2 Introduction

Healthcare-associated infections, commonly referred to as HAIs, are infections that patients acquire during treatment for conditions within a healthcare setting, such as a hospital, ambulatory surgical center, nursing home, or outpatient care center. These are one of the major types of complications or adverse events that can occur when receiving medical treatment in a healthcare facility. These infections can be relatively minor and easily treatable (such as a minor skin infection) or can be devastating to both patients and their families due to lost time and wages, the need for additional treatment, additional days in the hospital, and increased medical costs. This report addresses a subset of HAIs that were reported from hospitals to NHSN. This report quantifies the number of HAIs reported to NHSN by hospitals and provides a measure of each hospital’s success in reporting fewer HAIs than a statistical model predicted based on the hospital’s characteristics, number of patients at risk of getting the infection and the rate of HAIs that were reported in 2015.

In 2007, Pennsylvania was one of the first states to pass HAI legislation assigning specific responsibilities to the Department, the Pennsylvania Safety Authority (PSA) and PHC4 to monitor and reduce HAIs in healthcare facilities. The Department tracks HAIs, distributes quarterly validation reports to hospitals regarding HAIs reported to NHSN, publishes Pennsylvania NHSN HAI data, provides guidance and technical support to healthcare facilities regarding NHSN, and reviews infection control plans for hospitals, long-term care facilities, and ambulatory surgical facilities. Recently, the Department expanded its role through work with CDC. These expanded roles include:

  • Validating HAIs reported to NHSN;
  • Making recommendations for practice changes to fill gaps in implementation of national guidelines;
  • Assisting inpatient healthcare facilities to prevent and manage outbreaks that involve multidrug-resistant organisms;
  • Assisting healthcare facilities prevent and mitigate the effects of infection control breaches;
  • Training the healthcare workforce in fundamental infection prevention and control principles and germ theory; and
  • Assisting providers and facilities with implementing better antimicrobial stewardship programs.

Healthcare-associated infections reported to NHSN continue to represent an important patient safety concern. In 2015, CDC reported there were an estimated 687,000 HAIs in U.S. acute care hospitals (ACHs) and about 72,000 deaths associated with HAIs.1 In a 2009 report published by CDC, it was estimated that the direct costs of HAIs to US hospitals was more than 28 billion dollars, of which 70% was estimated as preventable.4 In 2009, HHS issued a five-year National Action Plan to Prevent Health Care-Associated Infections5 in a variety of healthcare settings. In 2016, it was updated to establish new reduction goals and defined a new five-year period for NHSN HAIs (2015-2020). Health and Human Services is currently working to update this plan with new indicator targets, data, and intervention efforts, as well as include a review of the impact of the COVID-19 public health emergency on HAIs.6 This 2020 Pennsylvanian HAI report focuses on the five types of NHSN HAIs benchmarked in Pennsylvania and targeted by HHS for reduction in the 2016 HAI National Action Plan. These infections include:

  1. Central line-associated bloodstream infection (CLABSI);
  2. Catheter-associated urinary tract infection (CAUTI);
  3. Surgical site infection (SSI) [for seven procedure types];
  4. Laboratory-identified bloodstream infection (LabID) events caused by MRSA; and
  5. Laboratory-identified infection events caused by Clostridioides difficile (CDI).

This report serves as a resource for healthcare providers and for the public who seek information about HAI prevention and reduction progress. Hospitals can download data included in this report to assess their HAI reduction strategies and progress. Healthcare consumers in Pennsylvania can use this report to have an awareness of HAI risk at the hospital they may choose.

This is the fifth report to use an online format which was produced using R statistical software (version 4.2.2).7 This report displays the number of HAIs reported by each hospital between January 1, 2020, and December 31, 2020. The number of infections alone cannot be used to determine how well a facility ranks in their efforts to prevent infections. Because factors intrinsic to the hospital and patient contribute to the development of HAIs, a metric which adjusts for some of those factors has also been included in this report. This metric should also be evaluated to determine how well a facility ranks in the efforts to prevent infections. That metric is called the SIR.

