Bird flu – how a virus conquered the world – Insurance for Pets

All over the country, poultry are being locked up again in this country. Where did the virus actually start? And how did it spread so quickly?

At the beginning of February there were two outbreaks of H5N8 in a turkey farm with 14,000 animals in the Uckermark in Brandenburg. The whole stock was culled. In Mecklenburg-Western Pomerania in the Vorpommern-Rügen district, the virus was rampant in a fattening population of 19,700 turkeys (overview of new cases here). It was also found in animals in the Grimmen zoo after several domestic geese had died. But only those animals were culled that were too close to the dead geese.

Soon after, new cases were reported from turkey farming in Glasin and from hobby poultry farming in Gadebusch. On February 25, a new case from the Rostock district was added. In the districts of Rügen and Greifswald, compulsory stable was ordered. Infected wild birds were also found in Lower Saxony. Here, in some cases, stabling obligations were imposed, as was the case in Saxony. In Northern Thuringia, the compulsory stable was gradually lifted again after a short time in almost all districts, cities and municipalities.

In Bavaria, where the virus was detected in a dead gray goose on February 6, poultry are compulsory in some districts. In Schleswig-Holstein 1,800 animals were killed in a goose holding in the Dithmarschen district at the turn of the year.

In the meantime, further cases of avian influenza have occurred on the west coast, which is why the nationwide stable requirement, which has been in force since November 2020, should remain in place. Only in North Rhine-Westphalia there is no compulsory stable, although dead wild birds have also been discovered here.

The spread of avian influenza among wild birds in some regions was confirmed by the Friedrich Loeffler Institute (FLI) at the end of the year. According to the FLI, the number of infected wild birds had risen to around 16,000 at the end of December by the end of December. Farm animals and pets should be kept away from feeding and drinking places for wild birds, warned the consumer advice center.

The H5N8 subtype last made a name for itself in Germany in 2017, when hundreds of thousands of birds had to be killed in Central Europe. Transmission via food was previously considered unlikely. In December, however, seven employees of a poultry farm in southern Russia are said to have contracted H5N8 – with a mild course of the disease – as recently became known.

In the meantime, Agriculture Minister Julia Klöckner commissioned the Federal Institute for Animal Diseases and the University of Rostock with a study in addition to the FLI and the RKI in order to better assess the risk of infection for people. In the event of outbreaks in Germany, for example, monitoring of the people who come into contact with infected animals should be initiated as a precaution. Existing pension plans are to be adapted to current events.

In addition, the RKI recommends special precautionary and protective measures for people who have close contact with sick or dead birds before or during an outbreak of pathogenic avian influenza.

From animal-human to human-human transmission

The infected birds not only suffer from the gastrointestinal symptoms typical of avian influenza, but also from swollen wattles and sinuses. Other symptoms include constipation, bruising of the ankles and thighs. As a result of a lack of oxygen, the comb and legs turn blue. In addition, tissue damage occurs to internal organs.

Poultry died in droves from such symptoms in mid-December 1997 in Chinese markets. In the end, the authorities killed 1.5 million animals and banned imports from Chinese provinces.

What scientists had long feared soon materialized: The virus strain spread to numerous other genera. It began in Hong Kong in March 1997 when a deadly influenza epidemic struck a poultry herd at two farms. Two months later, a three-year-old boy with H5N1 died. In November, a six-year-old child was infected – and recovered. Two weeks later, a teenager and two adults became infected, and 14 more infections followed.

According to the WHO, between 2003 and 2009 around 440 people fell ill with bird flu, and 262 of them died. If the infected initially had contact with poultry, for example on farms, transmissions from person to person increased in some countries in Asia. The H5N1 patients suffered from high fever, pneumonia, inflamed airways, diarrhea, and vomiting. In some cases, multiple organ failure occurred.

In humans, the disease is often fatal: the pulmonary vessels become porous so that the protein fibrinogen can penetrate. The resulting connective tissue (fibroblast) clogs the alveoli. The backlash is an attack by cytokines, a fluid that is deposited in the lungs and on which patients drown within a few days. Heavily changed, the virus reappeared in humans in 2002. The so-called genotype Z spread almost all over Asia and Southeast Asia.

As the virus spreads across three continents, it comes into contact with locally specific combinations of host bodies. The greater the genetic and phenotypic variation in a region, the faster a human infection will develop. In China, new combinations dominated, such as the Qinghai tribe and the Fujian tribe, which prevail against local H5N1 variants. They are especially rampant in regions where animal health is not routinely monitored.

In the struggle between culture and nature

The disease is a battle between the evolution of the virus and human efforts to develop effective vaccines, scientists say. But why was H5N1 created in 1997 in southern China? And why is it so difficult to control or even prevent epidemics?

In 2008, a team led by Noel Castree from the University of Manchester evaluated studies that dealt with avian flu. Nature is being neoliberalized – through water and timber management, fishing, mining, plant and animal genetics, trading in emission rights for greenhouse gases, agriculture, breeding and using nature for pharmaceutical research purposes, the authors write.

Influenza is also a result of the exploitation of animals for multinational corporations, adds the biologist Rob Wallace. That was exactly what happened in China. Everywhere markets for live farm birds sprang up, with which many people came into contact. In the poorest countries, farms without state supervision border peri-urban slums. In this way, unchecked transmissions increase the genetic pool from which H5N1 can make use and develop specific human-related traits.

Since 1978, agricultural products have been mainly produced for Hong Kong markets. When China expanded its trade relations into the southern provinces around Hong Kong in the 1980s, a small proportion of foreign investment was already flowing into the agricultural sector.

During the 1990s, poultry production grew by an average of seven percent. The export value of processed chicken grew within four years – between 1992 and 1996 – from 6 million to 773 million US dollars.

Increasing urbanization of natural habitats

In 1997 – during the H5N1 outbreak – Guangdong was one of the provinces with the largest poultry production – with herds totaling 700 million animals. Rearing, slaughtering, processing and feed production were all organized under the same roof. A large part of foreign direct investment promoted the import of new breeding lines, propagation and modern feeding.

What was missing was adequate veterinary supervision. Since then, China has continued to expand its poultry exports. As the number of international animal transports grew and veterinary oversight was neglected, a wide variety of year-round circulating influenza serotypes developed. The « viral harvest » was transported around the world in the form of H5N1 via trade routes.

The increasing capitalist tendencies also had social consequences: Thousands of peasant families gave up agriculture and hired themselves as migrant workers, whereby they also had to give up rights such as education and other social benefits.

In the meantime, rural areas were urbanized: from 1990 to 1996, 13 percent of the agricultural area in the Guandong Pearl River Delta alone became factory sites. The often malnourished people with weakened immune systems commuted back and forth between factory work and home villages.

Hong Kong not only imported poultry, but also began shipping poultry to mainland China, along with other foods. The illegal trade in chicken meat flourished. At the time of the virus outbreak, the value of chicken smuggled into China is believed to have been more than $ 300 million a year.