Marin Schweizer, PhD

Marin Schweizer, PhDCo-Associate Director for Workforce Development

Associate Professor, Internal Medicine - General Internal Medicine

Associate Professor, Epidemiology

Personal Statement

Over the past 8 years, our research group has had continuous funding through AHRQ and VA to evaluate nasal decolonization interventions to prevent S. aureus infections. Through 2 AHRQ funded grants (PI: Herwaldt) and a VA CREATE grant (PI: Perencevich), we have successfully performed multicenter decolonization studies to prevent S. aureus infections among surgical patients and to qualitatively evaluate barriers and facilitators to this intervention. Results from the first AHRQ study were published in BMJ and JAMA. I played an integral role on each of these studies.

For the AHRQ studies, I was part of the implementation team that worked out the day-to-day implementation issues, I was a “coach” on the coaching calls, I created and compiled important tools for the toolkits, and I played an active role in each step of the statistical analyses and writing of the manuscripts.

For the VA study, I led the implementation of the intervention, was the main “coach” on the coaching calls, performed site visits, answered all questions from the sites, and am currently leading the statistical analysis.

My VA HSR&D career development award (PI: Schweizer) focused on the prevention and treatment of S. aureus infections.

I was recently awarded a VA IIR grant (PI: Schweizer) to create an intervention to de-implement chronic antibiotics among patients who experienced orthopedic surgical site infection but are at low-risk for recurrent infection. I have been actively involved in CDC Epicenter projects for the past 3 years and I greatly enjoy collaborating with colleagues at University of Illinois at Chicago, Emory Healthcare, University of Pennsylvania and Washington University (all Epicenter sites).

Of note, I have received formal correspondence from the University of Iowa that states that I will be promoted to Tenured Associate Professor as of July 2018. This application builds logically on my prior work, which focused on the epidemiology of S. aureus infections; nasal decolonization and other interventions to prevent surgical site infections; molecular epidemiology of S. aureus; meta-analyses of these topics; and analyses of large databases to evaluate healthcare-associated infections. Examples from my 82 publications are described below.


  • Biochemistry, Cell and Molecular Biology BS – Drake University, 2005
  • Epidemiology PhD – University of Maryland, 2009
  • Healthcare Outcomes Postdoctoral – University of Maryland, 2010


  • Postdoctoral Fellow, Division of Healthcare Outcomes Research, University of Maryland, School of Medicine, Baltimore, MD (2009-2010)
  • Associate, University of Iowa, Division of General Internal Medicine, University of Iowa, Carver College of Medicine, Iowa City, IA (2010-2012)
  • Assistant Professor, University of Iowa, Division of General Internal Medicine, University of Iowa, Carver College of Medicine, Iowa City, IA (2012-Present)
  • Investigator, Center for Comprehensive Access & Delivery Research and Evaluation, Iowa City VA Health Care System (2013-Present)

Professional Memberships

  • National Education Committee, Society for Healthcare Epidemiology of America (2010-2012)
  • National Research Committee, Society for Healthcare Epidemiology of America (2013-Present)
  • VA Quality Enhancement Research Initiative (QUERI) Rapid Response Project Review Committee (2013-2014)
  • Associate Editor, Antimicrobial Resistance and Infection Control (2014-Present)
  • Society for Healthcare Epidemiology of America, Annual Conference Program Planning Committee (2016-Present)
  • Society for Healthcare Epidemiology of America, Research Network Leadership Team (2016-Present)


  • Trudy Bush Research Award, University of Maryland, Dept of Epidemiology, Baltimore, MD (2008)
  • Graduate Program in Life Sciences PhD Thesis Project Honorable Mention. University of Maryland School of Medicine, Baltimore, MD (2009)
  • Pfizer ASPIRE Young Investigator Award (2010)
  • Best Clinical/Translational Poster: “A Multicenter Intervention to Reduce Surgical Site Infections Among Patients Undergoing Cardiac Operations and total Joint Arthroplasty (STOP SSI Study).” 49th Annual Department of Internal Medicine Research Day, University of Iowa, Iowa City, IA. (2015)​
  • 26th annual ECCMID Conference Travel Grant – Amsterdam, Netherlands (2016)

Contribution to Science

Epidemiology of S. aureus infections

My graduate work and my VA career development award have focused on the epidemiology of S. aureus infections and comparative effectiveness of treatment for S. aureus infections. I have mentored three graduate students on large retrospective studies evaluating patients with S. aureus infections in 122 VA hospitals.

