As part of the Major Packer Surveillance program (MPS), states conduct a pseudorabies test on all blood samples collected from breeding swine which are slaughtered at participating plants and which originate from a state on the MPS list. The testing state reports the total number of samples received to the states of origin at least quarterly. The backtag number (or other ID), collection date, and test result for positive samples are reported as they occur. Beyond these few simple steps, there are no requirements for the routing and timing of reports nor for the inclusion of other data which may be useful for program managers in the states of origin, such as the tag numbers of negative animals or the collection plant name.

Are there major problems with MPS reporting that compromise the success of the PR eradication effort? Probably not. Is the system inefficient and are we missing an opportunity for gaining the most value in terms of overall program management? In my view, yes. The inefficiencies stem mostly from the fact that little of the information transfer is done electronically. This in turn is a result of the lack of both a scannable form of ID and of mutually compatible software for data collection and transmission among the various states. In addition, because no standardized reporting system exists, there is no easy way for a state to know if it is being properly credited for samples collected from its breeders slaughtered in other states.

This is how it could work. Imagine that you are a state PR program manager. Each week you get a report from markets in your state indicating the backtag numbers applied, the dates of application, and the owners’ names and addresses. (This is already done in some states.) A clerk enters only the tag numbers and the dates in the computer. (The names and addresses of positives can be looked up by hand and probably are not worth the time it would take to enter them all.) Every month you receive from a central source a listing of all backtags from your state collected at slaughter, the state, date and plant of collection, the test used, and the test result. By merging the reports from your markets and from the central data source, you can now determine the following:

t The proportion of tags applied at each market that are collected at slaughter

t The geographic distribution of the origin of slaughter

t Surveillance samples using market location as a surrogate

t The length of time animals were in slaughter channels

t The states and plants where your culls are slaughtered

t The proportion of positive slaughter samples that trace to a negative herd by market, plant and state, and the total number of animals tested.

The value of this information for a program manager should be obvious. The burden this system would place on the testing state need not be great. With a scannable backtag, the data entry clerk in the slaughter state need only enter the date and plant name once. The laboratory ID and test type would be added automatically. Each tag is then scanned and the test results can either be automatically entered from the ELISA or PCFIA reader or by hand for positives only. There are now only 8 items in the data set: state of origin, date of collection, plant of collection, tag number, test used, result, testing state and laboratory. This data set could then be sent electronically to a central computer which will sort the data by state of origin and issue individual state reports.

The results from positive samples could be sent daily to the central data base and downloaded to each state of origin automatically. This would reduce the current interstate report time of days and weeks to the same or next day. The states of origin could transmit to the central data base the disposition of the traces from positive samples, including backtag number, thus improving detection of collection problems in plants. (Except for states with large numbers of breeding swine going to specific plants, the identification of problem plants should be done on a national basis.)

Would this system be worth its relatively small but not insignificant investment in equipment and personnel? Like the answer to all such questions, it depends. We expect states to maintain an arbitrarily set level of surveillance that is representative and random. This gives the impression of great precision, but in reality we have little ability to evaluate slaughter surveillance according to these criteria. When and if individual premises animal ID is adopted, an automated means of tracking herds will be of even greater necessity. How much taxpayer and producer money are we spending unnecessarily on surveillance? Can we answer that question with our current system? Is a system that was developed many years ago still relevant to a rapidly changing industry, increased expectations for efficiency in government, and innovations in data processing?

While we are waiting for the above, what can we do to make the current MPS reporting system more efficient? First, we must understand the problem. A typical routing of positive test results goes from the state laboratory to the state veterinarian to the AVIC in the state of origin to the state veterinarian in the state of origin. This is a logical, if not involved, progression. However, just to make sure that no one is left out, several persons in the chain send copies to each other, and thus a lot of unnecessary paperwork gets generated. One solution would be for Swine Health Staff to request of each AVIC the name of the person making interstate slaughter testing reports and the name and address of the person to whom such reports should be sent. Using the list, only one report per state need be sent. The designated recipient can distribute the information to the appropriate persons as he or she sees fit.

The monthly or quarterly reports of total samples processed should be sent to Swine Health Staff and to the designated recipient in the state of origin. There is no standardized method in place to ensure that slaughter samples are properly credited. The person responsible for issuing reports in each state should make sure that notices are sent to the appropriate states. There have been instances recently where this was not being done, thus depriving some states of needed slaughter surveillance numbers. Because of the artificial barrier created by USDA regional boundaries, as a regional epidemiologist, I frequently get slaughter sample reports from states within the Northern Region, but I never get reports from states outside the region. Thus, I have no way of monitoring slaughter surveillance for states in the region whose breeders are slaughtered in other regions. My other counterparts have the same problem. For this reason, we should be producing summary reports of slaughter surveillance for the country as a whole. The reports should be in the form of a table with states of origin on one axis and testing/slaughter states on the other. The cells in the table would contain the number of samples tested in each slaughter state that were provided by each state of origin. A spreadsheet to produce such a table from individual state reports would be easy to create.

A final note on improved efficiency: it is not clear on some states’ reports if the date refers to the collection date or the test date. This should be clarified.