2.1 Catheter-Associated Urinary Tract Infection (CAUTI)

A urinary tract infection (UTI) is an infection involving any part of the urinary system, including the urethra, bladder, ureter, and kidney. Among UTIs acquired during a hospitalization, approximately 75% are associated with an indwelling urinary catheter, a tube inserted into the bladder and left in place to drain urine.8 These UTIs may be classified as a CAUTI, if the urinary catheter that was inserted into the urinary bladder had been in place for more than two calendar days and certain other criteria are met.9 Between 15% and 25% of all hospitalized patients receive urinary catheters during their hospital stay; many catheters are not needed or stay in place longer than needed.8

The most effective way to reduce CAUTIs is to reduce unnecessary urinary catheter placement by establishing clear indications for use and minimizing the length of time it remains in place by removing it as soon as the medical necessity no longer exists. Each day that a patient has a catheter in place the risk for developing a CAUTI increases by 3% to 7%.10,11 The 2016 attributable cost to Medicare inpatients with a CAUTI was dependent on the patient’s location in the hospital (as well as other factors), such as $1,764 for patients in a non-intensive care unit (ICU) and $10,197 for the patients in the ICU.12 The Centers for Medicare and Medicaid Services (CMS) no longer reimburses hospitals for additional costs generated by CAUTIs.

Many resources are available for healthcare providers that outline strategies and guidelines for prevention of CAUTIs including those published by the Society for Healthcare Epidemiology of America (SHEA)10 and the Association for Professionals in Infection Control and Epidemiology (APIC). Strategies to prevent CAUTIs are discussed in CDC’s Healthcare Infection Control Practices Advisory Committee (CDC/HICPAC) document, Guideline for Prevention of Catheter-Associated Urinary Tract Infections.13

2.2 Central Line-Associated Bloodstream Infection (CLABSI)

A central line is a device used to administer fluids, medications, blood, and nutrition, to collect blood needed for laboratory testing or to measure a patient’s status. Unlike short peripheral intravenous catheters, these catheters are inserted to access major vessels located near the heart and are placed via a large vein in the neck, chest, groin, or through veins in the arms. A central line can stay in place for weeks to months.14

Bacteria or other organisms can sometimes enter a patient’s bloodstream through a central line. If a bloodstream infection is detected, this may be a CLABSI if all NHSN criteria are met and a different NHSN infection is not identified elsewhere in the body (e.g., the lungs or skin).

Central line-associated bloodstream infections continue to be a serious patient safety issue as well as an economic burden to healthcare facilities even though United States CLABSI rates decreased 46% from 2008-2013.15 An estimated 30,100 CLABSIs still occur in United States hospitals each year. Each CLABSI is estimated to cost approximately $70,696 (2012 dollars).16 The CMS no longer reimburses hospitals for additional costs generated by CLABSIs.17 In 2011, research indicated that between 65% and 70% of CLABSIs were preventable by implementing evidence-based strategies and CLABSIs were associated with the highest number of preventable deaths.18 A review of articles published between 2005 and 2016 revealed that the pooled incidence rate ratio associated with multifaceted CLABSI interventions was 0.459 (95% CI: 0.381, 0.554).3 This means that 45.9% of CLABSIs could be prevented through use of multifaceted interventions.

In 2022, the SHEA/IDSA/APIC Compendium of Strategies to Prevent Healthcare-Associated Infections in Acute Care Hospitals, also known as the Compendium, published updated recommendations for preventing CLABSIs.19 Other evidence-based guidelines include APIC’s 2015 Implementation Guide to Preventing Central Line-Associated Bloodstream Infections14 and the CDC/HICPAC Guidelines for the Prevention of Intravascular Catheter-Related Infections, 2011.20

2.3 Surgical Site infections (SSIs)

Surgical site infections are attributed to a specific surgical procedure and vary in complexity and infection depth. The infection depth ranges from (1) superficial incisional infections to (2) those located deep into muscle, to (3) those penetrating deeper than the fascial/muscle layer (organ/space).9

