Department of Human Services Avian influenza and pandemic preparedness Bruce McLaren Communicable Diseases Section Phone hour page

Avian influenza in birds Avian influenza in people DHS response to suspected cases Preparing for a pandemic in GP Overview of state/national plans Aims

Biology Influenza virus Changeable: Mutation – antigenic drift Reassortment – antigenic shift Haemagglutinin – binding to cells – virulence factor Neuraminidase – release of virus from cell Many species affected: horses, felines, mink, seals Interspecies infection: pigs, birds, humans

Type: Influenza A, B, (C) Subtype (for Flu A): HxNy Variants – site, year, number Biology

History Antigenic shift - Pandemics H1N1: million deaths, - approximately 2.5% mortality H2N H3N2 Antigenic drift – variable epidemics year to year eg 2005 A/New Caledonia/20/99 (H1N1); A/Wellington/1/2004 (H3N2); B/Shanghai/361/2002 or B/Jiangsu/10/2003

Avian influenza

Source: European Union

Avian influenza in humans Source – European Union

Source: European Union

Avian influenza – DHS and Victoria Current picture – “Overseas phase 3” –“human infection overseas with a new sub-type of influenza but no human to human spread or at most rare instances of spread to a close contact” Testing at DHS: Countries reporting avian influenza (bird or human) Plausible contact (animal, laboratory, patient) Notified cases: 64 since June 2005 Tested cases: 13 since June 2005

Summary of tested cases

Main features of tested cases First presentation: GP 10, hospital 3 Hospitalised - 8 Age range: 25 – 80 years; 9 Male 4 Female Countries visited: HK – 3, China – 3, Thailand – 3, Vietnam – 2, Indonesia – 1, Australia – 1 Occupation : Lab technician x 1, Lab assistant x 1, tourist x 11 Outcome – no isolate 5; influenza A (H3) 6; influenza A (nonH5) 1; picornavirus 1

Suspected avian influenza Risk factors Exposure Symptoms ý Isolate – asap – before presentation! ý Ring DHS re testing, transfer ý Alert hospital and ambulance in advance

Avian influenza –challenges in clinical practice Recognition: exposure history plus compatible illness (plus timelines) Forewarning of presentation – see at home if possible Unusual presentations: diarrhoea and fever, encephalitis Countries without apparent avian influenza (eg Iraq)

Anti viral medications M2 inhibitors eg amantadine (Flu A only) –Current H5N1 is resistant –Possible role in pandemic for treatment Neuraminidase inhibitors: oseltamivir (tablet, syrup), zanamivir (oral inhalation) –Prophylaxis: Oseltamivir: 75 mg daily up to 6 weeks After contact – begin asap, 10 days 50-70% effective

Anti-viral medications Oseltamivir –Treatment: 75 mg bd for 5 days within 48 hours of onset Reduce dose in severe renal failure (GFR <30 ml/min) Pregnancy and children <1 year – “no evidence” Nausea, vomiting, diarrhoea, hypersensitivity Effectiveness? Resistance?

Anti-viral medications Current situation: –National stockpile: 4 million packs and counting –State “stockpile” –Hospitals? –Practices? –Personal? –Travellers and expatriates

Pandemic influenza

Preparing for a pandemic in clinical practice Protect yourself and staff –Waiting room posters –Train receptionists –PPE: ON wash, mask, goggles, gown gloves OFF gloves, wash, goggles, gown, mask, wash Planning –Absentees –Appointments –Separation –Handling problems: demand, aggression

Preparing for a pandemic in clinical practice Immunisation of staff and high risk patients: –Current season influenza –Pneumococcal –Also for staff: MMR, ADT (boostrix - pertussis)

Victorian and national pandemic plans: overview Stages: actual pandemic will be phases 4 and 5 (overseas) and 6 (Australia) Waves – weeks or months apart Victoria – first 6-8 weeks – 2,000 – 10,000 deaths (usual avge. 700/week) - 6,000 – 25,000 admissions - 600,000 – 750,000 outpatients

Victorian and national pandemic plans: overview Strategy: –Preparedness ýContainment ýMaintenance of essential services Hospitals: –Designated hospitals (NPR and isolation) ýDedicated wards ýDedicated influenza hospitals ýFever clinics

Victorian and national pandemic plans: overview Primary care: –Business as usual? –Changed routines separation of clinics? Task force – home visits? –Fever clinics –Rotation of staff – six weekly? –Divisions, AMA, practice managers

Big pandemic issues Anti-virals: –Treatment: priorities? –Prophylaxis: contacts –Prophylaxis: essential services –Managed by Govt, dispensed by clinicians Vaccine –Pre-preparation –Effectiveness – almost certainly 2 doses –Timelines: weeks to months to develop –Rapid deployment

Thanks Bruce McLaren Communicable Diseases Section Phone Medical officer: 24 hour page