While recent detections of African swine fever (ASF) in Finland’s wild boar population and classical swine fever (CSF) in Japan highlight a persistent global threat to commercial swine, U.S. producers are being urged to tighten on-farm biosecurity and focus on what they can control in their operation.
How Does ASF in Finland Impact the U.S.?
Although the recent spread of African swine fever (ASF) in Finland is discouraging, Dr. Lisa Becton, associate director of the Swine Health Information Center, says the good news in the latest Swine Disease Global Surveillance Report generated is that it’s only been detected in wild boar and not in commercial swine populations.
“This outbreak reminds us that there’s still active virus and high risk for transmission within the global wild pig population. Because the U.S. has a significant feral hog population, it is critical that producers focus on the prevention of emerging swine diseases by preventing exposure of commercial swine to feral swine,” Becton says. “If ASF ever got into that population, it would be very difficult to control, so we need to focus on actions that we can take to prevent it from entering the U.S.”
She says SHIC’s surveillance of global disease outbreaks allows pork producers to learn from what other countries are doing to mitigate or reduce exposure of commercial herds to feral pigs. Although that’s not a problem for the many producers in the U.S., others do have to mitigate this challenge.
“Reduce exposure by preventing nose-to-nose contact with wild pigs, and that includes things like removing attractants such as spilled feeds or closing doors or gates where wild pigs can get in,” she says. “Feral pigs can get into some farm setting easily, and having barriers like preventive fencing can work, but sometimes it fails. Do what you can to minimize attractants around your farm.”
New World Screwworm Update
Becton applauds the response from USDA and state animal health officials in Texas and New Mexico to manage and eliminate active cases in the U.S. She notes that ongoing control relies on active surveillance, animal inspections, and releasing sterile flies through joint efforts between U.S., Mexico and Panama COPEG.
FDA recently announced a new topical medication available for emergency or over-the-counter use to prevent screwworm infestation at wound sites. CLiK Extra (dicyclanil topical suspension) wound spray is for application on or around wounds for the prevention of New World screwworm (NWS) infestations (myiasis) in sheep, cattle, goats, swine and camelids. It is also for use in the following captured wildlife species: cervids, American bison, bighorn sheep and Sonoran pronghorn.
CLiK Extra wound spray is available over the counter for topical use on or around wounds. This Emergency Use Authorization (EUA) authorizes CLiK Extra wound spray only for prevention of NWS myiasis associated with wounds, birth and after surgical or husbandry procedures (e.g., dehorning, ear tagging, castration, tail docking, shearing), USDA reports in a release.
It is applied at the time of wound appearance or creation. If a wound is already infested, or if an infestation develops after administering the product, contact a veterinarian to discuss treatment options. Rather than killing NWS larvae, it acts as an insect growth regulator that disrupts the development of larvae and halts their life cycle before they can cause tissue damage in the host animal.
Becton points out that it carries a long 86-day withdrawal period for swine, so producers should be mindful when using it.
During a recent SHIC webinar about NWS, Jeff Weigert, an instructional associate professor and swine Extension specialist at Texas A&M University, says producers should not look for the fly itself because it is very difficult to find. Instead, producers should inspect animal wounds directly for actual infestations/maggots.
Other Global Diseases to Watch
Foreign animal disease threats such as classical swine fever (CSF) and foot and mouth disease virus (FMDV) remain globally. The detection of classical swine fever (CSF) in Japan last month confirms an ongoing risk of this disease, Becton says. FMDV continues to pose risk in other countries including a recent outbreak in Vietnam where it has not been seen in 8 years. It is important to continue to monitor for the different serotypes of the virus as this can impact control measures like vaccination.
“We know vaccine strains do not always match up with what’s circulating, so that’s something USDA is assessing when they look at our vaccine banks and antigens available,” Becton says. “It’s important to understand risk factors like vaccine mismatch, but also important to identify other risk factors such as the potential of illegal animal movements. If animals are moved that don’t have papers, don’t have inspections, or are ill when they’re moved, all of those things can contribute to disease spread.”
Global disease trends serve as a constant reminder that biosecurity is not a static checklist, but an active defense. By focusing on daily, on-farm mitigations, U.S. producers can continue to control their own risk and keep domestic herds secure against the unpredictable nature of global animal disease.