  • Schweizer, M.L., Furuno, J.P., Harris, A.D., Johnson, J.K., Sakoulas, G., Shardell, M.D., McGregor, J.C., Thom, K.A., Cosgrove, S.E., & Perencevich, E.N. Comparative effectiveness of nafcillin or cefazolin versus vancomycin in methicillin-susceptible Staphylococcus aureus bacteremia. BMC Infectious Diseases. 2011;11:279. PMID: 22011388​
  • Albertson, J., McDanel, J.S., Carnahan, R., Chrischilles, E., Perencevich, E.N., Goto, M., Jiang, L., Alexander, B., & Schweizer, M.L.  Determination of risk factors for recurrent methicillin-resistant Staphylococcus aureus bacteremia in a Veterans Affairs Healthcare System population. Infection Control and Hospital Epidemiology. 2015;36(5):543–549. PMID: 25682861​
  • McDanel, J.S., Perencevich, E.N., Diekema, D.J., Herwaldt, L.A., Smith, T.C., Chrischilles, E.A., Dawson, J.D., Jiang, L., Goto, M., & Schweizer, M.L. Comparative effectiveness of beta-lactams versus vancomycin for treatment of methicillin-susceptible Staphylococcus aureus bloodstream infections among 122 hospitals. Clinical Infectious Diseases. 2015;61(3):361-7. PMID: 2590017​
  • Goto, M., Schweizer, M.L., Vaughan-Sarrazin, M.S., Perencevich, E.N., Livorsi, D.J., Diekema, D.J., Richardson, K.K., Beck, B.F., Alexander, B., & Ohl, M.E. Association of Evidence-Based Care Processes With Mortality in Staphylococcus aureus Bacteremia at Veterans Health Administration Hospitals, 2003-2014. JAMA Internal Medicine. 2017;177(10). PMID: 28873140

Surgical site infections

I have collaborated on multiple large studies evaluating interventions to prevent surgical site infections and associated poor outcomes. We have had continuous funding for the past 8 years to develop (Schweizer BMJ above in Personal Statement and Braun below), implement (Schweizer JAMA above in Personal Statement) and evaluate a bundled decolonization intervention to prevent S. aureus surgical site infections. Our 20-hospital pragmatic, quasi-experimental study found a 42% reduction in complex S. aureus surgical site infections. We are now implementing that bundle at 10 VA hospitals through the VA CREATE grant (PI: Perencevich). Additionally, I performed multiple meta-analyses and cohort studies on the burden of poor surgical outcomes and methods to prevent them, and wrote multiple invited reviews on this topic.

  • Braun, B.L., Herwaldt, L., Schweizer, M., Hafner, J.M., Moody, J., Richards, C.L., Ward, M.A., Hickok, J., Perencevich, E., & Septimus, E. Development and implementation of a consensus algorithm to optimize preoperative antimicrobial prophylaxis and decrease gram-positive surgical site infections for cardiac and orthopedic procedures., Agency for Healthcare Research and Quality. 2014 June;AHRQ Pub. No. 14-0003:33-56.​
  • Branch-Elliman, W., Ripollone, J.E., O'Brien, W.J., Itani, K.M., Schweizer, M.L., Perencevich, E., Strymish, J., & Gupta, K. Risk of surgical site infection, acute kidney injury, and Clostridium difficile infection following antibiotic prophylaxis with vancomycin plus a beta-lactam versus either drug alone: A national propensity-score-adjusted retrospective cohort study, PLOS Medicine. 2017 July;14(7):e1002340. PMID:28692690.
  • Chiang, H.Y., Herwaldt, L.A., Blevins, A., Cho, E., & Schweizer, M.L. Effectiveness of local vancomycin powder to decrease surgical site infections: a meta-analysis. The Spine Journal. 2014;14(3):397-407. PMID: 24373682​
  • Formanek, M.B., Perencevich, E.N., Herwaldt, L.A., & Schweizer, M.L. Gentamicin/collagen sponge use may reduce the risk of surgical site infections for patients undergoing cardiac operations: a meta-analysis. Surgical Infections. 2014;15(3):244-55. PMID: 24773201

