Influenza A(H1N1) (Swine Flu): A Global Outbreak

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Transcript Influenza A(H1N1) (Swine Flu): A Global Outbreak

Just-in-Time Lecture
Influenza A(H1N1) (Swine Flu) Pandemic
(Version 12, first JIT lecture issued April 26)
Tuesday, June 11, 2009 (11:30 PM EST)
Rashid A. Chotani, MD, MPH, DTM
Adjunct Assistant Professor
Uniformed Services University of the Health Sciences
(USUHS)
240-367-5370
[email protected]
CHOTANI © 2009.
Acknowledgement
The Author acknowledges the efforts, hard work and diligence for hosting this lecture, web-management
& translations and thanks the entire Supercourse Team, specially the following
Dr. Ronald E. LaPorte, University of Pittsburgh, USA
Dr. Eugene Shubnikov, Institute of Internal medicine, Novosibirsk, Russia
Dr. Faina Linkov, University of Pittsburgh, USA
Dr. Mita Lovalekar, University of Pittsburgh, USA
Dr. Nicolás Padilla Raygoza, Universidad de Guanajuato, México
Dr. Ali Ardalan, Tehran University of Medical Sciences, Iran
Dr. Mehrdad Mohajery, Tehran University of Medical Sciences, Iran
Dr. Seyed Amir Ebrahimzadeh, Tehran University of Medical Sciences, Iran
Dr. Nasrin Rahimian, Tehran University of Medical Sciences, Iran
Dr. Mohd Hasni , University of Kebangsaan, Malaysia
Dr. Kawkab Shishani, The Hashemite University, Jordan
Dr. Nesrine Ezzat Abdlkarim, Beirut Arab University, Lebanon
Dr. Khowlah Almohaini, University of Pittsburgh, USA
Dr. Duc Nguyen, University of Texas, USA
Dr. Elisaveta Jasna Stikova, University “Ss. Cyril and Methodius”, Skopje, Macedonia
Dr. Michèle Cazaubon, Secrétaire Gle de la Société Française d' Angéiologie, France
Dr. Yang Yingyun , Peking Union Medical College, China
Dr. Jesse Huang, Peking Union Medical College, China
Shimon Weitzman, Ben Gurion University of the Negev , Israel
Dr. Nurka Pranjic, Medical School University of Tuzla, Bosnia and Herzegovina
Dr. Shakir Jawad, Uniformed Services University of the Health Sciences, USA
Dr. Hiroya Goto, Ministry of Defense, Japan
Dr. Osamu Usami, National Cancer Institute, USA
Afham A. Chotani, USA
Truly a global effort
http://www.pitt.edu/~super1/
CHOTANI © 2009.
OUTLINE
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Influenza Virus
Definitions
Introduction
History in the US
Spread/Transmission
Timeline/Facts
Response
Status Update
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10.
Case-Definitions
Guidelines
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CHOTANI © 2009.
Mexico
US
Canada
European Union
Globally
Clinicians
Laboratory Workers
General Population
Treatment
Other Protective Measures
Summary
Timeline of Emergence
Lessons Learned from Past Pandemics
Conclusion & Recommendations
Virus
• RNA, enveloped
• Viral family: Orthomyxoviridae
• Size:
80-200nm or .08 – 0.12 μm
(micron) in diameter
• Three types
• A, B, C
• Surface antigens
• H (haemaglutinin)
• N (neuraminidase)
CHOTANI © 2009.
Credit: L. Stammard, 1995
Haemagglutinin subtype
H1
H2
H3
H4
H5
H6
H7
H8
H9
H10
H11
H12
H13
H14
H15
H16
Neuraminidase subtype
N1
N2
N3
N4
N5
N6
N7
N8
N9
Definitions
General
• Epidemic – a located cluster of cases
• Pandemic – worldwide epidemic
• Antigenic drift
• Changes in proteins by genetic point mutation & selection
• Ongoing and basis for change in vaccine each year
• Antigenic shift
• Changes in proteins through genetic reassortment
• Produces different viruses not covered by annual vaccine
CHOTANI © 2009.
Survival of Influenza Virus
Surfaces and Affect of Humidity & Temperature*
• Hard non-porous surfaces 24-48 hours
• Plastic, stainless steel
• Recoverable for > 24 hours
• Transferable to hands up to 24 hours
• Cloth, paper & tissue
• Recoverable for 8-12 hours
• Transferable to hands 15 minutes
• Viable on hands <5 minutes only at high viral titers
• Potential for indirect contact transmission
*Humidity 35-40%, Temperature 28C (82F)
CHOTANI © 2009.
Source: Bean B, et al. JID 1982;146:47-51
Influenza
The Normal Burden of Disease
• Seasonal Influenza
• Globally: 250,000 to 500,000 deaths per year
• In the US (per year)
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~35,000 deaths
>200,000 Hospitalizations
$37.5 billion in economic cost (influenza & pneumonia)
>$10 billion in lost productivity
• Pandemic Influenza
• An ever present threat
CHOTANI © 2009.
