CDC logoSafer Healthier People  CDC HomeCDC SearchCDC Health Topics A-Z
NIOSH - National Institute for Occupational Safety and Health

Skip navigation links Search NIOSH  |  NIOSH Home  |  NIOSH Topics  |  Site Index  |  Databases and Information Resources  |  NIOSH Products  |  Contact Us

NIOSH Safety and Health Topic:

Avian Influenza

close up of young broilers a poultry production facility day old chicks
Photos courtesy of U. S. Department of Agriculture


Avian influenza (or bird flu) is a poultry disease caused by viruses that normally infect birds. This disease is caused by a number of type A influenza viruses.

Domestic poultry may be infected with one of two types of avian influenza viruses:

  • The highly pathogenic viruses spread quickly and may kill nearly an entire poultry flock within 48 hours.
  • The low pathogenic viruses cause only mild symptoms in chickens (such as ruffled feathers or a drop in egg production).

These avian influenza viruses usually do not infect humans. However, cases have occurred in humans outside the United States. The disease can be transmitted to poultry workers or others who contact infected poultry or contaminated surfaces. Examples of workers at risk include the following:

  • Poultry growers and their workers
  • Service technicians of poultry processing companies
  • Caretakers, layer barn workers, and chick workers at egg production facilities
  • Workers involved in disease control and eradication (including Federal, contract, and company workers)

The first cases of human infection with the highly pathogenic avian influenza virus H5N1 occurred in 1997 in Hong Kong. This virus probably originated from domestic poultry in that region. The current outbreaks of the H5N1 virus began in Asia in 2003. The H5N1 virus was recently reported in birds in Europe and Africa. This highly pathogenic virus has not been reported in birds or humans in the United States.

Scientists are concerned about the highly pathogenic H5N1 virus for three reasons:

  1. It threatens domestic poultry, especially chickens, throughout the world.
  2. It has passed from poultry to humans and caused serious illness and death.
  3. It may change into a form that is highly infectious in humans and spreads easily from person to person.

The H5N1 virus is excreted in the droppings, saliva, and nasal secretions of infected birds. The virus is believed to enter humans through the mouth, nose, eyes, and lungs. Scientists believe that the virus has been transmitted to humans from contact with one of the following:

  • Infected poultry that was sick or dead
  • Droppings of infected poultry
  • Contaminated litter
  • Contaminated surfaces such as egg collection containers

Although the human health risk of exposure to low pathogenic avian influenza viruses is not known, protective measures should be taken for anyone likely to have prolonged exposure to any avian influenza virus in an enclosed setting.

CDC Avian Influenza Resources

NIOSH Alert: Protecting Poultry Workers from Avian Influenza (Bird Flu)
DHHS (NIOSH) Publication No. 2008-128 (2008)
Provides guidance to employers and workers about protecting poultry workers from exposure to avian influenza viruses (May 2008).
spanish Icon En Español

CDC Avian Influenza Home Page
Provides comprehensive information about avian influenza, including recent outbreaks, the viruses, and the risk to human health. Provides links to guidance for specific industries and workers.
spanish Icon En Español

CDC/Council of State and Territorial Epidemiologists (CSTE) Rapid Response Training: The Role of Public Health in a Multi-Agency Response to Avian Influenza in the United States
Provides course materials to guide state and local health departments in identifying and controlling human infections and illness associated with high pathogenicity avian influenza. Includes personal protective equipment information and a poultry farm investigation exercise (2007).
External link:

CDC Interim Guidance for States Conducting Avian Mortality Surveillance for West Nile Virus and/or Highly Pathogenic H5N1 Avian Influenza Virus
Provides guidance directed to state health departments to support avian mortality surveillance. Provides general precautions for collecting single dead birds, additional precautions for higher-risk settings, and recommendations for personal protective equipment disinfection and laboratory biosafety (August 2006).
this document in PDFPDF pdf file 3 pages 48KB

CDC Interim Recommendations for Persons with Possible Exposure to Avian Influenza During Outbreaks Among Poultry in the United States
Describes the 2004 avian influenza outbreak in Texas and provides interim guidance for persons who might be exposed to avian influenza; health-care professionals; and consumers of poultry (February 2004).
spanish Icon En Español

CDC Interim Guidance for Protection of Persons Involved in U.S. Avian Influenza Outbreak Disease Control and Eradication Activities
Provides interim guidance for protection of persons involved in activities to control and eradicate outbreaks of avian influenza among poultry in the United States (January 2006).
spanish Icon En Español

CDC Webcast Symposium on Avian Influenza for State Health Departments and Poultry Industry; Includes Worker Health and Safety Presentation
Provides transcripts and presentations on worker health and safety, the public health impact of avian influenza, food safety issues, and biosecurity on the farm by experts in public health and animal health (November 2004).

