Except for a few "hot spots" in a trio of states, the national pseudorabies (PRV) eradication program is progressing fairly well. It's still on target to meet the deadline of the end of the year 2000.
That's the word from Arnold Taft, a federal veterinarian with USDA who coordinates the state-federal program.
Taft says while most states are moving ahead, there are some herds that are not progressing, still spreading the virus. To meet the eradication goal, the cleanup effort must be accelerated, he urged at a PRV meeting during the annual meeting of the U.S. Animal Health Association (USAHA) in Minneapolis, MN. Remaining 'Hot Spots'
There are three remaining areas - in the hog-dense areas of north and central Iowa, southern Minnesota and central Indiana - with significant levels of active PRV infection. That trio accounts for 936 quarantined premises out of a total of 1,305. That compares with 2,069 quarantined herds a year ago, says Taft.
In North Carolina, there are still 232 quarantined, infected herds in three counties, reports Tom McGinn, DVM, North Carolina Department of Agriculture. There are 202 in Stage 2 (voluntary herd cleanup phase), 30 in Stage 3 (mandatory herd cleanup).
But, he points out, there are only 34 PRV-infected sow herds left in the state, 170 quarantined finishing feeding floors and 28 quarantined nursery premises. Word is all quarantined sows will be gone by the end of 1998, speeding eradication.
The remaining PRV cases are scattered out in eight states and the less densely populated areas of Iowa, Minnesota and Indiana, explains Taft.
Revolving Door? The main challenge to completion of eradication is area reinfection, says Taft. He says you wouldn't think, in the latter stages of this program in fiscal year 1998, that there would be any new, infected herds, but there are. They are shown on the map.
"Too many times, new herds break with PRV and you go back to the source and they're negative," says Taft. That points to operations becoming too lax.
That is a notable concern for Iowa, says PRV program director Lawrence Birchmier, DVM. Iowa registered 1,034 quarantined, infected herds as of September 1997. That figure has dipped to 632 herds a year later.
But Birchmier laments that half of the current PRV infections in the state have occurred since 1997. A big part of that problem is the fact that new, infected herds are cropping up at the rate of about 20 per month.
In Minnesota, where several breaks occurred early this year, eradication progress has slowed since 1996, says Paul Anderson, DVM, state board of animal health. There were 149 herds on quarantine as of Oct. 1, 1998, compared to 177 a year earlier.
Area spread within multi-site operations has been a problem, he says. He also expressed concern that the state has recently experienced more hot, clinical outbreaks of PRV, including a 3,000-sow unit that had been vaccinated before breaking with the disease.
Indiana has 214 quarantined herds as of Oct. 1, 201 in Stage 2, 13 in Stage 3, according to John Johnston, DVM, director, Swine Division, Indiana Board of Animal Health. The series of outbreaks this past winter has slowed progress.
But Johnston vows the state expects to be cleaned up by the first quarter of 1999, fueled by their new, emergency PRV rule which should be in place this year.
That rule mimics the federal test-and-removal rule which calls for sows in all quarantined, PRV-infected herds to be tested before or at the time of farrowing. Sows testing positive must be removed for slaughter or placed in isolation for slaughter within 15 days of weaning. Boars must also be removed within 15 days of testing positive for PRV.
In Illinois, only 14 quarantined herds remain, reports state veterinarian Richard Hull. He expects all but one problem herd to be cleaned up in nine months.
Nebraska had 23 quarantined herds for PRV a year ago and has dropped to 17, reports James Weiss, DVM, Nebraska Department of Agriculture.
Michigan probably has made the most progress of any state in the program, says USDA's Taft. Some 3-4 years ago, they were saddled with more than 150 infected herds. Today they are down to three infected herds, projected to be released by January 1999.
South Dakota, which had completed cleanup of all PRV infected herds, suffered a setback recently with the discovery of several infected herds.
In response, the state passed a new rule effective Nov. 1, 1998, for incoming hogs. It requires imported hogs from a state with a split PRV status (Stages 2/3) come from a farm on which all hogs have been randomly tested within 30 days of shipment, or come from a negative farm that is maintained by monthly testing.
In resolutions passed, the USAHA PRV committee called for a review of the swine slaughter surveillance program, which is used in many states to monitor successful completion of PRV eradication. North Carolina and Indiana don't participate in the program, however.
A resolution was passed urging USDA to create a task force to address future budgetary issues, strategic planning, leadership and guidance so that eradication goals can be fulfilled.
USAHA's PRV committee endorsed a report by an industry task force on long-range surveillance. The report stressed focusing surveillance for the disease after eradication on high-risk areas including the border with Mexico (which is still infected with PRV), areas with infected feral (wild) pig populations and areas with recent high prevalence of the disease. The group called for development of a special surveillance program for Florida because of the possible entry of exotic swine diseases and the state's large feral swine population.