What Is African Swine Fever? Symptom Identification and Prevention and Control Methods Explained

Currently, African swine fever outbreaks have drawn a great deal of public attention. Food is the first necessity of the people, and how could our dining tables be without delicious and nutritious meat? So do you know what African swine fever is? What symptoms does African swine fever present? And how should people prevent and control African swine fever?

I. African Swine Fever

African swine fever is a swine disease caused by a highly contagious filterable virus with acute, febrile characteristics, and the World Organisation for Animal Health lists it as a legally reportable animal disease. It is characterized by a short disease course and a mortality rate as high as 100%. Clinical signs include fever (reaching 40-42°C), rapid heartbeat, difficulty breathing, some coughing, serous or mucopurulent discharge from the eyes and nose, cyanosis of the skin, and obvious hemorrhage in the lymph nodes, kidneys and gastrointestinal mucosa. Under natural conditions, this disease infects only pigs, and pigs of different ages, sexes and breeds, as well as wild boars, are all susceptible. China confirmed its first case of African swine fever on August 3, 2018.

II. Symptoms of African Swine Fever

The incubation period for natural infection is 5-9 days, often shorter, while for experimental clinical infection it is 2-5 days.

1. When the disease strikes, the pig's body temperature rises to 41°C and lasts for about 4 days; death occurs 3-6 days after infection, and the body temperature drops in the 48 hours before death;

2. Sick pigs show a decrease in white blood cells, especially a predominance of lymphocyte reduction;

3. The hairless parts of the ears, nose, armpits, abdomen, perineum, tail and feet of sick pigs show clearly demarcated purple patches;

4. The larynx and epiglottis show petechial congestion and diffuse hemorrhage;

5. Necropsy shows an enlarged spleen that is black in color and brittle in texture. The lymph nodes are enlarged, brittle, fragile and hemorrhagic, resembling black blood tumors.

III. Prevention and Control of African Swine Fever

At present, no vaccine that can effectively prevent African swine fever has been developed anywhere in the world, but high temperatures and disinfectants can effectively kill the virus, so good biosafety protection on farms is the key to preventing and controlling African swine fever.

1. Strictly control the entry of people, vehicles and susceptible animals into farms, and strictly implement measures such as disinfection for people, vehicles and goods entering and leaving farms and their production areas.

2. Raise pigs in confined conditions as much as possible, adopt isolation and protection measures, and avoid contact with wild boars and soft ticks of the genus Ornithodoros as much as possible.

3. It is strictly forbidden to use swill or food waste to feed pigs.

4. Actively cooperate with local animal disease prevention and control agencies in carrying out disease monitoring and investigation, especially in cases such as vaccine immunization failure against swine fever or deaths from unknown causes, which must be reported promptly to the local veterinary department.

The above is an introduction to African swine fever, its disease symptoms and prevention and control measures. Do you understand African swine fever a little better now? In addition, African swine fever is not a "zoonosis"; it infects only pigs, not humans. So there is no need for everyone to worry or be too afraid.