CDC Interim Guidance for Airline Flight Crews and Persons Meeting Passengers Arriving from Areas with Avian Influenza (Updated)
Informs airline flight crews and personnel meeting arriving passengers about appropriate precautions in the event they must interact with a person suspected of having avian influenza. Recommendations are based on standard infection control practices used in healthcare settings and on available information about the virus that causes avian influenza (March 2006).
spanish Icon En Español

CDC Interim Guidance for Airline Cleaning Crew, Maintenance Crew, and Baggage/Package and Cargo Handlers for Airlines Returning from Areas Affected by Avian Influenza A (H5N1)
Informs personnel who clean, maintain, or remove baggage or packages from commercial and cargo airlines about appropriate precautions related to avian influenza A (H5N1) (March 2006).
spanish Icon En Español

CDC Interim Guidance for Cleaning Aircraft Exteriors after Collisions with Birds in Avian Influenza A (H5N1)-Affected Areas
Provides workers with cleaning recommendations if a bird strike has occurred to an airplane taking off from, flying over, or landing in one of the H5N1-affected countries (July 2006).

Other U.S. Avian Influenza Resources

OSHA Safety and Health Information Bulletin: Avian Influenza: Protecting Poultry Workers at Risk
A product of the OSHA-NIOSH Issues Exchange Group that presents basic information about avian influenza viruses and describes measures for protecting and minimizing exposure of poultry workers to the virus (highlighted above).
External link:

OSHA Guidance for Protecting Workers Against Avian Flu
Provides updated guidance, quick cards, and a fact sheet about avian influenza. Information is provided for poultry, laboratory, and health care workers, animal handlers, food handlers, airport personnel, employees working abroad, and other worker groups at risk.
External link:

Department of Health and Human Services: Avian and Pandemic Health and Safety Page
Provides access to comprehensive U.S. government health and safety information about avian and pandemic influenza including worker resources.
External link:
spanish Icon En Español

U.S. Department of Agriculture (USDA) Avian Influenza Site
Provides news releases, fact sheets, and resources on avian influenza and highly pathogenic avian influenza.
External link:!ut/p/_s.7_0_A/7_0_1OB?navid=AVIAN_INFLUENZA&navtype=SU

USDA Animal and Plant Health Inspection Service (APHIS) Directive: Ensuring the Protection of Employees Involved in Highly Pathogenic Avian Influenza Control and Eradication Activities
Provides guidance for poultry workers, wildlife biologists, and veterinary laboratory workers (May 2006).
External link:

U.S. Department of Interior Employee Health and Safety Guidance for Avian Influenza Surveillance and Control in Wild Birds
Provides guidelines on personal protective equipment and work practices to reduce the risk of acquiring or transmitting avian influenza and other pathogenic agents when handling potentially infected wildlife (January 2007).
External link:

National Institute of Environmental Health Sciences (NIEHS) Worker Education Training Program (WETP) Avian Influenza Site
Provides resources for avian influenza outbreak responders and other workplace resources.
External link:

NIEHS WETP Avian Responder Conference Site
Provides presentations and information about protecting avian influenza outbreak responders from the September 2007 NIEHS WETP conference.
External link:

U.S. Geological Survey (USGS) National Wildlife Health Center (NWHC), Avian Influenza Site
Provides information about avian influenza in wild birds in the United States and around the world.
External link:

USGS NWHC Wildlife Health Bulletin 05-03: Safety Guidelines for Handling Wild Birds
Provides guidance for field biologists and others working with or handling wild birds with specific reference to highly pathogenic avian influenza (August 2005).
External link:

U.S. Environmental Protection Agency (EPA) Document: Disposal of Domestic Birds Infected by Avian Influenza: An Overview of Considerations and Options
Provides information about domestic bird carcass management options, equipment cleaning and disinfection, transportation, and personal protective equipment. Provides contact information for appropriate response organizations (August 2006).
External link:

U.S. EPA Fact Sheet: Antimicrobial Products to Disinfect Poultry and Other Facilities Against Avian Flu
Provides information about disinfectant products registered for use against avian influenza A viruses.
External link:
spanish Icon En Español

