Personal Protective Equipment Use by Dairy Farmworkers Exposed to Cows Infected with Highly Pathogenic Avian Influenza A(H5N1) Viruses — Colorado, 2024
Kristen E. Marshall, Cara C. Drehoff, Nisha B. Alden, Sergi Bellmunt-Montoya, Ginger Stringer, Allison Kohnen, Alexandra M. Mellis, Sascha Ellington, Jordan Singleton, Carrie Reed, Rachel Herlihy, Colorado Field Team, Colorado Field Team, Rachel O. Alade, Marlee Barton, Cindy Camarillo, Lauren Duval, Rebecca Hermann, Frankie Lupercio, Leovi Madera, Pamela Pagano, Jeannette Rodriguez
Abstract
The risk for transmission of highly pathogenic avian influenza A(H5N1) virus from dairy cows to humans is currently low; however, personal protective equipment (PPE) use during work activities on dairy farms has not been well described.PPE use can protect farmworkers when they are working with highly pathogenic avian influenza A(H5N1)-infected cows.The Colorado Department of Public Health and Environment (CDPHE) and the Colorado Department of Agriculture (CDA) offered PPE to all Colorado farms before or during an A(H5N1) outbreak in cows in 2024.CDPHE surveyed 83 dairy workers from three farms with a confirmed bovine A(H5N1) outbreak.Frequently reported farm worker activities included milking cows or working in the milking parlor (51%), cleaning cow manure (49%), and transporting cows (46%).Frequently reported PPE items available to workers before A(H5N1) outbreaks included gloves (88%), eye protection (e.g., safety glasses or goggles) (76%), rubber boots or boot covers (71%), and head covers (69%).N95 respirator use was low among workers who were exposed to ill cows after detection of A(H5N1) virus (26%).PPE use while working with ill cows increased a mean of 28% after detection of A(H5N1) virus on surveyed farms; use of eye protection while milking cows increased the most (40%).Public health PPE distribution, education, and collaboration with CDA might have increased PPE use on dairy farms with A(H5N1) virus-infected cows and mitigated risk for farmworkers acquiring A(H5N1) virus. Investigation and Results BackgroundOn April 25, 2024, Colorado detected highly pathogenic avian influenza (HPAI) A(H5N1) virus in cows on a dairy farm.During April-August 2024, an additional 63 dairy farms with A(H5N1) virus-positive cows were identified* in Colorado.Although transmission risk for A(H5N1) viruses from animals to humans is low, transmission has occurred in the United States, including to a dairy worker in Colorado in 2024 and to poultry workers in 2022 and 2024 (1-5).Whereas A(H5N1) virus-infected poultry typically experience rapid and high mortality, cows tend to recover (<2% herd