Human infections with novel influenza A viruses (such as H5N1 Bird Flu) can happen when enough virus gets into a person´s eyes, nose, or mouth, or is inhaled. This can happen when virus is in the air (in droplets, small aerosol particles, or possibly dust) and deposits on the mucus membranes of the eyes or a person breathes it in, or possibly when a person touches something contaminated by viruses and then touches their mouth, eyes, or nose.

Employers should take steps to reduce workers´ risk of infection with novel influenza A viruses from sick animals or contaminated environments. Workers may be at risk when working with animals confirmed or potentially infected with novel influenza A viruses or working with materials, including raw milk, that are confirmed or potentially contaminated with novel influenza A viruses. Examples of related workers include:

Poultry and dairy and other livestock farmers and workers
Backyard bird flock owners
Veterinarians and veterinary staff
Animal health responders
Public health responders
Dairy laboratory workers
Food processing workers handling raw milk and other confirmed or potentially contaminated materials
Slaughterhouse workers performing certain tasks on lactating dairy cattle including:
Unloading or handling live lactating dairy cattle for slaughter, including working in holding pens and tasks involved with ante-mortem inspection
Post-mortem processes including the post-mortem inspection, handling, and transporting of viscera
Removing and transporting udders from dairy cattle for further processing or rendering
To protect workers who might be exposed, employers should update or develop a workplace health and safety plan. Employers are encouraged to use a health and safety committee that includes representatives from both management and workers to develop the plan. Helpful guidance and consultation on developing a workplace health and safety plan is available from the Occupational Safety and Health Administration (OSHA) and through your local agriculture extension office. Employers should conduct a site-specific hazard assessment to identify potential exposures based on job tasks and locations and use the hierarchy of controls to identify controls to reduce or eliminate hazards including exposure to novel influenza A viruses. The Hazard Assessment Worksheet for Dairy Facilities can help identify dairy workplace hazards and prioritize controls including PPE needed for protection. Protecting Poultry Workers from Avian Influenza (Bird Flu) can help identify poultry workplace hazards and prioritize controls.

Employers should ensure workers are protected from being exposed to the virus if workers have direct or close physical contact with:

Any animals that are confirmed or potentially infected, including birds, dairy cows, and other livestock
Feces, urine, or litter from these animals
Raw (unpasteurized) milk from these animals
Any animals that have died, including birds and livestock
Viscera or udders from lactating dairy cattle
Surfaces and water (for example, ponds, waterers, buckets, pans, troughs) on farms with potentially infected animals that might be contaminated with animal waste or waste milk
CDC provides separate recommendations to prevent the spread of flu between pigs and people.

The hierarchy of controls identifies a preferred order of actions to best control hazardous workplace exposures. Engineering controls are more effective than administrative controls or PPE because they control exposures without requiring significant and ongoing efforts by workers and their supervisors.

Engineering Controls
Engineering controls are methods to reduce or remove the hazard at the source or place a barrier between the worker and the hazard.

Proper ventilation in dairy and poultry barns depends on factors such as the size of the barn, the number of animals, and local climate, among other factors. Poor ventilation can lead to the buildup of harmful gases, excessive heat and humidity, and the accumulation of airborne pathogens (bacteria and viruses). Circulating fresh air helps dilute and disperse potential pathogens and can help control the temperature and humidity.

Employers should implement the following engineering controls to reduce the spread of novel influenza A viruses:

Use a ventilation system that provides a constant supply of fresh air
Strategically place fans and vents to generate a clean-to-less-clean flow path of fresh air through the space while removing dirty air
Use airflow exhaust and makeup air supply strategies that do not discharge high velocity airflow upon building occupants
Regularly clean and maintain ventilation systems to minimize the accumulation of dust, feathers, manure particles, and other debris that can obstruct airflow and provide a breeding ground for pathogens
Administrative Controls
Administrative controls are policies and work practices that reduce workers´ exposure to hazards. Employers should implement the following policies and work practices:

Watch for sick or dead animals on your farm or workplace, and monitor animals for changes in feed consumption or production metrics
Test animals for novel influenza A virus if indicated (if relevant, consider joining the USDA HPAI Dairy Herd Status Program or contacting your State Animal Health Official about testing available within your state)
Develop plans to monitor workers for illness
Have monitoring plans ready to use when needed
Develop a process to communicate with your workers daily to determine if they are sick or have symptoms, like conjunctivitis, mild flu-like upper respiratory symptoms, or other symptoms consistent with novel influenza A virus infection
Designate management staff to maintain records for absenteeism, symptomatic workers, and testing, and review the records daily
Ask employees to monitor themselves for symptoms of illness every day while they are working with animals confirmed or potentially infected with novel influenza A viruses and during the 10 days after the last day of exposure. If they become sick while working or during those 10 days, have them isolate themselves from others and tell their supervisor and help them contact the state/local health department, and give them instructions for seeking medical evaluation and treatment. Printable instructions are available: What to do if you feel sick.
Work with the state or local health department to provide influenza testing and treatment of sick workers
Provide employees with paid time off and develop flexible leave policies to support workers to stay home if sick
Train workers on relevant equipment, procedures, and hazards (for example, risk of exposure to novel influenza A virus through contact with animals, animal secretions, or contaminated objects); infection control practices; heat illness prevention; recognizing signs and symptoms of novel influenza A virus infection in themselves and others; any new procedures in the workplace; and PPE
Provide safe storage locations for workers´ food and personal items, including clothing worn off-site, and prohibit storage of food and personal items in potentially contaminated areas, including where PPE is put on and removed
Provide workers access to hand washing stations with soap and clean water
Provide alcohol-based hand sanitizer containing at least 60% alcohol if soap and water are not immediately available
Place hand washing stations and alcohol-based hand sanitizer in multiple locations to encourage hand hygiene, especially in areas where workers frequently have contact with animals
If possible, choose hand washing stations, hand sanitizer stations, and trash receptacles that are touch-free
Consider other workplace programs to promote personal hygiene like building additional short breaks into staff schedules
Remind workers to wash their hands for 20 seconds before eating, drinking, touching their phones, smoking, vaping, chewing gum, or dipping tobacco
Personal Protective Equipment
Engineering and administrative controls are likely not sufficient for reducing exposures to confirmed or potentially infected animals and their secretions. Therefore, PPE is needed in some cases to reduce the exposures, especially for workers in direct contact with animals or their secretions. Employers should provide appropriate PPE at no cost and training on its use, and putting on and removing PPE should occur during work hours. PPE should be used in accordance with OSHA regulations found at 29 CFR part 1910, Subpart I (Personal Protective Equipment). Workers should be trained on, and demonstrate an understanding of:

When to use PPE
The limitations of PPE
What PPE is necessary
How to maintain PPE
How to properly put on, use, remove, and dispose of PPE according to local and state regulations and authorities
Persons who need protection from novel influenza A viruses should wear appropriate PPE in addition to the PPE required for normal duties and other hazards (for example, waterproof apron, hearing protection). Appropriate PPE depends on a site-specific hazard assessment and the hazards identified.

Recommended PPE to protect against novel influenza A viruses:
NIOSH Approved? particulate respirator
Fluid-resistant coveralls or fluid-resistant sleeved apron
Optional waterproof apron over the top of coveralls
Safety goggles
Optional face shield over the top of goggles
Boot covers or boots
Head cover or hair cover
Disposable gloves with optional outer work gloves