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Title: Novel H1N1 (Swine) Epidemiology


1
  • Novel H1N1 (Swine) Epidemiology Control
  • Ahmed Mandil
  • Prof of Epidemiology
  • Dept of Family Community Medicine
  • College of Medicine, King Saud University

2
HEADLINES
  1. Influenza Virus
  2. Definitions
  3. Introduction
  4. Spread/Transmission
  5. Timeline/Facts
  6. Response
  7. Case-Definitions
  8. Treatment
  9. Other Protective Measures
  10. Conclusion Recommendations

3
Virus
Credit L. Stammard, 1995
4
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

5
(No Transcript)
6
Lessons Learned formPast 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
  • Cytokine Storm?
  • 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
  • World War I 8.3 million military deaths over 4
    years
  • 25-35 of the world infected

7
Lessons Learned formPast 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
  • Does not change population susceptibility
  • Delay spread in Australia later milder strain
    causes infection there
  • Temporary banning of public gatherings, closing
    schools potentially effective in case of severe
    disease and high mortality
  • Delaying spread is desirable
  • Fewer people ill at one time improve capacity to
    cope with sharp increase in need for medical care

8
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-to-human spread of
    swine flu viruses have been documented

9
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

10
Swine Influenza A(H1N1) Transmission Through
Species
Reassortment in Pigs
11
Swine Influenza A(H1N1) 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
  • North American swine
  • North American avian
  • North American human and
  • Eurasian swine

12
Swine Influenza A(H1N1) Global Response
  • The WHO raises the alert level to Phase 6
  • WHOs 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
13
Swine Influenza A(H1N1)Status Update
  • GLOBALLY March 1-December 23
  • At least 11,516 Deaths
  • Africa Region (AFRO) 109
  • Americas Region (AMRO) 6,670
  • Eastern Mediterranean Region (EMRO) 663
  • Europe Region (EURO) 2,045
  • South-East Asia Region (SEARO) 990
  • Western Pacific Region (WPRO) 1,039

ECDC reported a total of 12,776 deaths December
28, 2009
Source WHO
14
Swine Influenza A(H1N1) CDC Estimates from
April-November 14, 2009, By Age Group
2009 H1N1 Mid-Level Range Estimated Range
Cases    
0-17 years 16 million 12 million to 23 million
18-64 years 27 million 19 million to 38 million
65 years and older 4 million 3 million to 6 million
Cases Total 47 million 34 million to 67 million
Hospitalizations    
0-17 years 71,000 51,000 to 101,000
18-64 years 121,000 87,000 to 172,000
65 years and older 21,000 15,000 to 29,000
Hospitalizations Total 213,000 154,000 to 303,000
Deaths    
0-17 years 1,090 790 to 1,550
18-64 years 7,450 5,360 to 10,570
65 years and older 1,280 920 to 1,810
Deaths Total 9,820 7,070 to 13,930
Source CDC. http//www.cdc.gov/h1niflu/surveillan
ceqa.htm
15
Pandemic (H1N1) 2009 in the EMR as of 6 November,
2009
Country Cumulative number of confirmed cases Cumulative number of deaths Trend
Kuwait 6, 640 17 Increasing
UAE 79 0 NA
Bahrain 793 6 NA
Lebanon 761 2 NA
Egypt 1, 592 5 Increasing
Saudi Arabia 4, 119 28 NA
Palestine 777 1 Increasing
Morocco 484 0 Increasing
Jordan 2, 050 3 Increasing
Qatar 23 1 NA
Yemen 629 17 Increasing
Oman 3, 329 25 Increasing
Iran 1, 638 22 Increasing
Tunisia 1, 285 0 Increasing
Iraq 1, 080 7 Increasing
Libya 21 0 Unchanged
Syria 160 6 Increasing
Afghanistan 772 10 Increasing
Sudan 7 0 Unchanged
Pakistan 5 0 Unchanged
Djibouti 9 0 Unchanged
Somalia 2 0 Unchanged
Total 26,400 150
  • 22/22 countries affected
  • Regular reports from 17 countries 26,400
    confirmed cases and 150 deaths.
  • Localized to moderate geographical distribution.
  • Increasing trend in most of the countries
  • Low to moderate intensity
  • Low to moderate impact on the health system

16
Pandemic H1N1 2009 in the EMR as of 6 November,
2009
17
The Epidemic Curve
Initiation
Acceleration
Peak
Decline
aths
20
15
Proportion of total cases, consultations,
hospitalisations or de
10
5
0
1
2
3
4
5
6
7
8
9
10
11
12
Week
Single-wave profile showing proportion of new
clinical cases, consultations, hospitalisations
or deaths by week. Based on London, second wave
1918.
18
Aims of community reduction of influenza
transmission mitigation
  • Delay and flatten epidemic peak.
  • Reduce peak burden on healthcare system and
    threat.
  • Somewhat reduce total number of cases.
  • Buy a little time.

