Surveillance of emerging diseases and networks

Surveillance of emerging diseases and networks: “the whole is (still) more than its part”

Dr Jean-Jacques BERNATAS, MD (Montpellier), MSc (DEA Paris 6)Public Health Specialist

Senior medical advisor, International SOS

Jakarta, Indonesia - 17th December 2010 - Universitas Indonesia, Center for Research and Integrated Development Tropical Health and Infectious Diseases

Plan

Introduction Definition and concepts Examples Rapid assessment

Introduction -1

Health surveillance is not a new deal: 14th century: Republic of Venice, Italy. Surveillance of

bubonic plague on ships before disembarkation 1878, USA: congress authorized Public Health

Services to collect data for detecting “pestilential diseases” and undertake quarantine measures

Worldwide smallpox eradication in the 1970’s succeeded because of an active surveillance of the new cases

1980’s: introduction of computers improved data aggregation and analysis

1990’s to 2000’s web revolution

Introduction -2

SARS epidemic in 2003 demonstrated the efficiency of a global surveillance network: GOARN/WHO (created in 2000), and also our global fragility facing new pathogens

Core of the IHR 2005 and PHEIC At the national level: US-CDC (USA), InVS (France), … At regional level: ECDC (Europe), MDBS (Mekong

Region), …

Health-related Events under Surveillance

Detection Decision Notification Action

International Health Regulations (IHR) 2005 decisioninstrument (simplified from annex 2 of IHR).

Introduction -3

Definitions and concepts

Surveillance Emerging disease Network Systems theory

Definitions and concepts: Surveillance (1)

Operational concept: “… process that is used to collect, manage, analyze, interpret and report information about the status of specific diseases or their antecedents in a specific population “ (J. W. Buehler in “Modern Epidemiology”, Rothman &al.)

Objectives: Descriptive epidemiology of health

problems TIME-PLACE-PERSONS Monitoring, planning PH interventions:

Evaluation Education and policy

(Research?): they nourish each other

Definitions and concepts: Surveillance (2)

Attributes of surveillance (US CDC, 2001): Timeliness: depends on the objective of the system. TB:

quarterly reports; Influenza: weekly reports; Ebola or other hemorrhagic fever: hours.

Sensitivity: ability to detect an event at interest Predictive value: are reported cases really cases? Does it

measure what it aims to measure. Representativeness: /target population. Data quality: accuracy, completeness. Simplicity: time, money wasting; error risk mitigation. Flexibility: adaptation to needs and circumstances. Acceptability: willing to participate, motivation, perreniality

Definitions and concepts:Emerging disease

Emergence of a new human pathogen: Emergence of human pathogenicity in

commensal human species (S. Aureus MRSA)

Interspecies transfer from animals to human: A(H1N1)so, A(H5N1), HIV, SARS-CoronaV

Presence of a known human pathogen in new areas (West-Nile in NYC in 1999 then in all US; chikungunya in Indian ocean) or dramatic and sudden extension of pre existing pathogen (DF in South-East Asia, )

Emergence of knowledge: identification of a new pathogen in specific human diseases (HCV in Egypt, HHV8 and Kaposi sarcoma in Africa):

1918 “Spanish flu”

Definitions and concepts:Emerging disease

Human-animal contacts

Virus-to-human adaptation: influenza viruses

Virus-to-vector adaptation: chikungunya (Reunion Island, 2005: Aedes aegyptiAedes albopictus)

Climate change

Movements of population: short-term (travel) vs. long-term (migration) perspectives

Density of population, both human and animal (animal husbandry)

Weiss RA, Nature Medicine, 2004

Definitions and concepts:Network (“jaringan”?) Nodes and vertices (vertex/vertices):

Topology: description of the relations between nodes

Other properties: connectivity, directed vs. non directed, eccentricity, radius, diameter, coloring graph

Why?!

