空気と廃水が酪農場でH5N1型鳥インフルエンザを拡散する仕組み：新たな研究結果の解説
How air and wastewater spread H5N1 aliven flu on dairy farms. New findings explained. Air and wastewater. The hidden pathways of H5N1 transmission. Although the recent surge of H5N1 aven influenza outbreaks on US dairy farms has notably dwindled, scientists remain deeply engaged in unraveling how this virus continues to circulate within agricultural environments. What’s emerging from recent California case studies may raise eyebrows. The virus could be drifting through the air and lurking in wastewater. A collaborative research effort led by Emmery University along with experts from several states including California, Colorado, Michigan, and Virginia has just released a pre-publication report detailing their findings from in-depth experiments conducted on 14 dairy farms spread across two regions in California. These observations published on the Bioarchs of server offer compelling new evidence. Slwww.bioarchsive.org content/1025.07.31.66798V1 full.pdf. And here’s the part most people miss. While the summer saw a decrease in officially reported cases, the virus hasn’t vanished. H5N1 continues to pop up sporadically among dairy cows. In fact, according to today’s report from the US Department of Agricultures Aphus division, https colon/www.afis.usda/ USDA gov/ livestock poultry disease/avvian/influenza/hpia detections/hpia confirmed cases in livestock. Another infected herd in California has pushed the national total to 1,078 confirmed herds since early 2024. Notably, California alone accounts for 771 of those cases. virus in the air, especially during milking routines. Initially, experts believed that contact with contaminated milking machines and milk itself were the primary culprits behind the virus’s rapid spread. But with intense outbreaks striking places like Colorado and California, research teams began looking at additional transmission vectors. For this new investigation, researchers collected hundreds of samples from air, wastewater, and milk at multiple farms. During the air testing phase, they employed three distinct devices, including a backpack mounted PTFE filter cassette to simulate the exposure experienced by dairy workers. They sampled breath particles from individual cows and groups during milking sessions and in their living quarters. Out of 71 air samples, six tested positive for H5N1 RNA, and yes, one was from the worker exposure backpack device. The plot thickens when researchers added another round of air testing on nine more farms, some in Southern California. They discovered viral RNA in 21 of 35 samples. Even more surprising, four samples contained live infectious virus. This strongly suggests that during milking operations, the virus isn’t just present. It’s floating in the air and it’s active contaminated waste water. The stealthy spreader researchers didn’t stop at air. They turned their attention to waste water, specifically water used to sanitize equipment and animal areas, and took samples from drain systems, pumps, fields, and manure lagoons. Viral RNA appeared across the board, including lagoons frequented by migratory birds and fields where cows graze. But here’s where it gets controversial. Two samples with especially high viral loads contained infectious virus particles. This indicates that reclaimed waste water might not just be a secondary concern. It could be a significant conduit for H5N1 between cows, farm workers, and even domestic animals. Digging deeper into the virus’s behavior, the researchers expanded their scope by performing genome sequencing on a subset of the virus samples, uncovering unique amino acid changes, including some in the hemoglutin segment. Interestingly, these mutations didn’t appear to stick around. The team also noticed genetic differences between farms, which could help track how the virus moves within herds. Milk samples from individual cow udders showed frequent subclinical infections, meaning cows were infected without showing symptoms. These infections were unevenly distributed across uers, but consistently maintained the same pattern, hinting at persistent viral behavior. So, what does all this mean for prevention? Multiple transmission routes, airborne particles, contaminated equipment, infected milk, and wastewater require a multi-layered defense strategy. The researchers emphasize the urgent need for protective gear, especially eye and respiratory shields, rigorous equipment sanitation, proper treatment of waste water and milk, and thorough identification of infected cows even when they appear healthy. Now, let’s open up the conversation. Should waste water be treated with the same urgency as airborne transmission? Are current farm safety protocols enough? Or do they need a complete overhaul? Some may argue this is overblown. But what if it’s not? Share your thoughts below. Your opinion could help shape a safer future for farms and communities alike. Aven influenza, global emergency. Why vaccinating birds is crucial now. Aven influenza has now escalated into a global emergency. A stark reality that should prompt serious consideration of vaccinating birds against this devastating disease. According to a recent publication by the World Organization for Animal Health, W. The past two decades have seen over 633 million birds lost either to the virus itself or to culling efforts aimed at controlling its spread. What was once considered a seasonal or region specific concern has morphed into a year-round threat that has crossed geographical boundaries, infecting a wider array of wild bird species and an increasing number of mammals. Occasionally, humans have fallen victim as well, fueling fears about the virus’s potential to morph into a significant public health crisis. Most of us are likely aware of the general situation, though the sheer number of bird losses might come as a shock. It’s no wonder then that the WHA’s recently released State of the World’s Animal Health 2025 report emphasizes the urgent need for action that transcends traditional control methods. While