Transcript in the Hospitals - (Swine) Influenza A (H1N1) Pandemic

Hospital Preparedness
and H1N1 2009 influenza
Khachornsakdi Silpapojakul MD
Prince of Songkla University
Hat yai, Songkla, Thailand
1
What ???
2
Swine influenza
Influenza as a disease of pigs was first
recognized during the Spanish influenza
pandemic of 1918–1919. Veterinarian J.
S. Koen was the first to describe the
illness,observing frequent outbreaks of
influenza in families followed
immediately by illness in their swine
herds,and vice versa.
3
Why important ?????
4
5
Country
Cases Deaths
MEXICO
4174
80
U.S.A
6552
9
CANADA
805
JAPAN
345
SPAIN
133
UK
122
PANAMA
Total
76
12515
1
0
0
0
0
91 (0.7%)
6
Pandemics?
the three important criteria for a new
pandemic influenza virus—ie, the ability to
replicate in human beings and the absence of
antibodies to the virus in the human
population at large. The third criterium is the
potential to rapidly spread from man to man.
7
Neuraminidase
Hemagglutinin
M2 ion channel
Drugs 2001;61:263-83
8
H5N1 Avian influenza
9
Human influenza A receptor = SAα2,6-linked
Avian influenza A receptor = SAα2,3-linked
10
11
Nasal mucosa
Sinus
Bronchus
bronchiole
Alveoli
Avian SAα2,3-linked receptors = red
Human SAα2,6-linked receptors = green
12
Why are pigs important
regarding pandemics ???
13
14
Avian SAα2,3-linked receptors = red
Swine SAα2,6-linked receptors = green
15
Pigs are thought to have an important
role in interspecies transmission of
influenza, because they have receptors
to both avian and human influenza virus
strains.
16
Why important ?????
17
Pandemics
the three important criteria for a new
pandemic influenza virus—ie, the ability to
replicate in human beings and the absence of
antibodies to the virus in the human
population at large. The third criterium is the
potential to rapidly spread from man to man.
18
Swine flu: Mortality??
19
Country
Cases Deaths
MEXICO
4174
80
U.S.A
6552
9
CANADA
805
JAPAN
345
SPAIN
133
UK
122
PANAMA
Total
76
12515
1
0
0
0
0
91 (0.7%)
20
EID 2006;12: 15-22
Case fatality rates were >2.5%, compared to
<0.1% in other influenza pandemics.
21
22
23
24
High school A with 2,686 students
and 228 staff members.
April 23–24, a total of 222 students
got ill.
During April 26–28, 44 (86%) of 51
specimens collected were tested
positive at CDC for S-OIV,
25
Median age = 15 years (range: 14–21 years).
All were students,
The only adult was a teacher aged 21 years.
None of the 44 patients reported recent travel
to California, Texas, or Mexico.
26
27
28
Further enhanced surveillance
among all students, staff members,
and family members of persons at
high school A indicated widespread
influenza-like symptoms, with
hundreds of students and many staff
members reporting symptoms that
met the case definition for ILI.
29
30
31
Several students participating in the
on-line survey (none of whom had
confirmed S-OIV) reported travel to
Mexico during the week before April
20; an undetermined number were
symptomatic at the time of survey
participation.
32
Swine flu: Morbidity??
33
34
35
36
N Engl J Med 2009;361:1-10
37
38
Severe Swine Flu: Who ???
39
Of the 22 hospitalized patients for whom
data were available, 4 (18%) were
children under the age of 5 years, and 1
patient (4%) was pregnant. Nine patients
(41%) had chronic medical conditions.
40
Severe Swine Flu: Old age???
41
42
March 1–April 30,2009
1,918 suspected cases
286 probable cases
97 confirmed cases
7 died
43
44
45
46
47
EID 2006;12: 15-22
Case fatality rates were >2.5%, compared to
<0.1% in other influenza pandemics.
48
49
Probable Scenario of Pandemic
Influenza Outbreak.
What?
When?, How long?
Where?
Who?
Why?
50
Where shall they begin?
51
First wave of influenza epidemic: In the community
Where & Who?
52
School absentee
Adult pneumonia
ER visits
Pediatric pneumonia
53
54
High school A with 2,686 students
and 228 staff members.
April 23–24, a total of 222 students
got ill.
During April 26–28, 44 (86%) of 51
specimens collected were tested
positive at CDC for S-OIV,
55
Cough ( 43 patients [98%]),
Subjective fever (42 [96%]),
Fatigue (39 [89%]),
Headache (36 [82%]),
Sore throat (36 [82%]),
Runny nose (36 [82%]),
Chills (35 [80%]),
Muscle aches (35 [80%]).
