Interim Guidance for Employers to Reduce the Risk of Novel Influenza A for People Working with or Exposed to Animals | Bird Flu | CDC

Oct 15, 2024

This updated interim guidance identifies select occupational groups that may be at increased risk of exposure to novel influenza A viruses associated with severe disease in humans and clarifies previous recommendations. Specific recommendations for these groups may be updated as CDC learns more during this evolving situation.

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:

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:

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 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:

Administrative controls are policies and work practices that reduce workers' exposure to hazards. Employers should implement the following policies and work practices:

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:

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.

When selecting and purchasing PPE, it is important to select items that provide the level of protection needed. This includes PPE that prevents novel influenza A viruses from coming in direct contact with the eyes, nose, or mouth, or being inhaled. The PPE should also protect the hair, skin, and clothing from contact with viruses that could later be transferred to the eyes, nose, or mouth and cause infection. The following information will help you select PPE that provides protection against novel influenza A viruses. You should consult the manufacturer or supplier to understand what specifications PPE meet. Search NIOSH PPE-Info for more information on these standards.

Respiratory protection: NIOSH Approved® particulate respirator

Any NIOSH Approved® particulate respirator is recommended, for example, an N95®or greater filtering facepiece respirator, elastomeric half mask respirator with a minimum of N95 filters, or powered air-purifying respirator with HE®, PAPR100-N®, or PAPR100-P® filters.

Respirator use should be in the context of a comprehensive written respiratory protection program administered by a trained program administrator in accordance with the OSHA Respiratory Protection standard (29 CFR 1910.134) and other applicable requirements. Before using a respirator, staff must be medically cleared, fit tested, and trained on proper use of respirators, and cleaning of reusable respirators or disposal of disposable respirators as applicable. Detailed information on respiratory protection programs, including fit testing procedures, and appropriate respirator selection (for example, particulate vs. combination particulate/gas or vapor cartridge) can be accessed at OSHA's Respiratory Protection eTool. Combination cartridges may be needed when additional gas or vapor hazards such as cleaning chemicals or ammonia from waste products are present.

Workers should be trained on, and demonstrate an understanding of the following respiratory protection topics:

For information on NIOSH Approved® respirators see The Respiratory Protection Information Trusted Source.

For persons not trained or fit tested in respirator use who work with poultry and livestock, including youth workers, it is important to remember that respirators are designed primarily to be used in workplaces by adults who are part of their employer's respiratory protection program. The risks and benefits of using respirators without proper training and fit testing are uncertain. For a respirator to be most effective, it must form a seal on the face to keep particles from leaking around the edges. A tight seal should be achieved following the manufacturer's instructions when not fit-tested. Additionally, most respirators will be too big to form a proper seal for youth workers' faces, and some will be too big for people with smaller faces. Individuals who cannot wear a respirator that properly seals to the face should not work near animals confirmed or potentially infected with novel influenza A viruses or work with materials, including raw milk, that are confirmed or potentially contaminated with novel influenza A viruses.

Outer garments: Fluid-resistant coveralls or fluid-resistant sleeved apron, waterproof apron

Disposable or washable fluid-resistant coveralls are recommended, and depending on tasks, an optional disposable or reusable waterproof apron can be used over the top of coveralls. Fluid-resistant coveralls protect the underlying clothing and skin from contamination with novel influenza A viruses. Waterproof aprons protect the coveralls and allow for easy removal of gross contamination during PPE removal.

In limited settings, where the source of contamination is only from one side, a fluid-resistant coverall might be substituted with a fluid-resistant sleeved apron. This modification should be limited to milking parlors where contamination from cows can only reach the worker from one side, excluding milking parlors where cows line up on two sides that are relatively close together and splashes could come from behind. It is important to train workers that this modification only provides partial body protection and makes them more susceptible to transferring the virus from unprotected clothing through direct or indirect contact with their eyes, nose, or mouth, causing infection.

Preferably, fluid-resistant coveralls and sleeved aprons should be made of material that passes:

Eye protection: Safety goggles, face shield

Properly fitted unvented or indirectly vented safety goggles are recommended. Preferably, safety goggles should conform to ANSI Z87.1 that is marked at least Z87 D3 that indicates protection from droplets and splashes. If safety goggles conforming to this standard are not available, goggles conforming to any ANSI Z87.1 standard are acceptable, but may not provide full droplet and splash protection.

