Surveillance System Standards

disease confirmation.  Limitations should be identified and addressed. 

The type of diagnostic test and cutoff point or dilution used to define 

categories of cases may be included in the case definition. 

  The type of test (e.g. ELISA, PCR, etc.), and any additional particulars 

specific to the testing, should be included if applicable.) 

  The test should adapt to changing technology as new methods are 

established and are determined superior to older methods. 

 

Case classification 

(definition 

categories) 

  Case classifications usually represent various levels of certainty and 

include categories such as suspect, probable, and confirmed.   

  Categories should be clearly defined and mutually exclusive.  

   Levels of certainty may be defined using clinical signs identified 

through physical examination of the animal, antemortem or 

postmortem laboratory diagnostic tests, gross necropsy findings, 

histopathology, or the opinion of a recognized expert such as a 

foreign animal disease diagnostician (FADD).   

  Reporting criteria may vary depending on level of certainty. 

 

Required 

comments 

  Surveillance plans may require certain forms of disease to be 

reported (e.g., fever, encephalitis, or meningitis); documentation of 

the vaccination status of the animal, herd, or flock; type of vaccine 

used; or lot number.  Environmental exposure history of the animal, 

flock, or herd; history of arthropod exposure; or history of importation 

of animals, semen, or embryos from an endemic country or state may 

also be needed.  Other information such as feedstuff or water source, 

evidence of foreign animal disease exposure or intentional release, or 

reproductive status could also be included in the case definition. 

 

1.8 Data Sources  

Standard:

 

All data sources for the surveillance system are clearly identified.

 

 

 

Supporting Information: 

 

Surveillance efforts typically rely on data from multiple sources.  Some examples of data 

sources include:  

 Producers 

 

  Private practitioners or veterinary teaching hospitals 

  Veterinary diagnostic laboratories, (e.g., university, State, Federal, or private) 

  Government agencies, Federal, State, and local (e.g., animal health and agriculture 

agencies: FSIS, NASS, ERS, CSREES, FSA, RMA, RD, NRCS, etc., U.S. customs or 

border patrol, EPA, USGS, DHS, DHHS, Census Bureau, and others) 

 Brand 

inspectors 

  Affiliations or professional organizations, (e.g., milk marketing boards, registries) 

  Businesses, (e.g., abattoirs, packing plants, pharmaceutical companies, zoos) 

 Livestock 

markets 

 Slaughter 

plants 

 Renderers 

  Business reporting services 

 Surrogate/proxy 

data 

 Aerial 

imagery 

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The surveillance documents should clearly describe all data sources that the surveillance 

system is expected to include, as well as associated strengths and limitations.  

 

1.9 Sampling Methods   

Standard: 

Sampling methods are thoroughly detailed in a surveillance plan or equivalent 

document.  

 

a.  The sampling methods include methods to assure: geographic 

representation without introducing spatial bias, an appropriate level of 

sampling, and a measurement method that ensures appropriate 

denominator information for analysis. 

b.  Sample size is determined with appropriate mathematical and 

epidemiological justification including measures of overall sensitivity 

such as design prevalence, detection limit, and level of confidence. 

c.  Sampling methods include information on modes of data collection, 

triggers for data collection, frequency of data collection, and transmittal 

of field or laboratory data to program managers or coordinators. 

d.  Sampling strategy should address and avoid unintentional bias, (e.g., 

sample selection, collection, reporting, and confounders.) 

e.  Test sensitivity, specificity, and predictive values are considered in the 

sample strategy. 

f. 

Methods of data collection are described for each identified data source. 

g.  Sampling methods carefully consider data sensitivity and confidentiality 

issues. See Chapter 3 for data confidentiality standards.  Applicable 

Federal regulations should be noted. 

h.  Changes to sampling methods for the surveillance system are 

appropriately documented and include a rationale for the change.  

 

 

 

Supporting Information: 

 

All sampling procedures and protocols, including field and laboratory data collection 

techniques, should be documented, including changes to data collection procedures as new 

procedures are identified to enhance the system.  This information may be found in 

surveillance plans, uniform methods and rules, the code of Federal regulations, or annual or 

progress reports. See Chapter 3 for additional information on training staff for data collection 

and data confidentiality standards.  

 

Population parameters are clearly described, including populations involved in the study and 

surveillance as well as populations for which inferences are being made. See standard 1.6, 

population characteristics.  

 

 

 

 

 

 

 

 

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