Preparing for an Influenza Pandemic in Westminster Health and Community Services Overview and Scrutiny Committee 9 Oct 2006 Dr Margaret Guy Director of Public Health

What is a flu pandemic? Flu pandemics occur when a new influenza virus emerges which is able to: infect people; infect people; spread readily from person to person; spread readily from person to person; cause illness in high proportion of people infected; and cause illness in high proportion of people infected; and spread widely. spread widely.

Influenza virus An RNA virus An RNA virus Three types: A, B, and C Three types: A, B, and C A & B are major human pathogens: give rise to ‘normal’ epidemics in winter A & B are major human pathogens: give rise to ‘normal’ epidemics in winter Only influenza A virus is recognised as having the potential to cause a pandemic Only influenza A virus is recognised as having the potential to cause a pandemic

Influenza A subtypes H antigen - 16 different subtypes H antigen - 16 different subtypes N antigen - 9 different subtypes N antigen - 9 different subtypes Both antigens change over time, H more than N Both antigens change over time, H more than N  DriftMinor continuous changes in same subtype Results in epidemics - almost every winter  ShiftMajor abrupt change in subtype May result in pandemic as little/no immunity

Circulating influenza strains in humans and pandemics in 20 th Century H1N1 H2N2 H3N2 1918: “Spanish Flu” million deaths 1957: “Asian Flu” 1 million deaths 1968: “Hong Kong Flu” 1 million deaths

Domestic birdsMigratory water birds Hong Kong 1997, H5N1 Hong Kong and China 1999, H9N2 Netherlands 2003, H7N7 Hong Kong 2003, H5N1 Vietnam and Thailand, 2004 H5N1 Transmission of Avian Flu to humans

Emergence of pandemic strains Migratory water birds

Avian Flu - H5N1 First isolated from terns in 1961 in S. Africa First isolated from terns in 1961 in S. Africa Outbreaks in 8 countries in SE Asia during late 2003 and early 2004 Outbreaks in 8 countries in SE Asia during late 2003 and early 2004 From late June 2004 new deadly outbreaks reported in Cambodia, China, Indonesia, Malaysia Thailand Vietnam and Turkey From late June 2004 new deadly outbreaks reported in Cambodia, China, Indonesia, Malaysia Thailand Vietnam and Turkey These are ongoing These are ongoing

Mortality during the pandemic of  3 epidemic waves in fairly close succession  March 1918, Sept 1918, Feb 1919  Up to 40 million deaths world-wide, including…  198,000 excess civilian deaths in Britain  500,000 excess civilian deaths in USA A/H1N1 – Spanish influenza

Mortality in other 20 th century pandemics (A/H2N2) – Asian flu  USA, 80,000 excess deaths  Worldwide: Estimated 1.0 million deaths (A/H3N2) – Hong Kong flu  UK: 30,000 excess deaths (c/f 26,000 in )  Worldwide: Estimated 0.8 – 1.0 million deaths

People who consult their GP People infected with symptoms People infected without symptoms % 50% % % Morbidity associated with pandemic influenza

April 2005

WHO Influenza Pandemic Phases Inter-pandemic Period Inter-pandemic Period Phase 1 No new influenza virus subtypes detected in humans. Phase 1 No new influenza virus subtypes detected in humans. Phase 2 No new influenza virus subtypes detected in humans, but circulating animal influenza virus subtype poses substantial risk of human disease. Phase 2 No new influenza virus subtypes detected in humans, but circulating animal influenza virus subtype poses substantial risk of human disease. Pandemic Alert Period Pandemic Alert Period Phase 3 Human infection with new subtype but no new human-to- human spread, or, at most, rare instances of spread to close contact. Phase 4 Small cluster(s) with limited human-to-human transmission but spread highly localised, suggesting virus not well adapted to humans Phase 5 Large cluster(s) but human-to-human spread still localised, suggesting virus becoming increasingly better adapted to humans, but may not yet be fully transmissible (substantial pandemic risk). Pandemic Period Pandemic Period Phase 6 Pandemic phase: increased and sustained transmission in general population; second and further waves likely 3-9 months after previous wave has subsided Post Pandemic Period Post Pandemic Period Return to inter-pandemic period

Implications for the UK If there are cases in the UK during the pre-pandemic period, the international phases apply. If there are cases in the UK during the pre-pandemic period, the international phases apply. Once a pandemic has been declared (Phase 6), a four point UK-specific alert mechanism has been developed (consistent with alert levels used in other UK infectious disease response plans): Once a pandemic has been declared (Phase 6), a four point UK-specific alert mechanism has been developed (consistent with alert levels used in other UK infectious disease response plans): Alert level 1: Cases outside the UK Alert level 2: New virus isolated in the UK Alert level 3: Outbreak(s) in the UK Alert level 4: Widespread activity across the UK.