If there is a high risk of a large amount of liquid splashing onto a filtering facepiece respirator (for example, splashing raw milk or exploding eggs), consider the use of a face shield over goggles and respirator to protect the eyes and respirator. When selecting a face shield, make sure it does not change the way the goggles or respirator fit.

Try to prevent fogging of goggles and face shields. A manufacturer's anti-fog coating may help maintain clear vision. Employers and workers should be aware that under certain conditions, some PPE can alter or decrease your visual acuity and peripheral vision. Under these conditions, workers should work in pairs if possible and pay closer attention to their surroundings for hazards such as animal movement, clothing snags, cuts or punctures, and slips, trips, and falls.

Foot protection: Boot covers or boots

Reusable boot covers or boots that can be cleaned and disinfected are recommended. Use of disposable boot covers should only be considered in areas where they will remain intact. Disposable boot covers are highly susceptible to rips and tears in many agriculture environments.

Head and hair protection: Head cover or hair cover

Disposable head cover or hair cover are recommended. If hard hats are required for impact protection, they should be able to be cleaned and disinfected after each use. When selecting a hard hat, make sure it does not change the way the goggles or respirator fit.

Hand protection: Gloves, outer work gloves

Disposable gloves with optional outer work gloves are recommended. Disposable gloves protect the hands from contamination with novel influenza A viruses. Outer work gloves (for example, gloves for cold protection, manual shoveling, handling live poultry) can be worn over the inner disposable gloves to protect the inner glove and the hands. When outer work gloves are used, they should be considered contaminated unless they are able to be cleaned and disinfected according to manufacturer's instruction and disinfectant product label.

Preferably, disposable gloves should conform to ASTM D5250 (vinyl examination gloves), ASTM D6319 (nitrile rubber examination gloves), or ASTM D6977 (chloroprene examination gloves). If thicker reusable gloves are required, rubber gloves should be waterproof and exclude linings and should be able to be cleaned and disinfected after each use. Use gloves conforming to ASTM D3578 (latex rubber examination gloves) as a last resort, as an employee may not know they have a latex allergy until a reaction occurs. If latex allergies are present, avoid latex.

*Any change to the order of putting on or removing PPE should prioritize minimizing contaminant transfer from potentially contaminated protective clothing and equipment to the person's skin or regular clothing.

Provide appropriate facilities, equipment, and supplies to properly clean reusable PPE. All reusable PPE (for example, boot covers, boots, goggles, face shield, waterproof apron, elastomeric half mask respirators, powered air purifying respirators, hard hats) should be set aside, then cleaned and disinfected after every use. Generally, it is recommended that respirators be cleaned and disinfected immediately after removing. Elastomeric components vary among manufacturers and react differently to cleaning and disinfection solutions and procedures. The respirator facepiece components such as facepiece, valves, and straps require maintenance including cleaning, disinfection, and inspection prior to reuse. OSHA only requires replacing filters "where necessary," for example, when soiled, contaminated, or clogged. To clean and disinfect reusable PPE:

Employers should launder washable PPE and other garments (for example, coveralls and clothing) onsite, when possible, following these instructions:

OSHA provides additional information on methods for preventing and reducing contamination on personnel and PPE.

Agricultural work is often carried out in hot and sometimes humid environments. Employers and workers should be aware that certain circumstances can increase the risk of heat-related illnesses and injuries, including:

For example, PPE can reduce the wearer's exposure to fresh, cooling air; limit evaporation from skin; and decrease a worker's ability to drink and rehydrate. When work must be carried out in hot and/or humid environments, it is important to educate workers about symptoms of heat-related illnesses, and consider implementing additional controls to protect workers, such as:

For more on this topic visit Protecting Workers from Heat Illness, Limiting Heat Burden While Wearing PPE, Heat Stress—Recommendations, and the NIOSH Criteria for a Recommended Standard: Occupational Exposure to Heat and Hot Environment. The OSHA-NIOSH Heat Safety Tool and AIHA Heat Stress App (Apple App Store and Google Play Store) are useful resources for planning outdoor work activities based on how hot it feels throughout the day.

N95 and NIOSH Approved are certification marks of the U.S. Department of Health and Human Services (HHS) registered in the United States and several international jurisdictions. HE, PAPR100-N, and PAPR100-P are certification marks of the U.S. Department of Health and Human Services (HHS) registered in the United States.