Definitions and concepts:Network (“jaringan”?) -2

Method for modeling infectious diseases based on contacts patterns. (How a rumor spread all over the world or the “Facebook modeling” …)

Fraser, PNAS, 2004

(Christian, CID, 2004)

Stochastic models in opposition with deterministic models (famous “R0, S/I/R and differential equations)

Definitions and concepts:System theory Interacting entities Primary interactions: positive and negative

feedback Emerging properties and science of

complexity (Ilya Prigogine). Broader framework to conceptualize the

interactions in all organized systems, including biological and epidemiological ones

Distributed systems vs. centralized systems

Examples

SISEA/Pasteur

MDBS

TB

Christian, CID, 2004

Examples: SISEA/Pasteur -1 Objective: to contribute to the improvement of the detection and handling of

epidemic situations in the region, with 3 components: Strengthen national reference laboratories Strengthen epidemic detection Strengthen outbreak response capacities

at national and regional levels, in collaboration with WHO Nodes: healthcare facilities in Vietnam, Laos, China and Cambodia among

Pasteur Institutes International Network in South-East Asia; national health authorities

Vertices: monthly reports to national health authorities, and regular workshops.

Findings: Knowledge of respiratory viruses pattern circulation in SEA, Emergence of knowledge: meiloidiosis in Cambodia, Alert and disease control: japanese encephalitis in South

Vietnam, Capacity building and strengthening of national surveillance

institution: skills and procedures

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Network .... and sub-network

International Pasteur Institutes Network – 32 members on 5 continents

Examples: SISEA/Pasteur -2NODES

= MODEL

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Network of laboratories & hospital-based sentinel sites

IPS- pediatric hospital of Nanxiang

- Guangxi CDCNIHE - Provincial Hospital of Hai Duong- District hospital of Cam Giang

- 19 communes

NCLE- Setthathirath Hospital, Vientiane

- Mahosot Hospital, Vientiane,- Friendship hospital, Vientiane,- Luanprabang regional hospital

IPNT- Provincial Hospital of Binh Dinh

- District Hospital of Phu Cat

IP HCMC- Ben Tre provincial hospital

- Cu Lao Minh district hospitalIP Cambodia- Provincial hospital of Takkeo

- Provincial hospital of Kampong Cham

Examples: SISEA/Pasteur -3

Vertices: case definition of SARI adopted in Vietnam and used to report the cases:

≤ 05 y.o. > 05 y.o.

Cough or breathing difficultyAND

One of the following:TachypneaChest indrawingGeneral signs of danger

Onset of symptoms up to and including 7 days

Fever ≥ 38o C (or history of fever) AND

Cough OR sore throat OR breathing difficultyAND

One of the following:≥ 30 respirations/minNew infiltrate on chest X-rayInability to speak full sentencesUse of accessory respiratory musclesArterial O2 saturation ≤ 92% on air (no oxygen therapy)

Onset of symptoms ≤ 7 days



Findings/outcomes: Improving surveillance through a better knowledge of

some EIDs: ARI&AES. 2 examples: Improving surveillance in Lao PDR Improving surveillance in Cambodia:

Improving surveillance in Lao PDR:

• Technical assistance in microbiology and epidemiology

• ALRI surveillance, complementary approach to the other surveillance system implemented (EWORS, EWARN, ILI):

• ILI: 2007 to 2008 : 507 ILI specimens collected → 142 (28 %) +ve for IAV and IBV, 2009 : 533 specimens collected → 139 (26 %) +ve for Influenza IAV and IVB.

• ALRI: Jul 08 to Oct 09: 222 specimens collected → 26(11.7%) +ve for IAV and IVB; 24 sputum specimens collected for bacteriology testing: 11(45.8%) +ve: S. pneumonia, H. influenza, S. aureus, P. aeruginosa, K. pneumonia (+ C. albicans)

• Contribution to ILI surveillance• Strenghtening virology, bacteriology, epidemiology capacities• Implementing a new sentinel site in Luanprabang

Influenza A,B11%

Enterovirus9%

HMPV1%

Para influenza virus4%

Mixed2%

Negative73%

ALRI Virology tested, 2009N=139


Improving surveillance in Cambodia – 1 (Vong S and al.):Implementation of the ALRI surveillance activities in April,2007: on Nov 2009, 3177patients enrolled. In depth clinical classification and data validation (Pr. Mayaud andal., Paris).