Swine Influenza A(H1N1)
Introduction
• Swine Influenza (swine flu) is a respiratory
disease of pigs caused by type A influenza
that regularly cause outbreaks of influenza
among pigs
• Most commonly, human cases of swine flu
happen in people who are around pigs
• Swine flu viruses do not normally infect
humans, however, human infections with
swine flu do occur, and cases of human-tohuman spread of swine flu viruses have
been documented
CHOTANI © 2009.
Swine Influenza A(H1N1)
History in US
•
A swine flu outbreak in Fort Dix, New Jersey,
USA occurred in 1976 that caused more
than 200 cases with serious illness in several
people and one death
•
•
More than 40 million people were vaccinated
However, the program was stopped short
after over 500 cases of Guillain-Barre
syndrome, a severe paralyzing nerve disease,
were reported
• 30 people died as a direct result of the
vaccination
•
In September 1988, a previously healthy 32year-old pregnant woman in Wisconsin was
hospitalized for pneumonia after being
infected with swine flu and died 8 days later.
•
From December 2005 through February
2009, a total of 12 human infections with
swine influenza were reported from 10 states
in the United States
CHOTANI © 2009.
Swine Influenza A(H1N1)
Transmission to Humans
• Through contact with infected pigs or
environments contaminated with
swine flu viruses
• Through contact with a person with
swine flu
• Human-to-human spread of swine flu
has been documented also and is
thought to occur in the same way as
seasonal flu, through coughing or
sneezing of infected people
CHOTANI © 2009.
Swine Influenza A(H1N1)
Transmission Through Species
Human Virus
Avian Virus
Avian/Human
Reassorted Virus
Swine Virus
Reassortment in Pigs
CHOTANI © 2009.
Swine Influenza A(H1N1) March 2009
Timeline
•
In March and early April 2009, Mexico experienced
outbreaks of respiratory illness and increased
reports of patients with influenza-like illness (ILI) in
several areas of the country
•
April 12, the General Directorate of Epidemiology
(DGE) reported an outbreak of ILI in a small
community in the state of Veracruz to the Pan
American Health Organization (PAHO) in
accordance with International Health Regulations
•
April 17, a case of atypical pneumonia in Oaxaca
State prompted enhanced surveillance throughout
Mexico
•
April 23, several cases of severe respiratory illness
laboratory confirmed as influenza A(H1N1) virus
infection were communicated to the PAHO
•
Sequence analysis revealed that the patients were
infected with the same strain detected in 2 children
residing in California
•
CHOTANI © 2009.
Samples from the Mexico outbreak match swine
influenza isolates from patients in the United States
Source: CDC
Swine Influenza A(H1N1) March 2009
Facts
•
Virus described as a new subtype of
A/H1N1 not previously detected in
swine or humans
•
CDC determines that this virus is
contagious and is spreading from
human to human
•
The virus contains gene segments from
4 different influenza types:
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•
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•
CHOTANI © 2009.
North American swine
North American avian
North American human and
Eurasian swine
Swine Influenza A(H1N1)
US Response
•
The Strategic National Stockpile (SNS) is
releasing one-quarter of its
•
•
•
Anti-viral drugs
Personal protective equipment and
Reparatory protection devices
•
President Obama today asked Congress for
an additional $1.5 billion to fight the swine flu
•
On April 27, 2009, the CDC issued a travel
advisory that recommends against all nonessential travel to Mexico
CHOTANI © 2009.
Source: CDC
Swine Influenza A(H1N1)
Global Response
•
The WHO raises the alert level to Phase 6
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•
CHOTANI © 2009.
WHO’s alert system was revised after Avian influenza began to spread in 2004 – Alert Level raised to Phase 3
In Late April 2009 WHO announced the emergence of a novel influenza A virus
April 27, 2009: Alert Level raised to Phase 4
April 29, 2009: Alert Level raised to Phase 5
June 11, 2008: Alert Level raised to Phase 6
Source: WHO
Swine Influenza A(H1N1) May 25, 2009
Status Update
•
MEXICO: March 01-June 09, a total of
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•
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•
UNITED STATES: March 28-June 09, a total
of
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•
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•
•
6,241 Laboratory confirmed cases
108 deaths reported
All 32 States
13,217 Laboratory confirmed cases,
27 deaths
All Sates plus District of Columbia and Puerto
Rico
Vast majority of cases mild
CANADA: As of June 10, a total of
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•
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CHOTANI © 2009.
2,978 Laboratory confirmed cases,
4 deaths
12 of 13 States
533 new Laboratory confirmed cases June 8
Vast majority of cases mild
Source: Secretaria de Salud, Mexico, CDC, Public Health Agency of Canada, European CDC, WHO
Swine Influenza A(H1N1) May 25, 2009
Status Update
•
EUROPEAN UNION & EFTA COUNTRIES:
April 27- May 25, a total of
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•
•
•
•
•
•
1,565 Laboratory confirmed cases
no deaths
26 countries
126 confirmed cases reported on June 09
567 in-country transmissions
Vast majority of cases reported between 20-49
years of age
GLOBALLY: March 1-May 25, a total of
•
•
CHOTANI © 2009.
