January 01, 2005


 Succeeding against pseudorabies

Posted Dec. 15, 2004

The National Pseudorabies Control Board has announced that commercial swine herds in all 50 states are free of pseudorabies for the first time in U.S. history. The board made the announcement during the U.S. Animal Health Association meeting this past fall. Pseudorabies has existed in the United States for at least 150 years, and the disease is still endemic in feral swine.

"This is tremendous news for the pork industry and is a direct result of producer-driven programs to eradicate that were started in 1989," said Keith Berry, president of the National Pork Producers Council. "PRV has hurt U.S. pork producers, costing them an estimated $30 million annually through vaccine costs, testing, illness, loss of production, and loss of access to some foreign markets. We are pleased to have won the war on this devastating disease."

The war has been a hard-fought one. In 1989, the Department of Agriculture Animal and Plant Health Inspection Service established a voluntary eradication program for pseudorabies that focused on vaccination and enhanced biosecurity. The program was cooperative in nature, involving federal, state, and industry participation.

Producers and government agencies worked hard and dramatically reduced known infected herds from approximately 8,000 in 1992 to 1,300 in 1998. This was less than one percent of U.S. swine herds at that time.

In 1998, the program suffered a setback. Depressed market conditions led some producers to stop vaccinating herds, which resulted in an increase in infected herds. In 1999, the USDA renewed its efforts with the launch of an accelerated eradication program. This program involved reimbursing owners for their animals at market value as well as reimbursing owners for euthanasia and disposal costs.

In the fall of 2004, the last three states that had commercial production swine under surveillance for pseudorabies—Texas, Florida, and Pennsylvania—were deemed free of the disease.

If the United States remains free of pseudorabies infection in commercial swine, the target date for the USDA-APHIS to declare the country officially free of the disease is October 2006.

According to Berry, many farmers continue to vaccinate their breeding herds for the disease, and random testing of swine herds will continue. Dr. Paul Anderson, chair of the USAHA Committee on Pseudorabies and assistant director of the Minnesota Board of Animal Health, notes that a remaining challenge is to ensure that feral swine, some of which are infected with pseudorabies and brucellosis, do not come into contact with commercial swine herds.

The USAHA committee is calling for federal agencies to continue long-range funding for research, program support, and field studies in feral swine. In particular, the committee believes funding is needed for conducting population studies that support disease risk-management strategies; developing Brucella strain VTRS-1 for use as a dual vaccine, along with field trials to demonstrate its efficacy; and studying how brucellosis and pseudorabies might be transmitted to domestic swine.