1. Swine workers: An emerging risk group for community-associated methicillin- resistant Staphylococcus aureus (MRSA)3070.0.4 Abby L. Harper, Michael J. Male, Raymond P. Scheibel, Blake M. Hanson, Tara C. Smith Department of Epidemiology, University of Iowa College of Public Health, Iowa City, IAABSTRACTBACKGROUNDRESULTS ANTIBIOTIC RESISTANCE PANEL Of those tested, all resistant to penicillin,Over the past decade, the epidemiology of Methicillin Resistant Staphylococcus aureus Human MRSA Prevalence by Farm oxacillin, tetracyclinemethicillin-resistant Staphylococcus aureus 80.0 MRSA is estimated to affect 94,360 people in the U.S.,75.0(MRSA) has undergone significant changes.leading to an estimated 18,650 deaths (1) 71.5 3/15 also resistant to erythromycin &70.0Once primarily a hospital-based clindamycinpathogen, MRSA is now found increasingly inPercent Colonized with MRSA MRSA had become the most frequent cause of skin and 60.0the community, and this bacterium has causedsoft tissue infections presenting to emergency53.6SUMMARY50.0serious infections in individuals with no history departments. (5 ) 50.0of hospitalization. Recent research has also 45.8Humans Individuals exposed to swine, especially inshown that swine and swine farmers areSwineconfinement operations, are at risk for MRSA Approximately 30% of the general population carries a 40.0 carriagecolonized with MRSA at high levels in thestrain of S. aureus.Netherlands and Canada. With Iowa raising 1630.0 25.0million hogs a year in a $4 billion a year MRSA is present in U.S. swine (11% tested MRSA carriage rate in the general population is 20.0 16.7 to date)industry, we set out to examine the prevalence of estimated to be approximately 1.5% (6)MRSA in swine from Iowa and Illinois. 10.010.0Therefore, we collected samples from swine on Swine workers tested had high carriage rate17 different farms (8 confinement, 9 antibiotic(31.4% overall, 44.3% in confinementMethicillin Resistant Staphylococcus aureus - Swine0.0free) in Iowa and Illinois. To date, no MRSA hasworkers) Dutch study finds persons exposed to swine at Farm 1Farm 3 Farm 6 Farm 9Farm 15been found on organic farms in Iowa. Nasal CONCLUSIONS increased risk of MRSA carriage (3) Farms not listed were negative for MRSA.swabs were taken from 408 swine. Overall Farm 1: humans (15/28), swine (176/246); Farm 3: humans (9/12), swine First identification of ST398 in the UnitedMRSA prevalence in swine was found to be 11% Dutch studies confirms that swine-associated MRSA had(11/24); Farm 6: swine (4/24); Farm 9: humans (2/4); Farm 15: humansStates(45/408). MRSA prevalence in confinement recently entered the human population, and is now (1/10), swine (6/24).swine was 24% (45/192). These results show responsible for >20% of all MRSA infections in The Swine are a reservoir for MRSAthat colonization of swine by MRSA is very Netherlands (4)common on the farm system we examined in the Farm 1: MRSA Prevalence in Pigs100 100100 Swine strains of MRSA may be transmitted toMidwestern U.S., adding to the concern about Canadian study finds MRSA commonly found in pigs in 90 exposed swine workersdomestic animal species as a reservoir of this Ontario, Canada (2) Percent of pigs colonized with MRSAbacterium. In addition to swine, nasal andpharyngeal swabs were taken from humans.80 STUDY LIMITATIONS No data available on MRSA carriage in swine in the U.S.Overall MRSA prevalence in humans was 34.1%63 This study is ongoing, additional herds need to(27/86). Humans working in confinement60 be sampled and further testing andoperations had a prevalence of 44.3% (27/61). 