Delmarva Avian Influenza Joint Task Force, Interim Guidance for Implementation of CDC and OSHA Avian Influenza Recommendations
Provides interim guidance on worker training, infection control, use of personal protective equipment, decontamination, vaccine and antiviral use, surveillance for illness, and evaluation of persons who become ill.
External link:

National Chicken Council (NCC) Questions and Answers on Avian Influenza
Provides questions and answers on avian influenza from the NCC, the national, non-profit trade association representing the U.S. chicken industry.
External link:

Alaska Department of Fish and Game: What Hunters Should Know about Avian Influenza
Provides preventive recommendations for hunters working with wild birds.
External link:

U.S. Resources for Poultry Workers

OSHA Fact Sheet: Avian Flu
External Link:

OSHA Quick Card for Poultry Employees: Protecting Yourself from Avian Flu
External Link:

NIEHS WETP Booklet: Protecting Yourself from Avian Influenza
An awareness level health and safety resource for workers who might contact avian influenza-infected animals or contaminated materials.
External Link to Cover:
External Link to Booklet:

USDA APHIS Biosecurity Site
Provides information about biosecurity practices for poultry, pet birds, and wild birds with tools such as fact sheets, booklets, brochures, and posters.
External link:

Delmarva Avian Influenza Joint Task Force: Answers to Common Questions about Avian Influenza for Poultry Growers
Provides information about biosecurity, infection control, and prevention recommendations.
External link:

University of Maryland: Understanding Avian Influenza
Provides farm and business resources including biosecurity recommendations for specific groups of poultry workers such as vaccination crews, live-haul crews, and technical service workers.
External link:

International Avian Influenza Resources

Disclaimer: These resources are developed by government agencies whose safety and health practices and recommendations may differ from those of the United States

World Health Organization (WHO) Avian Influenza Site
Provides international guidelines, recommendations, reports, and updated information on the status and impact of avian influenza activities and outbreaks around the world.
External link:
spanish Icon En Español

WHO Avian Influenza Interim Infection Control Guidelines for Health Care Facilities
Provides comprehensive guidelines for health care facility exposures, including personal protective equipment recommendations.
this document in PDF
PDF pdf file 58 pages 211KB
External link:

WHO Aide-Memoire (Memory Aid): Infection Control Recommendations for Avian Influenza in Health Care Facilities
Provides concise recommendations about infection control for avian influenza.
this document in PDFPDF pdf file 2 pages 1.17MB
External link:

WHO Interim Guidelines for the Protection of Persons Involved in the Mass Slaughter of Animals Potentially Infected with Highly Pathogenic Avian Influenza Viruses
Provides guidelines for worker protection including appropriate personal protective equipment.
this document in PDFPDF pdf file 1 page 765KB
External link: Influenza.pdf

WHO Guide for Field Operations: Collecting, Preserving and Shipping Specimens for the Diagnosis of Avian Influenza A(H5N1) Virus Infection
Provides worker safety information including recommendations for hand hygiene technique, respiratory protection, and disinfection (October 2006).
External link:

World Organization for Animal Health (OIE) Avian Influenza Site

Provides information about the global distribution of avian influenza and methods of controlling the disease in animals.
External link:
spanish Icon En Español  

Food and Agriculture Organization of the United Nations (FAO) Avian Influenza Site
Provides information about avian influenza related to improved food security, food safety, and safe trade in poultry and poultry products. Provides information in support of the efforts to control highly pathogenic avian influenza in Asian countries.
External link:

spanish Icon En Español 

European Centre for Disease Control and Prevention (ECDC) Avian Influenza Page
Provides scientific and technical guidance on avian influenza including current guidelines on occupational exposure.
External link:

ECDC Guidelines to Minimise the Risk of Humans Acquiring Highly Pathogenic Avian Influenza From Exposure to Infected Birds or Animals
Provides guidance for protecting workers from avian influenza exposure (December 2005).
this document in PDFPDF pdf file 11 pages 715KB
External link:

United Kingdom Health and Safety Executive (HSE): Working with Highly Pathogenic Avian Influenza Virus
Provides guidance for workers and answers questions related to occupational exposure.
External link:

HSE Guidance Document: Avoiding the Risk of Zoonotic Infections When Working with Poultry That is Not Suspected of Having Avian Influenza
Provides guidance for avoiding occupational infection with avian influenza
this document in PDFPDF pdf file 2 pages 41.7KB
External link:

