Position paper endorsed by the Public Health Laboratory Network
27 November 2006
Reference Number: PHLN [PS]2006:001
Pathologists and Medical Laboratory Scientists
Veterinary Pathologists and Veterinary Laboratory Scientists
Researchers working with Influenza A viruses
This position statement arises from a discussion session on antiviral use for laboratory staff working with H5/Pandemic Influenza A virus at the October 2006 face-to-face meeting of the Public Health Laboratory Network (PHLN).
The Australian Health Management Plan for Pandemic Influenza (May 2006) describes the process and criteria for use of the National Medicines Stockpile (NMS) during an influenza pandemic. Stockpile components, which include antivirals, are distributed to states and territories according to a deployment plan, under memoranda of understanding between the Department of Health and each state and territory health department. Components of the stockpile will be used according to criteria agreed to by the Australian Health Protection Principal Committee (AHPPC) and underpinned by principles agreed to by Cabinet in December 2005 and April 2006.
The use of antiviral medication will depend on the phase of the outbreak in Australia and will be carefully monitored. Antiviral medication can be used for:
- treatment, with one 5 day course of medication
- prevention of infection after exposure, with one 10 day course of medication
- continuous prevention of infection, where more than 10 days of medication is required.
PHLN members were informed that the current decision-making structure stipulates that AHPPC would decide when laboratory testing will no longer be required to define cases, based on recommendations made by the Communicable Diseases Network Australia, although testing may still be requested by clinicians during all stages of a pandemic.
During maintenance phase, health care workers at high risk of continuous exposure and who are likely to spread the disease in the course of their work would be candidates for continuous pre-exposure prophylaxis.
Laboratory workers who handle certain types of specimens (notably viral cultures) are regarded as at high risk of exposure in the event of an accidental release of viral agent.
- In the event of a suspected exposure to cultured H5/Pandemic Influenza A virus, staff should be immediately assessed by an infectious diseases physician (or if appropriate, clinical microbiologist). If an exposure is deemed to have occurred the exposed staff should urgently be commenced on post-exposure antiviral prophylaxis. Oseltamivir 1 is recommended;
- Laboratory staff must adhere to the highest standards of procedures, including safe handling, appropriate use of PPE and biological safety cabinets, as well as an awareness of symptoms to reduce the risk of exposure;
- Laboratory staff should be considered candidates for pandemic strain immunisation once a suitable preparation becomes available (Laboratory staff could consider enrolling in clinical trials of vaccine or antiviral treatment/prophylaxis);
- Laboratory staff should ensure that they are vaccinated annually against seasonal human influenza, and with pneumococcal vaccine where indicated;
- Laboratory owners/proprietors/directors should consider a range of measures to ensure business continuity during stages of a pandemic;
- Laboratory staff including management, should stay up to date regarding potential availability of tests that allow confirmation of symptomatic or asymptomatic pandemic strain infection after treatment or prophylaxis with oseltamivir; and
- Public health laboratory operators should direct enquiries regarding access to antivirals to their State/Territory Chief Health Officer.
For information on accessing Jurisdictional Antiviral Stockpile Contact State and Territory Public Health Units.
- Should resistance to Oseltamivir be suspected or detected a suitable alternative agent, e.g., Zanamivir should be considered.