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Since it first appeared in China in 2018, African Swine Flu has spread across the continent with great speed. It has been laying waste to large swaths of pig populations across Asia. It doesn’t infect humans, so it’s not a food-safety issue. However, the outbreak is having serious economic consequences.
A recent report by Rabobank indicated that China’s pork production has experienced significant losses. China’s pork production is projected to fall by 10% to 15% in 2020. That is on top of a 25% drop in 2019. This year alone, the country’s pig herd fell by half in the first eight months, and will likely shrink by 55% by year end, the report said. The knock-on effect extends beyond pigs and into other sectors in the agriculture industry. According to Rabobank, “China’s total consumption of animal feed such as soy will drop by 17% in 2019 due to the decline in hogs, according to Rabobank.” (SOURCE: CNBC)
The virus responsible for African Swine Fever is a large DNA virus of the Asfarviridae family. It is a large and complex DNA virus with multiple outer layers and numerous mechanisms aimed to avoid an immune reaction in the host pig. There is therefore little likely value in development of a killed or subunit vaccine approach for ASF control. Strategies to develop a suitable live attenuated vaccine have not yet been successful. (SOURCE: ASF hits backyard farms in the Philippines.)
It is believed to be related to a soft tick virus that infects several types of wild swine and to have emerged globally around 1700. (SOURCE: Wikipedia) ASF is a transboundary animal disease (TAD) can be spread by live or dead pigs, domestic or wild, and pork products; furthermore, transmission can also occur via contaminated feed and fomites (non-living objects) such as shoes, clothes, vehicles, knives, equipment etc., due to the high environmental resistance of ASF virus. (SOURCE: African Swine Fever)
Since 2018, the latest outbreak has spread rapidly across Southeast Asia. Thailand, Myanmar, Cambodia, and Laos have reported outbreaks. However, Vietnam and the Philippines are experiencing the most dramatic impacts. In Vietnam alone, there are over 6,000 ongoing outbreaks. Meanwhile, in the Philippines, the disease has spread rapidly among small backyard farmers, especially among suburban growers. The government has been slow to move when initial signs of infections appeared, wasting valuable time.
The lastest OIE African Swine Fever situation report for the time period of September 13-16 paints a grim picture. “In this period, 355 new outbreaks were notified. The total of ongoing ASF outbreaks worldwide is now 9 297. In the previous report, 344 were notified as new, while 8 239 outbreaks were ongoing.” (SOURCE: OIE African Swine Fever Current Status Report)
A warning sign in Tokyo Haneda Airport regarding the Chinese outbreak
A look at previous African Swine Fever outbreaks is instructive. Historically, outbreaks have been reported in Africa and parts of Europe, South America, and the Caribbean. More recently (since 2007) the disease has been reported in multiple countries across Africa, Asia and Europe, in both domestic and wild pigs. (SOURCE: OIE) Europe (esp.Belgium and Poland), Russia, and Africa have all experienced significant outbreaks and continue to do so. According to the World Organization for Animal Health, “ASF has never been reported in Oceania, and it was eradicated in the Americas in the ‘90s . Since 2016, 24% of the reporting countries and territories (48/200) have reported the disease as present2 . In Europe, the disease occurred for the first time in: Moldova in September 2016, then in June 2017 in Czech Republic, followed by Romania in July 2017 and more recently in Hungary, and Bulgaria, in April and August 2018 respectively. A recurrence of the disease in wild boars has been reported in Belgium in September 2018 (last event occurred and was resolved in 1985).” (SOURCE: OIE African Swine Fever Global Report)
There are no vaccines or treatments for African Swine Fever infections. The key to controlling outbreaks relies on depopulation of affected farms and prevention of new cases via strict biosecurity. ASF virus is mostly spread via contact with infected pigs (including wild boars) or pig materials, such as pork meat or offal products. (SOURCE: ASF hits backyard farms in the Philippines) Pig products, freshly prepared or processed and packaged, that come from infected pigs can also spread the disease, making it difficult to track when crossing borders. To date, the spread of ASF has been tempered but is a far cry from being kept in check.
Chinese pork vendor during 2018 outbreak
That is not good news.
With no end in sight, the current global African Swine Fever has farmers on edge. Uninfected countries are ultra-vigilant about pork products entering their borders. According to Kevin Paap, President of the Minnesota Farm Bureau, it is one of their biggest worries.
“It’s not a food safety issue, but it’s a very important agricultural issue not only for livestock, but for those that raise corn and soybeans,” Paap said. “From a U.S. perspective, our number one goal is prevention. There’s no treatment, there’s currently no vaccine for it, and it’s certainly very deadly. Prevention is the number one thing for keeping it out of here.”
Infected countries have had to contain the infections while also making up for the sudden shortage of hogs. In the second case, Chinese farmers have devised a stop-gap solution. Breeding massive pigs almost the size cattle. (SOURCE: SCMP)
IMAGE SOURCE: Creative Commons