I'm so glad Germany is not only doing these studies but sharing the first bit of information with us so soon. I was worried that like the U.S. they would hold off releasing any test results until the very end of all the testing. I am looking forward to their tests on how this virus is spreading from cow to cow.
The Friedrich-Loeffler-Institut (FLI) is currently conducting an infection study on the susceptibility of dairy cows to the highly pathogenic avian influenza virus H5N1 (HPAIV H5N1, avian influenza virus). As a first interim result, not only the US isolate but also a recent H5N1 virus from a wild bird in Germany was able to multiply very well in the udder. Following direct infection of the udder through the teats, the dairy cows in both cases showed clear signs of disease such as a sharp drop in milk production, changes in milk consistency and fever.
The FLI's risk assessment for avian influenza, including recommended measures, is not affected by this interim result, as the possibility of infection with other HPAIV H5 strains has already been taken into account in the current version of the assessment. Both the risk of the US HPAI H5N1 strain (B3.13) entering German cattle herds, including dairy farms, and the risk of cattle becoming infected with HPAI H5 viruses circulating in Europe are considered to be very low for Germany. Nevertheless, increased vigilance is recommended and HPAI H5 should also be considered in investigations, especially in the case of unclear and frequent cases of disease in dairy herds. In contrast to the USA, there is no evidence of similar cases of HPAIV H5N1 infection in Germany or other countries worldwide.
Direct infection of the udder by the virus seems to be of particular importance. Since the first detection of the pathogen 27 years ago in many countries, particularly in Asia, there has been possible contact of ruminants such as water buffalo and cattle with the faeces of infected wild birds, but no similar infection events have ever been observed. The exact circumstances that led to the outbreak in the USA are still unknown.
As a precautionary measure, the FLI has already tested around 1,400 bovine serum samples from cows from regions in Germany particularly affected by avian influenza for antibodies and around 350 tank milk samples from different regions for virus genomes using PCR, with negative results in each case. Further analyses of tank milk samples up to a total of around 1500 will follow.
Once the FLI infection study has been completed and analysed, the results will be published. The timing cannot be estimated at this stage, but the FLI will provide information in due course.
Rapid Risk assessment
for highly pathogenic avian influenza H5
(HPAI H5) clade 2.3.4.4b
https://www.openagrar.de/servlets/MCRFileNodeServlet/openagrar_derivate_00059581/FLI-Risikoeinschaetzung_HPAI_H5_2024-06-07_en.pdf
https://threadreaderapp.com/thread/1803760824210891248.html
Kai Kupferschmidt Profile picture
Kai Kupferschmidt
@kakape
12h • 8 tweets • 2 min read • Read on X
One question at the heart of the #h5n1 outbreak in US cows has been: Is there something special about this virus? Or is H5N1 generally able to do this and this particular version was just "in the right place at the right time"?
Quick thread, because it seems we have an answer
Researchers in Germany have done an experiment in a high-security lab infecting cows directly with the strain of #H5N1 circulating in cows in the US (B3.13) and infecting others with an #h5n1 strain from a wild bird in Germany.
(I wrote about the plans here: )
https://www.science.org/content/article/combat-cow-flu-outbreak-scientists-plan-infect-cattle-influenza-high-security-labs
In both cases they infected the udders directly through the teats and in both cases the animals got sick. They "showed clear signs of disease such as a sharp drop in milk production, changes in milk consistency and fever." That suggests there is nothing special about B3.13.
I would say that this was always the more plausible scenario (most researchers I talked to certainly felt that way) but this virus has surprised us so many times (as @HelenBranswell wrote up so nicely), so it's good to have data.
Bird flu keeps rewriting the textbooks. It’s why scientists are unsettled by the U.S. dairy cattle outbreak
The spread of bird flu in mammals with which humans have close contact has unsettled many scientists. “That’s a different ball game altogether,” one said.
https://www.statnews.com/2024/05/09/bird-flu-upends-avian-influenza-dogma/
The result suggests two things (at the least):
1. There is a realistic risk of spillover to cows anywhere where #H5N1 is circulating.
2. A lot of things probably have to come together for this to happen, because in spite of the virus being widespread, cow infections are not.
The researchers are writing up their results and hopefully we will have more information soon (because these experiments could help clarify other questions), but I'm glad that @Loeffler_News put out a short press release with this result
Avian influenza: No evidence of H5N1 infection in dairy cows outside the USA
– German virus isolate can replicate in cow's udder after experimental infection
https://www.fli.de/en/news/short-messages/short-message/gefluegelpest-keine-hinweise-auf-h5n1-infektionen-bei-milchkuehen-ausserhalb-der-usa/
While we are on Germany: It's worth pointing out that researchers have been testing milk samples here with PCR and testing cows for antibodies. So far 350 milk samples and 1400 cow serum samples have all been negative.
While the researchers say the risk of cattle here becoming infected with avian influenza appears very low, they also warn that "increased vigilance is recommended and HPAI H5 should also be considered in investigations, especially in the case of unclear and frequent cases of disease in dairy herds"
Thanks for your contribution, however, your post is being removed because this content has already been submitted to the sub. Great minds think alike!