No intervention
Daily cases
Days since first case
19
Swine Influenza A(H1N1) Mediterranean Middle
East Confirmed Deaths
As of December 28, 2009
n1,246
Source ECDC
20
Global Distribution of Reported Laboratory
Confirmed Cases Deaths of Swine Influenza
A(H1N1), December 23, 2009
Source WHO
21
Geographic Spread of Influenza ActivityBased
Upon Country Reporting, Week 50, 2009 (07-23
December)
Source WHO
22
Impact on Healthcare Services Based Upon Degree
of Disruption, As a Result of Acute Respiratory
DiseasesWeek 50, 2009 (07-13 December)
Source WHO
23
Number of Specimens Positive for Influenza
Sub-Type
Source CDC
24
Laboratory-Confirmed Cases Deaths of New
Influenza A(H1N1) by WHO Regions, September 20,
2009
At least 318,925 Cases Over 3917 Deaths Overall
Case-Fatality Rate (CFR) in Confirmed 1.2
CFR 2.5
CFR 0.4
CFR 0.3
CFR 1.1
CFR 0.5
CFR 0.6
Given that countries are no longer required to
test and report individual cases, the number of
cases reported actually understates the real
number of cases.
Source WHO
25
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

26
Comparison of Available Influenza Diagnostic
Tests1
Influenza Diagnostic Tests Method Availability Typical Processing Time2 Sensitivity3 for 2009 H1N1 influenza Distinguishes 2009 H1N1 influenza from other influenza A viruses?
Rapid influenza diagnostic tests (RIDT)4 Antigen detection Wide 0.5 hour 10 70 No
Direct and indirect Immunofluorescence assays (DFA and IFA)5 Antigen detection Wide 2 4 hours 4793 No
Viral isolation in tissue cell culture Virus isolation Limited 2 -10 days - Yes 6
Nucleic acid amplification tests (including rRT-PCR) 7 RNA detection Limited8  48 96 hours 6-8 hours to perform test 86 100 Yes
Source CDC
27
Swine Influenza A(H1N1) Antiviral Protection
  • There are two flu antiviral drugs recommended
  • Oseltamivir or Zanamivir
  • 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 aspirin-containing 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 Reyes
    syndrome. For relief of fever, other anti-pyretic
    medications are recommended such as acetaminophen
    or non steroidal anti-inflammatory drugs.
  • Treatment is recommended for
  • All hospitalized patients with confirmed,
    probable or suspected novel influenza (H1N1).
  • Patients who are at higher risk for seasonal
    influenza complications
  • If patient is not in a high-risk group or is not
    hospitalized, healthcare providers should use
    clinical judgment to guide treatment decisions

Source CDC
28
Swine Influenza A(H1N1) Antiviral Protection
  • Antiviral Chemoprophylaxis for Treatment
  • Post-exposure Duration chemoprophylaxis is 10
    days after the last known exposure to novel
    (H1N1) influenza and may be considered in the
    following
  • Close contacts of cases (confirmed, probable, or
    suspected)
  • Health care personnel, public health workers, or
    first responders who have had a recognized,
    unprotected close contact exposure to a person
    (confirmed, probable, or suspected) during that
    persons infectious period.
  • Pre-exposure Antivirals should only be used in
    limited circumstances, and in consultation with
    local medical or public health authorities.
  • Antiviral Use for Control of Novel H1N1 Influenza
    Outbreaks
  • A cornerstone for the control of seasonal
    influenza outbreaks in nursing homes and other
    long term care facilities.
  • If outbreaks were to occur, it is recommended
    that ill patients be treated with oseltamivir or
    zanamivir and that chemoprophylaxis with either
    oseltamivir or zanamivir be started as early as
    possible to reduce the spread of the virus as is
    recommended for seasonal influenza outbreaks in
    such settings.
  • Children Under 1 Year of Age
  • Oseltamivir is not licensed for use in children
    less than 1 year of age. Because infants
    experience high rates of morbidity and mortality
    from influenza, infants with novel (H1N1)
    influenza virus infections may benefit from
    treatment using oseltamivir.