56
Nausea (24 [55%]),
stomach ache (22 [50%]),
diarrhea (21 [48%]),
shortness of breath (21 [48%]), and
joint pain (20 [46%])
57
Second Wave of Epidemic: ? in the Hospitals
58
Nosocomial transmission was
the primary acceleration of
SARS infections accounting
for 72% of cases in Toronto,
41% of cases in Singapore and
55% of probable cases in
Taiwan.
Ref.: Booth CM et al. JAMA 2003;289:2801-9
James L et al. Publ Health 2006;120:20-26
59
CDC. MMWR 2003;52:461-6
A ProMED-mail post
<http://www.promedmail.org>
Date: 2 May 2009
From: Oliver Schmetzer
<[email protected]>
Human to human transmission, Germany
According to the press release of the
president Juerg Hacker of the German
health institute (Robert-Koch-Institute)
from 2 May 2009:
60
“The 2nd suspected human-to-human
infection has been confirmed. In addition
to the 42-year-old nurse, the 38-year-old
patient which shared the room with the
initial in Mexico infected 37-year-old man
has been tested positive for A/H1N1…..”
61
Where in the hospital did the outbreak
occur?
62
EID 2004;10:782-788
Thirty- one cases of SARS occurred after
exposure in the emergency room of the
National Taiwan University Hospital.
63
Crit Care Med 2005;33:S53-S60
Four hospitals had major nosocomial
outbreaks of SARS. Three of these
outbreaks occurred in ICUs.
64
“Within 18 hrs of presentation, the
patient was admitted to the ICU and 3
hrs later was placed in an isolation
room.This 21-hr period of unprotected
contact led to128 cases of SARS
resulted from transmission of the virus
within this hospital. (42% HCWs, 28%
patients or visitors, and 30% household
contacts).”
65
73 ICU beds were closed during various
phases of the SARS outbreak, representing
38% of the tertiary-care university medical–
surgical ICU beds and 33% of the community
ICU beds in Toronto.
Ref.: Booth CM & Stewart TE. Crit Care Med 2005;33:S53-S60
66
How long shall the epidemic last???
67
Singapore: James L et al. Publ Health 2006;120:20-6
68
Taiwan: EID 2004;10:777-781
69
Beijing: EID 2004;10:25-31
70
71
72
EID 2004;10:771-776
73
SARS and Critical Care: Lessons Learned
“the most important of which is preparedness.
We were not prepared for SARS, nor did we
have a systemwide critical care
communication strategy in place..... the most
important limitation in the response to SARS
was the absence of a coordinated leadership
and communication infrastructure.
BoothCM,Stewart TE. Severe acute respiratory syndrome and
critical care medicine:The Toronto experience. Crit Care Med
2005;33:S53-S60
74
“Noah's ark was built before the rain.”
75
Personnels Preparedness:Keywords
Education &Training
Maximize Their Safety
76
77
Hospital Staffs Education
Routes of transmission
Handwashing
How to don and how to remove
personal protective gears
Wear N95 masks at meetings and
briefings in the hospital.
Limit social interactions.
78
Personnels Education Team
= ICNs
79
Personnels Preparedness:Keywords
Education &Training
Maximize Their Safety
(Handwashing & Masks)
(Tamiflu prophylaxis)
80
Exit the patient’s room: What to do?
“the first pair of gloves was removed, followed by
the hair net, the face shield, and the second pair of
gloves; next, hands were washed with quick-drying
antiseptic solution, and the gown was carefully
removed; then the hands were washed again before
the staff member left the room. In the hallway,
hands were washed, goggles removed and disposed
of, hands washed again, respirators removed,
hands washed, and finally, a new N95 respirator
was donned.”
81
EID 2004;10:280-6
Infection control training <2 hours was a
significant independent risk factors for
SARS infection.
82
83
Respiratory Viruses
Transmission: How?
Possible Modes of Spread
84
Hand-to-hand transmission of rhinovirus
colds. Gwaltney JM Jr et al. Ann Intern Med 1978 Apr;88(4):463-7
Virus on donors' hands was transferred to
recipients' fingers during 20 of 28 (71%) 10second hand-contact exposures. These
findings support the concept that hand
contact/self-inoculation may be an important
natural route of rhinovirus transmission.
85
Aerosol transmission of rhinovirus colds.