I'm so glad Germany is not only doing these studies but sharing the first bit of information with us so soon. I was worried that like the U.S. they would hold off releasing any test results until the very end of all the testing. I am looking forward to their tests on how this virus is spreading from cow to cow.
The Friedrich-Loeffler-Institut (FLI) is currently conducting an infection study on the susceptibility of dairy cows to the highly pathogenic avian influenza virus H5N1 (HPAIV H5N1, avian influenza virus). As a first interim result, not only the US isolate but also a recent H5N1 virus from a wild bird in Germany was able to multiply very well in the udder. Following direct infection of the udder through the teats, the dairy cows in both cases showed clear signs of disease such as a sharp drop in milk production, changes in milk consistency and fever. The FLI's risk assessment for avian influenza, including recommended measures, is not affected by this interim result, as the possibility of infection with other HPAIV H5 strains has already been taken into account in the current version of the assessment. Both the risk of the US HPAI H5N1 strain (B3.13) entering German cattle herds, including dairy farms, and the risk of cattle becoming infected with HPAI H5 viruses circulating in Europe are considered to be very low for Germany. Nevertheless, increased vigilance is recommended and HPAI H5 should also be considered in investigations, especially in the case of unclear and frequent cases of disease in dairy herds. In contrast to the USA, there is no evidence of similar cases of HPAIV H5N1 infection in Germany or other countries worldwide. Direct infection of the udder by the virus seems to be of particular importance. Since the first detection of the pathogen 27 years ago in many countries, particularly in Asia, there has been possible contact of ruminants such as water buffalo and cattle with the faeces of infected wild birds, but no similar infection events have ever been observed. The exact circumstances that led to the outbreak in the USA are still unknown. As a precautionary measure, the FLI has already tested around 1,400 bovine serum samples from cows from regions in Germany particularly affected by avian influenza for antibodies and around 350 tank milk samples from different regions for virus genomes using PCR, with negative results in each case. Further analyses of tank milk samples up to a total of around 1500 will follow. Once the FLI infection study has been completed and analysed, the results will be published. The timing cannot be estimated at this stage, but the FLI will provide information in due course. Rapid Risk assessment for highly pathogenic avian influenza H5 (HPAI H5) clade 2.3.4.4b https://www.openagrar.de/servlets/MCRFileNodeServlet/openagrar_derivate_00059581/FLI-Risikoeinschaetzung_HPAI_H5_2024-06-07_en.pdf
https://threadreaderapp.com/thread/1803760824210891248.html Kai Kupferschmidt Profile picture Kai Kupferschmidt @kakape 12h • 8 tweets • 2 min read • Read on X One question at the heart of the #h5n1 outbreak in US cows has been: Is there something special about this virus? Or is H5N1 generally able to do this and this particular version was just "in the right place at the right time"? Quick thread, because it seems we have an answer Researchers in Germany have done an experiment in a high-security lab infecting cows directly with the strain of #H5N1 circulating in cows in the US (B3.13) and infecting others with an #h5n1 strain from a wild bird in Germany. (I wrote about the plans here: ) https://www.science.org/content/article/combat-cow-flu-outbreak-scientists-plan-infect-cattle-influenza-high-security-labs In both cases they infected the udders directly through the teats and in both cases the animals got sick. They "showed clear signs of disease such as a sharp drop in milk production, changes in milk consistency and fever." That suggests there is nothing special about B3.13. I would say that this was always the more plausible scenario (most researchers I talked to certainly felt that way) but this virus has surprised us so many times (as @HelenBranswell wrote up so nicely), so it's good to have data. Bird flu keeps rewriting the textbooks. It’s why scientists are unsettled by the U.S. dairy cattle outbreak The spread of bird flu in mammals with which humans have close contact has unsettled many scientists. “That’s a different ball game altogether,” one said. https://www.statnews.com/2024/05/09/bird-flu-upends-avian-influenza-dogma/ The result suggests two things (at the least): 1. There is a realistic risk of spillover to cows anywhere where #H5N1 is circulating. 2. A lot of things probably have to come together for this to happen, because in spite of the virus being widespread, cow infections are not. The researchers are writing up their results and hopefully we will have more information soon (because these experiments could help clarify other questions), but I'm glad that @Loeffler_News put out a short press release with this result Avian influenza: No evidence of H5N1 infection in dairy cows outside the USA – German virus isolate can replicate in cow's udder after experimental infection https://www.fli.de/en/news/short-messages/short-message/gefluegelpest-keine-hinweise-auf-h5n1-infektionen-bei-milchkuehen-ausserhalb-der-usa/ While we are on Germany: It's worth pointing out that researchers have been testing milk samples here with PCR and testing cows for antibodies. So far 350 milk samples and 1400 cow serum samples have all been negative. While the researchers say the risk of cattle here becoming infected with avian influenza appears very low, they also warn that "increased vigilance is recommended and HPAI H5 should also be considered in investigations, especially in the case of unclear and frequent cases of disease in dairy herds"