African swine fever has been flowing around the world for a hundred years

“African Hog” has recently attracted worldwide attention. It is an animal plague originating from sub-Saharan Africa and transmitted by African swine fever virus. It can cause hemorrhagic fever in domestic and wild boar, and the infection rate and mortality rate are very high. high. Although no cases of human infection have been found, it is a deadly threat to livestock farming. African swine fever has a history of more than 100 years, especially in Europe, which has long plagued farmers and the entire industry.

Thought that “African swine fever is only spread in Africa” Intriguingly, ancient Africa did not have a pig industry, and the main farmed livestock were cattle and sheep. At the end of the 19th century, the cattle plague in the Kenyan plateau, the most developed animal husbandry in Africa, ravaged the cattle, causing a large number of cattle to die. Local farmers were forced to turn to raising pigs. In 1904, farmers who settled in the Kenyan Plateau and originated in South Asia introduced the first African pigs from the Indian Ocean island of Seychelles.

A year later, the “local white” farmers from Scotland also introduced another breeding force from the British Isles. The stronger domestic pigs and the African pig industry developed immediately. These farmers used a free-range approach in Africa, but they ignored a danger: at this time, the close relatives of domestic pigs such as giant forest pigs, warthogs and jungle pigs lived in the forests of East Africa, but not harmless to humans.

Deadly African swine fever has been spread among these “close relatives of domestic pigs”, and locals and later South Asians and European settlers know nothing about this (because they have never raised pigs before). In 1907, humans first recorded the African swine fever in domestic pigs, and local pig farmers who were caught off guard suffered heavy losses. Due to inexperience and psychological preparation, it was not until 1921 that an unnamed veterinarian first identified this as a new type of swine fever and named it “African Hog.”

Initially, people mistakenly thought that “African swine fever is only spread in Africa”. The “plague” from the colonial zone In the shadow of African swine fever, the African swine industry has developed slowly and has spread from the early northern part of East Africa to all parts of Africa. In the Portuguese colony of Mozambique, some Portuguese immigrants also began raising pigs. In 1957, part of the immigrants returned to their native land in Portugal, in view of the turbulence of local independence movements. They took everything that could be taken away, including some piglets, but inadvertently brought the African piglets out of Africa for the first time. At that time, Portugal was one of the least developed countries in Europe.

However, after dealing with animal epidemics, it was much more experienced than Africa. It quickly adopted the most simplistic treatment: all livestock in the affected areas were slaughtered and destroyed. Although this move triggered a fierce protest from the locals, it was unexpectedly effective: the epidemic disappeared. However, three years later, Portugal ushered in a second epidemic: the Portuguese colonists returning from another African colony, Angola, once again brought back piglets and African piglets during the “big move”, and this time because The protesters’ obstruction, the epidemic had spread before it was extinguished.

The first route of transmission is “pig farm transmission”. African swine fever can be indirectly transmitted by direct contact with disturbed live pigs, consumption of infected pigs, or by parasites as viral vectors. At that time, many large-scale pig farms in Europe were used to feeding livestock with artificial mixed feed containing animal bone meal. Many of these feeds came from Portugal.

At one time, France, Italy, Belgium, Malta, Italy… many pork products imported and used. The country was tossed to death. The harsh reality and the painful loss forced the southern European pig farmers to fundamentally change their pig-raising mode. The traditional free-range and simple captive methods were completely abandoned, and replaced by a fully enclosed mechanized farming method. The pigs were generally vomited “not good”, but did increase the safety factor.

“Completely closed”, strict quarantine and isolation, and the “killing” method after the outbreak of the epidemic, caused the African swine fever to spiral out in Western Europe, failing to form a major epidemic. Wild communication can’t prevent However, a “dead angle” has always existed looming: Sardinia, Italy. Sardinia is a huge island in the Mediterranean. The agricultural community here is very conservative and conservative.

It is once again infested by the mafia. It is resistant to the “modern pigs” who may take away the local people’s rice bowls. Similarly, the African swine fever epidemic here is always difficult to eliminate. Many African pig plagues have revived in Western Europe, which is caused by the “domestic sales” of Sardinian pork. It was not until the early 1990s that Sardinia gradually promoted the modern way of raising pigs, and the African swine fever epidemic became even more rare.

At that time, biologists predicted that “African swine fever has disappeared as an epidemic in Western Europe.” But they ignored the second route of transmission: field communication. African swine fever was originally infested by pigs such as giant forest pigs, warthogs, and jungle pigs in Africa, and was indirectly transmitted to domestic pigs through hosts such as parasites and ticks.

Southern Europe and Western Europe also live close relatives of domestic pigs such as wild boars, which can also be transmitted indirectly through the host and infected from infected pigs. Governments and farmers have “completely culled” on the pig farm epidemic, and “field communication” is like itching, and since African piglets are not infected with humans, people have long paid little attention to this “field communication”. In 1985, a sudden outbreak of African swine fever broke out in Belgium, and 30,000 infected pigs had to be hurriedly killed in a short time.

It was found that the epidemic was not “as usual” from the “African piglet dead end” Sardinia Instead, it is transmitted to domestic pigs through the tick from the local wild boar population. Some biologists and agricultural experts have called for “controlled culling of wild boars in the Belgian soil” to curb the spread of African swine fever, but they have been resolutely opposed by environmental groups. Fortunately, the epidemic quickly subsided, and this controversy has been put on hold for 30 years.