Dick EC et al. J Infect Dis 1987; 156:442-448
“(donors) and susceptible men (recipients) who played cards
together for 12 hr. In three experiments the infection rate of
restrained recipients (10 [56%] of 18), who could not touch
their faces and could only have been infected by aerosols,
and that of unrestrained recipients (12[67%] of 18), who could
have been infected by aerosol, by direct contact, or by
indirect fomite contact, was not significantly different (chi 2 =
0.468, P = .494). …These results suggest that contrary to
current opinion, rhinovirus transmission, at least in adults,
occurs chiefly by the aerosol route.”
86
Modes of transmission of respiratory
syncytial virus. Hall C:J. Pediatr 1981;99:100-103
The first group, called "cuddlers".These staff wore gowns but
no mask or gloves. The second group, called "touchers,"
touched with ungloved hand surfaces likely to be
contaminated with the baby's secretions when the infant was
out of the room. They then gently rubbed the mucous
membranes of their nose or eye, The third group, called
"sitters," was exposed to an infected baby by sitting at a
distance of >1.8 m from the bed. They wore gowns and
gloves, but no masks. Only the cuddlers and touchers
became infected, which suggests that routes that require
close or direct contact with infectious secretions and selfinoculation were the major or most effective means of
87
transmission.
3 possible mechanisms
1. Contacts (Direct or Indirect (Fomites)
self-inoculation after touching
contaminated surfaces
2. Droplets or large particles
>5 microns particles
close person-to-person contact
at a distance of < 0.9 m (3 feet)
88
3 Possible Modes of Spread
3. small-particle aerosols (airborne)
 < 3-5 microns
 generated by coughing or
sneezing
 traverse distances > 1.8 m
 such as occur with measles,
varicella, and sometimes
influenza
89
90
Effectiveness of measures to
prevent SARS
A case-control study in 5 Hong
Kong hospitals
241 non-infected and 13
infected staffs
about use of mask, gloves,
gowns, and hand-washing
Ref. : Seto WH et al.Lancet2003;361:1519-20
91
Effectiveness of measures to
prevent SARS
Results:
69 staffs who reported use of all four
measures were not infected. Fewer staff
who wore masks (p=0·0001), gowns
(p=0·006), and washed their hands (p=0·047)
became infected compared with those who
didn't, but stepwise logistic regression was
significant only for masks(p=0·011).
Ref. : Seto WH et al.Lancet2003;361:1519-20
92
Front line of defence: Screening area & ER
93
Screening:
WHO ???
94
N Engl J Med 2009;361:1-10
95
96
Of 178 patients,
145 (82%) reported recent travel to
Mexico, and
four (2%) reported travel to the United
States.
Among those who had not traveled to
Mexico, 17 (52%) reported contact with a
returning traveler from Mexico.
97
Country
Cases Deaths
MEXICO
4174
80
U.S.A
6552
9
CANADA
805
JAPAN
345
SPAIN
133
UK
122
PANAMA
Total
76
12515
1
0
0
0
0
91 (0.7%)
98
EID 2004;10:771-776
Tent assessment clinic was constructed within 1 week. It
contained eight negative-pressure isolation rooms built
with pipe framing and plastic walls and ceilings. Areas
for clerical work, registration, and changing personal
protective equipment were also created. Other
components included an area for case review, a leadlined x-ray room, and an x-ray viewing room.
99
Emergency Department and SARS Assessment Clinic
North York General Hospital, Toronto
100
Emergency Department and SARS Assessment Clinic
North York
General Hospital, Toronto
101
T= Triage area and body temperature screening station,
C = Cardiopulmonary resuscitation area,
L = Low-risk area for patients with fever or cough,
102
H = High-risk area for suspect and cases of SARS.
“Our ER continued to operate efficiently
throughout the critical period, even
when the other 2 emergency
departments in this city of 3 million
people were shut down.”
“No secondary or tertiary transmission
has been discovered.”
“less than 1% of patients seen actually
had SARS”
103
EID 2004;10:777-781
104
105
Screening area: Essential Elements
One way traffic
Waiting area (each seat >3 feet apart,
mask and portable alcohol-based hand
washing for everybody)
Triage area
106
107
CPR area
Low risk area
High risk area
X-ray area
Sputum collection area
Area for changing personal
protective equipment
??? Portable toilets
108
Traffic Control: ? SARS Police
Security ensured that unauthorized persons
did not enter the hospital; a security staff
member, with a nurse, escorted SARS
patients on transports between departments,
logging the date, time, and persons involved
in the transfer.
109
Identification tags
Security and traffic officers
Recorder & record forms (logging
the date, time, and persons involved,
?? computerized )
Back-up consultants for ambiguous
cases.
