U. S. Department of Labor
Occupational Safety and Health Administration
Directorate of Science, Technology and Medicine
Office of Occupational Medicine
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Avian Influenza Protecting Poultry Workers at Risk
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Safety and Health Information Bulletins
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SHIB 12-13-2004
This Safety and Health Information Bulletin is not a standard or
regulation, and it creates no new legal obligations. The Bulletin is
advisory in nature, informational in content, and is intended to
assist employers in providing a safe and healthful workplace.
Pursuant to the Occupational Safety and Health Act, employers must
comply with hazard-specific safety and health standards pro-mulgated
by OSHA or by a state with an OSHA-approved state plan. In addition,
pursuant to Section 5(a)(1), the General Duty Clause of the Act,
employers must provide their employees with a workplace free from
recognized hazards likely to cause death or serious physical harm.
Employers can be cited for violating the General Duty Clause if
there is a recognized hazard and they do not take reasonable steps
to prevent or abate the hazard. However, failure to implement any
recommendations in this Safety and Health Information Bulletin is
not, in itself, a violation of the General Duty Clause. Citations
can only be based on standards, regulations, and the General Duty
Clause.
Introduction
Avian influenza is a viral disease that can cause sickness and death
among poultry. On rare occasions, avian influenza virus can be
transmitted to poultry workers or others who come in contact with
infected poultry or contact contaminated surfaces. Examples of such
workers who could be at risk include poultry growers and their
employees; service technicians of poultry processing companies;
caretakers, layer barn workers, and chick movers at egg production
facilities; and workers involved in disease control and eradication
activities, including state, federal, contract, and company
employees.
This Safety and Health Information Bulletin describes measures for
protecting poultry workers when an avian influenza outbreak occurs.
It presents basic information about avian influenza and describes
measures for minimizing exposure to the virus. Links to Internet
sites are provided for those wanting more detailed information on
avian influenza, biosecurity measures, and personal protective
equipment. This document complements avian population disease
control and eradication strategies of state governments, industry,
and the U.S. Department of Agriculture (USDA).
Avian Influenza
Avian influenza is a disease caused by infection of poultry with
type A influenza viruses. The disease occurs worldwide, and all
species of birds are thought to be susceptible to it. Strains of
avian influenza are classified as being of either low pathogenicity
(most strains) or high pathogenicity.
Low-pathogenic strains typically cause few or no signs in infected
birds. When signs are seen, they may include respiratory problems,
diarrhea, a decline in egg production, or an increase in mortality.
However, under field conditions, some low-pathogenic strains (H5 and
H7 subtypes) can mutate and become highly pathogenic, leading to the
deaths of entire flocks. Highly pathogenic avian influenza is
extremely contagious and a fatal form of the disease for poultry.
Although avian influenza A viruses rarely infect humans, since 1997,
instances of human infection have occurred; some (outside the United
States) have resulted in death. The virus is excreted in the
droppings of infected birds and in their respiratory secretions.
Transmission to humans is thought to have resulted from contact with
infected sick or dead poultry or their droppings, or contact with
contaminated litter or surfaces (e.g., egg flats). The suspected
routes of entry of the virus to humans
are the mouth, nose, eyes, and lungs. Although the human health risk
of low-pathogenic avian influenza viruses is not well established,
protective measures should be taken by persons likely to have
prolonged direct or indirect exposure to any avian influenza virus
in an enclosed setting.
Measures for Protecting Poultry Workers
Follow biosecurity practices
Poultry workers should know and follow biosecurity practices to
prevent the introduction of avian influenza and other diseases into
a poultry flock. An understanding of how infection can be spread is
important for both effective biosecurity and worker safety and
health practices. Poultry processing companies should provide a
written copy of biosecurity practices to each of their contract
growers.
A 2004 USDA fact sheet lists eight general biosecurity practices for
poultry farms. Guidance is also available in the free biosecurity
CD, Infectious Disease Risk Management: Practical Biosecurity
Resources for Commercial Poultry Producers, which is available from
the U.S. Poultry and Egg Association.
Depending on temperature and moisture conditions, avian influenza A
viruses can survive in the environment for weeks. However, they are
generally sensitive to most detergents and disinfectants and are
inactivated by heating and drying. Contact with organic material
such as dust, dirt, litter, and manure can decrease the
effectiveness of some disinfectants, and thus the possibility
persists that viruses will survive. U.S. Environmental Protection
Agency
(EPA)-registered products that have a claim of being effective
against influenza viruses should provide some measure of activity
against avian influenza A viruses.
