for people ages 18 years and up (full criteria)
at Orange, California and other locations
study started
completion around
Principal Investigator
by Susan Huang, MD, MPH



The DECREASE SSI Trial (Decolonization to Reduce After-Surgery Events of Surgical Site Infection) is a two-arm multi-center individual placebo-controlled randomized (2,700 participants randomized 1:1) clinical trial to reduce post-discharge surgical site infection following open colon or small bowel surgery by comparing chlorhexidine bathing plus nasal mupirocin in the 30 days following discharge to soap without antiseptic properties (placebo) and placebo nasal ointment. This trial seeks to enhance the care of the 675,000 patients annually who undergo colon and small bowel surgery by finding simple and efficacious interventions to reduce SSI.


Surgical Site Infection, SSI, Infections, Communicable Diseases, Surgical Wound Infection, Chlorhexidine, Chlorhexidine gluconate, Local Anti-Infective Agents, Mupirocin, 4% Chlorhexidine Gluconate, 2% Mupirocin, Decolonization


You can join if…

Open to people ages 18 years and up

  • 18 years of age or older
  • Recent open (not solely laparoscopic) surgery involving an abdominal incision within the past 14 days. For cesarean section, recruitment restricted to BMI ≥ 40.
  • Able to communicate regularly by phone
  • Able to bathe, shower or have this task performed by a caregiver

You CAN'T join if...

  • Transfer to an acute care hospital
  • Discharged to receive end-of-life hospice measures
  • Discharged more than 14 days after surgery
  • Allergic to mupirocin and/or chlorhexidine
  • Active infection at enrollment*

    *Refers to

    1. Infections requiring systemic antibacterial agents, so viral illness (e.g., COVID, flu) is not an exclusion.
    2. Topical antibacterial agents do not count toward exclusion (e.g., topical products for acne)
    3. Prophylactic antibacterial agents do not count toward exclusion
  • Surgical incision not closed at discharge


  • University of California, Irvine Medical Center accepting new patients
    Orange California 92868 United States
  • University of California, San Francisco Medical Center accepting new patients
    San Francisco California 94143 United States
  • University of California, Davis Medical Center accepting new patients
    Sacramento California 95817 United States

Lead Scientist at UC Irvine

  • Susan Huang, MD, MPH
    Professor, Medicine, School of Medicine. Authored (or co-authored) 199 research publications


accepting new patients
Start Date
Completion Date
University of California, Irvine
Phase 4 Surgical Wound Infection Research Study
Study Type
Expecting 2700 study participants
Last Updated