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IPFADublin2011-QSMAP
WHO views on Emerging Pathogens
Ana PadillaAna Padilla Blood Products and related BiologicalsBlood Products and related Biologicals
Quality Assurance and and Safety: Medicines Quality Assurance and and Safety: Medicines World Health OrganizationWorld Health Organization
IPFADublin2011-QSMAP
● "Emerging infectious diseases can be defined as infections that have newly appeared in a population or have existed but are rapidly increasing in incidence or geographic range. "
S.S. Morse. Factor in Emergence of infectious diseases. EID 1996.
Emerging Infectious Diseases: a definition
IPFADublin2011-QSMAP
Assessment criteria considered Assessment criteria considered
● Global health concern regarding the disease agent
● Incidence rapidly increasing; risks to increase in future
● Adaptability to unplanned urbanized environment
● Adequate surveillance or not to allow recognition
● Possibility of impact in health sectors and blood supply
● Infectious agent with actual or potential risk of transfusion transmission (asymptomatic blood phase)
● WHO collected information on prevalence and outbreaks available
IPFADublin2011-QSMAP
Dengue Fever Global Situation
IPFADublin2011-QSMAP
Dengue Virus
● Most rapidly spreading mosquito-borne viral disease
● Transmitted by Aedes mosquitoes
● Four virus serotypes (DEN-1, 2, 3, 4)
● Each serotype induces specific lifetime immunity
● All serotypes can cause severe and fatal disease
● Secondary infection with a different serotype increases the risk of more severe disease
IPFADublin2011-QSMAP
Average number of Dengue cases reported
to WHO per year
908 15497
122174
295554
479848
925896
1279668
1451083
0
200000
400000
600000
800000
1000000
1200000
1400000
1600000
55-59 60-69 70-79 80-89 90-99 00-07 2008 2009
Period or year
Nu
mb
er
of
ca
se
s
IPFADublin2011-QSMAP
IPFADublin2011-QSMAP N Engl J Med 2007;356:769-771
Aedes albopictus (Asian Tiger mosquito(
IPFADublin2011-QSMAP
● Up to 3.0 billion people live under threat of dengue
● with 50 million new infections
● and 24,000 deaths reported annually
● in over 100 countries
DENGUE IS GROSSLY UNDER REPORTED
Estimates of Dengue Disease Burden
*Asymptomatic infection increases risk of more severe disease with subsequent infection
IPFADublin2011-QSMAP
High number of cases unreported
“Iceberg” phenomenon: how much of it is visible?
UNREPORTED
REPORTED
IPFADublin2011-QSMAP
DENGUEDENGUE
VirusVirus
●More than one circulating virus serotype
●No effective ant-viral drug or vaccine
Vector
• High adaptability to unplanned urbanised environment
• Seasonal, temperature & vapour pressure influence
• Viability of desiccated eggs upon rehydration
Host
●Population density
●Population mobility
●Health- seeking behaviour
●Rate of sub-clinical infection
●Herd immunity
Dengue: a Multifactorial Disease
IPFADublin2011-QSMAP
Drivers of epidemic dengue
●Demographic Changes● Population growth
● Urbanization
●Modern Transportation● Increased movement of people and goods
●Changes in Public Health Policy ● Lack of Vector control
●Microbial Adaptation
IPFADublin2011-QSMAP
Human outbreak
0
10
20
30
40
50
60
70
80
90
-20 -15 -10 -5 0 5 10 15 20 25 30 35 40
Nu
mb
er o
f C
ases
TIME
Dengue fever outbreak alert and response
Humanoutbreak
NB: Yellow areas represent cases that can be prevented with control operationsMosquito population
ForecastingReadiness
Early Detection
Rapid Response
Control Opportunity
IPFADublin2011-QSMAP
Coordination● Activate established multisectoral dengue action committee
● Activate formalized emergency response plan with all stakeholders from local government (blood national programmes should be involved), public and private sectors, professional and community representatives
● Partnership with media and information to the community and professional groups about the control procedures used by the responsible authorities in their jurisdiction
Social mobilization
● Promote practices that lead to source reduction, personal protection and health care seeking behaviour
● Restrict practices that promote transmission and source of infection
1: Strategy to CONTROL dengue outbreak
IPFADublin2011-QSMAP
Health Care● Ensure appropriate triage, patient care and infection control at all
levels of the health sector- (blood programmes should be involved)● Establish active surveillance system
Identify new cases and follow-up clinical complications Stop human source of infection and link with entomological
surveillance
Vector control● Implement appropriate vector control program based on
