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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 --
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Sudden death without any signs
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Lack of coordination
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Purple discoloration of the wattles, combs, and legs
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Soft-shelled or misshapen eggs
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Lack of energy and appetite
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Diarrhea
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Swelling of the head, eyelids, comb, wattles, and hocks
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Nasal discharge
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Decreased egg production
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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
|
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