PPT by jizhen1947


									    2nd ASEAN China International Bioinformatics Workshop, April 2008

 Collaborative Opportunities on Bioinformatics in the
          Diagnosis of Infectious Diseases:
Our Preparedness in Battle Against
        Avian Influenza?

                      Albert Cheung Hoi Yu, Ph.D.
                    Infectious Disease Center, Peking University
                          Professor and Vice-director
               Neuroscience Research Institute, Peking University
                                  Chairman and CEO
                          Hai Kang Life Corporation Limited
                         Beijing Hai Kang DNA Chips Limited
Avian Influenza (AI) – A Global Threat !
Influenza Pandemic Preparedness Plan

   Surveillance–in man & animals
   Stockpiling and logistics
   Emergency responses
           Public health
           Community
   Public communication
   Coordination and command
                                 Phases of Alert
                   WHO                       Very similar                                    China
 Inter-pandemic                                                                New virus isolated in
                        Low risk of
      Phase                                   1                                humans but triggered
                       human cases                                             no immune response
 New virus in                                                                  OR immune response
  animals, no          Higher risk of                                            triggered but no
 human cases           human cases                                                   symptoms

                                                    Degree of Response
                     No or very limited                                          Human infection
   Pandemic          human-to-human           3                          III    with no human-to-
     Alert                                                                     human transmission
                                                                                                         Preparatory Stage

                   Evidence of increased
New virus causes     human-to-human           4
   human cases
                   Evidence of significant
                     human-to-human           5

                                                                               Efficient and sustained
                   Efficient and sustained                                        human-to-human
   Pandemic           human-to-human          6                           I        transmission OR          Pandemic
                         transmission                                          WHO announcement of
                        Strategy of AI Control In China
                                   National Ministry of Public Health
                     [ With Provincial Departments of Health, Local Health Bureaus ]

                                                                                                  3. Reporting of
                                    4.Communication,                                                 confirmed
               Provide medical        feedbacks &                                                    diagnostic
               expert teams to        proposed                                                       result
               support diagnosis      response
               / treatment
                                                                                       National CDC
Direct & Real-time                             National Medical
access to medical
records through                                 Expert Team                                      2. Reporting /
online reporting
system                                                                                             Delivery of sample
                                                                                                   for diagnosis &

              Provincial Medical                       Cooperation :                   Provincial CDC
                  Expert Team                          Diagnosis and
                                                                               1. Reporting of

                                        Suspected AI Case identified
                                        in Local Hospital
                                        [by Local Medical Expert Team and Local CDC]
      Surveillance of AI in Animals
During outbreak:
  Detection and report of infection by farmers and
  volunteer, based on clinical criteria (5% deaths in
  flock), to activate pre-emptive culling, confirmed by
  lab. (cloacal swab – viral isolation)

After outbreak:
 Maintenance of clinical-based surveillance with lab.
   testing to confirm freedom from disease in control
   zone around infected area for 21 days, then 5 months
 Proactive countrywide community survey to detect
   and destroy infected flocks, then twice a year
      Surveillance of AI in Humans
Detection and report of all pneumonia & flu-
like illnesses with history of exposure to
sick/dead poultry or of contact with pneumonia
Nasopharyngeal swab of all cases sent for rapid
flu test, and conventional test for H5N1.
Investigations of all reported cases by trained
epidemiology teams.
Daily situation monitoring, daily update on
website .
Pandemic Planning Diagnostic Pyramid
AIV Family Tree
               Evolving Viruses
• H5N1 viruses in 1997, 2003, 2004 and 2005 are
  genetically and antigenically different
• Different virus clades encountered in countries of the
   • Clade 1 (Lao, Thailand, Vietnam, Cambodia, China)
   • Clade 2-subclade 3 (China, Thailand, Cambodia,
   • Clade 2-subclade 1 (Indonesia)
• Sequence variation should be considered in diagnostic
The Battle Against Infectious Disease
 To defeat an infectious disease, you must
  control its transmission from infected
          people to healthy ones.

     The critical issues are planning,
surveillance, and getting an early warning.

