsequently isolated from a water sample obtained from the river. This is the first published report of an outbreak of A. hydrophila wound infections associated with exposure to mud.

Comparison of pandemic (H1N1) 2009 and seasonal influenza, Western Australia, 2009.

TOC summary: Infections were similar in terms of symptoms, risk factors, and proportion of patients hospitalized.

Household Responses to Pandemic (H1N1) 2009-related School Closures, Perth, Western Australia

Results from closures will determine the appropriateness and efficacy of this mitigation measure.

First reported case of transfusion-transmitted Ross River virus infection

PathWest Laboratory Medicine WA detected RRV IgM antibodies using an inhouse indirect immunofluorescence antibody (IFA) test, but no RRV antibodies were detected using an inhouse haemagglutination inhibition (HI) antibody test 10 days after blood donation. RRV IgM antibodies are detected by IFA testing within a few days of onset of illness and routinely persist for several weeks or, occasionally, months or years. IFA tests are less prone to false-positive results compared with enzyme immunoassays. The HI antibody test primarily detects IgG antibodies, which appear within several weeks but after the IgM response.

Geographic Information Systems used to describe the link between the risk of Ross River virus infection and proximity to the Leschenault estuary, WA.

Objective: To investigate the relationship between risk of Ross River virus (RRV) infection and proximity to mosquito‐breeding habitat surrounding a tidal wetland ecosystem in south‐west Australia.

Response to pandemic (H1N1) 2009 influenza in Australia - lessons from a State health department perspective.

This article reviews the lessons that can be learned by the health sector, in particular, and the public sector, more generally, from the governmental response to pandemic (H1N1) 2009 influenza A (pH1N1) in Australia during 2009. It covers the period from the emergence of the epidemic to the release of the vaccine, and describes a range of impacts on the Western Australian health system, the government sector and the community. There are three main themes considered from a State government agency perspective: how decisions were influenced by prior planning; how the decision making and communication processes were intimately linked; and the interdependent roles of States and the Commonwealth Government in national programs. We conclude that: (a) communications were generally effective, but need to be improved and better coordinated between the Australian Government, States and general practice; (b) decision making was appropriately flexible, but there needs to be better alignment with expert advice, and consideration of the need for a national disease control agency in Australia; and (c) national funding arrangements need to fit with the model of state-based service delivery and to support critical workforce needs for surge capacity, as well as stockpile and infrastructure requirements.

Risk of measles transmission on aeroplanes: Australian experience 2007-2011.

Objective: To quantify the risk of transmission of measles associated with infectious people who travelled on aeroplane flights to or within Australia.

An outbreak of chickenpox at a child care centre in Western Australia: Costs to the community and implications for vaccination policy

Objective: Between May and June 2002 an outbreak of chickenpox (CP) occurred at a child care centre in Perth, Western Australia. An epidemiological study was undertaken in order to determine the characteristics of the outbreak, assess vaccine effectiveness, and to define the direct and indirect costs associated with CP infections in young children.

Measles transmission by 'fly-in fly-out' workers in Australia.

Objective: To describe the outbreak investigation and control measures for a cluster of measles cases involving ‘fly‐in fly‐out’ (FIFO) workers on an off‐shore industrial vessel.