110
Adverse Effects of setting up a fever clinic
EID 2004;10:210-216
111
Fever Clinics
EID 2004;10:777-781
Officials either constructed or retrofitted
existing facilities to create SARS
evaluation centers (i.e.,“Fever Clinics”)
...in both Toronto andTaiwan, no
transmission was reported in these
facilities.
112
1. Toll free.
2. 52 physicians,(6 hr. shift) between 8
a.m. and 10 p.m. daily
3. 86% of Teipei residents knew of the
project from television.
113
Objectives of fever hotline:
1.Aimed at reduce clinic visits by the
“worried well,”
2. Prepared the potential cases
before going to see the doctors.
3. Prepared the transportation of
potential patients.
.
114
115
During June 1 to 10, a total of 11,228 calls
were made
Of the 4,000 telephone numbers dialed, 2,999
numbers were invalid, unanswered, or
refusals.
Persons were advised to seek further medical
evaluation in 28% (n = 3,100) of calls.
Only 18 were identified as being at high risk
for SARS.
116
117
118
How to tranport febrile patient to the hospital???
Dedicated ambulance service for
SARS cases were set up during the
2003 outbreak of SARS in Singapore.
James L et al. Publ Health 2006;120:20-26
119
120
SARS Ward, Taiwan. EID 2004;10:1187-1194 121
122
Tai DYH. Ann Acad Med Singapore 2006;35:368-73
123
124
Resources
Personnels
Equipments
125
Patient: Nurse Ratio
At the beginning of the outbreak, the ratio was
approximately 4–5 patients per nurse, a potentially
dangerous ratio that could lead to transmission.
During SARS II, the ratio was 1:1 if the patient was
on oxygen requiring hourly monitoring and 2:1 for
more stable patients. In the ICU, the ratio was two
nurses per patient,
126
Patient: Physician Ratio
The patient-to-physician ratio was 5–10 SARS
patients per physician. (including emergency
department physicians, general internists, family
physicians, surgeons, and anesthesiologists)
One infectious disease consultant was assigned to
each SARS ward, and one also covered the SARS
ICU for a ratio of 20to 30 SARS patients per
infectious disease consultant.
127
Shortage of hospital personnels
Up to 40% of the workforce will not be available due
to personal illness, illness in a family member,
providing care for children at home due to school
closure or due to anxiety leading to work avoidance.
US Department of Health and Human Services. HHS pandemic
influenzaplan; November 2005. http://www.hhs.gov/pandemicflu/plan/pdf/
128
Martinello RA. Preparing for avian influenza.
Current Opinion in Pediatrics 2007, 19:64–70
129
Hospital personnels
Up to 40% of the workforce will not be available due
to personal illness, illness in a family member,
providing care for children at home due to school
closure or due to anxiety leading to work avoidance.
US Department of Health and Human Services. HHS pandemic
influenzaplan; November 2005. http://www.hhs.gov/pandemicflu/plan/pdf/
130
????Dedicated Avian Flu Care Team ???
“Facilities may find it useful to
create dedicated teams of clinical
and ancillary staff to limit the
number of persons interacting with
potentially contagious patients and
to assure appropriate use of
infection control precautions.”
131
Hospital personnels
“First Avian Flu Care Teams”
ER & ICU
132
??? Avian flu caregivers dormitory???
133
Use the new non-suction oxygen mask with highly
efficient Virus Filters attached
134
Intubation: ?When?
if an oxygen flow over 15Liter/min or a
frequency of over 30 breaths/min is still not
able to maintain oxygen saturation.
135
Is wearing a surgical mask acceptable?
Answer: No. Recent research has shown that many
surgical masks do not do a good job of removing all
TB bacteria. Some surgical masks fit so poorly that
they provide very little protection from any
airborne hazard.
Only NIOSH-certified respirators should be worn
for TB protection. A surgical mask is not a
respirator.
NIOSH. A respiratory protection guide for heathcare workers 1995 pp.5
136
137
Powered Air Purifying Respirators (PAPRs)138
Powered Air Purifying Respirators (PAPRs)
139
PAPRs with loose-fitting facepieces, hoods, or
helmets have <4% inward leakage under
routine conditions. Therefore, a PAPR might
offer lower levels of face-seal leakage than
nonpowered, half-mask respirators.
European Committee for Standardization. Respiratory protective
devices: filtering half masks to protect against particles—
Requirements,testing, marking. Europaishe Norm 2001;149.
140
Filter
141
142
Beware! :The filter on the expiratory end should be
changed if its flow resistance has increased >
143
3cmH2O.
Caution!: Pay attention to filters which may have
an influence on the function of some ventilators.
