268700 Bacterial diversity in bioaerosols from two petting zoos

Monday, October 29, 2012

Ketki Patel, MD MPH , Department of Epidemiology, College of Public Health, University of Nebraska Medical Center, Omaha, NE
Chandran Achutan, PhD , Department of Environmental, Agricultural and Occupational Health, College of Public Health, University of Nebraska Medical Center, Omaha, NE
Dinesh Chandel, PhD , Center for Global Health and Development, College of Public Health, University of Nebraska Medical Center, Omaha, NE
Shawn Gibbs, PhD, CIH , Department of Environmental, Agricultural and Occupational Health, College of Public Health, University of Nebraska Medical Center, Omaha, NE
Pinaki Panigrahi, MD, PhD , Center for Global Health and Development, College of Public Health, University of Nebraska Medical Center, Omaha, NE
Background: There have been reports of disease outbreaks among visitors of animal exhibits associated with close contact to animals. However, limited studies have described the diversity of bacterial aerosols in petting zoos. We described the bacterial diversity of these aerosols using molecular techniques. Methodology: This cross-sectional pilot study used convenience sampling across two petting zoos (one indoor and one outdoor) within 15-miles of Omaha, Nebraska, during fall 2011. Each petting zoo involved a test and control location. We performed fixed-site bioaerosol sampling using impingement at a constant flow rate of 12.5 liters per minute, for 60 minutes. The samples were analyzed by universal 16s rDNA PCR-based Denaturing Gradient Gel Electrophoresis (PCR-DGGE). Temperature and relative humidity were recorded at each sampling location. Information on feeding and cleaning practices, number and types of animals were documented. Fisher's exact test was applied to compare the bacterial diversity. Results: The predominant organisms identified by PCR-DGGE were Bacteroides spp., Staphylococcus spp., Streptococcus spp.,Enterococcus spp., Escherichia coli, Clostridium spp., and Bifidobacterium spp. While Staphylococcus aureus band was relatively intense in all samples, C. difficile was mainly traced in the outdoor setting. Further, C. difficile specific multiplex PCR revealed presence of (Tcd-B) toxin-B gene/s. A total of 20-26 DGGE bands displayed diversity of known and unknown bacterial species. However, the variation in bacterial profiles overall was not statistically significant. The mean temperature (and relative humidity) for the indoor and outdoor sites were 27C (27%) and 12 C (16.5%), respectively. Conclusion: Our results suggest that a mixed diversity of pathogenic and non-pathogenic bacteria may be present at animal exhibits. Petting zoo visitors may be at a potential risk of exposure to pathogens. Identification of pathogens such as S. aureus and toxigenic strains of C. difficile in animal exhibits is a public health concern and demands further research.

Learning Areas:
Environmental health sciences
Epidemiology
Occupational health and safety
Protection of the public in relation to communicable diseases including prevention or control
Public health biology

Learning Objectives:
Describe the diversity of bacterial aerosols using molecular techniques. Assessment of potential exposure to bacterial aerosols to visitors and workers in petting zoos/animal exhibits.

Keywords: Environmental Exposures, Pathogens

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: This study is a student project in the Department of Environmental, Agricultural and Occupational Health at UNMC College of Public Health. My research interests include environmental and occupational health, molecular epidemiology of infectious diseases, child health.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.