 It was important to find ways to rapidly
   tell people that they are not infected.
AI in China
Outbreaks of AI in Poultry and Human Cases in Thailand
    Jan-May 2004                    Jun-April 2005
                                                       May 2005- Dec 05

      Confirmed case
      Suspect case
      Area of outbreak in poultry

                                                     Source: BOE, MOPH
                 Lab Conditions
• No temperature control nor heating– temp in lab was
  about 10oC

• Walls and floors did not have appropriate covering
  (tiles and bumpy lino)

• Electricity supply not guaranteed (no generator);
  interruptions experienced during testing

• No freezer below about 8oC
      Challenges for Diagnostics
 from Global Public Health Perspective
As accurate as necessary
– to ensure WHO's public health responsibilities fulfilled

As quick as possible
– to detect the emergence of new variants of human pandemic potential
– to trigger outbreak response, investigation and rapid containment
   whenever needed

As simple as possible
– the majority of diagnostic labs in the world does not have advanced
   lab settings
– many crucial diagnosis conducted under huge pressure
                                          Current Detection
• Respiratory distress   Virus                Methods
                                         Ag / Ab-based method
• X-ray evidence of
  lung damage                            Microbiological evidence
                                         of virus (virus isolation)
• Fever
                                         Conventional PCR
                                         Real time-PCR
Users                                    NASBA
•Where?                                  New Method
•Who? User-friendly?                     Modified Enhanced real
•Affordable?                             time-PCR

Amplification Technology of NASBA

                   Isothermal amplification technique
                    comparable results within different test units
                   Simplified operation process

                    reduced contamination, higher reproducibility

                                     PCR’s false
                                    positive result
                  NASBA Protocol

Step 1. Reagent mixing        Step 2. Isothermal incubation
                              (can be replaced by a heat block)

Step 3. Probe hybridization   Step 4. Signal detection by ELISA reader
NASBA System

               Adapt to regular
Participation of NASBA-EOC Detection in the
       Influenza Surveillance Program
Commissioned by the National AIV Task Force

 NASBA-EOC: Takes part in the project implemented by
  National AIV task force
 Surveillance of avian influenza virus (generic and
  subtype H5), human influenza virus, parainfluenza
  virus, and other selective pneumonia-causing
  pathogens in Beijing population
 Beijing Hai Kang DNA Chips Limited provides NASBA
  AIV / H5 test kits for the surveillance program
National Task Force for Human AIV

    Training on AIV diagnosis using the NASBA EOC method to
       the National AIV task force members in Beijing, China
Multiplex NASBA!
Molecular Pneumonia Detection Systems
 Project awarded by the China Ministry of Science and
  Technology (a “863” project)

 We collaborated various hospitals in Beijing including
  hospitals affiliated Peking University, Chao Yang Hospital,
  You An Hospital and Di Tan Hospital of Capital Medical

 Development of multiplex NASBA, ERT-PCR and other
  detection system/ technology for various pneumonia-
  causing pathogens (including SARS, AIV, influenza, etc.)

 Development of a Lab-On-A-Chip (LOAC) system
Was it possible to establish
rapid and accurate tests for
 Infectious diseases in an
    outbreak situation?
Difficulties in Getting Good Diagnostic
              Kit Validated!
   • Adequate clinical samples
   • Well characterized samples are
     indispensable for the development and
     evaluation of diagnostic test
   • Appropriate and adequate specimens
   • Good quality
   • Adequate clinical information
   • Appropriate labeling and storage
   • Good data management
Development of Sustainable and Integrated
         Management System
1. Development of knowledge management
   mechanism during the inter – pandemic period
2. Development of knowledge management
   mechanism during pandemic
3. Establishment of a system for coordination and
   communication among various organizations
   during pandemic
4. Coordination with foreign and international
5. Monitoring and evaluation
                    Major success factors for AI control

 Strong leadership and support of the Government
 Close co-operation between public health and animal health authorities, and among partners in
   multi – sectors
 Proactive risk communication to the public and strong public involvement
 Extensive international collaborations, especially with WHO, OIE, FAO, APEC,ASEAN-
 Existing infrastructure (surveillance, laboratories,
 disease control, hospital infection, trained personnel)
The influenza epidemic of
1918 killed 20 million in just
18 months. With 25 million
Americans alone infected
during the influenza epidemic, it
was hard to provide care for
everyone. The Red Cross, seen
here with masks over the faces
of the nurses, often worked
around the clock.
Source: Courtesy of the National Library Museum.
CNN - “Businesses brace for pandemic”
          3 November 2005

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