December 29, 2019

African Swine Fever Update

African swine fever: FAO’s chief veterinarian shares what we've learned so far

With so many African swine fever (ASF) outbreaks in the news, it’s hard to picture the disease slowing down any time soon. Juan Lubroth, the chief veterinary officer at the U.N. Food and Agriculture Organization (FAO), recently suggested that a lot can be learned from this year’s outbreaks to help producers in the year ahead.

In a speech to the U.S. Animal Health Association, Lubroth laid out the challenges ASF poses to nutrition and the global economy. He also described the tools—both effective and over-hyped—in the fight against ASF.

One major concern for the FAO is the transmission of ASF along transport routes. Because the disease can spread through contaminated pork products, Lubroth said smuggled meat is a leading way to introduce the virus to new countries. The disease is also spread by ticks, so feral swine are becoming vectors of the disease in many places. There have been two confirmed outbreaks in wild boars tested in China so far.

Lubroth said the FAO is particularly concerned with pig production in China, where around 67 percent of swine are housed on small family farms. While this widespread “backyard” production helps meet the country’s demand for animal protein, it makes it harder to monitor and control the spread of ASF.

Lubroth added that culling/depopulation to control ASF outbreaks could have economic implications beyond just pork products. He said the smaller herd sizes means less demand for corn and soy products in animal feed. “Exports of soy and corn will decline, creating price and market disruption,” he said.

So, what can be done? Unfortunately, Lubroth said ASF vaccines currently available in China have not been rigorously tested or found effective. “They do not meet international standards and can exacerbate the problem,” he said. A consortium of international scientists has been established to develop an effective vaccine, but so far, the virus’s complicated molecular structure has made it challenging to immunize against.

There are still ways to control the disease, Lubroth emphasized. The FAO is supporting training for more experts in ASF epidemiology, lab methods, collection and identification, and diagnosis. He said a pocket-held genetic testing kit (PCR test) has worked “very well” for detecting the disease.

Lubroth’s speech came as many more countries report ASF outbreaks. In FAO’s Dec. 12 ASF situation in Asia update, the organization reports that 10 percent of Mongolia’s swine population has died or been destroyed due to ASF since the beginning of the year. In the Philippines, ASF was first detected in July 2019 and there have been 24 outbreaks since then, and in Indonesia, ASF was officially confirmed on Dec. 12. Read the full report

Meanwhile, in China, frozen pork has reportedly been liquidated for ASF testing and all stores that tested positive have been destroyed. In Australia, officials have announced that 22 percent of smuggled pork products confiscated at airports are positive for the virus, according to Feedstuffs.

“For American farmers, this means not only putting safeguards at our borders but also supporting efforts to reduce the amount of virus growing beyond our borders that can possibly enter the United States,” writes John Deen, University of Minnesota College of Veterinary Medicine. “The risk of herd infection is dependent on an understanding of broad exposures such as feed and smuggled pork products and the level of risk the industry can accept.”

Read more:

View Dr. Lubroth’s keynote presentation