27,737 Laboratory confirmed cases, from 74
countries
144 Deaths among laboratory confirmed cases
from 7 countries
• Mexico:
108 deaths
• US:
27 deaths
• Canada:
04 death
• Chile:
02 deaths
• Costa Rica:
01 death
• Columbia:
01 death
• Dominican Rep.: 01 death
Source: Secretaria de Salud, Mexico, CDC, Public Health Agency of Canada, European CDC, WHO
Swine Influenza A(H1N1)
Mexico Epidemic Curve Confirmed, by Day
As of June 09, 2009
Total Number of Confirmed Cases = 6,241*
Suspension of Non-essential Activities
School Closure
400
No. of Confirmed Cases
400
School Open
385
350
309
290
300
270
262
250
224
217
221
214
199 201
200
186
176
168
158
148
150
128
127
Epidemiological Alert
122
100
126
112
92
90
76
50
77
31
14
8 4 8
6 7 7 3
3 1 3 4
1 0 0 0 1 1 2 1 1 1 1 2 2 4 3 2 0 2 3 5 3
2
15
14
10 10
85
76
22
71
75
69
65
61
59 59
52
50
41
3637 31 33
29
25
20
8
16
4
0
Day
*NOTE: 54 confirmed cases not included
CHOTANI © 2009.
Source: Secretaria de Salud, Mexico
Swine Influenza A(H1N1)
Mexico Confirmed Case Distribution, by Age
As of June 09, 2009
No. Confirmed Cases
Total Number of Confirmed Cases = 6,241*
2000
1800
1600
1400
1200
1000
800
600
400
200
0
1776
1720
1191
638
476
273
127
0-9
10-19
20-29
30-39
40-49
50-59
60+
40
NA
Age Group
*NOTE: 54 confirmed cases not included
CHOTANI © 2009.
Source: Secretaria de Salud, Mexico
Swine Influenza A(H1N1)
Mexico Confirmed Cases & Death, by Age Groups
Male:
48.1%
Fem ale:
51.9%
As of June 09, 2009
Total Number of Confirmed Cases = 6,241*
Deaths = 108
Deaths
16
%
100
71.3% Deaths
No. of Deaths
80
12
70
10
60
8
50
40
6
30
4
12
2
2.8
3.7
6.5
12
9.3
20
13.9
7.4
3.7
8.3
8.3
5.6
1.9
0.9
0
0.9
1.9
Case-Fatality (%)
90
14
10
0
>75
70-74
65-69
60-64
55-59
50-54
45-49
40-44
35-39
30-34
25-29
20-24
15-19
10-14
5-9
1-4
<1
Age Group
*NOTE: 43 confirmed cases not included
CHOTANI © 2009.
Source: Secretaria de Salud, Mexico
Swine Influenza A(H1N1)
Mexico Death, by Occupation
House Bound
22
Independent Worker
15
Private Sector Worker
13
Student
8
Tradesmen
5
Minor
5
N=80
Professional
4
Pubic Sector Worker
3
Unemployed
3
Retired
2
0
5
10
15
Deaths
CHOTANI © 2009.
20
25
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No. of Confirmed Cases
Swine Influenza A(H1N1)
US Confirmed Cases & Deaths, by State
As of June 11, 2009 (12:30 PM ET)
Total Number of Confirmed Cases = 13,217; 27 Death; 50 States + District of Columbia + Puetro Rico
2500
2217
2000
5
1500
CHOTANI © 2009.
547
500
94
75
3 9
142
247
115
33
16
1670
3
1357
973
8
1000
4
858
1
787
395
173
92 92 96134
298
89
17
128 148
108
60
82 40 46 15
64
1
30 23 35
1
1
461
2
93167
104
18 60 10
577
299
9
55
1
24 6
25 1
0
US States
Source: CDC
Swine Influenza A(H1N1)
MMRW Report, April 28
• MMWR, April 28, 2009 / 58(Dispatch);1-3
• 47 patients reported to CDC with known ages (out of 64)
the median age was 16 years (range: 3-81 years)
• 38 (81%) were aged <18 years
• 51% of cases were in males
• Of the 25 cases with known dates of illness onset, onset
ranged from March 28 to April 25
• Five patients hospitalized
• Of 14 patients with known travel histories
• 3 had traveled to Mexico
• 40 of 47 patients (85%) had not been linked to travel or to
another confirmed case
CHOTANI © 2009.
Source: CDC. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm58d0428a2.htm
Swine Influenza A(H1N1)
MMRW Report, April 30
MMWR, April 30, 2009 / 58(Dispatch);1-3
•
NYC school (high school A)
•
•
•
•
•
•
•
•
•
2,686 students and 228 staff members
April 23-24, 222 students visited the school nursing office and left school because of
illness
DOHMH collect nasopharyngeal swabs from any symptomatic students
April 24 (Friday), DOHMH collected nasopharyngeal swabs from five newly symptomatic
students identified by the school nurse and four newly symptomatic students identified
at a nearby physician's office
April 27, School closed
DOHMH also provided nasopharyngeal test kits to selected physicians' offices in the
vicinity of high school A
April 26, 7 of 9 specimens collected on April 24 were positive for the new strain of
influenza
April 26-28, 37 (88%) of 42 specimens collected tested positive, bringing the total
number of confirmed cases to 44
April 27 DOHMH conducted telephone interviews with the 44 patients
•
•
•
•
•
CHOTANI © 2009.