Source CDC
29
Swine Influenza A(H1N1) Antiviral Protection
Oseltamivir (Tamiflu) Oseltamivir (Tamiflu) Zanamivir (Relenza) Zanamivir (Relenza)
Treatment Prophylaxis 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)
Children 1523 kg 90 mg per day divided into 2 doses 45 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)
Children 2440 kg 120 mg per day divided into 2 doses 60 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)
Children gt40 kg 150 mg per day divided into 2 doses 75 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)
Dosing recommendations for antiviral treatment of
children younger than 1 year using oseltamivir.
Recommended treatment dose for 5 days. lt3 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. lt3
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
Source CDC
30
Swine Influenza A(H1N1) Vaccine Protection
  • Novel H1N1 vaccine available for since
    Mid-September
  • Seventh Harvard Pandemic Survey
  • 38 of Children in the US immunized
  • 50 Adults do not intend to be immunized
  • 35 of parents do not intend to get their
    children immunized
  • Novel H1N1 vaccine is not intended to replace the
    seasonal flu vaccine it is intended to be used
    along-side seasonal flu vaccine
  • Vaccines
  • Inactivated influenza virus vaccines
  • CSL Ltd. of Australia
  • Novartis Vaccines of Switzerland
  • Sanofi Pasteur of France
  • 800,000 pre-filled syringes were recalled are for
    young children, ages 6 months to 3 years in the
    US
  • GlaxoSmithKline (GSK) of UK
  • Sinovac Biotech of China
  • Live-attenuated virus vaccine
  • MedImmune LLC of US (nasal-spray)

31
Swine Influenza A(H1N1) Vaccine Protection
  • CDCs Advisory Committee on Immunization
    Practices (ACIP) recommends the following groups
    to receive the novel H1N1 influenza vaccine
  • Pregnant women because they are at higher risk of
    complications and can potentially provide
    protection to infants who cannot be vaccinated
  • Household contacts and caregivers for children
    younger than 6 months of age because younger
    infants are at higher risk of influenza-related
    complications and cannot be vaccinated.
    Vaccination of those in close contact with
    infants less than 6 months old might help protect
    infants by cocooning them from the virus
  • Healthcare and emergency medical services
    personnel because infections among healthcare
    workers have been reported and this can be a
    potential source of infection for vulnerable
    patients. Also, increased absenteeism in this
    population could reduce healthcare system
    capacity
  • All people from 6 months through 24 years of age
  • Children from 6 months through 18 years of age
    because we have seen many cases of novel H1N1
    influenza in children and they are in close
    contact with each other in school and day care
    settings, which increases the likelihood of
    disease spread, and
  • Young adults 19 through 24 years of age because
    we have seen many cases of novel H1N1 influenza
    in these healthy young adults and they often
    live, work, and study in close proximity, and
    they are a frequently mobile population and,
  • Persons aged 25 through 64 years who have health
    conditions associated with higher risk of medical
    complications from influenza.

Source CDC
32
Swine Influenza A(H1N1) Face Mask and
Respirator Protection
Setting Persons not at increased risk of severe illness from influenza (Non-high risk persons) Persons at increased risk of severe illness from influenza (High-Risk Persons)
Community Community Community
No 2009 H1N1 in community Facemask/respirator not recommended Facemask/respirator not recommended
2009 H1N1 in community not crowded setting Facemask/respirator not recommended Facemask/respirator not recommended
2009 H1N1 in community crowded setting Facemask/respirator not recommended Avoid setting. If unavoidable, consider facemask or respirator
Home Home Home
Caregiver to person with influenza-like illness Facemask/respirator not recommended Avoid being caregiver. If unavoidable, use facemask or respirator
Other household members in home Facemask/respirator not recommended Facemask/respirator not recommended
Occupational (non-health care) Occupational (non-health care) Occupational (non-health care)
No 2009 H1N1 in community Facemask/respirator not recommended Facemask/respirator not recommended
2009 H1N1 in community Facemask/respirator not recommended but could be considered under certain circumstances Facemask/respirator not recommended but could be considered under certain circumstances
Occupational (health care) Occupational (health care) Occupational (health care)
Caring for persons with known, probable or suspected 2009 H1N1 or influenza-like illness Respirator Consider temporary reassignment. Respirator
Source CDC
33
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 non-quarantine measures that might serve
    to reduce contact between persons, such as,
    closing of schools or prohibiting large gatherings

Source CDC
34
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.

Source CDC
35
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.

Source CDC
36
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.