Patients with an SSI have a two to 11 times higher risk of death compared with operative patients without an SSI. The number of SSIs in the United States has significantly decreased since 2011 and account for 20% to 22% of all HAIs.1 In 2002, Klevens et al.21 estimated there were 274,098 SSIs among hospitalized adults and children in the United States. By 2011, the estimated SSIs decreased to 157,50022 and, by 2015, the number further decreased to 110,800.1 Between 2006 and 2008, the SSI rate from all procedure types in 39 states was 1.9%.23 Similar data from 2010-2012 determined the SSI rate to be 0.82%24 or 0.97%.22 By 2015, the national SSI rate dropped to 0.56%.1

Surgical site infections are associated with human and financial costs related to lost work time, increased days in the hospital (on average an added 9.7 days),25 added treatment costs including return to the operating room, emergency department visits, and readmissions to the hospitals. Per CDC’s 2017 Guideline for the Prevention of Surgical Site Infection, the cost of an SSI ranges from $10,443 to $25,546 per infection, and costs can exceed $90,000 when the SSI involves a prosthetic joint implant or antibiotic-resistant organism.26

A review of articles published between 2005 and 2016 revealed that the pooled incidence rate ratio associated with multifaceted SSI interventions was 0.461 which reached statistical significance (95% CI: (0.389, 0.546).3 This means that 46.1% of SSIs could be prevented if multifaceted interventions were implemented by hospitals. Facility SSI reduction efforts as recommended in APIC’s 2015 Implementation Guide: (Infection Preventionist’s Guide to the OR)27 should include resources so that hospital infection prevention and control programs can support the perioperative team to implement the most current and evidence-based surgical infection prevention and control strategies, as well as tracking and communicating SSI rates to the perioperative team. Guidelines and evidence-based recommendations to prevent SSIs include CDC’s updated Guideline for the Prevention of Surgical Site Infection,26 the American College of Surgeons and Surgical Infection Society: Surgical Site Infection Guidelines, 2016 Update,25 and the Compendium’s 2022 Update to Strategies to Prevent Surgical Site Infections in Acute-Care Hospitals.28 It is recommended that facilities incorporate evidence-based strategies as well as multifaceted interventions into a comprehensive surgical quality improvement program to reduce SSIs.

2.4 Clostridioides difficile infection (CDI) in the stool

Clostridioides difficile is an anaerobic, Gram-positive, spore-forming bacillus (bacteria) that can produce two exotoxins, toxin A and toxin B. It was considered nonpathogenic until 1978 when it was identified as the primary cause of pseudomembranous colitis following antibiotic exposure.29 C. difficile infection is the leading cause of antibiotic-associated diarrhea in the United States,1 has become the most commonly identified cause of HAIs in United States adults, is a major health threat to hospitalized patients, and, in recent years, has become established as a community acquired pathogen. Prior to May 2019 Clostridioides difficile was called Clostridium difficile.

The development of CDI most commonly requires two components: exposure to antibiotics and acquisition of C. difficile from the ingestion of spores (fecal-oral transmission). Antibiotics suppress or disrupt the normal bowel microbiota (bacteria) that allow for C. difficile to flourish when spores are ingested. In the healthcare setting, exposure to C. difficile spores may occur via the contaminated hands of healthcare personnel or contact with contaminated environmental surfaces or equipment. A significant risk factor for CDI is occupying a room where a prior occupant had CDI.31 Exposure to antibiotics is considered a modifiable risk factor; however, in 2015 49.5% of hospitalized patients received one or more antimicrobial medications.32 Other risk factors for CDI include advanced age, long hospitalization stays, and severe underlying illness.

