Health hazard evaluation report: HETA-98-0339-2806, United States Department of Agriculture, Animal and Plant Health Inspection Service, Riverdale, Maryland.
In response to a September 1998 request from the United States Department of Agriculture, Animal and Plant Health Inspection Service (USDA/APHIS), a health hazard evaluation was conducted to assess potential zoonotic disease hazards encountered during animal welfare inspections. During the period January 25 to March 24, 1999, site visits were made to 16 facilities in the Eastern and Western regions to observe animal welfare inspections at businesses licensed by or registered with USDA. The businesses visited included research facilities, animal dealers, exhibitors, and breeders. National Institute for Occupational Safety and Health (NIOSH) investigators observed work practices, personal protective equipment use, and the extent and duration of contact with the animals during the inspections. Interviews were conducted with inspectors and other APHIS personnel, and various health and safety documents were reviewed. The inspections revealed a wide variation in environmental conditions and potential zoonotic disease hazards at these facilities. There was potential for exposure to infectious materials via mucous membrane contact, airborne exposure, direct contact (bites, scratches) and indirect contact. Contact with nonhuman primates was of greatest concern to the inspectors because of the similarities in pathogen susceptibility and the potential for acquiring medically important infections such as tuberculosis (TB) and B Virus. Efforts were generally made by the inspectors to maintain a safe distance from the animals when possible; in some cases inspections were conducted outdoors or from behind a clear barrier. However, at several facilities the inspectors encountered hidden hazards (such as unrestrained animals), poor environmental conditions (such as inadequate lighting or insufficient caging materials), or the presence of undisclosed animals. While baseline serum samples are collected from some USDA employees at the time of employment for evidence of prior brucellosis or psittacosis infection, the extent of participation by animal welfare inspectors was not known. Routine tuberculin skin testing for TB (either annually or semiannually) is required for all animal welfare inspectors, but sufficient information could not be obtained to determine TB infection or conversion rates, or to evaluate whether the tests had been conducted and interpreted according to current Centers for Disease Control and Prevention (CDC) guidelines. Illness and injury logs revealed nonspecific information on infectious diseases reported among APHIS personnel. APHIS employees may be exposed to zoonotic agents during animal welfare inspections. Improved prevention efforts to eliminate or minimize such exposures are needed. Because engineering controls are not often available at the inspected facilities, inspectors must rely primarily on administrative and work practice controls and, secondarily, on the use of personal protective equipment to minimize exposures. Available medical surveillance data were too limited to fully evaluate the risk of infection and effectiveness of current prevention efforts. Recommendations are made in the report to strengthen the zoonotic disease prevention program for animal welfare inspectors.