Addressing Emerging Pandemic Threats

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Addressing Emerging Pandemic Threats:
Lessons
from theand
PastLessons
10 Years
Observations
from the Past 100 Years
Andrew Clements, Ph. D.
USAID, Bureau for Global Health
7 March 2014
Emerging Threats Program
Background: Existing vs. New Public Health Threats
Existing Public Health Threats
Examples
New Public Health Threats
Affected
Areas
HIV/AIDS, TB, malaria, preventable pH1N1, H5N1, and H7N9 influenza;
SARS and MERS coronavirus;
childhood diseases, ARIs, DDs,
Nipah virus
NTDs, under-nutrition, chronic
diseases
very low (<1000 cases annually),
high (millions of cases annually)
but case fatality rates 10-70%
often geographically contained
geographically dispersed
(country, sub-region)
(global, regional)
Diagnostics
yes
no or limited distribution
Interventions
yes
no
Program
focus
scaling up interventions;
building capacity
gathering evidence for interventions;
building capacity
Disease burden
Budget, staffing, insufficient in many countries to go
to scale; substantial international/
training,
donor assistance for scale-up
commodities
Emerging Threats Program
insufficient in many countries to
gather evidence; very limited
international/donor assistance
Challenge: Mobilizing Resources for New Threats
• Relatively low incidence
• Immediate health threats
higher priority than potential
future threats
• Frequent warnings of new
threats met with skepticism
Difficult to mobilize resources
(country level and international/donor level) to:
• gather evidence
• develop/distribute diagnostics
• respond while problem still
manageable
The sky is
falling !
Emerging Threats Program
Challenges: Understanding New Threats
• Standard case definitions
and reporting procedures
usually lacking
• Health care staff and
communities generally not
sensitized to signs and
symptoms
• Difficult to determine risk
factors with only tens or
hundreds of cases spread
out over several years
Emerging Threats Program
• Very difficult to design
interventions
• Interventions will most
likely be non-biomedical
(e.g. policy, behavioral)
-
Unless current medicines/
vaccines are effective,
generally not enough time to
develop new
medicines/vaccines
-
Even if current medicines/
vaccines are effective,
generally not sufficient
quantities for need,
especially for a pandemic
Gathering Evidence for Interventions: A Classic Model
2
Map of cholera cases in Soho, London (1858)
Intervention =
remove pump
handle
Dr. John Snow
Emerging Threats Program
Broad St. pump
Gathering Evidence on New Public Health Threats
Two parallel approaches
1. Study past pandemics (very rare; only 7 since 1900)
2. Study emerging public health threats (rare, but hundreds of
events since 1940s)
Key questions include:
• Where, how did they start?
• What impact did they have?
• Why were these microbes successful?
• What interventions (if any) worked?
Emerging Threats Program
Observations on Pandemics
Relatively low mortality (<10 million)
Relatively
low economic
impact
Relatively
high economic
impact
H2N2 flu
(1957-1958)
H3N2 flu
(1968-1969)
7th cholera pandemic*
(1961-present)
Relatively high mortality (>10 million)
pH1N1 flu
(2009-2010)
SARS-CoV
(2002-2003)
H1N1 flu
(1918-1919)
HIV/AIDS
(~1920-present)
Observations:
• Origin: Asia (4), Africa (1), Americas (1), unknown (1)
• Source: animals (6), environment (1)
• Type of microbe: virus (6), bacteria (1)
• Direct human-to-human transmission (6)
• Some acute (5), others protracted (2)
• Potential for very high mortality
• Low mortality does not equal low economic impact
• Impact can vary considerably across countries**
• Only one (SARS) was contained by (non-biomedical) interventions***
Emerging Threats Program
Source: WHO; * since 1800. ** e.g. average mortality rate for
1918 flu ranged from 0.2%-20% in part because of income level;
*** infection prevention and control in hospitals
Observations on Other Emerging Public Health Threats
• Many caused by viruses from animals such as bats,
rodents, primates*^; livestock may amplify viruses
• Disease spillover associated with all regions, but
some areas are “hot spots” due to favorable
conditions such as specific human activities*
•
Diseases emerging from wildlife
New diseases can have significant impact**
mortality usually low, but economic impact can be significant,
e.g. >$200 billion in direct and indirect costs over past decade
Diseases emerging from livestock
• Most human infections due to animal-to-human transmission; some
human-to-human transmission possible, but not efficient
• Cross-sectoral approaches can improve detection/response
• In some cases, non-biomedical interventions (changes in farming and
livestock marketing; infection prevention and control in hospitals) have
reduced amplification/spread among animals and among people
Emerging Threats Program
