by Sally Colby

If you keep a couple of sows and sell meat from your farm or at a farmers market, does the health status of pigs in the Dominican Republic (DR) and Haiti matter?

Veterinarian Dr. Jack Shere said anyone who has pigs should be concerned about pig health in other countries, especially those close to U.S. shores. Shere serves as USDA Associate Administrator for Veterinary Services and heads up USDA’s efforts to keep African swine fever (ASF) out of the U.S.

Shere spoke at the recent Global Hog Industry Virtual Conference about enhanced surveillance testing and response preparations currently underway in the U.S. and Haiti, DR, Puerto Rico and the U.S. Virgin Islands.

“It’s a devastating economic disease and will affect all of the swine industry and cost millions of dollars in production and trade,” said Shere, outlining the risks of ASF hitting the U.S. “It will have multiple economic impacts internationally and domestically, including an immediate halt to U.S. exports of pork and pork products.”

Shere said 28% of current U.S. hog production (pork and pork products) is exported. “Imagine the backup of all that pork and production, the backup in the inventory and the widespread disruption this would cause as well as employment losses as we begin to try to eradicate this disease and eliminate it from the U.S.,” he said. “Preliminary estimates are as much as $15 billion in losses to the pork industry would occur based on a two-year scenario.”

ASF broke out in China in 2018 and is already widespread throughout Asia. Mortality can approach 100% depending on the virus strain. There’s currently no treatment or vaccine, although researchers are working on one. Since January 2020, ASF has been reported in 35 countries and has affected more than 1.8 million animals. Shere said the only way to stop the disease is to depopulate affected animals and any exposed swine in affected herds.

One effort to keep the U.S. pork supply safe began with a working relationship with the DR to conduct surveillance for avian influenza and Newcastle disease, two highly contagious poultry diseases. Since lab facilities were already in place, the DR offered to begin ASF surveillance in 2019. In July 2021, ASF was confirmed near the Haitian border. Shere said it was known that Haiti and the DR moved pigs back and forth across the border, so there was concern that Haiti either was infected or could become infected. The U.S. petitioned Haiti to begin sampling, and by September 2021, ASF was confirmed in Haiti.

Given how quickly ASF spread in Asia and with only 700 miles between the DR and the U.S., concern for the U.S. pork population grew. Shere said APHIS epidemiologists and technical experts began on-the-ground work immediately after infection was confirmed in the DR and have been there since.

“We began outreach and communications throughout the U.S., especially targeting Puerto Rico and the U.S. Virgin Islands because it’s only 60 miles across the water to Puerto Rico from the DR,” said Shere. “We were also concerned about feral swine in Puerto Rico and the U.S. Virgin Islands – the potential introduction of ASF into that population would be devastating and the start of limitations of U.S. trade. We increased our domestic surveillance and testing and enhanced inspection at airports leaving Puerto Rico, the U.S. mainland, the DR and Haiti.”

The U.S. is assisting the DR with response efforts, including providing training in developing an Incident Command System (ICS). Lab support, building surveillance plans, depopulation plans and indemnification are also being developed.

Shere said as of now, all provinces in the DR and Haiti are infected. “Our response has been difficult because of an unstable government and security issues,” he said. “We are working closely with Haiti and in training their lab personnel.” The U.S. will send technicians to the DR so DR lab personnel can learn the processes and perform the same ASF tests as the U.S.

One significant aspect of the plan is developing a buffer zone between the DR and Haiti. “There has to be an island-wide approach to eradication of ASF,” said Shere, adding that the DR and Haiti are cooperating on this aspect. “The buffer zone is the area along the border where they agree to have no pigs so if one country eradicates faster than the other, that country will have a buffer zone in place to remain negative.”

Several measures are in place to prevent ASF from entering the U.S. “We’ve always had in place restrictions on the DR and Haiti in regard to pork and pork products because of classical swine fever which they’ve had since the 1960s,” said Shere. “Because ASF is there, we’ve put other mitigations in place. Feral swine surveillance in the U.S. happened almost immediately after the diagnosis of ASF in the DR and Haiti.” Shere added that efforts to eliminate feral swine have been effective, thanks to cameras and detector dogs aiding in locating feral populations. Current surveillance involves eliminating ferals as they’re reported.

Since the feeding of cooked garbage is allowed in Puerto Rico, all swine are under slaughter surveillance. “We’ve enhanced communications with Puerto Rico on the impact should ASF reach the territories or the mainland,” said Shere. “We are educating producers and others on good biosecurity practices. We’ve alerted all residents to report any feral swine and discourage them from releasing those feral swine. We are informing travelers about what they can and can’t take to the mainland.” An ongoing educational effort in both digital and print media is aimed at travelers and producers in Puerto Rico and the U.S. Virgin Islands.

“There is a pre-departure program at about 36 of our ports and airports,” said Shere. “We’re working closely with customs and Border Patrol. We’ve employed additional swine canine teams and are training 34 detector dog teams to deploy in the DR to oversee domestic flights from the DR to the U.S.”

A relatively new measure is establishing an OIE (World Organisation for Animal Health) Protection Zone for Puerto Rico and U.S. Virgin Islands. This will be similar to buffer zones and will help to maintain the current health status of mainland U.S. in the event ASF is detected in either location.

A new ASF vaccine, developed by ARS, is being tested in Haiti. Shere said a vaccine isn’t the answer yet but it shows promise. Before it’s available, the vaccine must undergo safety and efficacy trials as well as virulence testing, which could take up to two years.

One ongoing challenge is people in the U.S., Puerto Rico and Haiti who keep backyard pigs. “These pigs can easily get ASF,” said Shere. “In some areas of DR and Haiti, some of these swine roam freely so there’s cross-communication with other pigs from other farms.” Shere said ASF is no longer an emergency in these countries – it’s endemic and will require an extensive testing and surveillance program.

“Every time we think we have things under control, something else comes up that we could be doing,” said Shere.