A study funded by the CDC to assess the burden of C. difficile in the United States in 2017 estimated that C. difficile was responsible for 462,100 infections and associated with approximately 20,500 in-hospital deaths.33 Fifty-one percent (N=235,700) of the infections were classified as healthcare-associated, meaning that the positive stool was collected >3 days after hospital admission or from a resident of a long-term care facility. Thirty-seven percent (N = 87,000) of these HAIs were estimated to occur during a hospital visit (hospital onset). Twenty-four percent (N = 56,600) of these HAIs were classified as occurring in nursing homes (nursing home onset) and 39% were classified as having onset dates in the community after the patient had recently visited a healthcare facility. The remaining 226,400 CDI cases were classified as community onset. This was 49% of all cases. The study estimated that 16,200 in-hospital deaths occurred among those classified as hospital onset cases.

United States hospital discharge data indicate that the number of hospital discharges with a diagnosis of CDI plateaued at historic highs between 2011 and 2013.34 In 2004 and 2014, respectively, 1.9 million and 600,000 patients discharged from United States hospitals had a C. difficile infection listed as their discharge and principal diagnosis. C. difficile-associated fatality decreased from 3.6% in 2004 to 1.6% in 2014, meanwhile the mean hospital charges increased from 2004 ($24,535) to 2014 ($35,898).35 In a Canadian study, patients with CDI had an increased hospital stay of six days.36 Approximately 14% to 26% of individuals who recover from CDI experience a recurrence. In the patients who experienced a single recurrence, the risk of additional recurrences may be as high as 65%.37

SHEA and the Infectious Diseases Society of America (IDSA) updated their clinical practice guidelines for C. difficile in 2017.34 In 2013, APIC developed their Guide to Preventing Clostridium difficile Infections.38

2.5 Methicillin-resistant Staphylococcus aureus (MRSA) found in the blood

Staphylococcus aureus is a bacterium often called “staph” that is commonly found on the skin and does not typically cause an infection. However, when staph enters the bloodstream, it can cause a serious infection and even death. These infections can resolve with proper medical treatment, but some staph infections can become resistant to antibiotics, like methicillin. These types of staph infections are named methicillin-resistant Staphylococcus aureus (MRSA). About 2% of people carry MRSA in their nose or skin.39 MRSA can be spread by someone who is infected or colonized with MRSA to another person through direct contact or contact with contaminated equipment or shared personal items.

Outbreaks of MRSA have occurred in daycare centers, on sports teams, in group homes, and in healthcare facilities. In hospitals, MRSA can be passed from one person to another through contaminated hands of healthcare workers or visitors and on surfaces contaminated with MRSA, such as bedrails or medical equipment. Anyone can get MRSA, but those living in or involved with activities that take place in crowded settings (e.g., athletes, military barracks), as well as hospitalized patients who have undergone surgery, have received broad spectrum antimicrobials, have had devices inserted into their bodies, or have been admitted into a room in which the previous occupant was colonized or infected with MRSA are at an increased risk for acquisition of MRSA.40 Per the CDC, persons who inject drugs are 16 times more likely to develop a serious staph infection41 and of all patients treated in United States hospitals, 5% carry MRSA in their nose or on their skin, which is known as being colonized.39

A 2019 study published in the Morbidity and Mortality Weekly Report reported that MRSA bloodstream infections in healthcare settings decreased nationally by approximately 17% each year from 2005 until 2013.42 Since 2013, the rate in which MRSA bloodstream infections declined has slowed. Recent NHSN data show that the lowest national MRSA bacteremia standardized infection ratios (SIR = 0.82) were reported in 2019.43 This is much higher than the 2020 HHS Healthy People goal of 0.50.

Methicillin-resistant Staphylococcus aureus infection prevention and control remains a priority for the CDC because MRSA is estimated to cause more than 70,000 severe infections and 9,000 deaths per year in the U.S.44 Based on the current evidence, CDC continues to recommend the use of contact precautions for MRSA-colonized or infected patients45 as does SHEA.46 Healthcare facilities and infection preventionists are encouraged to monitor MRSA community and admission prevalence rates and healthcare data to determine which prevention strategies to implement, as well as to evaluate the effectiveness of their infection prevention and control practices.