posted March 1, 2005
These may all be signs of asthma. The disease in humans is much the same as in animals; the airway becomes inflamed and muscles in the airway tighten as the airway tissue swells. As a result, breathing becomes difficult.
If these symptoms worsen throughout the workweek and improve while away from the job, occupational asthma may be the culprit.
According to the American Academy of Allergy, Asthma, and Immunology, occupational asthma has become the most prevalent work-related lung disease in developed countries. The National Institute for Occupational Safety and Health estimates that 10 percent of animal handlers, including veterinarians, researchers, and laboratory and veterinary technicians, have symptoms of animal-induced asthma.
Veterinarians are at risk for occupational asthma because many animal substances, including hair, dander, mites, small insects, and bacterial or protein dusts, are known asthma triggers. In many cases, a personal or family history of allergies increases an individual's susceptibility.
In the early stages of occupational asthma, the symptoms may occur only at work, and usually decrease or disappear away from work. But if undiagnosed and untreated, the disease may progress to the point where symptoms can occur at any time and any place. Once the airways have developed a pattern of reacting to the original irritant in the workplace, other common substances, such as cigarette smoke or dust, could trigger symptoms.
Laboratory animals and companion animals are the most common culprits in animal-induced asthma. Veterinarians who work with production animals have also been shown to develop wheezing and chronic coughing. This is a particular problem for those who work in large confinement areas without adequate ventilation, because confinement barns often have airborne endotoxins, bacteria, dust, and ammonia concentrations sufficient to affect pulmonary function. Horsehair and dander are also potent allergens. Occupational exposure to horses may also increase sensitization, which may induce allergic symptoms and asthma.
Although most veterinarians and others who work with animals will, fortunately, not develop asthma as a result of exposure to animals, the problem is one that every animal facility should still address proactively. NIOSH has published a series of measures recommended to reduce exposures to animal allergens in the workplace to help prevent animal-induced asthma. The recommendations, which are specific to the laboratory setting, include ideas that can be implemented in the practice setting as well.
Adequate ventilation is one of the key recommendations. NIOSH recommends several modifications to ventilation and filtration systems (see bullet points on page 861).
Housekeeping is also important. Keep animal areas clean, and take care to control exposures when cleaning. Dust surfaces regularly with a damp cloth. Use a vacuum instead of a broom. Use absorbent pads for bedding, if possible.
Avoid carpets, fabric wall coverings, overstuffed furniture, and drapes to help reduce allergens in the workplace. Washable surfaces are best, as are floors that are wood, tile, or linoleum. After mopping floors, use clean water to rinse away chemicals.
Personal habits can also help control the risk of exposure. Laboratory veterinarians can reduce skin contact with animal products such as dander, serum, and urine by using gloves, laboratory coats, and approved particulate respirators with face shields. All veterinarians can benefit by washing hands frequently, not wearing street clothes at work, and leaving work clothes at work. If possible, launder work clothes at the workplace.
Because early intervention is critical to preventing long-term lung damage, veterinarians and others who work with animals should not only practice preventive measures in the workplace, but also be alert to both asthma and allergy symptoms. It is vital to seek medical care to receive a proper diagnosis and to determine the correct course of care.
An article published in the Journal of Allergy and Clinical Immunology underscores the importance of awareness and prevention. The article advises periodic medical screening and allergy skin testing of all laboratory animal workers, since 20 percent to 30 percent of workers suffering allergy symptoms will go on to develop true occupational asthma.
Veterinarians who experience symptoms should consult their physician. A routine wellness examination provides an excellent opportunity to discuss these concerns. The AVMA GHLIT has an upgraded Wellness Benefit on many plans to encourage veterinarians to be more proactive about their health.
Excellent ventilation, superb housekeeping, and careful personal habits can mitigate the problem for many veterinarians, but not all. Dr. Steve Orme and Dr. Carol McConnell, AVMA GHLIT participants and colleagues at Veterinary Pet Insurance, are two veterinarians who left their practices and pursued other avenues in the profession because of animal-induced respiratory problems.
Dr. Orme practiced for many years, but unfortunately, left his practice after trying to resolve his respiratory problem through everything from air filtration systems to the wearing of masks and gloves. Dr. McConnell, on the other hand, realized just three years into her practice that she needed to make a decision to either try to deal with the allergens that were causing her asthma, or find a way to avoid the allergens in the first place. She decided to return to school to take her career in a different direction.
Dr. Orme points out that animal dander and hair are not the only potential culprits for respiratory problems. He also believes that veterinarians, over time, may experience considerable workplace exposure to insecticides. Also, the very products used to clean the offices to keep the environment healthy for pets can cause problems for the humans who are exposed to them on a daily basis. Advances in flea and tick protection as well as stricter enforcement of OSHA regulations are making veterinary offices safer, but every professional needs to remain vigilant about chemical exposure to in the course of their work.
For a great number of veterinarians and other animal handlers who are susceptible to animal allergens, implementing the NIOSH recommendations and other preventive measures may be all that is necessary to mitigate the problem. Others may be able, with medical intervention, to continue practicing without permanent adverse health effects.