Highly pathogenic avian influenza (HPAI) was identified in dairies for the first time almost one year ago. From a human health standpoint, it is a zoonosis — or a disease that can spread to humans from animals — and there have been 70 human cases of dairy farm workers contracting the virus. Most of the cases have been mild conjunctivitis, or an infection of the eye.
Keeping farm workers healthy as we continue to learn more about the HPAI virus was the focus of a recent Iowa State University “Dairy News and Views” podcast. Andrew Hennenfent, D.V.M., a public health veterinarian with the Iowa Department of Health and Human Services, addressed the complexities of the strains. “There are concerns that there could be mutations, especially if a human or cow is infected with the human strain and the cow or bird strain at the same time, there is some reassortment that goes on. We encourage people to think about getting vaccinated (for influenza) and talk to their doctor,” he said.
Hennenfent also reinforced that worker health, safety, and on-farm biosecurity go hand in hand. “The same steps that producers take protecting animals from getting diseases from other farms and other animals will also help protect their farm workers,” he noted. He discussed how when there is an issue with HPAI on a farm, the highest exposure risk is in the milking parlor. Milk coming from infected dairy cows has high concentrations of the virus. He added that the highest risk for humans is getting the virus directly in the eyes, nose, and mouth.
Similar steps of prevention and tactics used to prevent the spread of human seasonal influenza hold true for the spread of HPAI to humans. These steps include providing handwashing stations and frequent handwashing practices. Ideally, farm workers should be outfitted with personal protective equipment (PPE) to prevent contracting the virus, especially in the milking parlor. These measures of protection through PPE include a face mask, eye protection, gloves, waterproof apron, coveralls, and boots.
In addition to wearing PPE while working, an important step is putting on and taking off protection safely after each use. The use of PPE not only has the benefit of protecting humans from animal viruses, but there are added benefits of protecting animals from humans and preventing virus transmissions from farm to farm.
A wide range of animals can be affected by HPAI, and through the last year of addressing this virus in dairies, it has also been discovered to be deadly in cats. The most common transmission is the practice of feeding unpasteurized milk to farm cats. To keep cats healthy, the public health experts on the podcast recommended feeding only commercially processed cat food.
The Iowa State University Extension team recommended visiting the Center for Disease Control (CDC) websites for additional information on preventing the cow-to-human spread of HPAI, in English: Information for Farm Workers and in Spanish: Spanish version of Information for Farm Workers.