5050 characterization of MRSA isolates needs to beIndividuals exposed to swine, especially inSTUDY QUESTIONS STUDY PROTOCOL accomplished.confinement operations, are risk for MRSA 4036carriage. Additional studies are ongoing to No human non-swine exposed controls haveexamine is the prevalence of MRSA carriage in What the carriage rates of MRSA in rural been sampled yet.Iowa. specific swine herds within Iowa and Illinois? Population: 20 Swine-exposed individuals (n=86) and various aged Chain of transmission is currently unknown. What is the prevalence of MRSA carriage in swine (n=408) from 17 herds in Iowa and Illinois. 0swine farm workers on these same farms? 9 1215 1821 24 Adult FUTURE DIRECTIONS Further plans call for the sampling of at least 18 herds in Age of Pig (weeks) Which MRSA strains are found in these Iowa and Illinois 9 confinement facilities and 9organic/antibiotic free farms. More general study of MRSA in rural Iowapopulations as characterized by genotypic sub No MRSA found to date on organic farms in Iowatyping methods (MLST, PFGE, and SCCmec)? All isolates examined to date were pvl negative and found to be sequence type 398 by Population prevalence and strain types IRB / ICAUC approval was obtained prior to collection. MLST What is the relationship between human and - Same strain as in the Dutch and Canadian studies Animals other than swineswine strains of MRSA in Iowa? - Also found in Denmark and GermanyQuestionnaire data: Individuals completed questionnaires asking about swine Overall prevalence, swine: 45/408(11%) WORKS CITED What are the risk factors for colonization with Confinement swine: 45/192 (24%)MRSA in swine workers exposed to MRSAexposure and personal protective gear and practices. 1. Klevens RM, Morrison MA, Nadle J, Petit S, Gershman K, Raypositive swine? S, Harrison LH, Lynfield R, Dumyati G, Townes JM, CraigSWINE WORKER RESULTSAS, Zell ER, Fosheim GE, McDougal LK, Carey RB, Fridkin SK. Is colonization maintained over time? Clinical specimens: Invasive methicillin-resistant Staphylococcus aureus Swine Nasal swabs infections in the United States. JAMA. 2007;15:1763-71. Human - Nasal and throat swabs All isolates, worker and2. Khanna T, Friendship R, Dewey C, Weese JS. Methicillin swine, are ST398, a swine- resistant Staphylococcus aureus colonization in pigs and pigfarmers. Vet Microbiol. 2007. farming associated strain.3. Huijsdens XW, van Dijke BJ, Spalburg E, van Santen-VerheuvelLaboratory Methods:This has also been found inMG, Heck ME, Pluister GN, Voss A, Wannet WJ, de Neeling Isolation and identification MRSATheAJ. Community-acquired MRSA and pig-farming. Ann Clin Netherlands, Germany, DenMicrobiol Antimicrob. 2006;5:26. ChromAgar4. van Loo I, Huijsdens X, Tiemersma E, de Neeling A, van de Catalase mark and Canada. Sande-Bruinsma N, Beaujean D, Voss A, Kluytmans J. Coagulase Emergence of Methicillin-Resistant Staphylococcus aureus of OverallAnimal Origin in Humans. EID. 2007;13:1834-9. Staph Latex5. Moran GJ, Krishnadasan A, Gorwitz RJ, Fosheim GE, McDougal MRSA Latex prevalence, humans:LK, Carey RB, Talan DA. Methicillin-resistant Staphylococcus PFGE using both Smal and Eagl restriction27/86 (31.4%)aureus infections among patients in the emergency PVL gene via PCRdepartment. NEJM. 2006;355:666-674. Humans working in 6. Kuehnert MJ, Kruszon-Moran D, Hill HA, McQuillan spa typing via PCR and sequencing G, McAllister SK, Fosheim G, McDougal LK, Chaitram SCCmec type examined via multiplex PCR confinement: 27/61 (44.3%) J, Jensen B, Fridkin SK, Killgore G, Tenover FC. Prevalence ofStaphylococcus aureus nasal colonization in the UnitedPFGE of isolates using EagI enzyme (lanes 3-11States, 2001-2002. JID. 2006;193:172179. Available at:human, 12-14 swine). Lane 15: USA100. Lane 16:http://www.journals.uchicago.edu/doi/full/10.1086/499632.USA300. Lane 17: USA400.