sharon sanders
Editor-in-Chief & President
Updates on Highly Pathogenic Avian Influenza (HPAI)
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Highly Pathogenic Avian Influenza (HPAI) is a disease that is highly contagious and often deadly in poultry, caused by highly pathogenic avian influenza A (H5) and A (H7) viruses; it is also known as bird or avian flu. HPAI viruses can be transmitted by wild birds to domestic poultry and other bird and animal species. Although bird flu viruses do not normally infect humans, sporadic human infections have occurred. It is important to note that “highly pathogenic” refers to severe impact in birds, not necessarily in humans. Ongoing Work to Ensure Continued Effectiveness of the Federal-State Milk Safety System
What's New | Previous Updates
Background | U.S. Agency Response | Testing Results | Additional Resources
What's New
September 26, 2024
The FDA is providing an update about ongoing research efforts it is undertaking to help ensure the safety of dairy products during the outbreak of Highly Pathogenic Avian Influenza A (H5N1) virus in dairy cattle and to work towards reducing the threat of H5N1 to human and animal health.
Since outlining the FDA’s research objectives in summer 2024 through the FDA’s research agenda, the FDA has continued collaborating with our federal and academic partners to conduct the imperative work to understand the effectiveness of inactivation methods and further assure the safety of retail dairy products. Through FDA H5N1 funding and in cooperation with Cornell University, the University of Wisconsin-Madison, National Institutes of Health Rocky Mountain Laboratories (NIH-RML) and Centers of Excellence for Influenza Research and Response (NIH-CEIRR) partners, the University of Georgia and St. Jude Children’s Research Hospital, the FDA is advancing the following applied research:
Thermal Inactivation Kinetic Studies: In collaboration with Cornell University, NIH-RML, and the University of Georgia, the FDA will determine the effects of various time and temperature combinations outside of standard pasteurization parameters and temperature combinations on H5N1 viability in fluid milk that will allow objective risk assessments of various dairy product manufacturing processes.
Viral Inactivation Studies: In collaboration with Cornell University, the FDA will assess H5N1 inactivation under different aged raw milk cheese manufacturing processes.
H5N1 Viability Testing: The FDA has partnered with Cornell University, the University of Georgia, and St. Jude Children’s Research Hospital to provide H5N1 virus viability testing as needed.
One Health Interventions: In collaboration with Cornell University, the FDA will investigate practical disposal measures for raw milk waste. In collaboration with the University of Wisconsin-Madison, the FDA will explore the development of genome-edited chickens to reduce susceptibility or provide resistance to H5N1 and other avian viruses.
The FDA, alongside its partners, expects to share further updates on these research efforts in the coming months. We continue to affirm the safety of the commercial milk supply by ongoing sampling and testing of retail dairy products. The agency remains committed to taking a stepwise approach to its scientific analysis of the safety of the commercial milk supply and interventions that reduce human and animal health risks.
Previous Updates
September 18, 2024
August 22, 2024
August 13, 2024
June 28, 2024
June 25, 2024
June 12, 2024
June 6, 2024
May 10, 2024
May 1, 2024
April 26, 2024
April 25, 2024
Background
The U.S. Department of Agriculture (USDA), the U.S. Food and Drug Administration (FDA), and the Centers for Disease Control and Prevention (CDC), along with state partners, continue to investigate an outbreak of highly pathogenic avian influenza (HPAI) virus impacting dairy cows in multiple states. Infection with the virus is causing decreased lactation, low appetite, and other symptoms in affected cattle.
The FDA and USDA have indicated that based on the information currently available, our commercial milk supply is safe because of these two reasons:
1) the pasteurization process and
2) the diversion or destruction of milk from sick cows.
The pasteurization process has served public health well for more than 100 years. Pasteurization is a process that kills harmful bacteria and viruses by heating milk to a specific temperature for a set period of time to make milk safer. Even if virus is detected in raw milk, pasteurization is generally expected to eliminate pathogens to a level that does not pose a risk to consumer health. However, pasteurization is different than complete sterilization; sterilization extends shelf life but is not required to ensure milk safety. While milk is pasteurized, not sterilized, this process has helped ensure the health of the American public for more than 100 years by inactivating infectious agents.
