# 4097
From the eMJA (Medical Journal of Australia) three rapid online publications tonight regarding the southern hemisphere’s recent pandemic flu season.
The first study falls under the category of `lessons learned’ by clinicians during this past summer’s pandemic wave in Australia, and implications for change in pandemic policies.
The second study looks at the epidemiology and demographics of the pandemic, and clearly indicates the age-shift in hospitalized patients.
The third study looks at the hospitalizations of adult patients and concludes that the severity of illness seen with the novel H1N1 virus was comparable to that seen with seasonal flu. The primary differences seen were that those patients with novel (H1N1) tended to be younger and less immunocompromised.
Links and excerpts from their abstracts follow:
The rational clinician in a pandemic setting
David A Bradt and Joseph Epstein
Abstract
- Pandemic (H1N1) 2009 influenza has generated many controversies in Australia around case definitions, laboratory diagnosis, case management, medical logistics and travel restrictions.
Our experience as clinical advisers in the Victorian Department of Human Services Emergency Operations Centre suggests the following:
Case definitions may change frequently, and will tend to become more clinically specific over time.
Early in a pandemic, laboratory diagnosis plays a critical role in case finding and pathogen identification.
Later in the pandemic, standardised case management applied to well crafted case definitions should reduce reliance on the diagnostic laboratory in clinical management. The diagnostic laboratory will remain critical to monitoring disease surveillance, pathogen virulence, and drug susceptibility.
Medical logistics will continue to challenge pandemic managers as the health sector struggles to do the most good for the greatest number of people.
Travel restrictions remain scientifically controversial public health recommendations.
Issues of scalability (escalation and de-escalation of the response) relating to virus lethality need to be resolved in current pandemic planning.
Ranil D Appuhamy, Frank H Beard, Hai N Phung, Christine E Selvey, Frances A Birrell and Terry H Culleton
Abstract
- A graded public health response was implemented to control the pandemic (H1N1) 2009 outbreak in Queensland.
Public health measures to contain the outbreak included border control, enhanced surveillance, management of cases and contacts with isolation or quarantine and antivirals, school closures and public education messages.
The first confirmed case in Australia was notified on 8 May 2009, in a traveller returning to Queensland from the United States.
In Queensland, 593 laboratory-confirmed cases were notified with a date of onset between 26 April and 22 June 2009, when the Protect phase of the Australian Health Management Plan for Pandemic Influenza was implemented; 16 hospitalisations and no deaths were reported during this time.
The largest number of confirmed cases was reported in the 10–19-years age group (167, 28% of cases), followed by the 20–29-years age group (153, 26% of cases).
With ongoing community transmission, the focus has shifted from public health to the clinical domain, with an emphasis on protecting vulnerable groups.
Considerable resources have been invested to prevent and control the spread of disease in Indigenous communities in Far North Queensland.
The capacity of clinical services to cope with increased admissions, the potential for widespread antiviral resistance, and rollout of mass vaccination campaigns remain future challenges.
Age distribution of Lab confirmed H1N1 cases clearly showing the age-shift to young adults and children.
Ya-Shu Chang, Sebastiaan J van Hal, Peter M Spencer, Iain B Gosbell and Peter W Collett
Objective: To compare the patient characteristics, clinical features and outcomes of adult patients hospitalised with pandemic (H1N1) 2009 influenza and seasonal influenza.
Design and setting: Retrospective medical record review of all patients admitted to Liverpool Hospital, Sydney, with laboratory-confirmed influenza from the initiation of the “PROTECT” phase of the pandemic response on 17 June until the end of our study period on 31 July 2009.
Main outcome measures: Severity of illness; requirement for admission to the intensive care unit (ICU) and/or invasive ventilation; mortality.
Results: Sixty-four adults were admitted to Liverpool Hospital with influenza, 48 with pandemic (H1N1) 2009 influenza and 16 with seasonal influenza. Thirteen patients were admitted to the ICU. Seven required invasive ventilation, with 2 patients requiring ongoing extracorporeal membrane oxygenation (ECMO). Five patients died (mortality rate, 8%) with two deaths occurring after the study period. Patients with pandemic (H1N1) 2009 influenza were younger and less likely to be immunocompromised than patients with seasonal influenza. However, the clinical features of pandemic (H1N1) 2009 influenza and seasonal influenza were similar.
Conclusions: Our findings show that the clinical course and outcomes of pandemic (H1N1) 2009 influenza virus are comparable to those of the current circulating seasonal influenza in Sydney. The high number of hospital admissions reflects a high incidence of disease in the community rather than an enhanced virulence of the novel pandemic influenza virus.