The label of an EPA-registered disinfectant describes how to use the
product safely and effectively and includes measures that
applicators should take to protect themselves. The personal
protective equipment listed on a disinfectant label is based on the
chemical's toxicity and may not be appropriate for all exposure
conditions and handling activities. Thus, an exposure assessment
should also be done when selecting personal protective equipment for
applicators.
Know the signs indicating birds are infected with avian influenza
viruses
The signs of illness seen in domestic poultry infected with avian
influenza viruses are variable and affected by the virus strain, age
and species of infected birds, concurrent bacterial disease, and the
environment. Such signs may include --
Sudden death without any signs
Lack of coordination
Purple discoloration of the wattles, combs, and legs
Soft-shelled or misshapen eggs
Lack of energy and appetite
Diarrhea
Swelling of the head, eyelids, comb, wattles, and hocks
Nasal discharge
Decreased egg production
Coughing, sneezing
Some birds might be otherwise healthy-looking but still infected
with avian influenza virus. The severity of disease in poultry can
also vary during an outbreak. Poultry workers should be aware of
signs of disease in poultry so when necessary they can take
immediate steps to protect themselves and other workers, quarantine
the farm to prevent spread of disease, and report the disease to the
responsible animal health authorities.
Take antiviral medication and get the current season's influenza
vaccine if appropriate
In the event of an avian influenza outbreak, workers who will be
involved in disease control and eradication activities should
consult their healthcare provider about the advisability of taking
antiviral medications for influenza. The Centers for Disease Control
and Prevention (CDC) has recommended that workers receive an
influenza antiviral drug daily for the entire time they are in
direct contact with infected poultry or contaminated surfaces. In
the absence of sensitivity testing, oseltamavir is the antiviral
drug currently of choice because the likelihood that the virus will
be resistant to it is less than with amantadine or rimantadine.
The CDC recommends that workers involved in avian influenza disease
control and eradication activities should get the current season's
human influenza vaccine. Human influenza vaccine will not prevent
infection with low pathogenic or highly pathogenic avian influenza A
viruses, but this precautionary measure could reduce the possibility
of dual infection with avian and human influenza viruses. Although
dual infection is unlikely, it is plausible that such a situation
might cause new and different viral strains to be created; such new
strains might be transmissible among people and lead to more
widespread infections. Although this CDC recommendation is only for
workers involved in disease control and eradication activities,
other poultry workers should consider getting the current season's
influenza vaccine for the same reason.
Current information suggests that limited human-to-human
transmission of avian influenza A viruses has occurred but is very
uncommon. Public health authorities are monitoring outbreaks of
human illness associated with avian influenza, and to date, human
infections with avian influenza viruses identified since 1997 have
not resulted in sustained human-to-human transmission.
Additional CDC information on concerns about dual infection, the use
of antiviral medications, and vaccination of poultry workers is
available at http://www.cdc.gov/flu/avian/protectionguid.htm.
Know the signs and symptoms of human infection with avian influenza
viruses
All poultry workers should know the signs and symptoms of avian
influenza virus infection in humans so that measures can be taken
for immediate treatment. The signs and symptoms may include fever,
cough, sore throat, conjunctivitis (eye infections), and muscle
aches. Infection with avian influenza viruses can also lead to
pneumonia, acute respiratory distress, and other severe and life-
threatening complications. A worker who experiences any of these
symptoms or illnesses, or who might have been exposed to avian
influenza virus should seek medical care and tell the healthcare
provider before arrival that exposure to avian influenza virus may
have occurred.
More information concerning human infection with avian influenza
viruses is available at
http://www.cdc.gov/flu/avian/professional/han081304.htm and
http://www.who.int/csr/don/2004_01_15/en/.
Wear personal protective equipment
People, including children, working daily in poultry confinement
units are at risk of exposure to a variety of contaminants including
organic dusts, gases such as ammonia, and microorganisms (viruses,
bacteria, and fungi) that can cause illness. Thus, for many poultry
workers, wearing personal protective equipment is a routine
practice. For example, wearing a respirator can reduce exposures to
airborne organic dusts that
might pose a risk of respiratory disease and decreased breathing
capacity. These exposures in the poultry industry can lead to
chronic lung disease and premature death. The National Institute for
Occupational Safety and Health (NIOSH) recommends that children
should not do any work that requires wearing a respirator.
