Surveillance

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					Surveillance

    Dr Huda Hassan Mohamed
   Consultant in Communicable
          Disease Control
    West Midlands East Health
          Protection Unit
Learning outcomes
   Definition
   Types
   Principles
   Functions
   Sources of data
   Methods
   Dissemination of information
   National Surveillance Centre
   Exam Tips
Surveillance
   the continuing scrutiny of all aspects of the
    occurrence and spread of a disease through
    the systematic collection, collation and
    analysis of data and the prompt
    dissemination of the resulting information to
    those who need to know so that action can
    result

               Information for Action
Types
   Passive
   Active
Surveillance standards
   ongoing
   practicable
   consistent
   timely
   accurate
   complete
    The purpose of
    surveillance
   individual case management to prevent
    spread
   measures change in incidence…detect
    outbreaks
   track changes in occurrence and risk
    factors..target interventions
   evaluation of control measures
   emergence of new infections of public health
    importance
    The principles of
    surveillance
   case definition
   case identified using a variety of data sources
   dataset is collected for each case, data collection
    form
   collated in a computerised database
   analysis of the data, production of summary statistics
   Interpretation, information
   Dissemination, action, continuing surveillance
Dataset
   Name, date of birth, sex, ethnic group,
    occupation, address, place of work,
    date of illness,
   clinical features, name of GP
   travel, immunisation
   food histories
   contacts, places visited
Data collection and
analysis
   Data collection form
   Computerised database, CoSurv
   Frequencies, rates
   Interpretation
   Dissemination
    Data sources
   statutory notifications of infectious disease
   laboratory reports
   outbreaks
   RCGP data
   HIV data
   STIs
   COVER
   mortality
   morbidity
   special surveys
Enhanced Surveillance
Programmes

Established by CDSC using multiple
  sources of data for infection of
  particular public health importance
 Meningococcal Meningitis

 TB

 E.coli

 CJD
Active surveillance
   National surveillance scheme for general
    outbreaks of infectious intestinal disease
   Medical Officer for School Association report
    illness in children in approx. 55 boarding
    schools e.g. influenza
   Surveillance unit of the College of Paediatrics
    and Child Health co-ordinates surveillance of
    uncommon paediatric conditions
2- Active Surveillance
   HIV infection in England and Wales are
    reported to CDSC
   Surveillance of Infectious Diseases at
    work (University of Manchester)
   COVER data (coverage of vaccination
    evaluated rapidly)
   Internet and e-mail
Surveillance: methods
     Laboratory surveillance
     Notifications
     GP sentinel surveillance

                Hospitals                Laboratories
                            Physicians                                                          Local Health Dept.




                  Weekly bulletin           Internet site                          Weekly summary    Individual notification




                                                  Communicable Disease Surveillance Centre
Laboratory Reports - The CoSurv Route
         Surveillance: Results -
         meningococcus
              Laboratoryreports* of Neisseria m                pe
                                               eningitidis, Ty B and C, in W  ales,
                 1975-2001** (Lab data analysed for CSF and blood specimensonly)

        140   Neisseria meningitidis
        120    ype
              T B
               ype
              T C
        100

        80
Cases




        60

        40

        20

         0
           75
           76
           77
           78
           79
           80
           81
           82
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           86
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           98
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           00
           01
         19
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         19
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         19
         19
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         19
         19
         19
         19
         19
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         19
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         20
         20
                                                Year
    Objectives of Surveillance for HIV and Other STIs

•   Identify risk factors and their distribution
•   Monitor levels of infection
•   Inform targeting of health promotion and monitor its effects
•   Monitor effects of antiretroviral treatment
•   Forecast care needs
•   Allow comparisons with other countries
•   Increase professional and public awareness
•   Inform policy makers and service providers
•   Detect new problems promptly
Sources of UK Surveillance Data: HIV, AIDS and Other STIs

  •   Clinicians’ reports of AIDS cases
  •   Laboratory reports of newly diagnosed HIV infections
  •   Laboratory reporting of CD4 counts
  •   Sentinel surveillance of diagnostic HIV testing (“denominator study”)
  •   Unlinked anonymous HIV prevalence monitoring
  •   Reporting of HIV infection in pregnancy and children (ICH)
  •   National survey of prevalent HIV infections diagnosed (SOPHID)
  •   Surveillance of tuberculosis and other AIDS indicator diseases
  •   Behavioural surveys and monitoring
  •   Reports from genitourinary medicine clinics (“KC60” returns)
  •   Laboratory reporting of STIs
  •   Reporting of results of screening blood donations for infections
  •   Mortality reports

               we know AIDS patients
     How by clinicians caring forabout HIV
    AIDS cases
   Diagnosed HIV infections (merged with AIDS data Jan 99)
      microbiology laboratories

      paediatricians/obstetricians

      clinicians (Jan 2000)

   Unlinked anonymous (UA) survey programme
       genitourinary medicine clinics (homosexuals and
        heterosexuals)
       for injecting drug users
       for pregnant women
       of specimens from newborn babies
       of women undergoing termination of pregnancy
               Surveillance of an HIV infection over time
                   (England, Wales and N Ireland)
Potential inclusion in unlinked
 anonymous seroprevalence
            studies

