Do Antibiotic Stewardship Programs Improve Patient Care?

Introduction

Antibiotics are revolutionary medicines that have fundamentally changed healthcare, transforming previously deadly infections into readily treatable conditions and enabling advanced medical procedures such as chemotherapy and organ transplantation. The rapid administration of antibiotics to treat infections is crucial for reducing illness and saving lives, particularly in severe cases like sepsis. However, studies reveal that approximately 30% of all antibiotics prescribed in acute care hospitals across the United States are either unnecessary or not optimally chosen.

Like all medications, antibiotics carry the risk of significant side effects, affecting about 20% of hospitalized patients who receive them. Unnecessary antibiotic exposure puts patients at risk of these adverse events without offering any therapeutic benefit. Furthermore, the inappropriate use of antibiotics is a major driver of antibiotic resistance, a critical public health threat. Misuse of these drugs can negatively impact the health of individuals beyond those directly treated, contributing to the spread of resistant bacteria and Clostridioides difficile (C. difficile) infections.

Optimizing antibiotic use is essential for effectively treating infections, safeguarding patients from harms associated with unnecessary antibiotic use, and combating the growing challenge of antibiotic resistance. Antibiotic Stewardship Programs (ASPs) are designed to assist healthcare providers in enhancing patient outcomes and minimizing harm by improving how antibiotics are prescribed. Hospital-based ASPs have demonstrated the ability to improve infection cure rates while simultaneously reducing:

Treatment failures
C. difficile infections
Adverse drug effects
Antibiotic resistance
Hospital costs and lengths of stay

Recognizing the critical need for improved antibiotic use, the Centers for Disease Control and Prevention (CDC) issued a call in 2014 for all hospitals in the United States to implement antibiotic stewardship programs. To support this initiative, the CDC released the Core Elements of Hospital Antibiotic Stewardship Programs (Core Elements), a framework outlining essential structural and procedural components for successful stewardship programs.

In 2015, the United States National Action Plan for Combating Antibiotic-Resistant Bacteria established a national goal to implement these Core Elements in all hospitals receiving federal funding.

Core Elements Implementation and the Evolution of Antibiotic Stewardship

To further facilitate the adoption of the Core Elements, the CDC has undertaken several initiatives, recognizing the evolving landscape of antibiotic stewardship and its crucial role in patient care.

Antibiotic Stewardship and Sepsis Management

Misconceptions have sometimes arisen suggesting that antibiotic stewardship might impede efforts to improve sepsis management in hospitals. However, rather than being a hindrance, antibiotic stewardship programs are integral to optimizing antibiotic use, which ultimately leads to improved patient outcomes, even in severe conditions like sepsis. Effective ASPs ensure timely and appropriate antibiotic therapy while preventing overuse, thus supporting better care for sepsis patients.

Across the nation, healthcare facilities are increasingly using the Core Elements as a guide for their antibiotic stewardship efforts within hospital settings. These Core Elements serve as the basis for antibiotic stewardship accreditation standards set by The Joint Commission and DNV-GL, highlighting their importance in ensuring quality patient care. Furthermore, the 2019 hospital Conditions of Participation from the Centers for Medicare and Medicaid Services (CMS) established a federal regulation mandating hospital antibiotic stewardship programs, reinforcing the Core Elements as a national standard. Remarkable progress has been made in the United States, with 85% of acute care hospitals reporting implementation of all seven Core Elements in 2018, a significant increase from just 41% in 2014.

The field of antibiotic stewardship has advanced significantly since 2014, marked by substantial research and the publication of an implementation guideline by the Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America in 2016. This evolution underscores the growing recognition of the importance of infection control programs, specifically ASPs, in enhancing patient care.

Core Elements for Hospital Antibiotic Stewardship Programs: 2019 Update

Recognizing the advancements and practical experiences gained, the CDC updated the Core Elements for Hospital Antibiotic Stewardship Programs in 2019. This updated document incorporates new evidence and insights gathered from five years of implementation, providing an enhanced framework for hospitals. The Core Elements are designed to be adaptable and applicable to all hospitals, regardless of size, with specific guidance for small and critical access hospitals detailed in Implementation of Antibiotic Stewardship Core Elements at Small and Critical Access Hospitals.

It is important to note that there is no one-size-fits-all blueprint for optimizing antibiotic prescribing in hospitals. The complexity of medical decisions related to antibiotic use and the diversity in hospital sizes and types of care necessitate a flexible approach to implementing antibiotic stewardship programs. The Core Elements serve as an adaptable framework that hospitals can utilize to guide their efforts in improving antibiotic prescribing practices, ultimately leading to improved patient care. An accompanying assessment tool is available to help hospitals identify areas for improvement and tailor their stewardship programs effectively.