Influenza – transmission of infection Incubation period Incubation period 1-3 days Virus shedding Virus shedding 24 hours before symptoms and up to 9 days after onset of symptoms 24 hours before symptoms and up to 9 days after onset of symptoms Only considered to be infective when symptomatic Transmission Respiratory secretions - airborne droplet spread by coughing, sneezing or contaminated hands

Reducing the impact of a Flu Pandemic Immunisation against influenza Immunisation against influenza Pneumococcal immunisation Pneumococcal immunisation Measures to reduce the transmission of influenza Measures to reduce the transmission of influenza  Restriction of travel or mass gatherings  Action by individuals  Action by health and care staff  Action to reduce spread in residential facilities Antiviral drugs Antiviral drugs

Planning for a Flu Pandemic National National UK National Influenza Pandemic Committee (UKNIPC) National Director of Pandemic Influenza Preparedness London London London Health Pandemic Flu Steering Group London Pandemic Flu Coordinator Westminster Westminster Westminster Influenza Pandemic Committee Westminster Influenza Pandemic Coordinator

Local estimates of service demand (17-week pandemic wave) Per week* ** Total** New influenza cases 460 rising to 7590 (920 rising to 15180) 56120(112240) GP consultations 92 rising to 1516 (184 rising to 3032) 11261(22522) A&E presentations 23 rising to 379 (46 rising to 759) 2806(5612) Hospital admissions 2 rising to 44 (4 rising to 88) 363(726) Excess deaths assuming a 0.37% case fatality rate 2 rising to 28 (4 rising to 56) 209(418) Excess deaths assuming a 2.5% case fatality rate 12 rising to 190 (23 rising to 380) 1403(2806) *The highest figures are given for week 9 within a 17 week pandemic wave period ** Estimated 25% attack rate with 50% attack rate given in parenthesis

Service demand during worst 8 weeks of pandemic (weeks 5-12) Per week* ** Total** New influenza cases 3220 rising to 7590 (6440 rising to 15180) 45080(90160) GP consultations 653 rising to 1516 (1306 rising to 3032) 9064(18128) A&E presentations 161 rising to 380 (322 rising to 759) 2254(4508) Hospital admissions 16 rising to 44 (32 rising to 88) 276(552) Excess deaths assuming a 0.37% case fatality rate 12 rising to 28 (24 rising to 56) 168(336) Excess deaths assuming a 2.5% case fatality rate 81 rising to 190 (161 rising to 3797) 1127(2254) **Estimated 25% attack rate with 50% attack rate given in parenthesis

Planning for a Flu Pandemic in Westminster

Workstreams Westminster-wide work Westminster-wide work Joint work between all health service providers Joint work between all health service providers Joint work with Westminster City Council Joint work with Westminster City Council

Westminster-wide work Overarching Westminster Influenza Pandemic Contingency Plan Overarching Westminster Influenza Pandemic Contingency Plan Command and control structures Command and control structures Agreeing responsibility for local actions Agreeing responsibility for local actions + development of action cards Business continuity Business continuity Communications Strategy Communications Strategy Staff training Staff training Supplies and logistics Supplies and logistics Monitoring arrangements Monitoring arrangements Budgets Budgets

Joint work between health service providers Arrangements for administering antivirals and vaccine – Flu centres Arrangements for administering antivirals and vaccine – Flu centres Supporting self care Supporting self care Triage of those who seek advice Triage of those who seek advice Mounting the Primary Care Response Mounting the Primary Care Response Mounting the Secondary Response Mounting the Secondary Response Maintaining services for people who do not have influenza Maintaining services for people who do not have influenza Role of private hospitals and nursing homes Role of private hospitals and nursing homes Hospice care provision Hospice care provision Infection control measures Infection control measures Ensuring business continuity plans are complementary Ensuring business continuity plans are complementary

Joint work with Westminster City Council Flu centres – identification of suitable sites Flu centres – identification of suitable sites Mortuaries – including liaison with Coroner Mortuaries – including liaison with Coroner Joint work with Social Services in relation to the provision of services to people in receipt of PCT services and social services Joint work with Social Services in relation to the provision of services to people in receipt of PCT services and social services Ensuring business continuity plans are complementary Ensuring business continuity plans are complementary Provision of antivirals/vaccine for WCC essential staff Provision of antivirals/vaccine for WCC essential staff