Survelliance Flashcards
Surveillance definition
-Systematic continuous observation of populations, and collection and analysis of data from many varied sources
FOR:
Rapid detection and timely, appropriate response to important health events
AND:
Production and communication of valid information about the health and disease status of the population
Purposes of Surveillance
- Rapid detection of disease outbreaks
- Support Dz control/eradication
- Assess population health and safety of food
- Produce information about disease
- Evaluate disease control/biosecurity programs
Rapid detection of disease outbreaks
- Rapid detection of disease outbreaks
– Endemic, foreign, emerging
– Early detection prevents catastrophic losses and costs
–
• Direct costs: dead animals, treatment for sick animals, lost productivity
• Indirect costs: lost markets, lost consumer confidence, losses in tourism, loss to rural economies: agriculture has a 3-4 times multiplier effect
Eg. The FMD outbreak in the UK 2001
Support dz control/eradication
- Support dz control/eradication
During an outbreak
– Situational intelligence
– Identify suspect or infected farms for stamping
out
Control eradication program
– Identify infected farms for control measures – Eg test and slaughter programs
Assess the health of populations and safety of food products
A. OIE member nations obligated to scientifically estimate the disease risk associated with their animals and animal products
Amount of dz or freedom from dz
Essential for trade
Requires surveillance, well trained veterinary service, diagnostic laboratory system, legislation to facilitate disease control
B. OIE member nations are required to report the occurrence of listed and emerging diseases
• Requires OIE acceptable surveillance
– Borders will close if trade limiting disease is
detected, but open faster with good surveillance
– Borders can be closed if a nation has substandard surveillance, even if no disease has been detected
Produce information about diseases:their importance,changing distribution,and changing risk factors
Produce information about diseases:their importance,changing distribution,and changing risk factors
Information used for:
• Setting research priorities
• Emergency preparedness
• Gov’t directed disease control programs
• Veterinarians and farmers to manage disease
Evaluate effectiveness of disease control, biosecurity and border security programs
Evaluate effectiveness of disease control, biosecurity and border security programs
– Surveillance detects failure of biosecurity and border security programs
What are the 3 components of surveillace?
- Detection
- Response
- Communication
Detection
Observation of a population or collection, analysis and interpretation of data from a population
– Disease outbreak investigation and diagnostic pathology are part of detection
Goal: timely detection or identification of: – Important disease events in the population
• FADincursions,EmergingDzes,EndemicDzoutbreaks
– Significant changes in the health status of the population
– Significant changes in risk factors for diseases in the population
Response
The immediate response to disease outbreaks and events is considered part of surveillance
– Pre-determined/defined response to a defined event – Eg. the immediate response to a case of FMD
– Eg. Holding a carcass with lesions/ tumors
Goal: Timely, appropriate response to Dz events
– Minimize the impact (loss of animals, productivity,
markets)
– Minimize the cost of the response
Communication
Goal: Produce and communicate timely accurate info about the health/dz status of the population
1.
For outbreak response
– Situational intelligence during an outbreak (define the problem)
– Information for emergency preparedness
For dz control and management
– Changing patterns of endemic diseases
– Changing patterns of risk factors for disease
– Absence of dz
– Effectiveness of biosecurity, border surveillance, disease eradication and control programs
Passive Surveillance
– Submission is initiated by and at the discretion of the sample/data provider
– Veterinary/health authority does very little to select subjects for sampling or information
• Reportable dz programs: Veterinary/health authorities expect/obligate clinicians (or laboratories) to send in reports, they don’t actively go out and select who will be sampled or provide information
– Little or no control over who provides samples/data
Examples of Passive Surveillance
– Reportable disease programs
• While mandatory, they are passive because farmers, veterinarians, physicians, laboratories initiate the reporting……..at their discretion
• Egs BSE, Scrapie, CWD surveillance, rabies, foodborne illness
• WAHID or WAHIS displays diseases reported to the OIE
– Sero-surveys at auction markets and slaughter plants • Animals are presented for slaughter or sale at the discretion
of the owner
– Diagnostic laboratory submission surveillance
• Owners/vets/physicians submit samples for diagnostic testing at their discretion• • •
Real time surveillance (Syndromic = pre diagnosis) Emergency room/ambulance records Physician/Veterinary practice medical records Sales of pharmaceuticals Absenteeism from schools, public service Promed mail Digital disease surveillance Healthmap
Pros and cons of Passive Surveillance
– Pros:
• Reportable disease programs provide continuous surveillance – Great for early detection of important,obvious,easy to diagnose
diseases…….only if veterinarians are well trained to recognize the disease • Laboratory surveillance can detect emerging diseases
• Inexpensive
– Cons:
• Little control over who provides data/samples
• Not a representative sample of the population
• Won’t work for less valued animals that don’t use veterinary services
• If disease is stigmatized farmers won’t report
What is the most common type of surveillance?
Passive