* Global Trends in Emerging Infectious Diseases, Jones, et al., 2008,
Nature, 451:990-994; ** People, Pathogens and Our Planet – Volume 1:
Towards a One Health Approach for Controlling Zoonotic Diseases, World
Bank. ^ USAID PREDICT project
Spillover, Amplification, and Spread
further
amplification
and spread
No further
transmission
spillover
from wild
animals to
people
human to
human
transmission
No further
transmission
No further
transmission
spillover from
livestock to
people
source
No further
transmission
spillover from
wild animals
to livestock
amplification
Emerging Threats Program
No further
transmission
Minimizing Spillover, Amplification, and Spread
Limited
interventions
spillover
from wild
animals to
people
Good hospital
interventions;
some community
interventions
human to
human
transmission
X
Good farm and spillover from
market
interventions livestock to
source
people
spillover from
X
Good farm and wild animals
market
interventions to livestock
source
Emerging Threats Program
Recent Emergence of Select “New” Viruses*
Already spreading
400
efficiently from
person to person
when first detected 350
Cumulative
number of
reported
human
cases
(confirmed)
At least
17,000 cases
after 2 months
pH1N1 flu
(Apr 09)
At least
1,037 cases
after 4 months
Solid lines = efficient human-to-human spread
Dotted lines = primarily animal-to-human spread
Dashed lines = both animal-to-human and human-to human spread
SARS-CoV
(Nov 02)
H7N9 flu
(Feb 13)
300
250
200
Mostly animal-tohuman transmission
with limited human-tohuman spread
MERS-CoV
(Mar 12)
150
100
H5N1 flu
(Nov 03)
50
0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
Months after first human case
* Based on symptom onset data from WHO (H5N1, H7N9, MERS-CoV) through 3/5/14, WHO case counts (H1N1), and Molecular Evolution
of the SARS Coronavirus During the Course of the SARS Epidemic in China, Science, 12 March 2004, 303, pp. 1666-1669. ^ November 2003
used for H5N1 since this was the beginning of this virus’ continued spillover into human populations in multiple countries.
Emerging Threats Program
One Example: Reducing Spillover of New Threats
120
Global H5N1 human cases by year
80
40
*
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
0
3600
2400
1200
H5N1
Global H5N1 poultry outbreaks by year
Interventions:
• Rapid detection
• Culling infected birds
• Poultry vaccination
• Farm/market biosecurity
*
*
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
0
Emerging Threats Program
Lesson learned: for
some public health
threats, the “pump
handle” may be an
animal
Sources: FAO, OIE, WHO; * = data not complete
What is the Future Forecast for New Threats?
• Spillover of animal diseases into human populations
expected to continue; many diseases benign, some serious
• Rates of spillover, amplification, and spread will increase
over time since drivers (human and animal population size
and density, land use change, etc.) will likely continue to
increase
• However, with improved interventions and investments in
their proper application, rates of spillover, amplification,
and spread could be decreased
• Existing interventions (farm/market biosecurity; infection prevention
and control in hospitals) need wider application
• Need other complementary interventions, e.g. limit spillover of
diseases from wildlife to people
Emerging Threats Program
More People = More Opportunities for Disease Spillover
All driven by increasing human population
Rapidly
increasing
Increasing Increasing Increasing
Increasing
domestic + crop
+human
+ natural =animal-human
population
animal
production resource
Increasing
human
population
production
extraction
(e.g. timber,
minerals, oil/gas)
contact and
spillover rate
Host animals
for influenza
viruses
World Meat Production by Type, 1961-2005 (FAO)
Percent increase
+320%
+700%
+132%
+1950%
+117%
Emerging Threats Program
Year
Opportunities for Disease Spillover from Animals
Which contribute most
to disease spillover?
Bush-meat hunting
Live animal markets
Collecting animal waste
Which interventions
are most effective?
Pets
Wildlife and livestock farms
Emerging Threats Program
Extractive industry/
Land use change
Human Activities Disrupting Animal Habitats
From History
the film Contagion,
Warner
Bros.
Pictures
shows2011,
again
and
again
how nature points out the folly of men
From “Godzilla” by Blue Öyster Cult (1977)
Emerging Threats Program
Human Activities Attracting Wildlife
Emerging Threats Program
Source: Dr. Steve Luby, Stanford University
Opportunities for Disease Amplification
Which contribute most to
disease amplification?
Roving flocks
Which interventions are
most effective?
Mixing species on farm
Mixing species in market
Emerging Threats Program
“Factory” farms
Hunan,
Yunnan
Guangxi
Opportunities
for&Disease
Spread (via Trade, Travel)
Informal poultry trade in Asia
Which contribute most
to disease spread?