Nearly all (99%) of the commercial milk supply that is produced on dairy farms in the U.S. comes from farms that participate in the Grade “A” milk program and follow the Pasteurized Milk Ordinance (PMO), which includes controls that help ensure the safety of dairy products. Pasteurization and diversion or destruction of milk from sick cows are two important measures that are part of the federal-state milk safety system.
U.S Agency Response
Second Retail Sample Survey Results (August 13, 2024)
On Aug. 13, 2024, the FDA announced the results from the agency’s second survey of retail dairy products. Samples were processed and analyzed by a USDA-Agricultural Research Services (ARS) laboratory from June 18 – July 31, 2024. All 167 samples were found to be negative for viable H5N1 virus. The FDA’s second sampling survey tested dairy products collected at retail locations, including aged raw milk cheese, pasteurized fluid milk and products made from pasteurized milk, such as pasteurized cheeses, cream cheese, butter, and ice cream.
The samples, collected by a third party, were aseptically repackaged to remove identifying manufacturing marks and then sent to USDA-ARS for extraction and analysis. USDA reported the results to the FDA. No viable virus was detected in the samples. These results strengthen previous assessments that commercial pasteurization inactivates the H5N1 virus. The study is published in the Journal of Food Protection: Inactivation of Highly Pathogenic Avian Influenza Virus with High-temperature Short Time Continuous Flow Pasteurization and Virus Detection in Bulk Milk TanksExternal Link Disclaimer.
The tables below provide additional details on the samples and test results for our second survey of retail dairy products.
Table 1: Breakdown of Retail Sample Results by State Where Fluid Milk Was Processed
Table 2: Breakdown of Retail Sample Results by Product Type
First Retail Sample Survey Results (May 10, 2024)
Additional Resources
https://www.fda.gov/food/alerts-adv...pdates-highly-pathogenic-avian-influenza-hpai
Subscribe to Email Updates
Highly Pathogenic Avian Influenza (HPAI) is a disease that is highly contagious and often deadly in poultry, caused by highly pathogenic avian influenza A (H5) and A (H7) viruses; it is also known as bird or avian flu. HPAI viruses can be transmitted by wild birds to domestic poultry and other bird and animal species. Although bird flu viruses do not normally infect humans, sporadic human infections have occurred. It is important to note that “highly pathogenic” refers to severe impact in birds, not necessarily in humans. Ongoing Work to Ensure Continued Effectiveness of the Federal-State Milk Safety System
What's New | Previous Updates
Background | U.S. Agency Response | Testing Results | Additional Resources
What's New
September 26, 2024
The FDA is providing an update about ongoing research efforts it is undertaking to help ensure the safety of dairy products during the outbreak of Highly Pathogenic Avian Influenza A (H5N1) virus in dairy cattle and to work towards reducing the threat of H5N1 to human and animal health.
Since outlining the FDA’s research objectives in summer 2024 through the FDA’s research agenda, the FDA has continued collaborating with our federal and academic partners to conduct the imperative work to understand the effectiveness of inactivation methods and further assure the safety of retail dairy products. Through FDA H5N1 funding and in cooperation with Cornell University, the University of Wisconsin-Madison, National Institutes of Health Rocky Mountain Laboratories (NIH-RML) and Centers of Excellence for Influenza Research and Response (NIH-CEIRR) partners, the University of Georgia and St. Jude Children’s Research Hospital, the FDA is advancing the following applied research:
Thermal Inactivation Kinetic Studies: In collaboration with Cornell University, NIH-RML, and the University of Georgia, the FDA will determine the effects of various time and temperature combinations outside of standard pasteurization parameters and temperature combinations on H5N1 viability in fluid milk that will allow objective risk assessments of various dairy product manufacturing processes.