Median age was 15 years (range: 14-21 years)
All were students, with the exception of one student teacher aged 21 years
Thirty-one (70%) of the 44 were female
Thirty (68%) were non-Hispanic white; seven (16%) were Hispanic; two (5%) were non-Hispanic
black; and five (11%) were other races
Four patients reported travel outside NYC within the United States in the week before symptom
onset, and an additional patient traveled to Aruba in the 7 days before symptom onset. None of
the 44 patients reported recent travel to California, Texas, or Mexico
Source: CDC. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm58d0428a2.htm
Swine Influenza A(H1N1)
MMRW Report, April 30
MMWR, April 30, 2009 / 58(Dispatch);1-3
•
Illness onset dates ranged from April 20 to
April 24
•
•
•
•
•
CHOTANI © 2009.
10 (23%) of the patients had illness onset on
April 22, and 28 (64%) had illness onset on April
23 (Figure).
Among 35 patients who reported a maximum
temperature, the mean was 102.2°F (39.0°C)
(range: 99.0-104.0°F [37.2--40.0°C])
In total, 42 (95%) patients reported subjective
fever plus cough and/or sore throat, meeting the
CDC definition for influenza-like illness (ILI)
At the time of interview on April 27, 37 patients
(84%) reported that their symptoms were stable
or improving, three (7%) reported worsening
symptoms (two of whom later reported
improvement), and four (9%) reported complete
resolution of symptoms
Only one reported having been hospitalized for
syncope and released after overnight
observation
Symptoms
Number
(n=44)
%
Cough
43
98%
Fever
42
96%
Fatigue
39
89%
Headache
36
82%
Sore throat
36
82%
Runny nose
36
82%
Chills
35
80%
Muscle aches
35
80%
Nausea
24
55%
Stomach ache
22
50%
Diarrhea
21
48%
Shortness of breath
21
48%
Joint pain
20
46%
Source: CDC. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm58d0428a2.htm
Swine Influenza A(H1N1)
Canada Confirmed Cases & Death, by Province or Territory
2
1800
1562
1200
1
611
600
1
151
195
221
56
2
78
3
1
2
96
0
Nunavut
Northwest
Territories
Yukon
Newfoundland
Prince Eward
Island
Nova Scotia
New
Brunswick
Quebec
Ontario
Manitoba
Saskatchewan
Alberta
British
Columbia
No. of Confirmed Cases & Deaths
As of June 11, 2009 1500 (EDT)
Total Number of Confirmed Cases 2,978 = ; Death = 4; 12 of 13 Provinces
Province or Territory
CHOTANI © 2009.
Source: Public Health Agency of Canada
Swine Influenza A(H1N1)
EU & EFTA Confirmed Cases & In-Country Transmission
April 27 - June 11, 2009 (1700 CEST)
Total Number of Confirmed Cases = 1,565; 0 Death; 26 Countries;
567 In-Country Transmissions
In-Country Transmission
900
822
600
380
357
300
21 7
56
4
3
12 1
4 1
23
4
13
1
7
1 2
19 18
4
11 6 3
1
United Kingdom
Switzerland
Sweden
Spain
Slovakia
Romania
Portugal
Poland
Norway
Netherlands
Luxembourg
Italy
Ireland
Iceland
Hungry
Greece
Denmark
8
Germany
Czech Rep.
4 2 4
France
10 2
Finland
4
Estonia
1
Cyprus
Belgium
2
Bulgaria
0
7 1 14 4
127
90
71
Austria
No. of Confirmed Cases & In-Country
Transmission
Confirmed cases
Country
CHOTANI © 2009.
Source: ECDC
Swine Influenza A(H1N1)
EU & EFTA Countries Epidemic Curve Confirmed, by Day
April 27 – June 11, 2009 (1700 CEST)
N=1,565
Number of Confirmed Cases
Days
CHOTANI © 2009.
Source: ECDC
Swine Influenza A(H1N1)
EU & EFTA Countries Confirmed Case Distribution, by Age
27 April to 8 May 2009
N=46
25
23
Confirmed Cases
20
15
10
7
6
5
5
3
2
0
0-9
10-19
20-29
30-39
40-49
50-59
Age Group (Years)
CHOTANI © 2009.
Source: ECDC
Laboratory-Confirmed Cases of New Influenza
A(H1N1) by Countries, June 11, 2009
28,774 Cases & 144 Deaths
74 Countries
27
108
4
2
1
1
1
Chinese Taipei has reported 36 confirmed cases of influenza A (H1N1) with 0 deaths. Cases from Chinese Taipei are included in the
cumulative totals provided in the table above.
Cumulative and new figures are subject to revision
CHOTANI © 2009.
Source: WHO
Global Distribution of Reported Cumulative Laboratory Confirmed
Cases of Swine Influenza A(H1N1) by Countries, June 11, 2009
(14:00 GMT)
CHOTANI © 2009.