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Pneumonia Pleural infections

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Viro and bacterio : # positive results / # samples tested (%)

BK : # positive / # cases (%)



Findings/outcomes: Capacity strenghtening

Equipment, consumables HR Network integration and partnerships

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International Short Course in Biostatistics - REDI centre - Singapore, November 9-13, 2009.

Capacity strengthening and epidemiology

24 trainees/12 from SISEA and 12 from Indonesia

Daily and final evaluation; very good input from SISEA trainees

Very good perception by the trainees

New ties with professionals coming from Indonesia, and Singapore

High quality of the collaboration with REDI and NUS, who are demanding for other collaboration in training


Examples: MDBS (Mekong Basin Disease Surveillance) -1 Objective:

“to strengthen national and Mekong sub-regional capabilities in disease surveillance and response to outbreaks of priority diseases, in order that they can be effectively controlled.”

Nodes: healthcare facilities involved in cross-boarder activities

Vertices: weekly reports, training sessions, workshops

Findings: improved skills and commitment regarding infectious diseases in this area;

Examples: MDBS (Mekong Basin Disease Surveillance) -2

NODES

Examples: MDBS (Mekong Basin Disease Surveillance) -3 VERTICES

Examples: MDBS (Mekong Basin Disease Surveillance) -4

FINDINGS

Examples: TB -1

Objective: integrative part of DOTS Definition: DOTS strategy= Directly Observed Treatment Short-

course strategy sustained political commitment uninterrupted supply of quality-assured drugs access to quality-assured sputum microscopy standardized short-course chemotherapy including direct

observation of the treatment at least during the intensive phase Recording and reporting system standardized information

system enabling outcome assessment objective of the information system:

Activities evaluation Burden disease: reported smear+ cases, prevalence of smear +

pulmonary cases (prevalence survey), tuberculin survey And also: HIV co-infections, and drug resistance monitoring

(laboratories network)

Nodes: National level: local/regional TB centers; TB laboratories International level= NTP

Vertices: Standardized quarterly reports: case report and treatment

outcomes Laboratory quality control activities and surveillance of

sensitivity Anti TB drugs management &supply

Is a centralized system:

Examples: TB -2

Findings: Monitoring NTP at the global, regional and

national level. burden of disease estimation advocacy for

appropriate funding and policy (Re-)emerging diseases: MDR- and XDR-TB

help to adapt and monitor the response Triggers operational research: DOTS

evaluation and implementation according to specific context and constrains

Examples: TB -3

Rapid assessment

SWOT: Strengths Weaknesses Opportunities Threats

Rapid assessment:Strengths Distributed systems: “filter-effect”, improving the sensitivity and

specificity: A weak signal will be tested through other centres/nodes:

if confirmed, then amplification= sensitivity ( true +ves) +ve feedback

If not confirmed, then attenuation= specificity ( false –ves) -ve feedback

Multiple identical weak signals will sum in a strong signal (noise reduction)

Needs a dense network covering the area at interest

Feed the curiosity (scientific) and develop the exchanges: techniques, procedures, quality control,

Extend the size sample to give more consistency to the findings

Rapid assessment:Weaknesses

1- Quality of the system: ex. Lack of completeness:

Rapid assessment:Weaknesses

2- Appropriate use of data for a comprehensive and coordinated response in due-time:

Cross boarder actions not easy to set up: political and cultural concerns

Continuity/long-term= sustainability Same data may be interpreted differently by the partners,

and may trigger different responses.