Viral Inactivation Studies: In collaboration with Cornell University, the FDA will assess H5N1 inactivation under different aged raw milk cheese manufacturing processes.
H5N1 Viability Testing: The FDA has partnered with Cornell University, the University of Georgia, and St. Jude Children’s Research Hospital to provide H5N1 virus viability testing as needed.
One Health Interventions: In collaboration with Cornell University, the FDA will investigate practical disposal measures for raw milk waste. In collaboration with the University of Wisconsin-Madison, the FDA will explore the development of genome-edited chickens to reduce susceptibility or provide resistance to H5N1 and other avian viruses.
The FDA, alongside its partners, expects to share further updates on these research efforts in the coming months. We continue to affirm the safety of the commercial milk supply by ongoing sampling and testing of retail dairy products. The agency remains committed to taking a stepwise approach to its scientific analysis of the safety of the commercial milk supply and interventions that reduce human and animal health risks.
Previous Updates
September 18, 2024
August 22, 2024
August 13, 2024
June 28, 2024
June 25, 2024
June 12, 2024
June 6, 2024
May 10, 2024
May 1, 2024
April 26, 2024
April 25, 2024
Background
The U.S. Department of Agriculture (USDA), the U.S. Food and Drug Administration (FDA), and the Centers for Disease Control and Prevention (CDC), along with state partners, continue to investigate an outbreak of highly pathogenic avian influenza (HPAI) virus impacting dairy cows in multiple states. Infection with the virus is causing decreased lactation, low appetite, and other symptoms in affected cattle.
The FDA and USDA have indicated that based on the information currently available, our commercial milk supply is safe because of these two reasons:
1) the pasteurization process and
2) the diversion or destruction of milk from sick cows.
The pasteurization process has served public health well for more than 100 years. Pasteurization is a process that kills harmful bacteria and viruses by heating milk to a specific temperature for a set period of time to make milk safer. Even if virus is detected in raw milk, pasteurization is generally expected to eliminate pathogens to a level that does not pose a risk to consumer health. However, pasteurization is different than complete sterilization; sterilization extends shelf life but is not required to ensure milk safety. While milk is pasteurized, not sterilized, this process has helped ensure the health of the American public for more than 100 years by inactivating infectious agents.
Nearly all (99%) of the commercial milk supply that is produced on dairy farms in the U.S. comes from farms that participate in the Grade “A” milk program and follow the Pasteurized Milk Ordinance (PMO), which includes controls that help ensure the safety of dairy products. Pasteurization and diversion or destruction of milk from sick cows are two important measures that are part of the federal-state milk safety system.
U.S Agency Response
Second Retail Sample Survey Results (August 13, 2024)
On Aug. 13, 2024, the FDA announced the results from the agency’s second survey of retail dairy products. Samples were processed and analyzed by a USDA-Agricultural Research Services (ARS) laboratory from June 18 – July 31, 2024. All 167 samples were found to be negative for viable H5N1 virus. The FDA’s second sampling survey tested dairy products collected at retail locations, including aged raw milk cheese, pasteurized fluid milk and products made from pasteurized milk, such as pasteurized cheeses, cream cheese, butter, and ice cream.
The samples, collected by a third party, were aseptically repackaged to remove identifying manufacturing marks and then sent to USDA-ARS for extraction and analysis. USDA reported the results to the FDA. No viable virus was detected in the samples. These results strengthen previous assessments that commercial pasteurization inactivates the H5N1 virus. The study is published in the Journal of Food Protection: Inactivation of Highly Pathogenic Avian Influenza Virus with High-temperature Short Time Continuous Flow Pasteurization and Virus Detection in Bulk Milk TanksExternal Link Disclaimer.
The tables below provide additional details on the samples and test results for our second survey of retail dairy products.