Source: WHO
Swine Influenza A(H1N1)
US Case Definitions
•
A confirmed case of swine influenza A (H1N1) virus infection is defined as a
person with an acute febrile respiratory illness with laboratory confirmed swine
influenza A (H1N1) virus infection at CDC by one or more of the following tests:
•
•
•
A probable case of swine influenza A (H1N1) virus infection is defined as a
person with an acute febrile respiratory illness who is:
•
•
•
real-time RT-PCR
viral culture
positive for influenza A, but negative for H1 and H3 by influenza RT-PCR, or
positive for influenza A by an influenza rapid test or an influenza
immunofluorescence assay (IFA) plus meets criteria for a suspected case
A suspected case of swine influenza A (H1N1) virus infection is defined as a
person with acute febrile respiratory illness with onset
•
•
•
CHOTANI © 2009.
within 7 days of close contact with a person who is a confirmed case of swine
influenza A (H1N1) virus infection, or
within 7 days of travel to community either within the United States or internationally
where there are one or more confirmed swine influenza A(H1N1) cases, or
resides in a community where there are one or more confirmed swine influenza
cases.
Source: CDC
Swine Influenza A(H1N1)
US Case Definitions
• Infectious period for a confirmed case of swine influenza A(H1N1)
virus infection is defined as 1 day prior to the case’s illness onset to 7
days after onset
• Close contact is defined as: within about 6 feet of an ill person who is
a confirmed or suspected case of swine influenza A(H1N1) virus
infection during the case’s infectious period
• Acute respiratory illness is defined as recent onset of at least two of
the following: rhinorrhea or nasal congestion, sore throat, cough (with
or without fever or feverishness)
• High-risk groups: A person who is at high-risk for complications of
swine influenza A(H1N1) virus infection is defined as the same for
seasonal influenza (see Reference)
CHOTANI © 2009.
Source: CDC
Swine Influenza A(H1N1)
Guidelines for Clinicians
• Clinicians should consider the possibility of swine
influenza virus infections in patients presenting with
febrile respiratory illness who
• live in areas where human cases of swine influenza A(H1N1)
have been identified or
• have traveled to an area where human cases of swine influenza
A(H1N1) has been identified or
• have been in contact with ill persons from these areas in the 7
days prior to their illness onset
• If swine flu is suspected, clinicians should obtain a
respiratory swab for swine influenza testing and place it
in a refrigerator (not a freezer)
• once collected, the clinician should contact their state or local
health department to facilitate transport and timely diagnosis at
a state public health laboratory
CHOTANI © 2009.
Source: CDC
Swine Influenza A(H1N1)
Guidelines for Clinicians
• Signs and Symptoms
• Influenza-like-illness (ILI)
• Fever, cough, sore throat, runny nose, headache, muscle aches. In
some cases vomiting and diarrhea. (These cases had illness onset
during late March to mid-April 2009)
• Cases of severe respiratory disease, requiring hospitalization
including fatal outcomes, have been reported in Mexico
• The potential for exacerbation of underlying chronic medical
conditions or invasive bacterial infection with swine influenza virus
infection should be considered
• Non-hospitalized ill persons who are a confirmed or
suspected case of swine influenza A (H1N1) virus
infection are recommended to stay at home (voluntary
isolation) for at least the first 7 days after illness onset
except to seek medical care
CHOTANI © 2009.
Source: CDC
Swine Influenza A(H1N1)
Guidelines for Clinicians
FDA Issues Authorizations for Emergency Use (EUAs) of Antivirals
•
On April 27, 2009, the U.S. Food and Drug Administration (FDA) issued
EUAs in response to requests by the Centers for Disease Control and
Prevention (CDC) for the swine flu outbreak
•
One of the reasons the EUAs could be issued was because the U.S.
Department of Health and Human Services (HHS) declared a public health
emergency on April 26, 2009
•
The swine influenza EUAs aid in the current response:
CHOTANI © 2009.
•
Tamiflu: Allow for Tamiflu to be used to treat and prevent influenza in children
under 1 year of age, and to provide alternate dosing recommendations for
children older than 1 year. Tamiflu is currently approved by the FDA for the
treatment and prevention of influenza in patients 1 year and older.
•
Tamiflu and Relenza: Allow for both antivirals to be distributed to large segments
of the population without complying with federal label requirements that would
otherwise apply to dispensed drugs and to be accompanied by written
information about the emergency use of the medicines.
Source: FDA
Swine Influenza A(H1N1)
Biosafety Guidelines for Laboratory Workers
•
Diagnostic work on clinical samples from patients who are suspected
cases of swine influenza A (H1N1) virus infection should be conducted in
a BSL-2 laboratory
•
All sample manipulations should be done inside a biosafety cabinet (BSC)
•
Viral isolation on clinical specimens from patients who are suspected
cases of swine influenza A (H1N1) virus infection should be performed in
a BSL-2 laboratory with BSL-3 practices (enhanced BSL-2 conditions)
•
Additional precautions include:
•
•
•
•
•
•
•
recommended personal protective equipment (based on site specific risk
assessment)
respiratory protection - fit-tested N95 respirator or higher level of protection
shoe covers
closed-front gown
double gloves
eye protection (goggles or face shields)
Waste
•
CHOTANI © 2009.