144
In the inspiratory limb of
the circuit the Virus filter
is placed on the entrance
of Humidifier.
In the expiratory limb of
the circuit the Virus filter
is placed on the exit of the
isolation system.
145
Personnels Preparedness:Keywords
Education &Training
Maximize Their Safety
(Handwashing & Masks)
(Tamiflu prophylaxis)
146
Organisms
Infection
.
1
Disease
.
2
Death
3
.
Pre-exposure
Prophylaxis?
147
Viruses from 13 (20%) of 64 patients have
been tested for resistance to antiviral
medications.
All exhibited IC50 values characteristic of
oseltamivir- and zanamivir-sensitive influenza
viruses.
148
149
NYC Department of Health and Mental
Hygiene (DOHMH) is recommending
treatment with oseltamivir for:
1) hospitalized persons with suspected,
severe febrile unexplained respiratory
illness pending testing for swine
influenza, or
150
2) patients with mild (uncomplicated)
influenza-like illnesses and
underlying conditions (such as,
chronic cardiovascular or renal
disorders or immunosuppression)
that increase the risk for more
severe illness because of influenza.
151
DOHMH is recommending
treatment for any patient with
mild (uncomplicated)
influenza-like illnesses
permissively only if started
within 48 hours of symptom
onset.
152
Prophylactic Tamiflu???
153
JAMA 2001;285:748
154
Participants: Three hundred seventyseven index cases(ICs), 163 (43%) of
whom had laboratory confirmed
influenza infection, and 955 household
contacts (aged >12 years) of all ICs (415
contacts of influenza-positive ICs).
155
Interventions: Household contacts were
randomly assigned by household cluster
to take 75 mg of oseltamivir (n=493) or
placebo (n=462) once daily for 7 days
within 48 hours of symptom onset in the
index case. The index cases did not
receive antiviral treatment.
156
157
Results: In contacts of an influenzapositive index case, the overall protective
efficacy of oseltamivir against clinical
influenza was 89% for individuals (95%
CI, 67%-97%; P<.001) .
158
NEJM 1999;341:1336
159
Design:Placebo controlled, double-blind
trials at different U.S. sites during the winter
of 1997–1998.
Methods:1559 healthy, nonimmunized adults
were randomly assigned to receive either oral
oseltamivir (75 mg given once or twice daily, for a
total daily dose of 75 or 150 mg) or placebo for six
weeks during a peak period of local influenza virus
activity. The primary end point with respect to
efficacy was laboratory-confirmed influenza-like
illness.
160
Results:For culture-proved influenza, the rate
of protective efficacy in the two oseltamivir
groups combined was 87 percent (95 percent
confidence interval, 65 to 96 percent). The
rate of laboratory-confirmed influenza
infection was lower with oseltamivir than with
placebo (5.3 percent vs. 10.6 percent, P<0.001).
161
Lancet 2004; 364: 759–65
162
“We identified a neuraminidase
mutation in viruses isolated from nine
(18%) of the 50 oseltamivir-treated
patients. On day 5 or 6, the level of virus
shedding was reduced in 18 of 19
patients without resistant viruses and in
four of six with resistant viruses.”
163
Consider antiviral prophylaxis for all
health-care personnel, regardless of
their vaccination status, if
the outbreak is caused by a variant of
influenza virus that is not well matched
by the vaccine.
CDC’s GUIDELINES AND RECOMMENDATIONS
Infection Control Guidance for the Prevention and Control of
Influenza in Acute-Care Facilities. ( February 8, 2007)
164
Prophylactic Tamiflu???
165
166
Antiviral prophylaxis is being
recommended for
1) health-care workers who provided
care to patients with suspected swine
influenza without using appropriate
personal protection,or
2) asymptomatic household or other
close contacts of ill persons of
suspected swine influenza who are at
higher risk for complications of influenza
or are health-care workers themselves.
167
168
169
Personnels Vaccination???
170
171
6 additional cases.
Cases 1&2 : an adolescent girl aged
16 years and her father aged 54
years went to a clinic with acute
respiratory illness. The father had
received seasonal influenza vaccine
in October 2008; the daughter was
unvaccinated. Both had self-limited
illnesses.
172
Case 4: A woman aged 41 years with an
autoimmune disease was hospitalized
because of fever, headache, sore throat,
diarrhea, vomiting, and myalgias.She
recovered and was discharged on April
22. The woman had not been vaccinated
against seasonal influenza viruses.
