The Animal Health section provides resources, factsheets and backgrounders on FMD, BSE, Animal Anthrax, Pseudorabies, Trichinae, Swine Fever and Hepatitis E.
Also see the World Animal Health Information Database.
Foot-and-mouth disease (FMD) is a highly contagious virus and can be spread by movement of infected animals, movement of contaminated vehicles, and by contaminated facilities used to hold animals. There have been no FMD cases in the United States since 1929. Despite a recent devastating outbreak in Britain in 2001, this highly contagious viral disease is rare in industrialized countries but endemic in developing countries.
Bovine spongiform encephalopathy (BSE), inaccurately called Mad Cow Disease, is a progressive, fatal disease of the nervous system of cattle, belonging to the group of disorders known as transmissible spongiform encephalopathies (TSE), which include scrapie in sheep and chronic wasting disease in deer and elk. The cause of BSE is still being debated, but it has been linked to an abnormal protein called a prion. There is no treatment or vaccine currently available for the disease. It is not contagious.
A single Holstein dairy cow became the first confirmed case of BSE in the United States. The U.S. Department of Agriculture (USDA) announced the suspected case Dec. 23, 2003, and concluded that one case of the disease had occurred in a Canadian-born animal in Washington State.
A second U.S. BSE case was announced on June 24, 2005. The animal, a 12-year-old Texas cow destined for pet food, was never in the food chain and ultimately incinerated.
Anthrax, a disease of mammals and humans, is caused by a spore-forming bacterium called Bacillus anthracis. Anthrax has an almost worldwide distribution and is a zoonotic disease, meaning it may spread from animals to humans. All mammals appear to be susceptible to anthrax to some degree, but ruminants such as cattle, sheep, and goats are the most susceptible and commonly affected, followed by horses, and then hogs.
Pseudorabies virus (PRV), also known as Aujeszky’s disease, is a disease of hogs that can also affect cattle, horses, dogs, cats, sheep and goats. PRV is an extremely contagious herpesvirus that causes reproductive problems, including abortion, stillbirths and even deaths in breeding and finishing hogs..
Trichinella spiralis (Trichina) has a long-standing association with pork products, not only in the U.S. but also around the world. The common belief that pork must be cooked thoroughly largely arises from fear of this parasite, which is killed by thorough cooking.
Pork: Swine Fever/Hog Cholera
Hog cholera/swine fever is a highly contagious viral disease of hogs that occurs in an acute, a subacute, a chronic, or a persistent form. In the acute form, the disease is characterized by high fever, severe lethargy, multiple superficial and internal hemorrhages, and high morbidity and mortality. In the chronic form, the signs of listlessness, loss of appetite, and fever are less severe than in the acute form, and recovery is occasionally seen in mature animals. Transplacental infection with viral strains of low virulence often results in persistently infected piglets, which constitute a major cause of virus dissemination to noninfected farms.
Pork: Hepatitis E
Hepatitis E virus is the primary cause of enterically-transmitted, non-A, non-B, acute hepatitis in humans in several developing countries. The mode of HEV transmission is thought to be mainly by fecal-oral route and outbreaks in humans are usually associated with consumption of drinking water contaminated by feces. The mortality rate due to HEV infection in humans is typically less than 1 percent; however, mortality rates of nearly 20 percent have been reported in infected pregnant women in developing countries of Asia and Africa. Attempts to reproduce fulminant hepatitis E in pregnant rhesus monkeys (Tsarev et al, 1995) and pregnant sows (Thacker et al, unpublished) were unsuccessful. HEV-induced disease is endemic in many developing countries particularly in Africa and Asia. Hepatitis E virus-induced disease is considered sporadic in humans in industrialized countries such as the U.S. Resources, backgrounder and factsheet are currently under construction and will be available soon.