all waste disposal procedures should be followed as outlined
in your facility standard laboratory operating procedures
Source: CDC
Swine Influenza A(H1N1)
Biosafety Guidelines for Laboratory Workers
• Appropriate disinfectants
• 70 per cent ethanol
• 5 per cent Lysol
• 10 per cent bleach
• All personnel should self monitor for fever and any
symptoms. Symptoms of swine influenza infection
include diarrhea, headache, runny nose, and muscle
aches
• Any illness should be reported to your supervisor
immediately
• For personnel who had unprotected exposure or a
known breach in personal protective equipment to
clinical material or live virus from a confirmed case of
swine influenza A (H1N1), antiviral chemoprophylaxis
with zanamivir or oseltamivir for 7 days after exposure
can be considered
CHOTANI © 2009.
Source: CDC
Swine Influenza A(H1N1)
Biosafety Guidelines for Laboratory Workers
FDA Issues Authorizations for Emergency Use (EUAs) of Diagnostic
Tests
•
On April 27, 2009, the U.S. Food and Drug Administration (FDA) issued
EUAs in response to requests by the Centers for Disease Control and
Prevention (CDC) for the swine flu outbreak
•
One of the reasons the EUAs could be issued was because the U.S.
Department of Health and Human Services (HHS) declared a public health
emergency on April 26, 2009
•
The swine influenza EUAs aid in the current response:
•
CHOTANI © 2009.
Diagnostic Test: Allow CDC to distribute the rRT-PCR Swine Flu Panel
diagnostic test to public health and other qualified laboratories that have the
equipment and personnel to perform and interpret the results.
Source: CDC
Swine Influenza A(H1N1)
Guidelines for General Population
• Covering nose and mouth with a
tissue when coughing or sneezing
• Dispose the tissue in the trash after
use.
• Handwashing with soap and water
• Especially after coughing or sneezing.
• Cleaning hands with alcohol-based
hand cleaners
• Avoiding close contact with sick
people
• Avoiding touching eyes, nose or
mouth with unwashed hands
• If sick with influenza, staying home
from work or school and limit
contact with others to keep from
infecting them
CHOTANI © 2009.
Swine Influenza A(H1N1)
Treatment
• No vaccine available
• Antivirals for the treatment and/or prevention of infection:
• Oseltamivir (Tamiflu) or
• Zanamivir (Relenza)
• Use of anti-virals can make illness milder and recovery faster
• They may also prevent serious flu complications
• For treatment, antiviral drugs work best if started soon after getting
sick (within 2 days of symptoms)
• Warning! Do NOT give aspirin (acetylsalicylic acid) or aspirincontaining products (e.g. bismuth subsalicylate – Pepto Bismol) to
children or teenagers (up to 18 years old) who are confirmed or
suspected ill case of swine influenza A (H1N1) virus infection; this
can cause a rare but serious illness called Reye’s syndrome. For
relief of fever, other anti-pyretic medications are recommended such
as acetaminophen or non steroidal anti-inflammatory drugs.
CHOTANI © 2009.
Source: CDC
Swine Influenza A(H1N1)
Treatment
Oseltamivir (Tamiflu)
Treatment
Prophylaxis
Zanamivir (Relenza)
Treatment
Prophylaxis
Adults
75 mg capsule twice
per day for 5 days
75 mg capsule once
per day
Two 5 mg inhalations
(10 mg total) twice per
day
Two 5 mg inhalations
(10 mg total) once per
day
Children
15 kg or less: 60 mg
per day divided into 2
doses
30 mg once per day
Two 5 mg inhalations
(10 mg total) twice per
day (age, 7 years or
older)
Two 5 mg inhalations
(10 mg total) once per
day (age, 5 years or
older)
15–23 kg: 90 mg per
day divided into 2
doses
45 mg once per day
24–40 kg: 120 mg per
day divided into 2
doses
60 mg once per day
>40 kg: 150 mg per
day divided into 2
doses
75 mg once per day
Dosing recommendations for antiviral treatment of children younger than 1 year using oseltamivir. Recommended treatment
dose for 5 days. <3 months: 12 mg twice daily; 3-5 months: 20 mg twice daily; 6-11 months: 25 mg twice daily
Dosing recommendations for antiviral chemoprophylaxis of children younger than 1 year using oseltamivir. Recommended
prophylaxis dose for 10 days. <3 months: Not recommended unless situation judged critical due to limited data on use in this
age group; 3-5 months: 20 mg once daily; 6-11 months: 25 mg once daily
CHOTANI © 2009.
Source: CDC
Swine Influenza A(H1N1)
Other Protective Measures
Defining Quarantine vs. Isolation vs. Social-Distancing
• Isolation: Refers only to the sequestration of symptomatic
patents either in the home or hospital so that they will not infect
others
• Quarantine: Defined as the separation from circulation in the
community of asymptomatic persons that may have been
exposed to infection
• Social-Distancing: Has been used to refer to a range of nonquarantine measures that might serve to reduce contact between
persons, such as, closing of schools or prohibiting large
gatherings
CHOTANI © 2009.
