Scientists from around the world participated in Kansas State University’s Biosecurity Research Institute May 15-17 taking a global look at the highly contagious viral disease, African swine fever (ASF). The researchers assembled to give updates on research and in some cases, the status of ASF in their countries.
ASF has not been found in the United States, but is a serious problem in Africa and outbreaks have occurred in other countries, including Spain, Italy, Russia, and the Dominican Republic. There is no vaccine or treatment. Changes in production practices and increasing globalization have increased the risk of introducing ASF into North America and other parts of the world, according to the Center for Food Security and Public Health at Iowa State University.
“ASF is spreading in many areas of the world which means that there is an increasing threat of introduction into the United States,” said Stephen Higgs, research director of the BRI and symposium coordinator. “Something as simple as a discarded sandwich containing meat from an infected pig could be enough to cause an outbreak. Although we might be able to contain an outbreak in commercial pigs, the consequences could be devastating to our booming and highly competitive pork industry. Due to the growing numbers of feral swine that are widely distributed in the U.S., the virus could then become established here.”
Humans are not susceptible to the African swine fever virus (ASFV), but when an outbreak occurs in any region or country, the financial and physical implications can be devastating to the swine industry and those related to it. During outbreaks in Malta and the Dominican Republic, for example, the swine herds of the entire countries were completely depopulated.
The effect on a swine herd can vary depending on the strain, from near 100 percent mortality to cases of low virulence isolates that can be difficult to diagnose.
Species that can be infected include domesticated members of the pig family, as well as wild species, such as wild boars, warthogs and bush pigs, the latter species usually without clinical signs.
“We have 20 million feral pigs in Australia, so if African swine fever arrives, we might have a problem we could never get rid of,” said Martyn Jeggo, director of the Australian Animal Health Laboratory. He said Australia has a commercial swine herd of about 2.5 million head.
The disease can be transmitted by direct contact with infected animals, ticks, or indirect contact with fomites – inanimate objects or substances, such as clothing, furniture, or soap – that is capable of transmitting infectious organisms from one individual to another. Other blood-sucking insects such as mosquitoes and biting flies may also be able to mechanically transmit the virus.