Respirators are designed to fit adults and the likelihood that they
will fit and protect children is doubtful. (See NIOSH
Recommendations to the U.S. Department of Labor for Changes to
Hazardous Orders. This document and others concerning young workers
can be found at http://www.cdc.gov/niosh/topics/youth.)
Most cases of avian influenza virus infection in humans are thought
to have resulted from contact with infected poultry or contacting
contaminated surfaces followed by self-inoculation of the virus into
the eyes, nose or mouth. Other means of transmission are possible,
such as airborne material containing the virus entering a person's
mouth, nose, or eyes, or being inhaled into the lungs.
The CDC and the Occupational Safety and Health Administration (OSHA)
have made recommendations for protecting workers involved in avian
influenza outbreak disease control and eradication activities
concerning the respiratory protection, eye protection, and
protective clothing that should be worn and the hand-hygiene
practices that should be followed. (See
http://www.cdc.gov/flu/avian/protectionguid.htm and
http://www.osha.gov/dsg/guidance/avian-flu.html.)
The following information describes why respiratory protection, eye
protection, protective clothing, and hand-hygiene practices are
recommended for disease control and eradication activities and gives
guidance on selecting personal protective equipment for workers
responding to outbreaks of avian influenza. This information was
prepared as an aid to the development of biosecurity guidelines and
standard operating procedures for the various sectors of the poultry
industry.
The process of selecting an appropriate ensemble of personal
protective equipment requires an understanding of the work
activities associated with possible exposures; the health effects
that may result from exposure; properties of the virus (such as
whether it is low pathogenicity or high pathogenicity); host factors
(e.g., a worker's susceptibility and immunization status); and the
advantages, disadvantages, and protective capabilities of the
different types of personal protective equipment. Because changes to
the initial ensemble may occur during the course of a response to an
outbreak, the persons with responsibility for making revisions
should be identified in the biosecurity guidelines.
Respiratory Protection
Because infectious diseases such as avian influenza may be
transmitted by breathing contaminated dust, poultry workers should
wear respirators. Respirators that have filters or cartridges are
called air-purifying respirators. These types are the most practical
and appropriate choices for poultry workers to wear when they might
be exposed to infected birds or during day- to-day activities in
poultry barns. The table below lists the advantages, disadvantages,
and costs of the five types of air-purifying respirators in order of
increasing levels of protection. More information on the advantages
and disadvantages of different respirators and guidance on selecting
respirators for infectious agents can be found in the respirator
selection section of the CDC/NIOSH histoplasmosis guidelines at
http://www.cdc.gov/niosh/docs/2005-109. Also, for guidance on the
protective capabilities of respirators, see 2004 NIOSH Respirator
Selection Logic.
While all of the listed respirators can protect poultry workers,
they will not be protective unless all of the elements of a written
respiratory protection program are followed. Examples include
providing respirator training to workers and fit testing tight-
fitting facepieces to ensure a secure and comfortable face seal.
Also, every respiratory protection program must have an
administrator who is responsible for overseeing the program?s
functioning and who can answer questions workers might have about
respirator use; workers need to
be informed about who the program administrator is.
The need for respiratory protection presents a challenge to many
poultry workers, such as contract poultry growers and their
employees. Workers at risk of prolonged direct or indirect exposure
to any avian influenza virus in an enclosed setting should always be
included in a respiratory protection program.
Information describing all of the elements of a complete respiratory
protection program and the use of respirators can be found at
http://www.osha.gov/SLTC/respiratoryprotection/index.html.
Eye Protection
Eye protection will reduce direct exposure of the eyes to
contaminated dust and aerosols and help keep workers from touching
their eyes with contaminated fingers. To prevent the mucous
membranes of the eyes from being exposed to the avian influenza
virus, poultry workers should wear safety goggles or a respirator
that has a full facepiece, hood, helmet, or loose-fitting facepiece.
If safety goggles are worn, they should be nonvented (eyecup
goggles, for example) or, at a minimum, indirectly vented.
Properly fitted, indirectly vented safety goggles with a good
antifog coating may be a good choice for poultry workers who have
lower risks of exposure. However, such goggles are not airtight, and
consequently, they will not completely prevent exposures to airborne
material. Directly vented goggles and safety glasses will provide
limited protection, but are not recommended for protection against
fine particles, splashes, or aerosols such as required in situations
when workers will be exposed to infected birds.