Source: CDC
Swine Influenza A(H1N1)
Other Protective Measures
Personnel Engaged in Aerosol Generating Activities
• CDC Interim recommendations:
• Personnel engaged in aerosol generating activities (e.g., collection of
clinical specimens, endotracheal intubation, nebulizer treatment,
bronchoscopy, and resuscitation involving emergency intubation or
cardiac pulmonary resuscitation) for suspected or confirmed swine
influenza A (H1N1) cases should wear a fit-tested disposable N95
respirator
• Pending clarification of transmission patterns for this virus, personnel
providing direct patient care for suspected or confirmed swine influenza
A (H1N1) cases should wear a fit-tested disposable N95 respirator when
entering the patient room
• Respirator use should be in the context of a complete respiratory
protection program in accordance with Occupational Safety and Health
Administration (OSHA) regulations.
CHOTANI © 2009.
Source: CDC
Swine Influenza A(H1N1)
Other Protective Measures
Infection Control of Ill Persons in a Healthcare Setting
• Patients with suspected or confirmed case-status should be placed
in a single-patient room with the door kept closed. If available, an
airborne infection isolation room (AIIR) with negative pressure air
handling with 6 to 12 air changes per hour can be used. Air can be
exhausted directly outside or be recirculated after filtration by a high
efficiency particulate air (HEPA) filter. For suctioning, bronchoscopy,
or intubation, use a procedure room with negative pressure air
handling.
• The ill person should wear a surgical mask when outside of the
patient room, and should be encouraged to wash hands frequently
and follow respiratory hygiene practices. Cups and other utensils
used by the ill person should be washed with soap and water before
use by other persons. Routine cleaning and disinfection strategies
used during influenza seasons can be applied to the environmental
management of swine influenza.
CHOTANI © 2009.
Source: CDC
Swine Influenza A(H1N1)
Other Protective Measures
Infection Control of Ill Persons in a Healthcare Setting
• Standard, Droplet and Contact precautions should be used for all
patient care activities, and maintained for 7 days after illness onset
or until symptoms have resolved. Maintain adherence to hand
hygiene by washing with soap and water or using hand sanitizer
immediately after removing gloves and other equipment and after
any contact with respiratory secretions.
• Personnel providing care to or collecting clinical specimens from
suspected or confirmed cases should wear disposable non-sterile
gloves, gowns, and eye protection (e.g., goggles) to prevent
conjunctival exposure.
CHOTANI © 2009.
Source: CDC
Types of Protective Masks
•
Surgical masks
•
•
High-filtration respiratory mask
•
•
•
•
CHOTANI © 2009.
Easily available and commonly used for routine surgical and examination
procedures
Special microstructure filter disc to flush out particles bigger than 0.3 micron.
These masks are further classified:
• oil proof
• oil resistant
• not resistant to oil
The more a mask is resistant to oil, the better it is
The masks have numbers beside them that indicate their filtration efficiency.
For example, a N95 mask has 95% efficiency in filtering out particles greater
than 0.3 micron under normal rate of respiration.
The next generation of masks use Nano-technologywhich are capable of
blocking particles as small as 0.027 micron.
Summary
•
WHO raised the alert level to Phase 6 on June 11, 2009
•
•
There is a disparity between the % case-fatality-rate between Mexico (1.73%), USA
(0.20%) and Canada (0.13%)
The overall global case-fatality (28,774 cases and 144 deaths) is 0.50%
•
~ 1,500 cases worldwide (reported) needed hospitalization
•
•
Majority in Mexico
Epidemiological Data
•
•
•
•
US
Median Age 16 years (range: 1-81 years)
Over 80% of the cases in <18 years
60% female; 40% Male
•
•
•
•
•
Mexico
Majority of the cases reported in health young adults
71.3% of the deaths were reported in healthy young adults, 20-54 years
Individuals 60+ seem to be protected as the number of cases and have a lower case-fatality
compared to the rest of the population
52% female; 48% Male
•
•
•
EU
Majority of the cases reported in health young adults (20-29 years).
In-country transmission (36%) has been documented
•
No vaccine is available
•
Anti-virals available
CHOTANI © 2009.
Timeline of Emergence
Influenza A Viruses in Humans
Reassorted Influenza
virus (Swine Flu)
1976 Swine
Flu Outbreak,
Ft. Dix
H1
Avian
Influenza
H9 H7
H5 H5
H1
H3
H2
H1
1918
1957
Spanish
Influenza
H1N1
Asian
Influenza
H2N2
CHOTANI © 2009.
1968
1977
Hong
Russian
Kong
Influenza
Influenza
H3N2
1997
2003
1998/9
2009
Lessons Learned form
Past Pandemics
•
First outbreaks March 1918 in Europe, USA
•
•
•
•
•
Highly contagious, but not deadly
Virus traveled between Europe/USA on troop
ships
Land, sea travel to Africa, Asia
Warning signal was missed
August, 1918 simultaneous explosive
outbreaks in in France, Sierra Leone, USA
•
•
10-fold increase in death rate
Highest death rate ages 15-35 years
•
•
•
•
•
Deaths from primary viral pneumonia, secondary
bacterial pneumonia
Deaths within 48 hours of illness
Coincident severe disease in pigs
20-40 million killed in less than 1 year
•
•
Cytokine Storm?