HSE Guidance Document: Avoiding the Risk of Zoonotic Infections When Working with Poultry That is Suspected of Having Highly Pathogenic Avian Influenza
Provides guidance for avoiding infection when working with infected poultry.
this document in PDFPDF pdf file 4 pages 92KB
External link:

International Resources for Poultry Workers

Disclaimer: These resources are developed by government agencies whose safety and health practices and recommendations may differ from those of the United States

WHO Preventing Bird Flu: Precautions Poultry Farm Workers Should Take
External Link:

FAO Avian Influenza Farming Systems Documents
Provides guidance for the prevention and control of avian influenza in small scale poultry. Documents are available in many languages and written for different countries including Cambodia and Vietnam.
External Link:
spanish Icon En Español 

FAO: Protect Poultry, Protect People: Basic Advice for Stopping the Spread of Avian Flu
Provides advice for workers and others to minimize animal-to-animal and animal-to-human spread of disease.
this document in PDFPDF pdf file 11 pages 70.3KB
External link:

Academy for Educational Development Avian and Pandemic Influenza Behavior Change Communication Tools
Provides brochures, fact sheets, and posters for farmers in different countries.
External Link:

Related NIOSH Publications and Presentations

Avian Influenza: Worker Health and Safety (Presentation)

Disclaimer: The findings and conclusions in this presentation are those of the author and do not necessarily represent the views of the National Institute for Occupational Safety and Health

this document in PDFPDF only pdf file 22pages 211KB
NIOSH presentation at the North Atlantic Poultry Health and Management Conference, Windsor Locks, Connecticut, May 10, 2005. This presentation includes avian influenza information about responder recommendations, medical guidance for poultry workers, and guidance on personal protective equipment.

Histoplasmosis — Protecting Workers at Risk
DHHS (NIOSH) Publication No. 2005-109 (2004)  
This revised booklet provides updated information about worker exposure to the disease-causing fungus Histoplasma capsulatum. It provides information about histoplasmosis, identifies activities that may put workers at risk, and provides recommendations for disease prevention and protection of workers.
spanish Icon En Español  

NIOSH Respirator Selection Logic 2004
DHHS (NIOSH) Publication No. 2005-100 (2004)
This document provides guidance to respirator program administrators on respirator selection. It incorporates the changes necessitated by the revisions to the respirator use and certification regulations and changes in NIOSH policy. This guidance is not intended to be used for the selection of respirators to protect against infectious agents or chemical, biological, radiological or nuclear agents of terrorism.

Interim Recommendations for the Selection and Use of Protective Clothing and Respirators Against Biological Agents
DHHS (NIOSH) Publication No. 2002-109 (2001)
This document contains recommendations for personal protective equipment used in given exposure conditions based on current understanding at the time of publication.

Related NIOSH Safety and Health Topics

Aerosols Topic Page
Provides links to information regarding the measurement, control, exposure characterization and health effects associated with aerosols in the workplace.

Agriculture Topic Page
Provides links to publications on agricultural topics including ergonomics, grain handling, injuries and deaths, machinery, and young workers. Provides links to additional agricultural resources.

Eye Protection for Infection Control
Provides information on types of eye protection for a variety of exposure settings where workers may be at risk of acquiring infectious diseases via ocular exposure.

Infectious Aerosols Topic Page
Provides links to resources to aid workers and employers in reducing exposures to infectious aerosols.

Protective Clothing Topic Page
Provides information about protecting the skin from various health hazards that may be encountered in the workplace or during a terrorist attack.

Respirators Topic Page
Provides information about respirators including selection, cleaning and maintenance, certification, standards and rulemaking, user notices, and other resources.

Severe Acute Respiratory Syndrome (SARS)
Provides a compilation of workplace resources about SARS.

Understanding Respiratory Protection Against Severe Acute Respiratory Syndrome (SARS)

Provides information about personal protective equipment and techniques to prevent exposure to SARS, and the spread of contaminated materials.

West Nile Virus Topic Page
Provides information about the West Nile virus, identifies workers at risk, and provides recommendations for prevention of worker exposure.

Page last modified: September 5, 2008
Page last reviewed: June 5, 2008
Content Source: National Institute for Occupational Safety and Health (NIOSH)

Avian Influenza

close up of a chicken

On This Page...

CDC Resources
Other U.S. Resources
 U.S. Resources For Poultry Workers
International Resources
 International Resource For Poultry Workers
NIOSH Publications Presentations
Related NIOSH Safety and Health Topics