Table 1: Breakdown of Retail Sample Results by State Where Fluid Milk Was Processed
| AL | No | 3 | 3 | 0 | Not Performed (Negative qRT-PCR) |
| AZ | No | 1 | 1 | 0 | Not Performed (Negative qRT-PCR) |
| CA | No | 6 | 6 | 0 | Not Performed (Negative qRT-PCR) |
| CO | No | 3 | 2 | 1 | 0 |
| CT | No | 1 | 1 | 0 | Not Performed (Negative qRT-PCR) |
| DE | No | 3 | 3 | 0 | Not Performed (Negative qRT-PCR) |
| ID | No | 28 | 15 | 13 | 0 |
| IL | No | 3 | 3 | 0 | Not Performed (Negative qRT-PCR) |
| KY | No | 3 | 2 | 1 | 0 |
| LA | No | 3 | 3 | 0 | Not Performed (Negative qRT-PCR) |
| MD | No | 3 | 3 | 0 | Not Performed (Negative qRT-PCR) |
| ME | No | 1 | 1 | 0 | Not Performed (Negative qRT-PCR) |
| MI | No | 13 | 12 | 1 | 0 |
| MN | No | 6 | 6 | 0 | Not Performed (Negative qRT-PCR) |
| MS | No | 3 | 3 | 0 | Not Performed (Negative qRT-PCR) |
| MT | No | 3 | 3 | 0 | Not Performed (Negative qRT-PCR) |
| NC | No | 5 | 5 | 0 | Not Performed (Negative qRT-PCR) |
| ND | No | 1 | 1 | 0 | Not Performed (Negative qRT-PCR) |
| NE | No | 1 | 1 | 0 | Not Performed (Negative qRT-PCR) |
| NH | No | 3 | 3 | 0 | Not Performed (Negative qRT-PCR) |
| NJ | No | 1 | 1 | 0 | Not Performed (Negative qRT-PCR) |
| NM | No | 5 | 5 | 0 | Not Performed (Negative qRT-PCR) |
| OH | No | 14 | 13 | 1 | 0 |
| PA | No | 3 | 3 | 0 | Not Performed (Negative qRT-PCR) |
| RI | No | 4 | 4 | 0 | Not Performed (Negative qRT-PCR) |
| SD | No | 6 | 5 | 1 | 0 |
| TN | No | 3 | 3 | 0 | Not Performed (Negative qRT-PCR) |
| TX | No | 24 | 13 | 11 | 0 |
| VA | No | 1 | 1 | 0 | Not Performed (Negative qRT-PCR) |
| VT | No | 3 | 3 | 0 | Not Performed (Negative qRT-PCR) |
| WI | No | 10 | 10 | 0 | Not Performed (Negative qRT-PCR) |
| Skim Milk | 7 | No | 7 | 0 | 0% | N/A |
| 1% Milk | 11 | No | 9 | 2 | 18.2% | 0/11 |
| 2% Milk | 23 | No | 22 | 1 | 4.3% | 0/23 |
| Whole Milk | 38 | No | 33 | 5 | 13.2 | 0/38 |
| Heavy Cream | 1 | No | 1 | 0 | 0% | N/A |
| Cheddar Cheese | 14 | No | 12 | 2 | 14.3% | 0/14 |
| Mozzarella Cheese | 12 | No | 6 | 6 | 50.0% | 0/12 |
| Processed Cheese | 6 | No | 5 | 1 | 16.7% | 0/6 |
| Cream Cheese | 3 | No | 3 | 0 | 0% | N/A |
| Butter | 7 | No | 4 | 3 | 42.9% | 0/7 |
| Ice Cream | 22 | No | 13 | 9 | 40.9% | 0/22 |
| Aged Raw Cheese | 23 | No | 23 | 0 | 0% | N/A |
| Total | 167 | None | 138 | 29 | 17.4% | 0/167 |
Additional Resources
- Questions and Answers Regarding the Safety of Eggs During Highly Pathogenic Avian Influenza Outbreaks
- Questions and Answers Regarding Milk Safety During Highly Pathogenic Avian Influenza (HPAI) Outbreaks
- Influenza Diagnostic Tests
https://www.fda.gov/food/alerts-adv...pdates-highly-pathogenic-avian-influenza-hpai