Pandemic Influenza

Guidance for Pandemic Influenza: Infection Control in Hospitals and Primary Care Settings

UK Pandemic Influenza Contingency Plan

Operational Guidance for Health Service Planners

UK Operational Framework for Stockpiling, Distributing and Using Antiviral Medicines in the Event of Pandemic

Influenza

Department of Health, England Health Protection Agency

Pandemic flu: clinical management of patients with an influenza-like illness during an influenza pandemic.

Provisional guidelines from the British Infection Society, British Thoracic Society and Health Protection Agency

in collaboration with the Department of Health

ThoraxJanuary 2007

Influenza A

Influenza A• 1918 - H1N1 ‘Spanish flu’ 40 million deaths

• 1957 - H2N2 ‘Asian flu’ 2 million deaths

• 1968 - H3N2 ‘Hong Kong flu’ 1 million deaths

Recent epidemiological and virological changes from outbreaks of flu in Asia indicate that a pandemic is a definite possibility.

‘Avian flu’ - H5N1 - Endemic amongst birds in Asia. Since December 2003, 100 cases in humans

? adapting towards human transmission

Anxiety about H5

Pandemic

• New influenza A virus infects humans

• Spreads efficiently from human to human

• Causes significant illness in a high proportion of those infected

• No immunity in susceptible population - the disease spreads widely and rapidly

International phases

Inter-pandemic phases

1. No new influenza viruses detected in humans

2. Animal influenza virus sub-type poses substantial risk

International phases

Pandemic alert period

3. Human infections with a new sub-type but no human to human spread to a close contact

4. Small clusters with limited human to human transmission but spread is highly localised, suggesting that the virus is not well adapted to humans

5. Large clusters but human to human spread is still localised, suggesting that the virus is becoming increasingly better adapted to humans

International phases

Pandemic period

6. Increased and sustained transmission in general population

Post-pandemic period

7. Return to inter-pandemic period

International phases

Pandemic alert period

3. Human infections with a new sub-type but no human to human spread to a close contact

4. Small clusters with limited human to human transmission but spread is highly localised, suggesting that the virus is not well adapted to humans

5. Large clusters but human to human spread is still localised, suggesting that the virus is becoming increasingly better adapted to humans

UK Alert levels

1. Virus/cases only outside UK

2. Virus isolated in UK

3. Outbreaks in the UK

4. Widespread activity across the UK

Epidemiology• Mortality globally 2.4 - 7 million• Mortality UK - 50,000, possibly higher• Elderly, children and young adults• One month for virus to arrive in UK• Widespread cases within 2 weeks, peak 6

weeks• Possibly more than one epidemic wave• Clinical and Serological attack rates of 25%

and 50% respectively

Clinically

• Incubation 2-4 days

• Abrupt onset of fever

Clinically

• Cough• Malaise• Chills• Headache• Anorexia• Coryzal symptoms• Myalgia• Sore throat

Clinical case definition

The presence of fever and new (or, in those with chronic lung disease, worsening) cough of acute onset in the context of influenza circulating in the community

Complications

• Usually uncomplicated with acute symptoms resolving within 7 days

• Pneumonia

• Myocarditis

• Encephalitis/Myelitis/Guillaine-Barre

• Otitis media

Provision of care in the event of a Pandemic

Significant changes to usual practice in order to cater for the excess caseload over a period of a few weeks,

perhaps encompassing;

• Treatment of patients in the community by healthcare professionals other than their usual GP

• Treatment of patients in their own homes or intermediate care settings by their GP who, under usual circumstances, would have been admitted to hospital

• Treatment of severely ill cases in hospital by medical and nursing teams in areas of the hospital not normally used for providing such care.

Planning in Secondary Care

• Vaccination

• Anti-viral therapy for healthcare workers

• Infection control

• Capacity planning

Anti-virals

• Neuraminadase inhibitors – Oseltamivir, Zanamavir

• M2 Ion channel inhibitors – Amantadine

• Ribavirin

Infection control

• Timely recognition of cases• Preparedness, good stocks of disposables/equipment• Hand hygiene• Personal protection equipment• Containment of respiratory secretions• Triage and separation of cases

Infection control

• Restriction on health care workers• Restrictions on Patients• Restrictions on Visitors• Education of patients/visitors and staff• Occupational health, screening symptomatic workers• Non-clinical areas – laundry/linen

Infection controlSeparation

• Dedicated wards, adopting surgical beds• Reception areas• Visiting areas• Laboratory and X ray areas

Capacity

• Overall co-ordinator of hospital management during pandemic

• Supported by multi-disciplinary committee• Early discharge schemes• Triage• Cancellation of elective activity