Workers who wear prescription lenses should wear eye protection that
has the correction built into the safety lenses of the protective
eyewear, has lens inserts, or can be fitted over regular street-
wear prescription glasses without compromising eye or respiratory
protection. Although regular prescription glasses cannot be worn
with full facepiece respirators, they can be worn with some types of
powered air-purifying respirators (those with hoods and some with
helmets) and some styles of goggles. However, for goggles to be
effective they must fit snugly, especially from the corners of the
eyes across the brow. Additionally, protective eyewear should be
selected that does not interfere with the worker?s vision by
disturbing the proper position of the prescription lenses. Contact
lenses may be worn with goggles, safety glasses, or any respirator
and thus provide excellent corrective vision while maximizing the
protective eyewear selected.
Eye protection should be fitted together with a respirator because
some goggles can alter the fit of a half-facepiece respirator. To
ensure that the eye protection does not interfere with a facepiece
seal, it should be worn when half-facepiece respirators are fit
tested and when workers conduct seal checks each time they put on
the respirator.
Caution should also be used when removing eye protection to ensure
that contaminated equipment does not come in contact with the eyes
or other mucous membranes. Eye protection that is properly selected
and used will help prevent conjunctivitis (redness, swelling and
pain in the
eyes and eyelids). Poultry workers exposed to birds infected with
avian influenza should see a physician at the first signs of
conjunctivitis.
More information on eye protection for infection control and other
documents concerning eye safety are available at
http://www.cdc.gov/niosh/topics/eye/.
Protective Clothing and Hand-hygiene Practices
Protective clothing (which includes gloves, aprons, outer garments
or coveralls, and boots or boot covers) should be used to prevent
direct skin contact with contaminated materials and surfaces and
reduce the likelihood of transferring contaminated material outside
a poultry barn or work site. Disposable protective clothing is
preferred.
Because protective clothing can be more insulating than regular work
clothing, precautions should be taken to protect workers from the
effects of heat stress. For example, wearing a lightweight cotton
coverall might create less of a heat stress risk for a worker than a
chemical resistant suit. Additionally, workers should know the
symptoms of heat-stress- related illnesses and be able to take
appropriate measures to ensure that such illnesses do not occur.
Information concerning heat stress and possible solutions can be
found at http://www.osha.gov/SLTC/heatstress/.
When selecting gloves, whether disposable ones made of nitrile or
vinyl that are lightweight (a thickness of 8 to 12 mil) or ones that
are heavy duty (a thickness of 18 mil or greater) that can be reused
after being disinfected, factors to consider include a worker?s
activities, the importance of dexterity, and whether the gloves need
to be durable and resistant to tearing and abrasion. Regardless of
the type of glove selected, care is needed to ensure that wearing
protective gloves does not aggravate existing dermatitis or damage
healthy skin because of prolonged exposure to water or sweating
hands. For example, a thin cotton glove can be worn beneath a glove
to protect against dermatitis, which can occur from prolonged skin
exposure to moisture in gloves caused by perspiration.
Workers should always remove protective clothing (except for gloves)
first and discard or secure the clothing for disinfection before
removing their respirators and goggles. It is important that workers
understand the importance of strict adherence to hand washing after
contacting infected birds or surfaces that might be contaminated.
Having suitable hand-washing facilities and a good supply of soap
and disposable towels is essential. Before removing their gloves,
workers should wash their gloved hands thoroughly with soap and
water, and after removing the gloves, they should wash their hands
again. If hand-washing facilities are unavailable at the site of an
outbreak response, alternative hand-disinfection procedures will be
specified. If waterless soaps or alcohol-based sanitizers are
provided, care should be taken because they are very harsh on the
skin, which might lead to dermatitis if used too frequently.
It is important to take measures for preventing the avian influenza
virus from being spread to other areas. To do this, disposable items
of personal protective equipment should be discarded properly, and
non- disposable items should be cleaned and disinfected according to
outbreak-response guidelines.
Where to get more Information
Links to Internet sites are provided in this Safety and Health
Information Bulletin for those wanting more detailed information on
the topics presented. In addition, for those wanting sources of
personal protective equipment, manufacturers of protective clothing,
respirators, eye protection, and other items of personal protective
equipment are listed in the Buyer's Guide of the International
Safety Equipment Association at http://www.safetyequipment.org.
