In February 2024, the governmental veterinarians in the Czech Republic, which was achieved in the outbreak of bird influenza themselves in the midst of a confusing case.
H5N1, the nursing virus was destroying a herd of chicken on a very safe farm, home to the reproductive program that produced hybrid birds with feathers and eggs specially colored. A close facility owned by the company itself also witnessed its chicken.
How did the virus enter? The facilities were modern. The water on the chicken farms was filtered, and provided by their wells. The chicken homes had giant fans that created one direction in one direction through the barns. The elbow was surrounded by strong fencing and well -maintained them. The wild animals kept. Employees were not even allowed to keep their chicken at home.
The investigation of the researchers led to the conclusion that this particular condition included a distinct set of “correct” conditions that allowed the virus to explode on the chicken farm through the wind.
Wild birds that carry influenza viruses in their courage and climb in their tube are the main way in which H5N1 was presented on farms. However, experts say that the spread of windflowed influenza has been suspected before.
“The full idea that it is likely to be preserved on the wind was present for a while,” said Dr. Richard Web, who directs an animal influenza study center.
He said: “It is very difficult to measure in fact, to get the final data to say yes or no.”
Webby was not involved in the new study, but he said he was in contact with a veterinarian in California who believed that Wind had played a role in the recent spread of H5N1 among some herds of livestock in the middle of the valley.
But even if he is moving through the air, he said, this does not necessarily make bird flu a greater threat to people.
For one reason, the current versions of the H5N1 virus that affect animals do not look very good in human injury. The more the virus, the greater the opportunities to refine and improve in storming human cells, but at the present time, there is no sign that it made this jump until the causes of human diseases are completely.
For another, it takes just a small amount of viruses to make birds sick, and it may take much to infection. The particles, even viruses, are dispersed in the air, which means that any virus in the wind is likely to be present in only small quantities.
How the virus jumped between the farmer
In the case of the chicken farm in the Czech Republic, the only idea of scientists came about the origins of the outbreak of a farm near the fat that, a week ago, an enosa of birds through its herds.
The Duck farm, which includes 50,000 birds, was completely different from the chicken facility. It was near a lake hosted the wild ducks. The ducks are kept in the natural ventilation buildings and a basic level of biological security – precautions taken to protect animals on the farm.
The infection path in the duck farm seemed completely different from what he played with chicken.
The bird flu has swept through the duck houses such as the wildfire. On February 4, on the first day of the outbreak of the disease, 800 ducks died. Within two days, 5000 died. On February 7 and 9, the entire herd was extracted to control the spread of infection and prevent greater suffering for birds.
The chicken in the reproduction facility was also different in another way as well: they slowly fell ill. For a week, they gradually stopped eating and drinking with the same extent, and the owners of the farms noted that some birds were dying, most of which were near the air eating openings.
In the end, the infection spread to each of the barns in the reproductive facility and another barn on the second site. It lost thousands of birds, including critical reproduction stocks.
Government veterinary investigators gathered samples of viruses that hit ducks and chicken in the reproductive and chicken facility on the second farm to find out what they could learn.
Three H5N1 strains of the duck farm were genetically identical with the breeds in the birds that were first fell ill in each farm, indicating that the duck farm was the source of the outbreak of chicken.
But how? The duck farm was about 5 miles west of chicken facilities, and investigators were unable to find any material links between the two. None of the people who worked on the duck farm went to chicken farms; Even the contractors who stopped supplies or came to collect the waste were different. Investigators said they had excluded any human bonds between the farmer.
There were no major water bodies near the chicken farm, which they removed away from the idea that wild birds may have been carried in the influenza virus.
The weather carries an idea
After that, the researchers examined the weather patterns during the week that fell ill. There was a fixed breeze from the West. There was a large -scale cloud cover, which would have prevented ultraviolet murder light from the sun. The temperature was cold but does not freeze, between 40 and 50 degrees, and viruses love cold air.
In other words, the ideal conditions for transmitting the virus and allowing it to survive on a long journey.
After exploring all possibilities, the spread of WindBorne was the best in this case.
“I think that under certain specific circumstances, the spread of the wind influenza can occur on the wind,” he said.
Czech researchers published their studies As preprintBefore reviewing the peers.
Webby said that the virus molecules can also connect to something greater, such as Dander of ducks, and this has allowed them to travel so far.
The authors of the study have not tried to take air samples near ducks or chicken for viruses, and they notice that the studies of previous air samples in and around pigs and poultry homes have discovered high levels of bird influenza viruses. The virus concentrations dissipate quickly, although the air is far from the barns.
This may be the reason why the chicken is getting sick more slowly: they got a lower dose of the virus from very low levels in the air. The fact that the first chicken to die was near the opening holes is another idea.
“I think they are making a convincing case based on the knowledge they had on farms,” said Dr. Monti Torimoril, a professor and head of veterinary medicine at the University of Minnesota, who did not participate in the new study.
Torimoril Air samples were made About poultry poultry during the last large outbreak of bird flu in the United States in 2015. I found high levels of infectious viruses that blow from the great exhaust lovers in the role of poultry.
She is not just a matter of how long the virus blows into the air, but also where it lands. These may end the infectious aerosol columns with clothes, equipment and compounds that can also carry the virus from one place to another.
Methods with layers for protection
Torimoril said that the air deployment should be the farmer that farms think when they think about ways to protect livestock and shots.
“I think the air transmission is by air should be on the table,” she said.
But it is difficult to offer because people may hear a “mobile spread” and feel unable to stop the virus.
“Often, people say,” Oh, he is in the wind. I can’t do anything about it. Then they stop doing the basic biological security that it is extremely important to have to do. “
But she says they forget lessons from Covid-19 on how to stop the spread of the virus requires layers of protection. Current precautions such as restricting entry to farms and wearing personal protection equipment should remain in place, but air filtering in the barns can also help protect animals and agricultural workers from bird flu as well.
Dr. Michael Ostohm, who directs the Center for Infectious Research and Policy at the University of Minnesota, also believes that the spread of WindBorne plays a role in the transmission of H5N1 now.
He said: “I think there is more wind -based H5N1, which now occurs in society because of a number of infected water birds.”
He says that water birds such as ducks and geese in the lakes, and the winds that blow over that water may carry the virus to nearby farms.
“We are in an unprecedented area at the present time,” said Austhnolm. “Everything all over the country.”
Osterholm believes that air deployed or wind may explain some infections that cannot be determined by a source of the virus – such as connecting to a sick animal. The last case of the three veterinarians who have experienced positive antibodies against the H5N1 virus at a conference. Two of the three did not have a known exposure to sick animals.
“I think it is a very low risk for humans to have such a virus, but I think it is happening,” he said.
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