The first African swine fever (ASF) outbreak in China was reported on August 3, 2018. The epidemic has been reported in 14 countries across Asia, and only Taiwan and Japan have not reported the outbreak in East Asia. Although ASF does not infect humans, its virus can infect pigs of all breeds and ages. The acute infection morbidity and mortality rate are as high as 100%. Currently, there is still a lack of vaccines and antiviral drugs to prevent and treat. Culling is the only way to treat this disease, which seriously threatens the pig industry. This report is based on information related to ASF on the official website of the World Organization for Animal Health (OIE) and the Bureau of Animal and Plant Health Inspection and Quarantine (BAPHIQ) of the Council of Agriculture, Executive Yuan. It outlines Taiwan’s current border and domestic quarantine measures in response to ASF as a reference for those interested in this topic.
Keywords: African swine fever (ASF), Quarantine measures
African swine fever (ASF) is a highly contagious hemorrhagic viral disease associated with high mortality in domestic and wild pigs. The disease is caused by the African swine fever virus (ASFV). ASFV is a double-stranded DNA virus, which is the only member of the family Asfarvidae, genus Asfivirus. The first ASF outbreak case was reported from infecting domestic pigs from Kenya, Africa, in 1921. In recent years, at the beginning of 2017, an ASF epidemic has also been documented in Irkutsk, far eastern Russia. After that, the epidemics were also reported near the borders of China, which indicates that ASFV has extraordinary transcontinental spread capabilities. China reported the first ASF outbreak case on August 3, 2018. Since then, the distribution of ASF has spread rapidly, resulting in several outbreaks in China's different provinces. The source of the ASFV spread to China is still unclear. It is worth noting that there is still a lack of vaccines and antiviral drugs against ASFV infection.
Taiwan is an island located in the South China Sea, close to mainland China. The main island of Taiwan is surrounded by several islands, including Matsu, Kinmen, Penghu, Green, and Orchid Island. In recent years, the frequency and amount of economic activities such as trade and business travel between China and Taiwan have increased. Due to Taiwan has more than 5 million pigs, local pig farmers are worried about the spread of ASF from neighboring countries such as Vietnam, China, Mongolia, and South Korea, all of which have confirmed pigs infected with the ASF virus. Although ASF has never been reported in Taiwan, ASFV can easily be introduced into our country in various ways. With the introduction of pork products contaminated with ASFVs brought by travelers and imported ASFV-infected pigs, the risk of introducing ASF into Taiwan may increase. Pork products contaminated with ASFV are currently the leading risk factor for the spread of the disease. The Bureau of Animal and Plant Health Inspection and Quarantine (BAPHIQ) announced that ASFV was detected for the first time in sausages from China carried by travelers to Kinmen on October 31, 2018. Therefore, Taiwan has strictly monitored pork products confiscated at airports and ports by passengers coming from countries affected by ASF since October 2018. However, strict border controls still can’t prevent all risks. A dead pig was washed ashore on Kinmen Island on December 31, 2018. This dead pig was confirmed as a positive case of ASF.
The Food and Agriculture Organization of the United Nations (FAO) announced that ASFV is likely to spread from China to other countries of Asia. Recently, Kim et al. (2019) revealed that ASFV was found in pork products brought into South Korea by travelers from China. The results of such investigations indicate that travelers may be a significant risk factor and pose a potential threat by bringing pork products from ASF outbreak areas. In addition, the research also found out that the food waste used for pig feeding contains pork and is contaminated with ASFV, which are potential sources of persistent ASF outbreaks in endemic countries. In summary, this report outlines Taiwan’s official response policies against the ASFV outbreak. Travelers who privately bring pork products from countries infected with ASFV are considered a potential threat to the introduction and spread of ASFV in uninfected areas. It should be urgently required to conduct strict border inspections on confiscated products to control and prevent ASFV from invading Taiwan and spreading to other Asian countries.
Prevent the Invasion of ASF to Taiwan (Specificmeasures of central and local authorities)
- Establish an emergency operations center for ASF: The Executive Yuan established the Central African Swine Fever Emergency Operations Center on December 18, 2018, to comprehensively analyze the possible intrusion gaps of the epidemic and prevent it immediately. At the same time, strengthen the inventory of various epidemic prevention and preparation work with local governments. The counties and cities had also completed establishing the ASF emergency operations centers under their jurisdiction on January 4, 2019.
- Sampling for virus monitoring (including disposing of travelers or carrying in violation of regulations): In order to establish an early warning mechanism, the early warning monitoring and sampling for illegally smuggled products, domestic disposed dead pigs, the dead pig which was found on the coast, rendering plants, slaughterhouses, etc., are sent to the Animal Health Research Institute (AHRI) for testing, and the testing results will be announced. In addition, samples of imported fishmeal products from China, Vietnam, Thailand, the Philippines, and India were sent for testing to check whether they contained pig-derived ingredients and ASFV nucleic acid. Risk assessment and management references were made based on the testing results. In addition to blocking epidemics at the border, domestic prevention and deployment are not slack. The Council of Agriculture has stockpiled relevant disease prevention materials while continuing to increase ASF testing capacity. AHRI combines the laboratories of the department of veterinary medicine of 4 universities (including National Taiwan University, National Chung Hsing University, National Chiayi University, and National Pingtung University of Science and Technology), as well as the College of Medicine of National Cheng Kung University and the Agricultural Technology Research Institute (ATRI) to ensure the quality of diagnosis through proficiency testing four times a year. At present, the maximum testing quantity per day has been expanded to 1,900 samples.