Summary of Key Updates in the 2019 Core Elements

The 2019 update of the hospital Core Elements reflects lessons learned over five years and incorporates new evidence in the field of antibiotic stewardship. These updates are designed to further improve the effectiveness of ASPs and their impact on patient care. Major updates include refinements and expansions within each of the Core Elements:

Hospital Leadership Commitment

Securing dedicated human, financial, and information technology resources is paramount.

The 2019 update provides expanded examples of hospital leadership commitment, categorized into “priority” and “other” examples.
Priority examples emphasize the necessity of dedicated time and resources for ASP leadership to operate effectively. It also highlights the importance of regularly scheduled opportunities for program leaders to report stewardship activities, resource utilization, and outcomes to senior executives and the hospital board. This ensures that ASPs are integrated into the hospital’s broader patient care and quality improvement initiatives.

Accountability

Designating a leader or co-leaders, such as a physician and pharmacist, who are responsible for program management and outcomes is crucial.

The 2019 update emphasizes the effectiveness of physician and pharmacist co-leadership, a model reported by 59% of hospitals in the 2019 NHSN Annual Hospital Survey. This collaborative leadership model leverages the expertise of both professions to enhance program effectiveness and ensure comprehensive oversight of antibiotic stewardship efforts.

Pharmacy Expertise (formerly “Drug Expertise”)

Appointing a pharmacist, ideally as a co-leader, to spearhead implementation efforts aimed at improving antibiotic use is essential.

This Core Element was renamed from “Drug Expertise” to “Pharmacy Expertise” to better reflect the critical role of pharmacy engagement in leading the practical implementation of strategies to enhance antibiotic use. Pharmacists are central to medication management and play a vital role in optimizing antibiotic therapy.

Action

Implementing specific interventions, such as prospective audit and feedback or preauthorization, to improve antibiotic utilization is the core of the program.

The 2019 update provides additional examples of interventions, categorized as “priority” and “other”. The “other” interventions are further classified as infection-based, provider-based, pharmacy-based, microbiology-based, and nursing-based, offering a more detailed and comprehensive set of strategies.
Priority interventions include prospective audit and feedback, preauthorization, and the development of facility-specific treatment recommendations. Evidence strongly supports prospective audit and feedback and preauthorization as effective in improving antibiotic use and are recommended in guidelines as “core components of any stewardship program”. Facility-specific treatment guidelines are crucial for enhancing the effectiveness of these interventions.
The 2019 update highlights the importance of focusing actions on the most common indications for hospital antibiotic use: lower respiratory tract infections (e.g., community-acquired pneumonia), urinary tract infections, and skin and soft tissue infections, as these areas offer significant opportunities for improvement.
The antibiotic timeout is reframed as a valuable supplemental intervention, but it is clarified that it should not replace prospective audit and feedback, emphasizing the latter’s more comprehensive and expert-driven approach.
A new category of nursing-based actions was added to acknowledge the significant role nurses play in hospital antibiotic stewardship efforts, recognizing their frontline involvement in patient care and medication management.

Tracking

Monitoring antibiotic prescribing practices, the impact of interventions, and key outcomes such as C. difficile infection rates and resistance patterns is essential for program evaluation and improvement.

The update emphasizes the importance of electronic submission of antibiotic use data to the National Healthcare Safety Network (NHSN) Antimicrobial Use (AU) Option for monitoring and benchmarking inpatient antibiotic use. This national database provides valuable comparative data for hospitals to assess their performance and identify areas for improvement.
Antibiotic stewardship process measures were expanded and categorized into “priority” and “other”, providing a more structured approach to evaluating program activities.
Priority process measures focus on assessing the impact of key interventions, including prospective audit and feedback, preauthorization, and adherence to facility-specific treatment recommendations, ensuring that the most impactful strategies are closely monitored.

Reporting

Regularly disseminating information on antibiotic use and resistance trends to prescribers, pharmacists, nurses, and hospital leadership is vital for ongoing education and program support.

The 2019 update highlights the effectiveness of provider-level data reporting, acknowledging that while not extensively studied in hospital antibiotic use, it is likely to be a powerful tool for influencing prescribing behavior by providing clinicians with direct feedback on their practices compared to peers.

Education

Providing education to prescribers, pharmacists, and nurses about adverse reactions from antibiotics, antibiotic resistance, and optimal prescribing practices is a continuous need.

The 2019 update emphasizes that case-based education, delivered through prospective audit and feedback and preauthorization, is a particularly effective method for educating on antibiotic use. This approach is especially impactful when education is provided in person, such as through “handshake stewardship,” allowing for immediate and personalized feedback.
The update also suggests engaging nurses in patient education efforts, recognizing their crucial role in communicating with patients and reinforcing appropriate antibiotic use behaviors.

