dr. farooq presentation
TRANSCRIPT
Surveillance Strategies and Sample
Collection
Muhammad Farooq TahirDisease Surveillance Officer
Poultry Research Institute
Rawalpindi
Surveillance Definition-Dictionary
“Close observation,
especially of a
Suspected spy
or criminal.”
ORIGIN: from Fr., from sur- 'over' + veiller 'watch'Source: The Concise Oxford Dictionary. Ed. Pearsall J. Oxford University Press, 2001.
Surveillance
“Surveillance is the ongoing
systematic collection,
analysis and interpretation
of data to describe
and monitor a health event;
and the dissemination of information to those who need to
know in order that action may be taken .”
Klaucke,1992
Disease Surveillance
• The continuing scrutiny of all aspects of
occurrence and spread of disease that are pertinent
to effective control.
Early warning
Presence or absence of a disease
Source: Last JM. A Dictionary of Epidemiology (Second Edition). Oxford University Press 1988, New York.
Objectives of Disease Surveillance
To monitor trend & magnitude of diseases
Epidemic (outbreak) detection and prediction
Early warning
Design/change vaccination policy
Estimate Future Disease Impact.
Evaluate interventions to improve them
Certify elimination / eradication of a disease Monitor
progress towards a control objective
Facilitate planning
Types of Surveillance
PASSIVE SURVEILLANCE
Where reports are awaited and no attempt
made to actively seek reports from
community.
ACTIVE SURVEILLANCE
Where veterinary services actively move to
the community to seek the disease reports.
Passive Surveillance
Receives data from all potential Veterinary
Dispensaries, Hospitals, Labs etc
Often minimal/incomplete.
Usually data received in irregular pattern as by thefield staff.
False Positive Results
Requires Less Resources
Active Surveillance
Usually conducted for specific disease.
Requires substantial more time and more
resources.
Often used when outbreak has begun and
is suspected to track new cases.
Usually complete and in a regular pattern until
the outbreak is controlled.
How Surveillance is Conducted
Surveillance
Disease/
Event
Data/ Samples
Information
Intervention
Sample Collection
Laboratory diagnosis is theonly tool to confirm adisease but it all depends onCorrect Sampling
Sample Types for PoultrySample Type Objective
Swabs Virus detection
Tissue Virus detection
Feces Virus detection (Less Sensitive)
Blood/ Serum Screening for pathogen
Flock monitoring
Swabs
• Two kind of swab samples Tracheal & Cloacal
• Take 2-3 ml of transport medium in the sterilized
swab
• For taking tracheal swab open the beak of bird
• Insert the swab deep to the pharynx
• Gently rub it
• Put the swab in the transport medium
• Properly label and pack it
Swabs cont….
• For taking Cloacal swab
• Locate the Cloaca of the bird
• Insert the swab deep in to Cloaca
• Rub it gently
• Put it in transport medium
• Properly label and pack it
Cont….
Transport MediumSampling tubes should be filled with 2-3ml Transport
medium with antibiotics
PBS/BHI with :▫ 10 IU/ml Penicillin▫ 10 mg/ml Streptomycin▫0.25 mg/ml Gentamycine▫ 5 IU/ml Mycostatine
After addition of the antibiotics the pH must be adjusted to pH 7.0-7.4
If not available:
Use NaCl 0.9% (Normal Saline) or MEM
Tissues
Fresh ORGANS or organ pools (2-5 birds) to be taken
Trachea, lungs
Intestine (incl. content)
Liver, spleen
Brain (especially when nervous signs)
All other organs with lesions
Use sterile and water tight containers
cover with transport medium
Pooling of Samples (Swabs & Organs)
Max 5 birds for one pool
Same species
Samples from the same unit
Separate tracheal and cloacal swabs
Separate organs
Feces
Faecal material must be fresh!
Optimum 1 g
Only to be used if no other sampling possible, as
less sensitive
Use sterile and water tight containers
Can be used for market surveillance purpose
Blood Objective
Serology
MaterialSyringe 2.5 ml
Needle: 21, 23 G
Hemolysis tubes or vacutainers
Sample sizeIdeally 1.5 ml
Min 0.5 ml
Blood
Sampling for ALP Project
• Major focus on ND, AI, IB and Salmonella
• All types of sampling required
• No fixed target or quantity but 200-300 samples
monthly appreciated.
• Proper sampling with history on prescribed
proforma.
THANKS FOR THE ATTENTION