Molecular epidemiology of S. aureus infections

My graduate work also included assessing the molecular epidemiology of S. aureus infections. When I become a faculty member at the University of Iowa, I mentored students on projects that evaluated the molecular epidemiology of S. aureus infections.

  •  Schweizer, M.L., Furuno, J.P., Sakoulas, G., Johnson, J.K., Harris, A.D., Shardell, M.D., McGregor, J.C., Thom, K.A., & Perencevich EN. Increased Mortality with Accessory Gene Regulator (agr)-Dysfunction in Staphylococcus aureus among Bacteremic Patients, Antimicrobial Agents and Chemotherapy. 2011;55(3):1082-7. PMID:21173172.​
  • McDanel, J.S., Perencevich, E.N., Diekema, D.J., Winokur, P.L., Johnson, J.K., Herwaldt, L.A., Smith, T.C., Chrischilles EA, Dawson JD, & Schweizer ML. Association between microbial characteristics and poor outcomes among patients with methicillin-resistant Staphylococcus aureus pneumonia: a retrospective cohort study, Antimicrobial Resistance and Infection Control. 2015;4:51. PMID:26668737. ​
  • Eko, K.E., Forshey, B.M., Carrel, M., Schweizer, M.L., Perencevich, E.N., & Smith, T.C. Molecular characterization of methicillin-resistant Staphylococcus aureus (MRSA) nasal colonization and infection isolates in a Veterans Affairs hospital, Antimicrobial Resistance and Infection Control. 2015;4:10. PMID:25838886. 
  • Le, J., Dam, Q., Schweizer, M., Thienphrapa, W., Nizet, V., & Sakoulas, G. Effects of vancomycin versus nafcillin in enhancing killing of methicillin-susceptible Staphylococcus aureus causing bacteremia by human cathelicidin LL-37, European Journal of Clinical Microbiology & Infectious Diseases. 2016;35(9):1441-7. PMID:27234592. 

Systematic literature reviews and meta-analyses

I have received funding from AHRQ, VA and CDC to perform systematic literature reviews and meta-analyses of interventions to prevent healthcare-associated infections. For the past 4 years, I have been the course master for a meta-analysis class at the University of Iowa. I also have been asked to lecture on meta-analysis methods nationally.

  • Schweizer, M.L., Reisinger, H.S., Ohl, M., Formanek, M.B., Blevins, A., Ward, M.A., & Perencevich, E.N. Searching for an optimal hand hygiene bundle: a meta-analysis. Clinical Infectious Diseases. 2014;58(2):248-59. PMID: 24107409​
  • Schweizer, M.L., Bossen, A., McDanel, J.S., & Dennis, L.K. Staphylococcus aureus colonization before infection is not associated with mortality among S. aureus infected patients: a meta-analysis. Infection Control and Hospital Epidemiology. 2012;33(8):796-802. PMID: 22759547​
  • Feazel, L.M., Malhotra, A., Perencevich, E.N., Kaboli, P., Diekema, D.J., & Schweizer, M.L. Effect of antibiotic stewardship programs on Clostridium difficile incidence: a systematic review and meta-analysis. The Journal of Antimicrobial Chemotherapy. 2014;69(7):1748-54. PMID: 24633207
  • Nair, R., Ammann, E., Rysavy, M., & Schweizer, M.L. Mortality Among Patients with Methicillin-Resistant Staphylococcus aureus USA300 Versus non-USA300 invasive infections: a Meta-Analysis, Infection Control and Hospital Epidemiology. 2014 January;35(1):34-41. PMID:24334796.

