Online Program

Salmonella outbreak associated with animal exhibits at a county fair in Coconino County, Arizona

Sunday, November 1, 2015

Marilee Kellis, BS, Office of Infectious Disease Services, Arizona Department of Health Services, Phoenix, AZ
Brenna Garrett, BS, Office of Infectious Disease Services, Arizona Department of Health Services, Phoenix, AZ
Heidi Dragoo, MPH, Office of Infectious Disease Services, Arizona Department of Health Services, Phoenix, AZ
Mare Schumacher, Surveillance, Environmental Health, Response, and Vital Records, Coconino County Public Health Services District, Flagstaff, AZ
Marlene Gaither, RS, MPA, ME, Coconino County Public Health Services District, Flagstaff, AZ
Marie Peoples, PhD, Office of the Director
During September 2014, an increase in the number of reported Salmonella cases was detected in Coconino County. Ten cases were reported and interviewed with a standard questionnaire. Exposure to a county fair was noted for seven cases, held in Flagstaff, Arizona from Friday, August 29 through Monday, September 1, 2014. Illness onset for these cases ranged from September 4 to September 12.

All seven infections were due to Salmonella I 4[5],12:i:-. The PFGE patterns for six cases were indistinguishable. Nationally, multiple clusters of Salmonella cases with this PFGE pattern were previously investigated, identifying potential links to a county fair, live pig exposure, and pork products. The PFGE pattern for the seventh case differed by at least two banding patterns and was not included in this analysis.

Coconino County Public Health Services District (CCPHSD) and Arizona Department of Health Services (ADHS) developed an event-specific questionnaire that was administered to five of the six cases; one case was lost to follow-up. The questionnaire asked about exposures at the fair, such as contact with animals, food exposures, and hand washing practices. The questionnaire also included questions about exposures not related to the fair, such as participation in other agricultural events, exposure to nested eggs, and other animal contact.

Of five cases interviewed with the event-specific questionnaire, all reported visiting animal enclosures.  Four of the five cases claimed they touched animals in the enclosures, but one denied touching animals directly. All five cases denied washing hands after contact with animals. These findings, coupled with information about exposures previously linked to this PFGE pattern, suggest that animal exhibits were likely the source of infection.

The CCPHSD and ADHS recommended several practices to decrease transmission of Salmonella and other pathogens in the future, including: increase the availability of hand-washing stations; post signs at the entrance and exits of the animal exhibits advising visitors to avoid eating in the exhibits; post signs advising visitors to wash hands after visiting animal exhibits; and clean handrails and enclosures at animal exhibits that visitors might touch.

Learning Areas:

Administer health education strategies, interventions and programs
Environmental health sciences
Protection of the public in relation to communicable diseases including prevention or control
Public health or related laws, regulations, standards, or guidelines
Public health or related organizational policy, standards, or other guidelines

Learning Objectives:
Identify factors to consider when developing an event-specific focused questionnaire. Describe epidemiologic activities that are effective in outbreak investigations, for example PFGE testing combined with focused interviews. Discuss disease prevention activities recommended for county fairs and other agricultural events.

Keyword(s): Epidemiology, Environmental Health

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I am an excellent presenter and communicator of information. Just as importantly, I am a 14-year public health epidemiologist with experience in outbreak investigations ranging from tickborne relapsing fever in a children's camp to norovirus in a long-term care facility to salmonellosis associated with a chain chicken restaurant. The presentation is a cooperation between state and local health departments combining expertise from both organizations.
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.