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Epidemiology of surgical site infection in adults

Deverick J Anderson, MD, MPH
Daniel J Sexton, MD
Section Editor
Anthony Harris, MD, MPH
Deputy Editor
Elinor L Baron, MD, DTMH


Surgical wound infections are a common cause of nosocomial infection. The United States Centers for Disease Control and Prevention (CDC) has developed criteria that define surgical site infection (SSI) as infection related to an operative procedure that occurs at or near the surgical incision within 30 days of the procedure or within 90 days if prosthetic material is implanted at surgery [1]. SSIs are often localized to the incision site but can also extend into deeper adjacent structures.

SSIs are the most common nosocomial infection, accounting for 38 percent of nosocomial infections. However, the overall risk of SSI is low; it is estimated that SSIs develop in 2 to 5 percent of the more than 30 million patients undergoing surgical procedures each year (ie, 1 in 24 patients who undergo inpatient surgery in the United States has a postoperative SSI) [1-3].

SSI rates in ambulatory surgical settings are relatively low; one study noted overall rates at 14 and 30 days of 3.1 and 4.8 per 1000 procedures [4].

The epidemiology and risk factors for SSI will be reviewed here. Antimicrobial prophylaxis and adjunctive measures for prevention of surgical site infection are discussed separately. (See "Antimicrobial prophylaxis for prevention of surgical site infection in adults" and "Overview of control measures for prevention of surgical site infection in adults".)


Surgical site infections (SSIs) are associated with substantial morbidity and mortality, prolonged hospital stay, and increased cost. [5-7]. Among patients with SSI who die in the postoperative period, death is directly related to SSI in over 75 percent of cases. In one paired case-control study of SSI following orthopedic procedures, the occurrence of SSI accounted for a median increase in hospital stay of 14 days, an increase in the rate of rehospitalization of twofold, and increased total costs of more than 300 percent [8].

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Literature review current through: Sep 2017. | This topic last updated: Jul 07, 2017.
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  1. Horan TC, Gaynes RP, Martone WJ, et al. CDC definitions of nosocomial surgical site infections, 1992: a modification of CDC definitions of surgical wound infections. Infect Control Hosp Epidemiol 1992; 13:606.
  2. Consensus paper on the surveillance of surgical wound infections. The Society for Hospital Epidemiology of America; The Association for Practitioners in Infection Control; The Centers for Disease Control; The Surgical Infection Society. Infect Control Hosp Epidemiol 1992; 13:599.
  3. Lewis SS, Moehring RW, Chen LF, et al. Assessing the relative burden of hospital-acquired infections in a network of community hospitals. Infect Control Hosp Epidemiol 2013; 34:1229.
  4. Owens PL, Barrett ML, Raetzman S, et al. Surgical site infections following ambulatory surgery procedures. JAMA 2014; 311:709.
  5. Boyce JM, Potter-Bynoe G, Dziobek L. Hospital reimbursement patterns among patients with surgical wound infections following open heart surgery. Infect Control Hosp Epidemiol 1990; 11:89.
  6. Poulsen KB, Bremmelgaard A, Sørensen AI, et al. Estimated costs of postoperative wound infections. A case-control study of marginal hospital and social security costs. Epidemiol Infect 1994; 113:283.
  7. Vegas AA, Jodra VM, García ML. Nosocomial infection in surgery wards: a controlled study of increased duration of hospital stays and direct cost of hospitalization. Eur J Epidemiol 1993; 9:504.
  8. Whitehouse JD, Friedman ND, Kirkland KB, et al. The impact of surgical-site infections following orthopedic surgery at a community hospital and a university hospital: adverse quality of life, excess length of stay, and extra cost. Infect Control Hosp Epidemiol 2002; 23:183.
  9. Perencevich EN, Sands KE, Cosgrove SE, et al. Health and economic impact of surgical site infections diagnosed after hospital discharge. Emerg Infect Dis 2003; 9:196.
  10. Anderson DJ, Kaye KS, Chen LF, et al. Clinical and financial outcomes due to methicillin resistant Staphylococcus aureus surgical site infection: a multi-center matched outcomes study. PLoS One 2009; 4:e8305.
  11. Hughes JM, Culver DH, White JW, et al. Nosocomial infection surveillance, 1980-1982. MMWR CDC Surveill Summ 1983; 32:1SS.
  12. Guinan JL, McGuckin M, Nowell PC. Management of health-care--associated infections in the oncology patient. Oncology (Williston Park) 2003; 17:415.
  13. CDC NNIS System. National Nosocomial Infections Surveillance (NNIS) report, data summary from October 1986- April 1998, Issued June 1998.
  14. Bratzler DW, Dellinger EP, Olsen KM, et al. Clinical practice guidelines for antimicrobial prophylaxis in surgery. Surg Infect (Larchmt) 2013; 14:73.
  15. Anderson DJ, Podgorny K, Berríos-Torres SI, et al. Strategies to prevent surgical site infections in acute care hospitals: 2014 update. Infect Control Hosp Epidemiol 2014; 35:605.
  16. Anthony CA, Peterson RA, Polgreen LA, et al. The Seasonal Variability in Surgical Site Infections and the Association With Warmer Weather: A Population-Based Investigation. Infect Control Hosp Epidemiol 2017; 38:809.
  17. Delgado-Rodríguez M, Gómez-Ortega A, Sillero-Arenas M, Llorca J. Epidemiology of surgical-site infections diagnosed after hospital discharge: a prospective cohort study. Infect Control Hosp Epidemiol 2001; 22:24.
  18. Kluytmans J. Surgical infections including burns. In: Prevention and Control of Nosocomial Infections, Wenzel (Ed), Williams and Wilkins, Baltimore 1997. p.841.
  19. Kaye KS, Schmit K, Pieper C, et al. The effect of increasing age on the risk of surgical site infection. J Infect Dis 2005; 191:1056.
  20. Haley RW, Culver DH, Morgan WM, et al. Identifying patients at high risk of surgical wound infection. A simple multivariate index of patient susceptibility and wound contamination. Am J Epidemiol 1985; 121:206.
  21. Culver DH, Horan TC, Gaynes RP, et al. Surgical wound infection rates by wound class, operative procedure, and patient risk index. National Nosocomial Infections Surveillance System. Am J Med 1991; 91:152S.
  22. Mu Y, Edwards JR, Horan TC, et al. Improving risk-adjusted measures of surgical site infection for the national healthcare safety network. Infect Control Hosp Epidemiol 2011; 32:970.
  23. Henderson WG, Daley J. Design and statistical methodology of the National Surgical Quality Improvement Program: why is it what it is? Am J Surg 2009; 198:S19.
  24. Shahian DM, O'Brien SM, Filardo G, et al. The Society of Thoracic Surgeons 2008 cardiac surgery risk models: part 1--coronary artery bypass grafting surgery. Ann Thorac Surg 2009; 88:S2.