Analyzing large databases

As a PhD trained epidemiologist, I am comfortable with analyzing large databases of patient records to evaluate the epidemiology of infections and how they are treated. I started this work by analyzing data from the University of Maryland Medical Center, then went on to analyze other large datasets such as The Surveillance Network national data, and large VA datasets, including data collected for my career development grant. 

  • Schweizer, M.L., Eber, M.R., Laxminarayan, R., Furuno, J.P., Popvich, K.J., Hota, B., Rubin, M.A., & Perencevich, E.N. Validity of ICD-9-CM coding for identifying incident methicillin-resistant S. aureus (MRSA) infections: Is MRSA coded as a chronic disease? Infection Control and Hospital Epidemiology. 2011;32(2):148-154. PMID: 12460469​
  • Schweizer, M.L., Cullen, J.J., Perencevich, E.N., & Vaughan Sarrazin, M.S. Costs associated with surgical site infections in Veterans Affairs hospitals. JAMA Surgery. 2014;149(6):575-581. PMID: 24848779​
  • Schweizer, M.L., Perencevich, E.N., Eber, M.R., Cai, X., Shardell, M.D., Braykov, N., & Laxminarayan, R. Optimizing Antimicrobial Prescribing:  Are Clinicians Following National Trends in Methicillin-resistant Staphylococcus aureus (MRSA) Infections Rather than Local Data When Treating MRSA Wound Infections? Antimicrobial Resistance and Infection Control. 2013 Oct 15;2(1):28. PMID: 2412842​
  • McDanel, J.S., Roghmann, M., Perencevich, E.N., Ohl, M.E., Goto, M., Livorsi, D.J., Jones, M., Albertson, J.P., Nair, R., O'Shea, A.M., & Schweizer, M.L. Comparative Effectiveness of Cefazolin versus Nafcillin or Oxacillin for Treatment of Methicillin-Susceptible Staphylococcus aureus Infections Complicated by Bacteremia: A Nationwide Cohort Study, Clinical Infectious Diseases. 2017;65(1):100-106. PMID: 28379314

Published Works


Ongoing Research Support

  • VA HSR&D IIR 16-245

Schweizer (PI)                                                                    


Chronic Antibiotic Suppression after Prosthetic Joint Infection: A Target for De-implementation

This VA Merit Award has 3 aims. First, we will retrospectively analyze a cohort of patients from 120 VA Hospitals to determine which patients with orthopedic surgical site infections (prosthetic joint infections) are at low risk for recurrent infections and thus do not need chronic antibiotic suppression. Second, Dr. Kimberly Dukes will perform site visits and qualitatively interview surgeons to determine what data the surgeons would need to de-implement chronic antibiotic suppression among these low risk patients and barriers and facilitators to de-implementation. Third, we will mathematically model different interventions to de-implement chronic antibiotic suppression in order to find the most effective and cost-effective intervention to implement.

Role: PI; Effort: 30%

  • CDC 1U54CK000448-01

Perencevich (PI)                                                             


Volume of Contamination and Nosocomial Infection Control (Epicenter)

I am leading a project to conduct 3 systematic literature reviews and meta-analyses regarding the effects of contact precautions to prevent the transmission of disease. The topics for these meta-analyses include the effectiveness of universal contact precautions, adverse events associated with standard contact precautions, and the positive impact of training for enhanced contact precautions for Ebola.

