Hog cholera

Hog cholera is a contagious disease that -- as the name implies -- primarily affects pigs. The virus that causes it is often transmitted through direct contact between healthy swine and infected swine. There are three forms: acute, chronic, and mild. Because the disease was eradicated in the United States in 1978, animal health officials require pigs from foreign countries to remain in quarantine for 90 days before entering the country.

What Is Hog Cholera? Hog cholera, also known as classical swine fever, is a highly contagious viral disease among swine. How Common Is It? This disease was eradicated from the United States in 1978, after a 16-year effort by the industry and state and federal governments. Today, only 16 other countries are free of hog cholera. In the spring and summer of 1997, outbreaks of hog cholera were confirmed in Haiti and the Dominican Republic; both countries had eradicated the disease in the early 1980s. Also, in 1997, several European countries, including the Netherlands and Belgium, experienced outbreaks and suffered heavy economic losses. These outbreaks have animal health officials at the U.S. Department of Agriculture (USDA) concerned that hog cholera could spread to U.S. swine herds. While the disease does not cause foodborne illness in people, economic losses to pork producers would be severe if hog cholera were to become established again in this country. How Is Hog Cholera Transmitted? The most common method of transmission is direct contact between healthy swine and those infected with hog cholera. The disease also can be transmitted through contact with body secretions and excrement (feces) from infected animals. Healthy pigs coming into contact with contaminated vehicles, pens, feed, or clothing may contract the disease as well. Birds, flies, and humans can physically carry the virus from infected swine to healthy swine. Swine owners can inadvertently spread hog cholera through feeding their herds untreated food wastes containing infected pork scraps. Signs and Symptoms of Hog Cholera The clinical signs of hog cholera vary with the severity of the infection. There are three forms of the disease: * Acute * Chronic * Mild. Acute Hog Cholera The acute form of hog cholera is highly virulent (severe), causing persistent fevers that can raise body temperatures to as high as 107°F. Other signs of the acute form include convulsions and lack of appetite. Affected pigs will pile or huddle up together. Signs of hog cholera may not be apparent for several days following infection. Death usually occurs within 5 to 14 days following the onset of infection. Chronic Hog Cholera The chronic form causes similar clinical signs in affected swine, but the signs are less severe than in the acute form. Discoloration of the abdominal skin and red splotches around the ears and extremities often occur. Pigs with chronic hog cholera can live for more than 100 days after the onset of infection. Mild Hog Cholera The mild, or clinically unapparent, form of hog cholera seldom results in noticeable clinical signs. Affected pigs suffer from short periods of illness, which are often followed by periods of recovery. Eventually, a terminal relapse occurs. The mild strain may cause small litter size, stillbirths, and other reproductive failures. High mortality during weaning may also indicate the presence of this mild strain of the disease. How Can Swine Owners Protect Their Animals? Swine owners who suspect that their pigs may have hog cholera should immediately contact their local veterinarian or federal or state animal health official. Taking the following steps can help swine owners prevent the disease from occurring: * Check animals at least twice a week for unusual signs or behaviors * Make sure food waste is properly heated to destroy pathogens * Isolate newly purchased hogs for at least 21 days * Isolate sick pigs until the cause of illness is determined * Fence property to prevent wild pigs from coming into contact with domestic herds * Practice standard biosecurity measures, such as cleaning and disinfecting clothing, equipment, and vehicles entering and leaving the farm. How Animal Health Officials Protect U.S. Animals The USDA's Animal and Plant Health Inspection Service (APHIS) maintains a constant surveillance against the entry of foreign animal diseases such as hog cholera. To ensure that pigs are free of disease, swine from countries affected by hog cholera can enter the United States only after a 90-day quarantine at a high-security import center in Key West, Florida. Controlling Hog Cholera APHIS coordinates an emergency task force made up of federal, state, and local officials. This task force is ready to respond immediately to any outbreak of a foreign disease. If an outbreak of hog cholera should occur, the task force would take the following actions: * Investigate the affected farm to determine the history of illness, the types and number of pigs affected, and collect any other information relating to the illness * Quarantine the affected premises and the surrounding areas, if necessary, to restrict the movement of affected and exposed animals * Trace all movements of swine to and from the affected premises * Provide laboratory services to test affected and exposed animals * Euthanize or slaughter and dispose of all infected and exposed animals; dispose of exposed materials like bedding and manure * Supervise cleaning and disinfection of the affected premises * Advise and assist hog farmers in the area if their herds are susceptible to the disease or located near a quarantined area * Increase public awareness of the outbreak and control efforts through press conferences, news releases, and public service announcements * Make an onsite public information specialist available to answer questions and provide updates to the media and the public.