DISSERTATION PROPOSAL Antibioticresistant Staphylococcus aureus Investigation of a

DISSERTATION PROPOSAL: Antibiotic-resistant Staphylococcus aureus: Investigation of a poultry reservoir Department of Occupational & Environmental Health Sept. 10, 2010 Abby L. H. Maples, MPH

Introduction Background � Significance Goals Specific Aims Limitations of Current Literature & Research Design & Methods Strengths & Limitations

Background Staphylococcus aureus � Signs & symptoms � Methicillin-resistant S. aureus (MRSA) Hospital 94, 000 infections (Klevens, 2007) 18, 000 deaths (Klevens, 2007) Community 1% of US population colonized (Graham, 2006; Kuehnert, 2006; Shorr, 2007) Livestock http: //www. medicinenet. com/mrsa_infection/page 2.

Antibiotic-resistant S. aureus & Animals S. aureus can cause infection in animals (Baptiste, 2005; De Neeling, 2007; Juhasz. Kaszanyitzky, 2007; Khanna, 2008; Smith, 2009; Van Loo, 2007; Weese, 2005; Weese, 2006) Role of humans � Transient carriers or reservoirs? Role of animals � Endemic? Swine herds studied Livestock-associated MRSA increasing

Antibiotic-resistant S. aureus in Environmental Samples Airborne transmission � Colonization role? Previous airborne transmission studies (Gibbs, 2004; Gibbs, 2006) Surface contamination Meat contamination (De Boer, 2009; Hanson, in press) http: //www. takepart. com/news/tag/anti-factory-farming

Goals Long-term goal � Understand ecology & epidemiology of antibioticresistant (Ab. R)S. aureus Objective � Characterize aureus ecology & epidemiology of Ab. R S. Central hypothesis � Workers in close proximity to poultry are at risk of occupational exposure to Ab. R S. aureus � Farmers in contact with poultry will be colonized with MRSA

Specific Aims 1. 2. 3. Establish the prevalence & molecular characteristics of Ab. R S. aureus on poultry farms Establish the prevalence & molecular characteristics of Ab. R S. aureus in poultry processing facilities Determine risk factors for presence of Ab. R S. aureus on farms or processing facilities

Limitations of Current Literature S. aureus is rapidly changing Previous studies in chickens did not include workers Epidemiologic studies in poultry have not been conducted in U. S. http: //www. sciencedaily. com/releases/2009/03/090316120846. htm

Preliminary Studies Prevalence of MRSA in Iowa & Illinois swine 18 swine farms in Iowa & Illinois (Smith, 2009) � 9 each – confined animal feeding operations (CAFOs) & antibiotic-free systems 5/18 (27. 7%) farms positive for MRSA � All CAFOs (55. 5%, 5/9) Prevalence in swine 43/428 (10. 0%) Prevalence in humans 29/89 (32. 6%) � Humans working at CAFOs (45. 3%, 29/64)

Research Design & Methods Farm Description � Broilers, layers, and turkeys � Estimate 40% (± 5. 0%) prevalence in poultry 95% confidence interval, 80% power = 600 animals 20 animals from 30 farms (10 each) Convenience Sample � Estimate Goal 1 -2 employees per farm to enroll 60 humans http: //newshopper. sulekha. com/turkey-farm_photo_1063248.

Research Design & Methods Continued Sample Collection � IRB & IACUC Approved � Humans Nasal & throat Swabs Comparison, non-exposed group � Poultry Choanal (palatine) cleft & cloaca swabs Air Sample Collection � 6 -stage Andersen Viable Cascade Impactor

Research Design & Methods Continued Processing Facility Sample Collection � Estimate 25% prevalence in processing facilities � Surface & worker swabs of facility Occupational Exposure Questionnaire � Animal exposure in last year � Demographic & behavioral questions Farm Owner/Manager Questionnaire � Farm-specific questions

Research Design & Methods Continued Bacterial Growth � 6. 5% Staph enrichment broth, CNA & CHROMagar Microbiology � Gram stain, catalase, coagulase, S. aureus latex agglutination assay � MRSA confirmed by penicillin binding protein presence

Diagnostic Schematic

Research Design & Methods Continued Molecular Typing � Spa typing � PVL PCR � Multilocus sequence typing (MLST) � Pulsed-Field Gel Electrophoresis (PFGE) Antibiotic Resistance Testing � Broth dilution (CLSI standards) � Tested for susceptibility

Research Design & Methods Continued Data and Statistical Analysis � Double-entry Excel, into databases Access, and Teleform Verifier � Unique specimen numbers � Multivariate modeling of risk factors (SAS) Logistic regression Cochran-Armitage trend test

Strengths & Limitations Strengths First study of S. aureus in live poultry & workers in US Well qualified & experienced team Collaboration with ISU Iowa is a national leader in eggs and turkey production Limitations Convenience, singletime samples (not representative) Pilot study Limited geography Limited farmer enrollment

Impact & Benefit to Field Assess infectious disease risks Provide recommendations for preventative measures Establish prevalence and dominant molecular types of S. aureus in poultry Create potential implementations to prevent spread of S. aureus in rural Iowa

Three Publishable Paper Topics Literature review of poultry diseases Antibiotic resistant Staphylococcus aureus: Investigation into a poultry reservoir Staphylococcus aureus in environmental samples and humans: Two poultry production facilities in Iowa(? ) Airborne Staphylococcus aureus in (10) poultry barns (? ) **Open for discussion

Project Timeline Oct 2010 – Sept 2011: Farm Sampling Dec 2010 – June 2012: Molecular analysis & antibiotic resistance testing June – Sept 2012: Finish analysis & draft manuscript Oct-Dec 2010 Jan-March April-June July-Sept Oct-Dec 2011 Jan. March 2012 April-June July-Sept 2012 Farm Sampling Molecular analysis & antibiotic resistance testing Finish analysis & draft manuscript

Questions, Comments, or Concerns? http: //ehsmanager. blogspot. com/2009/05/bacteria-create-aquatic-superbugs-

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