Source:
http://www.thestar.com.my/story.aspx/?file=%2f2009%2f8%2f10%2fstarprobe%2f4369565
Source: FAO commissioned cross-border study reports
Pet fish trade out of South America
Air travel
Which interventions
are most effective?
Source: http://spatial.ly/2013/05/great-world-flight-paths-map/
Emerging Threats Program
Source:
http://wwf.panda.org/what_we_do/where_we_work/amazon/vision_amazon/models/natural_resources_manage
ment_amazon/aquarium_trade_amazon_rainforest/
First North America H5N1 bird flu death confirmed in Canada
8 January 2014 Last updated at 17:35 ET
BBC
Canadian health officials have confirmed the first known fatal case of the
H5N1 avian influenza strain in North America. Canadian Health Minister
Rona Ambrose said the deceased person was an Alberta resident who had
recently travelled to Beijing.
Calling the death an "isolated case", Ms Ambrose said the risk to the
general population was low. Ten people have died in Alberta this season
from swine flu, or H1N1. H5N1 infects the lower respiratory tract deep in
the lung, where it can cause deadly pneumonia.
In the latest incident, the infected person first showed symptoms of the
flu on an Air Canada flight from Beijing to Vancouver on 27 December,
officials said. The passenger continued on to Edmonton and on 1 January
was admitted to hospital where they died two days later.
Emerging Threats Program
Next Steps for Addressing New Public Health Threats
• Strengthen developing country protocols, platforms,
and capacities for cross-sectoral, rapid disease
detection/response  these will be used for
responding to new threats
• Understand which public health threats are most
likely to spillover from animals to people
• Investigate (in advance) mechanisms for spillover of
animal disease to people
• Develop interventions and response plans, monitor,
and revise as needed
Emerging Threats Program
Recent Detection of Avian Influenza Viruses in Asia
June 2013-February 2014
Virus sub-type
H5N1 HPAI*
H5N2 HPAI
H5N8 HPAI
H6N1 AI^
H7N2 HPAI
H7N9 AI
H9N2 AI
H10N8 AI
Sources: OIE, WHO; * Highly-Pathogenic Avian Influenza; ^ Avian Influenza. Hosts for each of the influenza
virus sub-types are indicated as follows: humans ( ); poultry (
); wild birds ( ). Dots shows the
approximate location where an influenza virus sub-type was detected in any of the hosts.
Emerging Threats Program
= not detected in
people prior to 2013
Detection of Specific Zoonotic Viruses that have
Potential to Spread within Human Populations*
Nov 2012-Oct 2013
Nov 2013-Oct 2014
Imported
from China
= H5N1 highly-pathogenic avian influenza (poultry, wild birds, or humans
= H7N9 low-pathogenic avian influenza (poultry, wild birds, or humans)
= other novel avian influenzas such as H6N1 and H10N8 (humans)
= other highly-pathogenic avian influenza H5, H7, or H9 avian influenza (poultry, wild birds) and/or other low-pathogenic H5, H7, or H9 (humans)
= H1N1v, H1N2v, and H3N2v swine influenza (humans)
= Ebola (humans)
= Marburg (humans)
= Nipah (humans)
= Middle East Respiratory Syndrome-Coronavirus (humans)
Sources = OIE, WHO, CDC, Ministry of Agriculture/FAO (Egypt, Indonesia), and IEDCR (Bangladesh) reports between 11/1/12 and 3/14/14. * = All of these viruses are capable of
infecting people and human populations likely do not have wide-spread immunity to them; at present, human-to-human transmission appears to be limited. While these reports reflect
known infections with these viruses, there may be additional viral circulation in these and other countries that is not detected due to limitations in surveillance and/or detection.
= countries (including northeastern Brazil, southeastern China, and most of Indonesia) using USAID funding between FY2012 and
Emerging
FY2014 for surveillance and response
to avian influenzaThreats
and/or otherProgram
emerging pandemic threats.
Mapping Viral Diversity in “Hot Spot” Regions
PREDICT Project:
Animal and human samples being tested for 20 viral families known to cause human disease including
Coronaviruses, Ebola, Influenza, Marburg, Nipah. Over 250 novel viruses have been detected so far.
Emerging Threats Program
Building the Foundation for Action
Existing
public
health
threats
Mostly done
Mostly done
Problem
identification,
gathering
evidence
Developing/
testing
interventions
In process
Scaling up
interventions
Strengthening capacity
You
are
here
New
public
health
threats
In process
Just beginning
Problem
identification,
gathering
evidence
Developing/
testing
interventions
Strengthening capacity
You
are
here
Emerging Threats Program
Not started
Scaling up
interventions
Time
“One Health” Approach
Because of the role of animals in the spillover and
amplification of Emerging Public Health Threats,
prevention, surveillance, detection, response and
research efforts along with training need to operate
in multiple sectors
Public
Health
The “One Health” concept
recognizes that the health of
humans is connected to the
health of animals and the
environment.