SOPHID / CD4 Surveillance

              Laboratory report of
                                                                   Clinicians   Reported
                 HIV infection
                                                                     report         by
             Clinician report of HIV                                 AIDS       clinicians
                     infection                                     diagnosis      / ONS




                                       Symptoms of HIV infection
                                                                   First AIDS
    HIV               HIV              Commencement of therapy                   DEATH
                                                                    defining
 infection         diagnosis
                                                                     illness
Surveillance developments

    Disaggregate KC60 dataset

    Gonococcal resistance to antimicrobials surveillance
     programme (GRASP)

    Enhanced syphilis surveillance

    Evaluation of chlamydial intervention

    Sexual behaviour
Surveillance: Dissemination of
information

Routine UK bulletins - paper and electronic
    Communicable Disease Report (CDR)- Weekly
     available from www.phls.co.uk / e-mail service


    Communicable Disease and Public Health (CDPH)-
     Quarterly
CDSC: Surveillance
Routine European bulletins - paper and electronic
         On behalf of DG V of the European Commission
         By editors of national surveillance bulletins of
          European countries
         Eurosurveillance weekly :
             - electronic only
             - produced at PHLS-CDSC Colindale
         Eurosurveillance monthly:
             - paper and electronic
             - French and English
2. Surveillance of immunisation
    A. COVER data
2. Surveillance of immunisation
   B. Disease incidence: Notified and confirmed measles


                     November 1994 - December 1998

                       1800                                                                                     80
                       1600                                                                                     70




                                                                                                                     Confirmed cases
                       1400                                                                                     60
     Notifications




                       1200                               Confirmed                                             50
                       1000                               Notified                                              40
                        800
                        600                                                                                     30
                        400                                                                                     20
                        200                                                                                     10
                          0                                                                                     0
                          94-11   95-03   95-08   95-13   96-05   96-10   97-02   97-07   97-12   98-4   98-9

                                                          Four week period
Centre for Disease
Surveillance Centre
National Surveillance Centre
England and Wales: Establishment
(1)
1973 Smallpox released from laboratory at LSHTM
     Committee of Enquiry, 1974.
National Surveillance Centre
England and Wales: Establishment
(1)
   1973 Smallpox released from Laboratory at LSHTM
        Committee of Enquiry, 1974.
   Recommendations: We need
     • a national information and co-ordinating centre

     • a national outbreak control centre

     • availability of specialist advice locally

     • a well-integrated public health service


               Adapted from: Report of the Committee of Enquiry into the
                  Smallpox Outbreak in London in March and April 1973:
                                                    London HMSO 1974
National Surveillance Centre
England and Wales: Establishment
(2)
   Decision to locate these within PHLS

   1977 CDSC established:
    Communicable Disease Surveillance Centre
   1996:
    Communicable Disease Surveillance Centre Regions
   2003:
    Centre for Infection
CIF functions
Surveillance = data for action
     to detect outbreaks (epidemics)
     to enable public health action
     to monitor trends in endemic disease
     to identify clues about disease aetiology
     to plan & monitor preventive programmes
     to evaluate an intervention
     to predict outbreaks (epidemics)
     to estimate future disease impact
Structure of surveillance
   Divisions - Example diseases:
    Immunisation division: Measles, Hepatitis, Meningitis, ...

    Respiratory division: TB, influenza, RSV, ...

    Gastro division: Salmonella, Campylobacter, ...

    STD/HIV division: HIV, Chlamydia, Syphilis, ...

    Health Care Associated Infections: MRSA, ‘Surgical site
                                             infections’, …
      Regional services
Surveillance within Europe
 European surveillance networks:
    Hosted at CDSC:
         - Enter-Net enteric infection salmonella, e-coli 25
         - EWGLI European working Group for Legionnaire Infecti
         - ESEN European Sero-epidemiology network
         - Meningococcal disease
         - STD
    Other:
         - EARSS European Antimicrobial Resistance Surveillance System
         - HIV
         - EuroTB
         -
Why there is a lot of emphasis
on surveillance now?
Getting ahead of the
curve
Good surveillance is the cornerstone:
 to control infectious disease

 tracking disease trends

 identifying new disease threats

 designing vaccines

 spotting outbreaks

 monitoring control measures
Disease threats
   Measles
   Jacob-Creutzfeld disease
   Clostridium novyii infection
   W135 meningoococcal disease
   Cryptosporidiosis
   E coli O157 infection
   STIs
   SARS
   Pandemic Influenza
Disease associated with new
technologies and new
behaviours

   Mobile phones
   travel
    imported foods
   bioterrorism
Learning outcomes
   Definition
   Types
   Principles
   Functions
   Sources of data
   Methods
   Dissemination of information
   National Surveillance Centre
Study guide
   Communicable Disease Control
    Handbook , J.Hawker Section 4, 4.2
    page 246
   Essential Public Health Medicine, R J
    Donaldson Chapter 9, Communicable
    Disease Parasites, page 388 – 391
   Control of Communicable Disease
    manual, James Chin, 17thEdition 2000.
Exam Tips
   General question on surveillance
-   definition, types, principles, function,
    examples
   Specific question on any type of
    surveillance programme e.g. HIV, Flu,
    legionnaire
   Follow a structure all the time
   Any questions
Good Luck

				
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