entomological surveys to reduce ongoing transmission in outbreak areas, prevent transmission in dengue free areas and stop transmission in areas with sporadic cases
2. Strategy to CONTROL Dengue outbreak
IPFADublin2011-QSMAP
Dengue Guidelines 2009
http://www.who.int/denguecontrol/en
IPFADublin2011-QSMAP
Diagnostic tests according their accessibility and their confidence
IPFADublin2011-QSMAP
Chagas Disease Global Situation
IPFADublin2011-QSMAP
IPFADublin2011-QSMAP
Migration Flows from Latin America Chagas Disease
Schm
unis G; M
em Inst O
swaldo C
ruz , 2007
IPFADublin2011-QSMAP
Update of the world map: Chagas disease (Trypanosoma cruzi)W
HO
NT
D R
eport 2010
IPFADublin2011-QSMAP
0 10 20 30
WHO 1960
WHO 1976
WHO 1981
PAHO 1984
Walsh 1984
WHO 1985
WHO 1990
Schmunis 1998
World Bank/DCPP 2006
PAHO 1994
millions
Chagas diseaseEstimated prevalence by year
IPFADublin2011-QSMAP
AcuteAcutephasephase
Chronic cardiac Chronic cardiac formform
Chronic phaseChronic phaseInitial indeterminate formInitial indeterminate form
Severe cardiopathySevere cardiopathyMild cardiopathyMild cardiopathy
Permanent Permanent indeterminateindeterminate
formform
90%
60%30%
Clinical evolution of Chagas disease
15%15%
Digestive formDigestive form
10%
IPFADublin2011-QSMAP
Epidemiological information update - Europe
Distribution of cases of T. cruzi infection in Europe by country, and reported transmission among the European population
(data reported to WHO as of Dec 2009)
IPFADublin2011-QSMAP
Stop transmission: blood transfusion,
organ transplantation,…
Patient care: diagnosis & treatment
of vertical transmission, acute and chronic
cases
Reduction of Chagas disease
burden
The two-pillar strategy
Global epidemiological
surveillance
Reporting in the next 65 WHA (2 years period)
Chagas disease: control and elimination (WHAResolution 63.20, May 2010)
IPFADublin2011-QSMAP
WHO International Biological Reference Preparations
for Chagas Disease Diagnostic Tests
• To provide a tool for comparison of results between different assays (biological measurement)
• To support development of improved diagnostic and blood screening tests and convergence of international regulations
IPFADublin2011-QSMAP
WHO event risk management flow chartWHO event risk management flow chartIdentify, Assess, Assist, InformIdentify, Assess, Assist, Inform
States PartiesWHO and UN
Others sources
Event risk assessment
Di ssemi nate
i nf or mati on
Verification
Initial screenin
g & triage
Informal/Unofficial
information
Formal reports
Other partners
Assist Respond
other technical partners
and
Initial sources of
information - EBS
IPFADublin2011-QSMAP
http://www.who.int/neglected_diseases/en/
IPFADublin2011-QSMAP
http://www.who.int/neglected_diseases/en/
IPFADublin2011-QSMAP
Early warning systemsEarly warning systems Event-based surveillance (EBS)Event-based surveillance (EBS)
A process for all hazards: Organised and rapid capture of information about events that are a potential risk to public health Events related to the occurrence of disease in humans as
recognised by health professionals and other key informants in the country (including the media) Unusual disease patterns (clusters or atypical cases)
Unexpected deaths
Events related to potential exposure for humans Events related to disease and deaths in animals,
contaminated/adulterated food, environmental hazards including chemical and radionuclear events
[email protected]@who.int
IPFADublin2011-QSMAP
EBS for blood safety issues?EBS for blood safety issues?
● What would be useful signal events?
● Are there any key words that could be used for EBS?
● Any new or emerging diseases – to be assessed for blood safety implications?
[email protected]@who.int
IPFADublin2011-QSMAP
Thanks to my colleagues in WHO:
Dengue Haemorrhagic fever
Dr Raman VelayudhanDr Raman VelayudhanControl of Neglected Tropical DiseasesControl of Neglected Tropical Diseases http://www.who.int/neglected_diseases/en/http://www.who.int/neglected_diseases/en/
Dr Renu Drager-DayalDr Renu Drager-DayalGlobal Alert and ResponseGlobal Alert and Response
http://www.who.int/csr/en/ http://www.who.int/csr/en/
Chagas Disease Dr Pedro Albajar ViñasDr Pedro Albajar Viñas Control of Neglected Tropical DiseasesControl of Neglected Tropical Diseases http://www.who.int/neglected_diseases/en/http://www.who.int/neglected_diseases/en/
Events based surveillance Dr Angela MerianosDr Angela MerianosAlert and Response OperationsAlert and Response OperationsGlobal Alert and ResponseGlobal Alert and Response
[email protected]@who.int