Role: Project Leader; Effort: 5%


Rubin (PI)                                                                                 


Combating Antimicrobial Resistance through Rapid Implementation of Available Guidelines and Evidence

The goal of this Quality Enhancement Research Initiative (QUERI) is to address the growing concern of antimicrobial resistance through strategies that enhance the improved use of antibiotics and prevention of HAI across VA patient care settings. This program also will target VA national priorities of building a high-performance healthcare network, improving employee engagement, and enhancing the U.S. National Action Plan for Combating Antibiotic-Resistant Bacteria. We will evaluate a hand hygiene surveillance program in VISN-23, evaluate the VA CRE Control Initiative and evaluate a stewardship initiative.

Role: Co-Investigator; Effort: 10%

Completed Research Support

  • VA HSR&D CDA 11-215

Schweizer (PI)                                                                 


Comparative Effectiveness of Strategies to Control S. aureus Infections

This study aimed to use meta-analyses, analysis of large VA datasets, and infectious disease modeling to compare the effectiveness of strategies to prevent and treat S. aureus infections.

Role: PI; Effort: 75%

  • AHRQ HHSA290200600021

Herwaldt (PI)                                                             


Optimizing Pre-Operative Antibiotic Prophylaxis for Cardiac and Orthopedic Procedures

This study aimed to determine the optimal bundled intervention to prevent S. aureus infections after cardiac and orthopedic surgery. Then to implement this bundle in 20 hospitals and evaluate the effectiveness.

Role: Co-Investigator

  • AHRQ HS022468-01

Herwaldt (PI)                                                             


Implementation and Effectiveness of a S. aureus Surgical Site Infection Prevention Bundle

This study aimed to understand the barriers to implementing a surgical site infection prevention bundle in orthopedic and cardiac surgery programs and to compare the effectiveness of different bundle components.

Role: Co-Investigator

  • VA HSR&D CRE 12-291

Perencevich (PI)                                                             


Checklist to Prevent MRSA Surgical Site Infections

The aim of the integrated 4-study VA HSR&D CREATE Program Project was to prevent MRSA infections in VA. This first project implemented a surgical site infection bundle in the orthopedic and cardiac surgical programs of 10 VA hospitals and evaluated it using a quasi-experimental design. We also performed qualitative interviews to identify barriers and facilitators to bundle implementation. Although grant ended on 3/31, we have received supplemental funds to continue this research for another year.

Role: Co-Investigator; Effort 20%

  • NIH HHSN272201300020I

Nair (PI)                                                                         


Effectiveness of Chronic Antibiotic Suppression for Treatment of Staphylococcus aureus Prosthetic Joint Infection

This retrospective cohort study, funded by the National Institutes of Health (NIH) Vaccine and Treatment Evaluation Units (VTEUs), analyzed VA data to evaluate the effectiveness of chronic antibiotics suppression to treat S. aureus prosthetic joint infection.

Role: Co-Investigator; Effort: 3%

  • CDC 200-2011-42039 SHEPheRD

Samore/Perencevich (PIs)                             


Assessment of the impact of healthcare-associated infections with resistant pathogens

The goal of this contract was to perform systematic literature reviews and meta-analyses of the burden and costs of the 8 most common healthcare-associated infections with resistant pathogens. Those data were then used to create infectious disease models to determine the impact of these infections in the U.S. both now and in the future.

Role: Co-Investigator

  • VA HSR&D IIR 12-103

Gupta (PI)                                                                           


Comparative Effectiveness and Cost of Surgical Prophylaxis Regimens

The goal of this study was to use national VA data to compare the effectiveness of vancomycin versus other antimicrobial surgical prophylaxis and to compare the costs of patient outcomes after surgery.

Role: Co-Investigator; Effort: 10%

  • FDA HHSF2232009100061

Chrischilles (PI)                                                         


Thromboembolic Events After Immunoglobulin Administration

The goal of this FDA Mini Sentinel contract was to evaluate health outcomes among individuals exposed to medical products. Specifically, this project aimed to evaluate whether IVIg administration is associated with thromboembolic events such as stroke and acute myocardial infarction.

Role: Co-Investigator; Effort 10%