Date post: | 18-Jun-2015 |
Category: |
Healthcare |
Upload: | wirralct |
View: | 115 times |
Download: | 1 times |
Flu Through the AgesDr Katy Kidd
Retired Medical Director and Director of Infection Prevention and Control at Wirral PCT
Definition: Greek "All the people"
A new or long dormant infection
Spreads easily from person to person
Spreads to many countries/continents
Normally causes serious illness and death
There is a formal WHO definition which has varied at times, this includes 6 phases in the development of an influenza pandemic
Planning is based on these phases
Pandemics
1918 "Spanish Flu“ H1N1, 20 to 50 million dead, affected all age groups
1957 " Asian Flu" H2N2, 1.5 million dead, first wave affected children particularly, second wave elderly
1968 " Hong Kong Flu" H3N2, 1 million dead, mainly elderly affected
2009 " Swine Flu" H1N1, 284,500 dead, mainly affected pregnant women, those with pre-existing conditions
Influenza Pandemics of the Last Century
Virus in birds ( avian flu)...mutated...in humans...spread to pigs
“Parent” virus to subsequent pandemics
Affected 40% of world population
Onset of symptoms very fast
3 waves◦ Spring/summer 1918◦ Autumn 1918◦ Spring 1919
Rapid international spread encouraged by wartime/post war troop movements
Killed more people than First World War
1918 Spanish Flu
Genetic reassortment between the existing H1N1 virus and an avian H2N2 influenza virus
Started in China in February 1957, within six months, the pandemic spanned the entire globe
Cases were concentrated in school aged children and those crowded together
In the UK the impact on mortality was in the elderly
Appeared to be over end of 1957, 2nd wave in early 1958 which caused high rates of illness and increased fatalities
The 2 waves together affected some 40-50% of people
1957 Asian Flu
Resulted from genetic reassortment and arose in Southeast Asia, started in China July 1968, spread to Hong Kong same month, spreading rapidly across the whole world
Half a million cases were reported in Hong Kong in just two weeks
Identified as a novel influenza A subtype, H3N2, in August 1968
Reached the US in September 1968, via US Marines returning from service in Vietnam
Vaccine manufacture began within two months of the virus being isolated
1-3 million fatalities, of which over 30,000 were from the UK
1968 Hong Kong Flu
Antibiotics ◦Mid 1940s (military) ◦Late 1940s (General)
Vaccines
◦Early 1940s (early versions, US military) ◦1960s (general, including UK)
Antivirals
◦1999 specific flu antivirals (oseltamivir and zanamivir)
Influenza Prophylaxis and Treatment
Expected, as longest previous interval between pandemics was 39 years
Led by WHO, many countries started planning in 2005
Avian Flu expected, probably arising in Far East
UK took risk very seriously, on a par with terrorist attacks Detailed central and local planning in UK, escalating in 2007
Only treatment available for first wave of flu to be targeted antivirals, as vaccine expected to take 6 months
Planning for Influenza Pandemic
April 2009 Cases of swine flu in humans in Mexico, identified as H1N1, early cases suggest high mortality
Rapid spread to other countries and continents
June 2009 - WHO declares Influenza Pandemic
Vaccine available in 4 months
By November 2009 cases declining internationally
Morbidity and mortality much lower than anticipated, although pregnant women particularly affected
August 2010 - WHO declares pandemic over
Winter 2010/11 H1N1 now part of seasonal flu strains. Problematic locally, especially over Xmas 2010
2009 Swine Flu Pandemic
Virus emerged in humans following multiple reassortment events between swine viruses
Emerged in Mexico in mid February
Mid April the new virus was identified in California as an H1N1 virus of swine origin
By 21 May, 41 countries had reported 11,034 cases including 85 deaths
UK first imported cases were detected on 27 April and a wave of activity gradually took off peaking in mid/late July
2009 Swine Flu
Rates of infection were highest in children & young adults and lowest among the elderly
Elderly may have had some cross protective immunity from exposure in the 1950s to related influenza viruses
The pandemic vaccine was not available until October 2009
Globally 284,500 deaths
H1N1 virus remains one of the seasonal flu strains
2009 Swine Flu
Pandemic (H1N1) Influenza - 2009
Wirral PCT coordinated the response to Swine Flu
Anti-viral Collection Points (AVCP) established across Wirral
Staffed by Wirral PCT
Infection control training provided to staff working in AVCP
Infection control support to all Providers across Wirral
Late October 2009 – vaccine available for priority groups
Phase 2 of vaccine programme – December 2009 (children 6 months – 5 years)
2009 Swine Flu
Majority of hospitalisations and deaths were in people aged less than 65 years
Highest hospitalisation rate was consistently in children aged less than 5 years
2,831 people hospitalised in England
First reported UK death occurred on 14 June 2009
474 UK deaths were reported up to 15 April 2010◦ 359 in England◦ 69 in Scotland◦ 18 in Northern Ireland◦ 28 in Wales
2009 Swine Flu
Quiz
What can you remember about:◦Glenfield Hospital, Leicester ?◦Respirator fit testing ?◦Chinese star anise ?◦Rosie the Riveter ?
Wirral Community NHS Trust staff – flu vaccine available for all – see staffzone for further details
Staff working in Health & Social Care – discuss availability of vaccine with employer
In a clinical risk group – see your GP
Be a Flu Fighter!