STEPS TO BE TAKEN IF AFRICAN SWINE FEVER ENTERS THE U.S. PORK HERD
Apr. 15, 2019
The fear is real. African swine fever (ASF) is spreading throughout the world. The deadly virus could reach the U.S. Are we prepared?
Jack Shere, chief veterinary officer for the USDA, runs down a possible bad-case scenario and plan of action.
Let's say Farmer A has 500 sows and half are dead or dying. His local veterinarian knows that huge mortalities are a telltale sign of a virulent form of ASF. He calls the state veterinarian who immediately quarantines the farm and collects blood samples.
The state veterinarian alerts the USDA, which flies the samples to the Foreign Animal Disease Diagnostic Laboratory (FADDL) in Plum Island, New York, the only facility in the U.S. where many infectious foreign animal disease agents are studied.
"We tell our state vets, if it looks like a foreign animal disease, don't dink around with it at your lab," says Shere. "If it looks like the real deal, if there are massive die-offs, we fly the samples to FADDL. We don't mess around."
A dual set of samples may be tested at a state lab, but "confirmation on any foreign animal disease has to be done at a federal lab," explains Shere.
If ASF is confirmed after running the test several times at Plum Island, Shere is alerted any hour of the day or night. "They would tell me, Dr. Shere, we have a positive. I would ask, 'Are you sure? How many times did you run it?' Once I know it's positive I go up my chain of command to the administrator, the undersecretary, and the Secretary [of Agriculture, Sonny Perdue]."
Meanwhile, the trace work at Farmer A's farm has begun. "We have to find out what animals have come on the farm, what's left the farm, what sales or purchases have gone on. We get a list of those and we start tracing them," says Shere.
Other state veterinarians are alerted. They make farm visits to see if there are any clinical signs of disease. "It's shoe leather epidemiology," says Shere. "If there are signs at another location, they test that farm and quarantine. And on and on."
As this is going on, the results are reported up the chain and the USDA is mapping and tracking the disease in its computer system. Decisions are being made on what needs to happen next. Shere says he has been told that if ASF breaks in the U.S., "it will be in 22 states in a few days because of the way we move pigs. That's scary."
If the disease is deemed widespread, a 72-hour shutdown is put into place. Nothing moves. "Animals in transit will reach their point of destination, or they will be turned around and sent back to their point of origin, depending on the state," explains Shere.
Three days is all they have, he says, "because if you shut things down longer than that, you start getting into animal welfare issues. We shut down for 72 hours and see if we can get a handle on things."
The Hardest Part
Meanwhile, all the pigs at Farmer A's are being euthanized. Same for any other confirmed positive farms.
"There is no vaccine for ASF," says Shere. "We are killing animals. That process starts immediately. The way you stop a virus that you don't have a vaccine to control is you euthanize animals."
With euthanasia comes disposal. What are you going to do with all those dead animals? Each state has a plan.
The federal veterinarians will roll into each state with an Incident Management Team, says Shere. "We ask them about their rules. What is their plan on disposal? How are you going to kill the pigs? Can we burn them? All those things we have to look at. If they don't have a state task force big enough to control it, we are bringing more people in."
The number one goal is eradicating the disease, he says. "Stomp it out. We want to get rid of it, if we can."
That is no easy feat, as China has found out since August 2018. "ASF is endemic in China, don't kid yourself," says Shere. "It's all over. They are going to live with that. They are trying to get rid of it, but it's endemic and it's spreading to other countries surrounding China.
"We would try to eradicate it. If we can't, then it becomes endemic. You go farm by farm and you test. If pigs are positive, they die. That is a bad scenario."
All this time, of course, pork exports out of the U.S. are shut down. "No one is going to accept anything from us until we determine where the disease is," says Shere. "Canada and Mexico would regionalize us, because they have the same things at stake as we do. If they get the disease, we would regionalize them."
The Regionalization Evaluation Services evaluates the animal health status of foreign regions (zones) and the risk of disease introduction via commodities for import into the U.S.
The USDA would have to prove the disease locations and where it isn't, and "show that we have a good traceability system so we can move our animals," says Shere. "In a nutshell, that's what happens in a foreign animal disease outbreak."