Hospital Leadership Commitment: The Foundation of Successful ASPs

Support from senior hospital leadership, particularly the chief medical officer, chief nursing officer, and director of pharmacy, is absolutely critical for the success of antibiotic stewardship programs. A frequently cited barrier to effective stewardship programs is the lack of necessary resources. Hospital leadership plays a pivotal role in securing the resources needed for the program to achieve its objectives and ultimately improve patient care.

Figure 1: Depiction of hospital leadership actively supporting an antibiotic stewardship program, emphasizing resource allocation and commitment.

Interestingly, while the primary goal of stewardship programs is to enhance patient care, numerous studies have demonstrated that these programs are often cost-neutral or even cost-saving. Savings are realized through reductions in antibiotic expenditures and indirect costs associated with complications like C. difficile infections and prolonged hospital stays.

Priority Examples of Leadership Commitment

Allocating dedicated time for stewardship program leader(s) to manage the program and conduct daily stewardship interventions. This ensures that leadership can actively engage in program activities and drive improvements in antibiotic use.
Providing adequate resources, including staffing, to operate the program effectively. Staffing recommendations for hospital antibiotic stewardship programs are available from the Veteran’s Administration and various publications, offering guidance on appropriate resource allocation.
Conducting regular meetings with stewardship program leaders to assess resource needs and ensure alignment with the hospital’s goals for improving antibiotic use. These meetings facilitate ongoing communication and adaptive resource management.
Appointing a senior executive leader to serve as a point of contact or “champion” for the stewardship program. This executive champion helps ensure the program has the necessary organizational support and advocacy to succeed.
Regularly reporting stewardship activities and outcomes (including success stories) to senior leadership and the hospital board. This reporting keeps leadership informed and reinforces the value and impact of the ASP on hospital-wide quality and patient safety metrics.

Other Examples of Leadership Commitment

Integrating antibiotic stewardship activities into broader quality improvement and patient safety initiatives, such as sepsis management and diagnostic stewardship. This integration ensures that ASPs are not siloed but are part of a comprehensive approach to patient care enhancement.
Establishing clear expectations for program leaders regarding responsibilities and desired outcomes. Clear expectations ensure accountability and focus program efforts effectively.
Issuing formal statements of support for efforts to improve and monitor antibiotic use. Public statements from hospital leadership reinforce the importance of antibiotic stewardship and create a supportive organizational culture.
Incorporating stewardship-related duties into job descriptions and annual performance reviews for program leads and key support staff. This formal integration of stewardship responsibilities ensures accountability and recognition for staff involved in these efforts.
Supporting training and education for program leaders (e.g., attendance at stewardship training courses and meetings) and hospital staff. Investing in training ensures that personnel have the knowledge and skills to effectively implement and participate in stewardship activities.
Supporting enrollment in and reporting to the National Healthcare Safety Network (NHSN) Antimicrobial Use and Resistance (AUR) Module, including providing necessary information technology support. Participation in national surveillance systems allows for benchmarking and continuous quality improvement.
Supporting participation in local, state, and national antibiotic stewardship quality improvement collaboratives. Collaborative participation facilitates shared learning, resource sharing, and collective advancement of stewardship practices.
Ensuring that staff from key support departments have sufficient time to contribute to stewardship activities. Recognizing that stewardship is a multidisciplinary effort, leadership must ensure that staff from various departments have allocated time to contribute effectively.

Key Support Departments and Personnel

Hospital leadership can facilitate stewardship program success by ensuring that other groups and departments within the hospital are aware of and actively collaborate with the stewardship program. Strong support from the following groups significantly enhances the effectiveness of ASPs:

Clinicians: Full engagement and support from all clinicians are vital for improving antibiotic use. Hospitalists are particularly important to engage, as they are often among the largest prescribers of antibiotics in hospitals and typically have experience with quality improvement initiatives.

Department or program heads: Support from clinical department heads, as well as the director of pharmacy, is crucial for embedding stewardship activities into daily clinical workflows.

Pharmacy and therapeutics committee: This committee plays a key role in developing and implementing policies that promote improved antibiotic use, such as incorporating stewardship principles into order sets and clinical pathways. Some hospitals establish a multidisciplinary stewardship subcommittee within the Pharmacy and Therapeutics Committee to specifically focus on these issues.

Infection preventionists and hospital epidemiologists: These professionals can assist with staff education and with analyzing and reporting data on antibiotic resistance and C. difficile infection trends. They can also support reporting to the NHSN AUR Module, ensuring accurate and timely data submission.

Quality improvement, patient safety, and regulatory staff: These teams can advocate for adequate resources for ASPs and integrate stewardship interventions into broader quality improvement efforts, particularly in areas like sepsis management. They can also support the implementation and evaluation of stewardship outcomes.