Prevent the Invasion of ASF to Taiwan (Specific measures for border quarantine)
- Strengthen border quarantine: Prevent travelers from bringing meat products into Taiwan. Livestock meat is a high-risk product for the spread of ASF. Therefore, the airports and ports (including fishing harbor) strengthen the inspection of passenger luggage, online shopping express goods, international parcels, etc., through X-ray machines, increasing the frequency of quarantine detector dog and personnel inspections. Especially for passengers arriving from areas with a high risk of ASF (such as China, Hong Kong, Macau, Vietnam, Cambodia, Laos, Myanmar, South Korea, Russia, etc.), the measure of using the X-ray to inspect the carry-on baggage for preventing passengers from entering Taiwan with meat; meanwhile, strengthen smuggling investigations and prevent the smuggling of meat products into Taiwan.
- Strengthen the promotion of passengers not to bring meat products back to Taiwan: Promote through broadcast before the arrival of airplanes and ships, and carry out relevant propaganda on the TV wall, lightbox, and news ticker of the arrival and departure hall. Produced promotional leaflets in 7 languages including Chinese, English, Thai, Vietnamese, Indian, Japanese and Korean, advocating that “If those who go to livestock farms in countries affected by animal infectious diseases within 14 days before entering Taiwan, should change their clothes, shower and thoroughly disinfect them after entering Taiwan, and can only enter the livestock farms after 7 days.”
Prevent the Invasion of ASF to Taiwan (Specific measures for domestic epidemic prevention)
- Taiwan government implements the three-way control mechanism of the source: Strengthen the inspection and guidance work of livestock farms, meat markets, and slaughterhouses. The measures include that:
- Before cloven-hoofed animals enter the meat market and slaughterhouses, owners must submit the "Animal Health Declaration;”
- The animal transporting vehicles must be cleaned and disinfected under the supervision of epidemic prevention personnel before leaving the meat market; and
- Slaughter inspection veterinarians shall strengthen the implementation of pre-and post-slaughter inspections.
- Improve the safety of food wastes for pig raising and guide the transformation of food waste-based pig farmers: Food wastes must be steamed at 90 degrees Celsius for at least 1 hour to kill the ASFV. Therefore, the government actively counseled pig farms that do not have food waste steaming equipment to use feed to raise pigs. The COA also provides several complementary measures such as feed subsidies, technical consultations, or voluntary exit subsidies, which the local government implements. Furthermore, local governments shall strengthen inspections and audits during the transition period and strictly supervise the steam cooking of food waste to prevent the transmission route of the disease.
- Live pig and carcass shipping vehicles are mandatory to install GPS: It is compulsory to install GPS on the shipping vehicles of live pigs, carcasses, offal, and their cuts. Use technology to track the flow of pigs and fresh pork timely. Also, combine the needs of animal husbandry production, transportation, slaughtering, disease prevention, food safety, etc., to trace the source farms and the flow of meat, as well as monitor and control the movement of pigs when the outbreak occurs, to comprehensively prevent the blind spots of the spread of ASF.
- Strengthen the re-education of veterinarians and the education promotion of pig farmers: Strengthen the training of veterinarian professionals related to ASF to increase awareness of the epidemic. In addition, the animal disease prevention agency continually conducts clinical visits to the farms, counseling pig farmers to increase their vigilance and implement biosafety measures and epidemic report.
- Raise the awareness of epidemic prevention among the whole people: Use a variety of channels and multiple languages to strengthen the publicity that people or travelers are prohibited from bringing meat products back to Taiwan or buying meat products online to send to Taiwan. Avoid visiting livestock farms in countries with ASF to prevent the spread of the epidemic and harm the livestock industry. In addition, an exclusive webpage for African swine fever is set up to provide the current status of the international epidemic situation, instructions for inspection and quarantine, and a hotline for the epidemic report, etc.
- Implement epidemic prevention drills and strengthen emergency response operations: Continuing epidemic prevention drills to improve the familiarity of epidemic prevention personnel in handling epidemics and reduce the damage caused to the industry when the epidemic occurs. All county and city governments have completed African swine fever prevention drills.
At present, the global ASF epidemic is still severe. So far in 2021, in Asia, ASF outbreaks have expanded to Malaysia and Bhutan. Moreover, China, South Korea, Vietnam, and the Philippines still continue to report ASF outbreak cases. For that reason, the Taiwan government strictly implements various epidemic prevention measures to prevent the ASF epidemic from entering Taiwan in an all-around way to protect the Taiwanese pig industry.
African Swine Fever-OIE World Organization for Animal Health. World organization for animal health; 2019. Available from: http://www.oie.int/en/animalhealth-in-the-world/animal-diseases/african-swinefever.
Hyun-Joo Kim, Min-Jung Lee, Soo-Kyoung Lee, Da-young Kim, Sang-Ji Seo, Hae-Eun Kang, and Hyang-Mi Nam. 2019. African Swine Fever Virus in Pork Brought into South Korea by Travelers from China, August 2018. DOI: https://doi.org/10.3201/eid2506.181684.
Taiwan, Bureau of animal and plant health inspection and quarantine, Council of Agriculture Executive Yuan, Taiwan; 2019. Available from: https:// https://asf.baphiq.gov.tw/