Transcript Slide 1

OBJECTIVES
• Pandemic Influenza Then and Now
• Public Health Pandemic Influenza
Planning
– What to expect
– What not to expect
• Individual/Employee Pandemic Planning
WHAT IS PANDEMIC INFLUENZA?
• A global influenza outbreak
– Caused by a change in a flu virus
– Most severe occur with big changes in the virus
• Because it is a drastically changed virus, few or no people
would be immune
• Many people would get sick in every part of the world
• Asia is the source of many outbreaks because swine, birds and
humans live under the same roof, providing opportunity for viral
mixing
HOW DOES INFLUENZA VIRUS CHANGE?
• Antigenic Drift:
– Small changes in virus over time
– New strains appear and replace older strains
– May not be recognized by antibodies to older strains
• Antigenic Shift:
– Abrupt, major change (reassortment)
– Results in novel strain or new subtype
– Can cause pandemic influenza
PANDEMIC INFLUENZA CYCLE
• Recognized global outbreaks of influenza since the
1500’s
• Historical cycles of 10 to 40 years
• Rapid transmission worldwide.
• High attack rate for all age groups.
• High mortality rates, esp. for young adults.
1918: Spanish Flu
A(H1N1)
20-40 m deaths
675,000 US deaths
1957:AsianFlu
A(H2N2)
1-4 m deaths
70,000 US deaths
1968: Hong Kong Flu
A(H3N2)
1-4 m deaths
34,000 US deaths
Influenza Pandemics 20th Century
GLOBAL STATUS OF CURRENT PANDEMIC THREAT
• World Health Organization (WHO) defines 3 major periods (broken
into 6 phases) of increasing human infection with new flu virus:
– Interpandemic (no human infection)
– Pandemic Alert (limited human infection)
– Pandemic (widespread human infection)
• We are at Pandemic Alert
• Isolated human infections with a novel influenza strain [H5N1] with no
(or rare) person-to-person transmission.
2003
Country
2004
2005
2006
2007
2008
Total
cases
death
s
cases
death
s
cases
death
s
cases
death
s
cases
death
s
cases
death
s
cases
death
s
Azerbaijan
0
0
0
0
0
0
8
5
0
0
0
0
8
5
Cambodia
0
0
0
0
4
4
2
2
1
1
0
0
7
7
China
1
1
0
0
8
5
13
8
5
3
0
0
27
17
Djibouti
0
0
0
0
0
0
1
0
0
0
0
0
1
0
Egypt
0
0
0
0
0
0
18
10
25
9
0
0
43
19
Indonesia
0
0
0
0
20
13
55
45
42
37
9
8
126
103
Iraq
0
0
0
0
0
0
3
2
0
0
0
0
3
2
Lao People's Democratic
Republic
0
0
0
0
0
0
0
0
2
2
0
0
2
2
Myanmar
0
0
0
0
0
0
0
0
1
0
0
0
1
0
Nigeria
0
0
0
0
0
0
0
0
1
1
0
0
1
1
Pakistan
0
0
0
0
0
0
0
0
1
1
0
0
1
1
Thailand
0
0
17
12
5
2
3
3
0
0
0
0
25
17
Turkey
0
0
0
0
0
0
12
4
0
0
0
0
12
4
Viet Nam
3
3
29
20
61
19
0
0
8
5
1
1
102
48
Total
4
4
46
32
98
43
115
79
86
59
10
9
359
226
Source World Health Organization
WILL H5N1 BE THE NEXT PANDEMIC?
• Impossible to know if or when
• If not H5N1, then another will come
• The prudent time to plan is now
AVIAN FLU
• OCCURS
REGULARLY IN
AVIAN SPECIES
• SOMETIMES
SPREADS TO
OTHER SPECIES
PANDEMIC FLU
• OCCURS
PERIODICALLY IN
HUMANS
• CAN BE CAUSED BY
ANY STRAIN OF
INFLUENZA VIRUS
PLANNING ASSUMPTIONS: DISEASE TRANSMISSION
• No one immune to virus; 30% of population will become ill
• People may be contagious up to 24 hours before they know they are
sick
• People are most contagious the first 2 days of illness
– Sick children are more contagious than adults
• On average, each ill person can infect 2 or 3 others (if no precautions
are taken)
Medical Burden in Knox County
Based on 2006 Knox County population estimate of 399,254
Characteristic
Moderate*
Severe*
Illness
119,775 [30% of pop]
119,775 [30% of pop]
Outpatient care
59,890 [50% of ill]
59,890 [50% of ill]
Hospitalization
1,200 [1% of ill]
13,175 [11% of ill]
ICU Care
180 [15% of hosp]
1,975 [15% of hosp]
Mechanical Ventilation 90 [50% of ICU]
Deaths
(Case fatality rate)
240 [0.2% of ill]
990 [50% of ICU]
2,395 [2% of ill]
HEALTH AND HUMAN SERVICES PLANNING OBJECTIVES
• Primary objective:
– Minimize sickness and death
• Secondary objectives:
– Preserve functional society
– Minimize economic disruption
INFLUENZA CONTAINMENT STRATEGIES
• Routine Activities
– Surveillance
• 911 calls
• ER visits
• Sentinel physicians
– Public information and education
– Promote “respiratory hygiene” and hand washing
• Unique Activities
– Measures to increase social distancing
– Change how we perform our day-to-day business to protect
our staff and patients who still need our services
INFLUENZA CONTAINMENT
• Very early isolation and quarantine
• Reduce social contact
– Stay home if you are sick
– Canceling large gatherings, mass transit, schools
• Decision based on location of flu activity:
– Outbreak not local: gatherings >10,000 cancelled
– Outbreak in local/neighboring county: >100
• School closings determined by State Commissioner of
Health/Board of Education.
• Heavy reliance on personal measures
INFLUENZA CONTAIMENT, PERSONAL MEASURES
• Hand Hygiene
– Frequent washing
– 60%-95% alcohol-based
sanitizer
• Respiratory Hygiene
– Cover your cough
• Environmental cleaning
– 1:10 bleach solution
– EPA registered disinfectant
• Gloves & surgical masks for direct contact with ill person
• These apply at home and at work
Flu Vaccine
•
•
•
Production minimum 6
month process:(growing 93
million eggs)
HHS priority groups
– Military and vaccine
manufacturers
– Healthcare workers with
direct patient care
– Persons at highest risk
for complications
Two doses needed for
protection
Tamiflu
• Anti-viral agent
• Could be used to contain
first human outbreak
• Resistance described
• Should be used within 48 of
infection
• HHS priority groups: military
and hospitalized patients
• Tamiflu ≠ Preparedness
Guidance for Families
• Plan for childcare in the event schools
close
• Arrangements made for eldercare, pet
care
• Discuss/develop plan with employer
how you might work at home
Guidance for Families
• Personal protection:
– Hand hygiene and respiratory etiquette
– Surgical masks: proven effective for
droplet precautions
– Pneumococcal vaccination of those for whom it is
recommended
• Stockpiling: One to three week essential
water, food, supplies, medicines
RESOURCES
• PandemicFlu.gov
• CDC.gov/flu/avian
• www.nyhealth.gov
• Knoxcounty.org/health
• [email protected]