World War I –8.3 million military deaths over 4
years
25-35% of the world infected
CHOTANI © 2009.
Lessons Learned form
Past Pandemics
•
Pandemics are unpredictable
•
•
•
•
Mortality, severity of illness, pattern of spread
A sudden, sharp increase in the need for medical care
will always occur
Capacity to cause severe disease in nontraditional
groups is a major determinant of pandemic impact
Epidemiology reveals waves of infection
•
•
Ages/areas not initially infected likely vulnerable in future
waves
Subsequent waves may be more severe
•
•
•
1918- virus mutated into more virulent form
1957 schoolchildren spread initial wave, elderly died in
second wave
Public health interventions delay, but do not stop
pandemic spread
•
Quarantine, travel restriction show little effect
•
•
•
•
Temporary banning of public gatherings, closing schools
potentially effective in case of severe disease and high
mortality
Delaying spread is desirable
•
CHOTANI © 2009.
Does not change population susceptibility
Delay spread in Australia— later milder strain causes
infection there
Fewer people ill at one time improve capacity to cope with
sharp increase in need for medical care
Conclusion/Recommendations
1. Past experience with pandemics have taught us that the second wave
is worse than the first causing more deaths due to:
•
•
•
•
•
CHOTANI © 2009.
Primary viral pneumonia, Acute Respiratory Distress Syndrome (ARDS),
& Secondary bacterial infections, particularly pneumonia
Fortunately compared to the past now we have anti-virals and antibiotics
(to treat secondary bacterial infections)
Though difficult, there is likelihood that there will be a vaccine for this
strain by the emergence of the second wave
In the US each year ~35,000 deaths are attributed to influenza resulting in
>200,000 hospitalizations, costing $37.5 billion in economic cost
(influenza & pneumonia) and >$10 billion in lost productivity
Based upon past experience and the way the current H1N1 pandemic is
acting (current wave is contagious, spreading rapidly and in
Mexico/Canada based upon preliminary data affecting the healthy), there
is a likelihood that come fall there might be a second wave which could be
more virulent
Conclusion/Recommendations
2.
At present most of the deaths due to H1N1 strain has been reported
from Mexico.
•
•
•
•
•
3.
The disease, though spreading rapidly across the globe, is of a mild form
(exception Mexico)
Most people do not have immunity to this virus and, as it continues to
spread. More cases, more hospitalizations and some more deaths are
expected in the coming days and weeks
Disease seems to be affecting the healthy strata of the population based
upon epidemiological data from Mexico and EU
60 years and above age group seems to show some protection against
this strain suggesting past exposure and some immunity
Of concern is the disease spread in Australia
Each locality/jurisdiction needs to
•
•
•
•
CHOTANI © 2009.
Have enhanced disease and virological surveillance capabilities
Develop a plan to house large number of severely sick and provide care
if needed to deal with mildly sick at home (voluntary quarantine)
Healthcare facilities/hospitals need to focus on increasing surge capacity
and stringent infection prevention/control
General population needs to follow basic precautions
Conclusion/Recommendations
4.
In the Northern Hemisphere influenza viral transmission traditionally
stops by the beginning of May but in pandemic years (1957) sporadic
outbreaks occurred during summer among young adults
•
Likelihood that
•
•
•
5.
This wave will fade in North America by the end of June or will cause disease
in a few cases (influenza virus cannot survive high humidity or temperature)
Will reappear in autumn in North America with the likelihood of being a highly
pathogenic second wave
Will continue to circulate and cause disease in the Southern Hemisphere
Border Closure and Travel Restrictions:
•
The disease has already crossed all borders and continents, thus, border
closure or travel restrictions will not change the course of the spread of
disease
•
•
•
•
CHOTANI © 2009.
Most recently, the 2003 experience with SARS demonstrated the
ineffectiveness of such measures
In China, 14 million people were screened for fever at the airport, train
stations, and roadside checkpoints, but only 12 were found to have probable
SARS
Singapore reported that after screening nearly 500,000 air passengers, none
were found to have SARS
Passive surveillance methods (in which symptomatic individuals report illness)
can be important tools
Conclusion/Recommendations
6.
School Closures:
•
•
•
•
Preemptive school closures will merely delay the spread of disease
Once schools reopen (as they cannot be closed indefinitely), the disease
will be transmitted and spread
Furthermore, this would put unbearable pressure on single-working
parents and would be devastating to the economy (as children cannot be
left alone)
Closure after identification of a large cluster would be appropriate as
absenteeism rate among students and teachers would be high enough to
justify this action
7.
High priority should be given to develop and include the present
“North American” (swine) influenza A(H1N1) virus in next years
vaccine. A critical look at manufacturing capacity is called for
8.
It is imperative to appreciate that “times-have-changed”
•
CHOTANI © 2009.
Though this strain has spread very quickly across the globe and seems to
be highly infectious, today we are much better prepared than 1918. There
is better surveillance, communication, understanding of infection control,
anti-virals, antibiotics and advancement in science and resources to
produce an affective vaccine