For answers to workplace safety and health questions, check the Web
sites of NIOSH or OSHA, or telephone NIOSH at (800) 356-4674 or OSHA
at (800) 321-6742.
Acknowledgements
This Safety and Health Information Bulletin is a product of the OSHA-
NIOSH Issues Exchange Group. Appreciation is extended for the
insightful reviews of this document by scientists from the National
Center for Infectious Diseases of the CDC and the Animal and Plant
Health Inspection Service of the U.S. Department of Agriculture.
Appreciation is also extended to Ms. Priscilla Wopat of the NIOSH
Spokane Research Laboratory for editing the document.
Disclaimer
Mention of company names or products does not constitute endorsement
by the National Institute for Occupational Safety and Health
(NIOSH), Centers for Disease Control and Prevention
(CDC).
Material contained in this document is in the public domain and
maybe reproduced, fully or partially, without the permission of the
Federal Government. Source credit is requested but not required.
Advantages, Disadvantages, and Costs of Air-purifying Respirators
for Protecting Poultry Workers
Respirator type Advantages Disadvantages Cost
(2004 dollars)
Filtering facepiece
(disposable;
dust mask) Lightweight.
No maintenance or cleaning needed.
No effect on mobility.
Provides no eye protection.
Provides no protection against irritant gases such
as ammonia.
Can add to heat burden.
Inward leakage at gaps in face seal.
Many models do not have adjustable head straps.
Difficult for a user to do a seal check.
Level of protection varies greatly among models.
Communication may be difficult.
Fit testing required to select proper facepiece size.
Some eyewear may interfere with facepiece fit.
$0.70 to $10
Elastomeric half-facepiece
Low maintenance.
Reusable facepiece and replaceable
filters and cartridges.
Dual cartridges can be used to protect workers from exposures to
particles, gases, and vapors.
No effect on mobility.
Provides no eye protection.
Can add to heat burden.
Inward leakage at gaps in face seal.
Facepiece must be cleaned and disinfected before
reuse, this can be a contact-exposure risk.
Communication may be difficult.
Fit testing required to select proper facepiece size.
Some eyewear may interfere with facepiece fit.
facepiece: $12 to $35
filters: $4 to $8 each
Powered with hood, helmet, or loose-fitting facepiece
Provides eye protection.
Protection for people with beards, missing
dentures, or facial scars.
Low breathing resistance.
Combination cartridges can be used for
exposures to particles, gases, and vapors.
Flowing air creates cooling effect.
Face seal leakage is generally outward.
Fit testing is not required.
Prescription glasses can be worn.
Communication less difficult than with rubber
half-facepiece or full-facepiece respirators.
Reusable components and replaceable filters.
Added weight of battery and blower.
Awkward to wear for some tasks.
Components must be cleaned and disinfected
before reuse; this can be a contact-exposure risk.
Battery requires charging.
Air flow must be tested with flow device before use.
unit: $400 to $1000
filters: $10 to $30
Elastomeric
full-facepiece with
N-100,
R-100, or P-100
filters Provides eye protection.
Low maintenance.
Reusable facepiece and replaceable filters
and cartridges.
Combination cartridges can be used for
exposures to particles, gases, and vapors.
No effect on mobility.
More effective face seal than that of filtering facepiece or rubber
half-facepiece respirators.
Can add to heat burden.
Reduced field-of-vision compared to half-facepiece.
Inward leakage at gaps in face seal.
Facepiece must be cleaned and disinfected before
reuse; this can be a contact-exposure risk.
Fit testing required to select proper facepiece size.
Facepiece lens can fog without nose cup
or lens treatment.
Spectacle kit needed for people who wear
corrective glasses.
facepiece: $90 to $240
filters: $4 to $8
each nose cup: $30
Powered with tight- fitting half-facepiece or
full-facepiece
Provides eye protection with full-facepiece.
Low breathing resistance.
Face seal leakage is generally outward.
Flowing air creates cooling effect.
Reusable components and replaceable filters.
Combination cartridges can be used for
exposures to particles, gases, and vapors.
Added weight of battery and blower.
Awkward to wear for some tasks.
No eye protection with half-facepiece.
Components must be cleaned and disinfected
before reuse; this can be a contact-exposure risk.
Fit testing required to select proper facepiece size.
Battery requires charging.
Communication may be difficult.
Spectacle kit needed for people who wear
corrective glasses with full-facepiece respirators.
Air flow must be tested with flow device before use.
unit: $500 to $1000
filters: $10 to $30