“One
Health”
Animal
Health
Emerging Threats Program
Environmental
Health
Source: CDC http://www.cdc.gov/onehealth/
Existing One Health Capacity Limited
• Limited capacity for dealing with old and new disease
threats for both animals and people:
 Limitations in disease detection/response capacity, health care services,
data for policy, staff, budgets
 Insufficient stockpile of biomedical measures (e.g. vaccines, medicines)
• Limited capacity to predict disease emergence
 Some understanding on where, how, and why diseases emerge, but
more specificity needed for prevention and containment
• Lack of effective coordination
 across society (e.g. government, military, civil society, private sector)
 across sectors (e.g. public health, animal health, environment)
Emerging Threats Program
USAID Pandemic Influenza & Other Emerging Threats
Activity areas:
Avian
Influenza
Pandemic
Preparedness
Current activities
Past activities
Emerging Threats Program
Other Emerging
Threats
PIOET Accomplishments (2005-2014): New Threats
1. Decreased H5N1 threat
– Faster detection and containment
– Fewer countries affected
2. Enhanced pandemic preparedness
– 30 countries established national coordinating bodies for preparedness
– 25 countries developed “first order” pandemic preparedness plans
– Military authorities in 32 countries developed “civ:mil” preparedness
response plans
3. Improved infectious disease detection
– Detection of routine infectious diseases
– Surveillance and detection of microbes with pandemic potential
– Improved understanding of conditions that favor disease emergence/spread
4. Strengthened capacity
– Pre-service training (One Health)
– In-service training (public health, animal health): lab, surveillance, epi, etc.
* Coordinated with CDC and WHO; ^ coordinated with FAO
Emerging Threats Program
PIOET Accomplishments (2005-2014) continued
5. Rapidly used PIOET platforms and expertise to
address new threats:
•
H1N1 influenza pandemic (2009-2010)*
–
–
–
•
MERS-coronavirus (2012-2014)*
–
–
•
detailed technical and logistics experts to WHO to assist in planning
distribution of vaccine and ancillary equipment
deployed >70 million doses of H1N1 pandemic vaccine (including U.S.
donation) and injection equipment to >60 countries
upgraded H1N1 surveillance and laboratory capacities in 26 countries in
Africa and Latin America
genetic sequence comparison used to target surveillance
surveillance and lab protocols used to identify animal source
H7N9 avian influenza (2013-2014)*^
–
surveillance and lab protocols used to identify animal source and other
potential threats circulating in animals
* Coordinated with CDC and WHO; ^ coordinated with FAO
Emerging Threats Program
H7N9
(2013)
MERS-CoV
(2012)
H1N1
(2009)
H5N1
(2005)
SARS-CoV
(2002)
Animal and human
infectious disease
programs
Global Health Security
“To stop disease that spreads across borders, we must strengthen our systems of
public health…. And we must come together to prevent, detect, and fight every
kind of biological danger – whether it is a pandemic like H1N1, a terrorist threat,
or a treatable disease.
--President Obama, UNGA, September 22, 2011
• White House Global Health Security Vision – “to
prevent, detect, and respond to biological threats,
regardless of cause”
• Provides a new and important strategic framework for
“re-visioning” our rationale for action and opportunities for
broadening our partnerships
Emerging Threats Program
USAID Goal Under Global Health Security
As the “Development” arm of the USG Global
Health Security Framework, USAID will launch its
Emerging Pandemic Threats Program (ver. 2) in
October 2014 to:
mitigate the impact of novel high consequence pathogens arising
from animals through a suite of “One Health” investments
targeted at the animal-human interface that enable
•
early detection of new disease threats*;
•
effective control through enhanced national-level preparedness*;
•
reduction of risk of disease emergence by minimizing practices
and behaviors that trigger spillover and spread of new pathogens*
Emerging Threats Program
* Building on developing-country programs to address
infectious diseases in animals and people.
Further reading
• Origins of AIDS, Jacques Pepin, 2011
• Global Trends in Emerging Infectious Diseases,
Jones et al., 2008, Nature, 451:990-994
• The Great Influenza, John Barry, 2004
• The Coming Plague, Laurie Garrett, 1994
• Guns, Germs, and Steel, Jared Diamond, 1997
Emerging Threats Program
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