173
N Engl J Med 2009;361:1-10
174
175
176
Surveillance & Data Collection Team
In-patients surveillance: When a new SARS
case was diagnosed in a hospital, the hospital
initiated active contact tracing of all HCWs,
inpatients and visitors who may have had
contact with the case. HCWs, and or other
patients with unprotected exposure were
further quarantined.
.
177
Disharged Patients
“Discharged patients were kept under
telephone surveillance for a further 10
days.Those who was unwell and
required hospital admission, was readmitted to TTSH and managed as a
suspect SARS until SARS was actively
excluded.”
178
Hospital staffs surveillance:
Daily telephone- monitoring record
of all hospital staffs who had contact
with SARS patients.
179
Sick personnel
Staff with a fever were not allowed to
work and required to stay at home or in
their dormitory and limit social contact.
180
181
Psychological Team
At NYGH, we put together a SARS
psychological team (including social workers,
psychiatric crisis nurses, psychiatrists, and
infectious disease specialists) that developed a
plan to manage the psychological impact on
patients and staff..
182
183
Public information team
TV or radio “SARS Channel”
Daily briefing of the situation.
Education ( eg. handwashing, not going
to work or school if they had a fever etc.)
184
185
Resources
Personnels
Equipments
186
Equipments:
Even in Singapore, N95 masks were of
limited supply therefore HCWs wore
them throughout the hospital and reused them for about a week. Thus far,
this behaviour did not result in further
SARS infection. James L et al. Publ Health
2006;120:20-26
187
188
Home-made respiratory mask
Dato VM et al. EID 2006;12:1033-1034
189
190
Research Team
“Research is imperative during such an
outbreak, particularly for a new disease…
The ethics board was prompt in attending to
required approvals, often a lengthy process.”
191
192
System Thinking and Lobby Team
BoothCM,Stewart TE. Severe acute respiratory
syndrome and critical care medicine:The Toronto
experience. Crit Care Med 2005;33:S53-S60
193
Establishing a Ministerial Committee and
SARS Task Force. consisted of members from
the Ministries of Health, Foreign Affairs, Home
Affairs, Defence,Education, Environment,
Transport and the Ministry of Information &194
Communications
Examples of public issues to be decided.
?Laws amendment regarding quarantine.
Incoming travellers
(prohibit?,screening?, quarantine?)
International agreement
(exchange of data & aids)
?Schools & Hospitals closure.
?Mass prophylaxis
195
System Thinking and Lobby Team
Important issues that were considered by
this group included the following:
whether to create “SARS hospitals”
BoothCM,Stewart TE. Severe acute respiratory
syndrome and critical care medicine:The Toronto
experience. Crit Care Med 2005;33:S53-S60
196
EID 2004;10:25-31
Through June 2003, a total of 2,521 patients
with probable cases of SARS were
hospitalized in Beijing. The outbreak peaked
during the 3rd and 4th weeks in April, when
hospitalizations for probable SARS exceeded
100 cases for several days,
197
.
198
Local shortages of isolation rooms,
intensive care facilities, and hospital
beds were addressed by dispatching
specially equipped ambulances to
transfer SARS patients to designated
facilities. An anticipated shortage of
hospital beds for care and isolation of
SARS patients prompted authorities to
construct a new 1,000-bed hospital in 8
days.
199
Centralized Influenza Hospital???
Singapore:Tan Tock Seng Hospital
(TTSH) was designated as the SARS
Hospital on 22nd March 2003. All suspect
SARS cases throughout Singapore
island were immediately referred for
assessment and further management to
TTSH.
James L et al. Publ Health 2006;120:20-26
200
Canceling elective surgeries and
preserve the care of emergent patients
(such as trauma, cardiac, neurosurgery,
and transplant)...... Such a response
appears to require a regionalized
approach or systemwide thinking to the
delivery of critical care.
201
Co-ordination between SARS
Hospital and other hospitals:
The general public were informed to
seek medical care at other hospitals for
emergency and specialized care.
In order to have the capacity to absorb
the cases diverted from TTSH, other
hospitals reduced their elective
operations and admissions.
202
SARS in Singapore: Role of Internet
SARSWeb for all hospitals:
Updated list of SARS and home
quarantine cases and their contacts
(family members and healthcare
workers)
To facilitate identification of suspect
cases of SARS
Need password
203
Public Health Team, Toronto
a mobile public health outbreak management team.
“swift contact tracing and the quarantine of
persons identified as having had unprotected
exposure to a SARS patient”
204
JAMA 2001;285:748
205
206
EID 2005;11:278-282
207
208
“Most of the quarantined persons
were confined to their homes for 10–
14 days.”
“Public health nurses would bring
the quarantined persons 3 meals
everyday and sometimes helped
them with odd jobs such as washing
clothes or taking care of pets.”