containment efforts have been robust, the report underscores that more must be done here. Vaccination emerges as a promising strategy to complement existing measures, helping to reduce both the spread and the severity of infections. The report also highlights the drawbacks of traditional sanitary control measures such as mass culling, which have proven to be not only economically costly, but also socially disruptive, raising doubts about their long-term viability. The WA’s stance on vaccination is evolving. While biocurity, surveillance and movement controls remain foundational, vaccination can significantly enhance these efforts by decreasing virus circulation within and between flocks, mitigating economic losses, and lowering the risk of the virus spilling over into wildlife and human populations. Are cows carrying bird flu? What you need to know about virus transmission. Here’s a twist in the ongoing battle against aven flu. The viruses currently infecting dairy cows in the US are more closely related to bird flu than to human influenza. This revelation from a groundbreaking study at St. Jude Children’s Research Hospital challenges assumptions about how these viruses might evolve and what that means for human health. But here’s where it gets controversial. While the risk of a pandemic seems low for now, the threat of direct infection for those working closely with cattle remains a pressing concern. Let’s unpack why this matters. Since 2024, scientists have been on high alert after detecting H5N1 bird flu in dairy herds. The fear that cows could act as a bridge for the virus to mutate and jump to humans. But the latest research paints a different picture. By comparing the genetic makeup of cow viruses to those from birds and humans, researchers found striking similarities to aven strains. In fact, the viruses retained key traits that make them better suited to infect birds than mammals. This suggests the virus isn’t adapting to humans as quickly as some feared. And this is the part most people miss. Even though airborne transmission between mammals is unlikely, direct contact with infected cows can lead to human infections. So far, 41 cases have been linked to close exposure in dairy farms. To test this, scientists used a mamalon model to simulate human infection. While the virus couldn’t spread through the air, it could pass between models via direct contact. This duality, low pandemic risk, but high occupational risk, has sparked heated debate. Should we be more worried about farm workers than the general public? The study also explored whether existing flu treatments could help. Researchers tested antiviral drugs commonly used for influenza and found they were effective against cowder derived H5N1 in lab settings. However, the virus’s ability to evolve complicates things. As one of the study’s lead authors, Richard Webbby explained, “These viruses aren’t under pressure to adapt to humans, but that doesn’t mean they’re harmless. Infected models still showed severe symptoms and some humans have fallen ill. So where does this leave us? The findings offer a glimmer of hope. Current vaccines and antivirals may provide some protection, but the researchers caution that this isn’t a green light. The virus is still mutating and a new variant could change the game entirely. This raises a critical question. Are we underestimating the long-term risks of zunotic diseases? We’d love to hear your thoughts. Do you think the focus should shift to protecting farm workers, or should we prepare for a potential pandemic? Share your take in the comments below.
00:00 – How Air and Wastewater Spread H5N1 Avian Flu on Dairy Farms: New Findings Explained
06:09 – Avian Influenza Global Emergency: Why Vaccinating Birds is Crucial Now
08:19 – Are Cows Carrying Bird Flu? What You Need to Know About Virus Transmission
1. How Air and Wastewater Spread H5N1 Avian Flu on Dairy Farms: New Findings Explained
Explore the latest research on H5N1 avian influenza transmission on US dairy farms, focusing on airborne spread and contaminated wastewater. Learn how infectious virus particles are found in the air during milking and how reclaimed farm wastewater can act as a virus source. Understand the implications for farm workers’ safety and virus mitigation strategies, including PPE use, equipment disinfection, and monitoring subclinical infections.
Key topics covered:
– Airborne H5N1 virus detection in milking parlors
– Role of wastewater and manure lagoons in virus spread
– New findings from 14 California dairy farms during 2024 outbreaks
– Protective measures for farm workers
– Importance of wastewater treatment and milking equipment sanitation
– Insights into virus variants and transmission tracking on farms
This video is essential for veterinarians, dairy farmers, agricultural workers, and anyone interested in biosecurity and infectious disease control in livestock environments.
2. Avian Influenza Global Emergency: Why Vaccinating Birds is Crucial Now
Avian influenza has escalated into a global emergency, with over 633 million birds lost in 20 years. The World Organisation for Animal Health (WOAH) now advocates for bird vaccination as a key strategy to combat the crisis. This video explores how traditional measures like mass culling are proving unsustainable and why vaccination is emerging as a vital tool to protect poultry, ecosystems, and human health. Learn about the spread of the virus to new regions, its impact on wildlife and mammals, and WOAH’s urgent call for multifaceted solutions to prevent a larger public health threat.
3. Are Cows Carrying Bird Flu? What You Need to Know About Virus Transmission
New research reveals that viruses in dairy cows are more similar to bird flu than human flu. Find out how these viruses behave, their risk to humans, and what this means for outbreak prevention. Learn about recent findings from St. Jude’s and the potential implications for farm workers and public health. Stay informed about the latest in animal and human virus transmission and how scientists are tackling these threats.