Source CDC
37
Summary
  • WHO raised the alert level to Phase 6 on June 11,
    2009
  • As of December 28, 2009, worldwide more than 208
    countries and overseas territories or communities
    have reported laboratory confirmed cases of
    pandemic influenza H1N1 2009, including at least
    13,000 deaths
  • Northern Hemisphere Overall disease activity has
    recently peaked.
  • Central and Eastern Europe, and in parts of West,
    Central, and South Asia Continued increases in
    influenza activity
  • United States and Canada Influenza activity
    continues to be geographically widespread but
    overall levels of influenza-like-illness has
    declined substantially
  • Approximately 53 of hospitalized cases in Canada
    had an underlying medical condition
  • Europe Widespread and active transmission
    continued to be observed throughout the continent
  • Overall pandemic influenza activity appears to
    have recently peaked across a majority of
    countries
  • Western and Central Asia Virus circulation
    remains active throughout the region, however
    disease trends remain variable
  • East Asia Influenza transmission remains active
    but appears to be declining overall
  • Central and South America and the Caribbean
    influenza transmission remains geographically
    widespread but overall disease activity has been
    declining or remains unchanged in most parts,
    except for in Barbados and Ecuador, were recent
    increases in respiratory diseases activity have
    been reported
  • Southern Hemisphere Sporadic cases of pandemic
    influenza continued to be reported without
    evidence of sustained community transmission.

38
Summary
  • In the US
  • Highest incidence of lab-confirmed cases reported
    among 5-24 years old
  • Highest hospitalization rate among 0-4 years old
  • Underlying health conditions confers high risk of
    complications and deaths
  • In Mexico
  • Majority of the cases reported in health young
    adults
  • 70 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
  • In EU
  • Majority of the cases reported in health young
    adults (20-29 years)
  • Globally
  • Number of deaths being reported is rising
  • Vaccine
  • Total Adverse Events 5.4 (0.3 fatal)
  • Sanofi Pasteur MedImmune vaccine recalled due
    to potency issues
  • Anti-virals (oseltamivir and zanamivir)
  • Oseltamivir resistance reported recently in
    immunocompromised patents

39
Conclusion/Recommendations
  • Past experience with pandemics have taught us
    that the second wave is worse than the first
    causing more deaths due to
  • Primary viral pneumonia, Acute Respiratory
    Distress Syndrome (ARDS), Secondary bacterial
    infections, particularly pneumonia
  • Fortunately compared to the past now we have
    vaccines, anti-virals and antibiotics (to treat
    secondary bacterial infections) rT-PCR based
    rapid diagnostic devices
  • This pandemic is milder than previously predicted
    with a case-fatality less than 1
  • At present most of the deaths due to the novel
    H1N1 strain has been reported from the Americas.
  • Disease seems to be affecting the healthy strata
    of the population based upon epidemiological data
  • Anecdotal data suggests that the number of deaths
    among the pediatric population has risen recently
    due to infection with the novel H1N1
  • Most of these deaths however have been reported
    in cases with underlying medical conditions
  • 60 years and above age group seems to show some
    protection against this strain suggesting past
    exposure and some immunity

40
Conclusion/Recommendations
  • Each locality/jurisdiction needs to
  • 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
  • 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
  • This novel H1N1 strain has survived high humidity
    or temperature and continued to spread during the
    summer months and will continue to spread and
    cause infection

41
Conclusion/Recommendations
  • School Closures
  • Preemptive school closures merely delay the
    spread of disease
  • Once schools reopen the disease transmits and
    spreads
  • Puts unbearable pressure on single-working
    parents and would be devastating to the economy
  • 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
  • Burden of Disease Mortality
  • Actual burden of the disease will be higher than
    the regular seasonal flu despite the availability
    of vaccine, antivirals and excellent public
    knowledge
  • With the variation in reporting it is very
    difficult to appreciate the total number of
    deaths
  • It is imperative to appreciate that
    times-have-changed
  • 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, vaccines,
    anti-virals, antibiotics and advancement in
    science and resources to produce countermeasures
    quickly

42
References
  • World Health Organization (WHO)
  • http//www.who.int/csr/disease/avian_influenza/en
    /
  • World Organization for Animal Health (OIE)
    http//www.oie.int/wahid-prod/public.php?
  • Centers for Disease Control Prevention (CDC)
    http//www.cdc.gov/flu/avian/index.htm
  • Chotani R. Just-in-time, H1N1 Influenza.
    Epidemiology Supercourse. December 2009.
  • El-Bushra H. Global and Regional Update on Human
    Pandemic Influenza A H1N1 2009. Cairo WHO/EMRO,
    2009
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