209
SARS quarantine: Singapore Style
A Singapore security agency installed an
electronic picture (ePIC) camera at the home
of each contact.
Quarantined persons were required to stay at
home for 10 days and to minimise interaction
with other people.They were called on the
telephone daily to make sure that they did not
break the quarantine and were well. They had
to appear in front of the ePIC camera each
time they were called. James L et al. Publ Health
210
2006;120:20-26
Airport screening???
Aircrews should notify airport officials regarding
febrile passengers before landing.
211
Entry Screening???
EID 2004;10:1900
212
Thermal Scanner????
213
214
Entry Screening???
Data from a worldwide survey indicate
that among 72 patients with imported
probable or confirmed SARS cases, 30
(42%) had onset of symptoms before or
on the same day as entry into the
country and symptoms developed in 42
patients (58%) after entry.
215
In Taiwan, incoming travelers from
affected areas were quarantined;
probable or suspected SARS was
diagnosed in 21 (0.03%) of 80,813.
None of these 21 was detected by
thermal scanning when they entered
Taiwan.
216
BMJ 2005;331:1242–3
“Entry screening is unlikely to be effective in
preventing or delaying an epidemic resulting from
217
the importation of SARS or influenza.”
The most important disease vector
218
In Flight Transmission of SARS?
EID 2004;10:1900
219
220
In Flight Transmission of Flu?
Human to human transmission, Germany
A ProMED-mail post <http://www.promedmail.org>
Date: 3 May 2009 From: "Oliver Schmetzer"
<[email protected]> [Edited]
Update, 3 May 2009
In addition to the 2 human-to-human
transmissions in Bavaria, the infection of a
couple in Frankfurt/Oder in Brandenburg has
been confirmed to be A/H1N1. The couple was
infected on a flight from Mexico likely by the
221
confirmed case in Hamburg.
Closing down airports????
222
PLoS Med 3(10): e401.DOI:
10.1371/journal.pmed.0030401
223
PLoS ONE 2(5): e401.
doi:10.1371/journal.pone.0000401
224
a 90%, 99% or 99.9% reduction in
imported
infections might delay the peak of the US
pandemic by 1.5, 3, or 6 weeks,
respectively
225
??? Mass prophylaxis with oseltamivir ???
226
NEJM 1999;341:1336
227
Design:Placebo controlled, double-blind
trials at different U.S. sites during the winter
of 1997–1998.
Methods:1559 healthy, nonimmunized adults
were randomly assigned to receive either oral
oseltamivir (75 mg given once or twice daily, for a
total daily dose of 75 or 150 mg) or placebo for six
weeks during a peak period of local influenza virus
activity. The primary end point with respect to
efficacy was laboratory-confirmed influenza-like
illness.
228
Results:For culture-proved influenza, the rate
of protective efficacy in the two oseltamivir
groups combined was 87 percent (95 percent
confidence interval, 65 to 96 percent). The
rate of laboratory-confirmed influenza
infection was lower with oseltamivir than with
placebo (5.3 percent vs. 10.6 percent, P<0.001).
229
??? Mass prophylaxis with oseltamivir ???
230
231
Antiviral prophylaxis of household
members is effective in reducing
cumulative attack rates by at least
one third but requires an antiviral
stockpile large enough to treat 46%
or 57% of the population for the
moderate and high transmissibility
scenarios, respectively.
232
No intervention
Prophylaxis
Quarantine
233
234
Hospital Preparedness
and Avian influenza
Khachornsakdi Silpapojakul MD
Prince of Songkla University
Hat yai, Songkla, Thailand
235
SARS: PSU Experience
236
Conceptual Framework
Organisms
Infection
.
1
Disease
.
2
Death
3
.
?
237
Respiratory Viruses
Transmission: How?
Possible Modes of Spread
238
Hand-to-hand transmission of rhinovirus
colds. Gwaltney JM Jr et al. Ann Intern Med 1978 Apr;88(4):463-7
Virus on donors' hands was transferred to
recipients' fingers during 20 of 28 (71%) 10second hand-contact exposures. These
findings support the concept that hand
contact/self-inoculation may be an important
natural route of rhinovirus transmission.
239
Aerosol transmission of rhinovirus colds.
Dick EC et al. J Infect Dis 1987; 156:442-448
“(donors) and susceptible men (recipients) who played cards
together for 12 hr. In three experiments the infection rate of
restrained recipients (10 [56%] of 18), who could not touch
their faces and could only have been infected by aerosols,
and that of unrestrained recipients (12[67%] of 18), who could
have been infected by aerosol, by direct contact, or by
indirect fomite contact, was not significantly different (chi 2 =
0.468, P = .494). …These results suggest that contrary to
current opinion, rhinovirus transmission, at least in adults,
occurs chiefly by the aerosol route.”
