Read the passage carefully. 1. African swine fever is one of the most dangerous diseases of swine. Since its first identification in East Africa in the early 1900s, African swine fever (ASF) spread to Kenya in the 1920s; transcontinental outbreaks in Europe and South America in the 1960s and in Georgia (Caucasus) in 2007 led to subsequent transmission to neighboring countries east of Georgia. Along with the outbreaks in the eastern territory of the Russian Federation, acute ASF outbreaks were ...

Read the passage carefully. 1. African swine fever is one of the most dangerous diseases of swine. Since its first identification in East Africa in the early 1900s, African swine fever (ASF) spread to Kenya in the 1920s; transcontinental outbreaks in Europe and South America in the 1960s and in Georgia (Caucasus) in 2007 led to subsequent transmission to neighboring countries east of Georgia. Along with the outbreaks in the eastern territory of the Russian Federation, acute ASF outbreaks were reported in China in 2018. 2. During January 15–31, 2019, a disease outbreak at a family-owned backyard pig farm in Hung Yen Province,Vietnam, was reported. The farm, about 50 km from Hanoi and 250 km from the China border, housed 20 sows. In the early stage of the outbreak, 1 piglet and 1 sow exhibited marked redness all over the body, conjunctivitis, and hemorrhagic diarrhea. Breeding gilts demonstrated anorexia, cyanosis, and fever (>40.5°C). 3. Since ASF was first recorded in Vietnam on February 1, 2019, the country has culled more than 85,000 pigs, according to the official reports. However, it has been promptly controlled thanks to the timely response of the Government; Prime Minister Nguyen Xuan Phuc; the Ministry of Agriculture and Rural Development (MARD); and other relevant ministries, agencies, and localities. Since then, a lot of families have quitted pig farming. 4. ASF is a fatal animal disease affecting pigs and wild boars with up to 100 percent mortality, and subsequently damaging trade and causing global economic losses. The ASF virus does not affect humans. The only known preventative measure is a mass cull of infected livestock. The disease spreads by contact between infected pigs or other wild animals and can inflict massive economic damage on farms. Choose an option (A, B, C or D) that best answers each question.

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