Rapid assessment:Opportunities IT development: from ancient paper register (TB register) era to

web-based reporting system (TB, MDBS)

Political and economical development, international cooperation, necessary in our global village: countries have mutual advantages to cooperate, both developed and developing countries

“Public health emergency of international concern” (PHEIC, IHR 2005): increasing global threats (SARS, AI, SI, bioterrorism) and global awareness improved fund raising

Progress in knowledge (molecular biology) forces us to imagine new possibilities and increases awareness on the extraordinary adaptability of the human pathogens to our weapons: objective tends to cooperate rather than to eradicate

Rapid assessment:Threats Multiplication of networks not consistently

interconnected: conflictual information, adverse effect in term of PH action

Political and/or economical consequences: is it possible that neighboring adverse countries share fully sensitive information (Ex. North Korea/South Korea, Myanmar/Thailand, China, Japan, …) limitation of the global world?

Sharing biological material: whom do the strains collected belong to?

Conclusions & prospects -1

The whole is more than its part: TB control NP success is to some extend due to a strong and

simple interconnected information system Quick response rely on a dense and fluid network: SRAS

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Adding vertices to a network: Multiplies the number of interactions Increases sensitivity and sensibility

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Timeliness, accuracy and adaptability to correct quickly what Science bet before A(H1N1)sw-o regarding a possible pandemic:

Conclusions & prospects -2

References

Modern Infectious Epidemiology, 2nd Ed. Johan Giesecke. 2002, Arnold

Modern Epidemiology, 3rd Ed. KJ Rothman, S Greensland, TL Lash. 2008, Lipicott Williams & Wlkins

IHR 2005, WHO Management of Tuberculosis: A Guide to the Essentials of

Good Clinical Practice , N. Aït-Khaled, E. Alarcón, R. Armengol et al. 6th Ed. International Union Against Tuberculosis and Lung Disease (The Union), 2010.

MDBS project, http://www.mbdsoffice.com/pdf/MBDS_Presentation_Dec2009.pdf

Public Health Surveillance: A Historical Review with a Focus on HIV/AIDS. Michael A. Stoto. RAND Health, 2003. See http://www.rand.org/

Acknowledgements Universitas Indonesia, Center for Research and Integrated

Development Tropical Health and Infectious Diseases

Pasteur Institute and International Pasteur Institutes Network: Institut Pasteur du Cambodge: Dr Sirenda Vong, Dr Sowath, Dr Laurence Borand, Sophie Goyet, Dr

Philippe Buchy, Dr Bertrand Guillard. Pr Jean-Louis Sarthou, NIHE: Pr Nguyen Tran Hien, Dr Nguyen Thi Thuong, Dr. Nguyen Van Duong Institut Pasteur Nha Trang: Pr Bui Trong Chien, Dr. Vien Quang Mai, Dr.Trinh Thi Xuan Mai Institut Pasteur Ho Chi Minh Ville: Pr Tran Ngoc Huu, Dr.Kien Quoc, Dr. Huong Vu Thi Hu Que Institut Pasteur de Shanghai: Dr Wei Wang, Dr Peijun Ren, Dr Jin Zhang, Dr Changgui Dong, Dr Yize Li, Dr

Peng Lu, Dr Vincent Deubel, M. I. Robin NCLE: Dr Phengta Vongprachanh, Dr Hansila Phoupaseuth, Dr. Somvay Ongkhammy, Dr Matthida, Dr

Darouny Phonekeo, Dr. Noikaseumsy Sithivong, Dr Thongchanh Sissouk, M. Phayvan, Dr Anne-Charlotte Sentilhes

Unité de Coordination : Mme Silvia Ostberg, Dr Roberto Bruzzone (HKU-Pasteur Institute Institut Pasteur Paris: Dr Isabelle Catala, Dr Marc Jouan, Dr Arnaud Fontanet, Kathrin Victoir

REDI centre: Dr Rodney HOFF, Dr. Za Reed, Dr Philippe Cavallier, Mrs. Quake Ai Li

NUS: Pr. CHIA, Dr. Elizabeth Alderman Jahncke

And International SOS/AEA company

Health & Medicine

Surveillance of emerging diseases and networks