240
Modes of transmission of respiratory
syncytial virus. Hall C:J. Pediatr 1981;99:100-103
The first group, called "cuddlers".These staff wore gowns but
no mask or gloves. The second group, called "touchers,"
touched with ungloved hand surfaces likely to be
contaminated with the baby's secretions when the infant was
out of the room. They then gently rubbed the mucous
membranes of their nose or eye, The third group, called
"sitters," was exposed to an infected baby by sitting at a
distance of >1.8 m from the bed. They wore gowns and
gloves, but no masks. Only the cuddlers and touchers
became infected, which suggests that routes that require
close or direct contact with infectious secretions and selfinoculation were the major or most effective means of
241
transmission.
3 possible mechanisms
1. Contacts (Direct or Indirect (Fomites)
self-inoculation after touching
contaminated surfaces
2. Droplets or large particles
>5 microns particles
close person-to-person contact
at a distance of < 0.9 m (3 feet)
242
3 Possible Modes of Spread
3. small-particle aerosols (airborne)
 < 3-5 microns
 generated by coughing or
sneezing
 traverse distances > 1.8 m
 such as occur with measles,
varicella, and sometimes
influenza
243
Darin Areechokchai, C. Jiraphongsa, Y.
Laosiritaworn, W. Hanshaoworakul, M. O'Reilly
Investigation of Avian Influenza (H5N1)
Outbreak in Humans --- Thailand, 2004
MMWR Morb Mortal Wkly Rep. 2006;55 (Suppl 1):3-6.
244
OR (95% CI)
Dead poultry around the house
5.6 (1.5-20.7)
Being =< 1m. away from dead poutry 13.0 (1.6-19.3)
Direct Touching of sick poultry
5.6 (1.5-20.7)
Direct Touching of dead poultry
29.0 (2.7-306.2)
Plucking poultry
14.0 (1.3-152.5)
Hx of contact with H5N1 patients
0.9 (0.2-4.4)
245
Transmission of Influenza Viruses
Seasonal
Influenza in
Humans
Avian Influenza in
Humans
Droplet
Yes
Probably (human to human)
Airborne
Rare
Unknown
Contact
Yes
Yes (bird to human)
246
Patients
H5N1
1y
HCWs
Infection
2y
Disease
Death
3y
Screening
247
248
Patients
H5N1
HCWs
1y
Infection
2y
Disease
Death
3y
Screening
Handwashing
249
250
251
Published: 9 February 2007
BMC Infectious Diseases 2007, 7:5 doi:10.1186/1471-2334-7-5
252
253
254
Patients
H5N1
HCWs
Infection
1y
2y
Disease
Death
3y
Screening
Handwashing
Mask for the patient
255
256
Efficiency of surgical masks in ‘sneezing’
experiments. Madsen PO & Madsen RE. AJS 1967;114:41
Type of masks
Efficiency
Polypropylene
98.8%
Polyester & Rayon
98.4%
Glass fibers
97.3%
257
258
Measuring the speed of the wind from the mouth
with an ultrasonic anemometer.
259
Compared with the
airspeed without
masks, all three masks
reduced thespeed to
less than 1/10.
260
261
262
% spore recovered
No mask (n=8)
24.6%
American Hospital masks (n=8)
-conventionally worn
24.2%
-taped masks
0.00%
3M masks (n=8)
-conventionally worn
30.9%
-taped masks
0.00%
Ref.:Pippin DJ et al. J Oral Maxillofac Surg 1987;45:319
263
Patients
H5N1
HCWs
Infection
1y
2y
Disease
Death
3y
Screening
Handwashing
Mask for the patient
Mask for personnel
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
Effectiveness of measures to
prevent SARS
A case-control study in 5 Hong
Kong hospitals
241 non-infected and 13
infected staffs
about use of mask, gloves,
gowns, and hand-washing
Ref. : Seto WH et al.Lancet2003;361:1519-20
284
Effectiveness of measures to
prevent SARS
Results:
69 staffs who reported use of all four
measures were not infected. Fewer staff
who wore masks (p=0·0001), gowns
(p=0·006), and washed their hands (p=0·047)
became infected compared with those who
didn't, but stepwise logistic regression was
significant only for masks(p=0·011).
Ref. : Seto WH et al.Lancet2003;361:1519-20
285
286
287
288
289
290
291
292
293