Microbiology laboratory staff:

Guide the appropriate utilization of diagnostic tests and the interpretation of results as part of “diagnostic stewardship.”
Help optimize empiric antibiotic prescribing by creating and interpreting facility-specific cumulative antibiotic resistance reports or antibiograms. Collaborative efforts between laboratory and stewardship personnel can ensure that lab data is presented in a format that effectively supports optimal antibiotic use and aligns with hospital guidelines.
Guide discussions on the potential implementation of rapid diagnostic tests and updated antibacterial susceptibility test interpretive criteria (e.g., antibiotic breakpoints) that may impact antibiotic use. Joint efforts between microbiology labs and stewardship programs are essential to optimize the use of these advanced diagnostics and the communication of results to clinicians.
Collaborate with stewardship program personnel to develop guidance for clinicians when changes in laboratory testing practices might affect clinical decision-making, ensuring smooth transitions and consistent patient care.
In hospitals where microbiology services are contracted externally, leadership should ensure that necessary information is accessible to inform and support stewardship efforts.

Information technology staff: IT support is critical for integrating stewardship protocols into existing clinical workflows. Examples include:

Embedding relevant information and protocols at the point of care, such as within electronic order sets and providing easy access to facility-specific guidelines.
Implementing clinical decision support systems for antibiotic use and creating prompts for action to review antibiotic prescriptions in key clinical situations.
Facilitating and maintaining NHSN AUR reporting, ensuring seamless data submission and system maintenance.

Nurses: There is growing recognition of the vital role nurses play in hospital stewardship efforts. Nurses can significantly contribute to:

Optimizing diagnostic testing, or diagnostic stewardship. For example, nurses can contribute to decisions about whether a patient’s symptoms warrant a urine culture, preventing unnecessary testing.
Ensuring cultures are collected correctly before initiating antibiotics, improving the accuracy of diagnostic results.
Prompting discussions about antibiotic treatment, including indication and duration, ensuring that these key aspects of therapy are regularly reviewed.
Improving the evaluation of penicillin allergies, helping to clarify true allergies and broaden the use of effective beta-lactam antibiotics when appropriate.

Accountability: Defined Leadership for Program Success

Effective antibiotic stewardship programs require designated leaders or co-leaders who are clearly accountable for program management and outcomes. A co-leadership model, often involving a physician and a pharmacist, has proven effective in many hospitals. According to the 2019 NHSN hospital survey, 59% of U.S. hospitals employ this co-leadership structure for their stewardship programs. Strong leadership, management, and communication skills are essential for those leading hospital antibiotic stewardship programs to ensure they can effectively drive change and improvement in patient care.

Figure 2: Illustration emphasizing the accountability aspect of antibiotic stewardship, showing program leaders taking responsibility for program outcomes.

In co-leadership models, clear delineation of responsibilities and expectations is crucial. This is particularly important for physician leaders who may not be full-time hospital staff. Because antibiotic prescribing ultimately falls under the purview of the medical staff, if a non-physician leads the program, it is essential for the hospital to designate a physician to serve as a point of contact and provide support to the non-physician leader. Regular “stewardship rounds” involving co-leaders or the non-physician lead and the supporting physician can strengthen program leadership and enhance visibility. Expanding these rounds to include discussions with prescribers, often referred to as “handshake stewardship,” has been shown to improve antibiotic use and effectively increase the visibility and support of the stewardship program amongst clinical staff.

Training in infectious diseases and/or antibiotic stewardship is highly beneficial for program leaders, equipping them with the specialized knowledge needed to guide effective interventions. Larger facilities often achieve success by hiring full-time staff dedicated to developing and managing stewardship programs. Smaller facilities, however, may utilize various arrangements, including part-time or even off-site expertise, sometimes referred to as tele-stewardship, to access the necessary expertise. Hospitalists have also emerged as effective physician leaders or supporters in efforts to improve antibiotic use, particularly in smaller hospitals. Their increasing presence in inpatient care, frequent use of antibiotics, and experience with leading hospital quality improvement projects make them valuable assets to stewardship programs.

Pharmacy Expertise: A Cornerstone of Antibiotic Stewardship

Highly effective hospital antibiotic stewardship programs consistently demonstrate strong engagement of pharmacists, either as program leaders or co-leaders. Identifying a pharmacist who is empowered to lead implementation efforts to improve antibiotic use is a critical step in establishing a successful ASP and enhancing patient care. Pharmacists with infectious diseases training are particularly effective in improving antibiotic use and often lead programs in larger hospitals and healthcare systems, bringing specialized knowledge in antimicrobial therapy.

Figure 3: Image highlighting the role of a pharmacist in antibiotic stewardship, emphasizing their expertise in medication management and optimization.

In hospitals without infectious diseases-trained pharmacists, general clinical pharmacists often serve as co-leaders or pharmacy leaders. These general clinical pharmacists are more effective when they receive specific training and/or gain experience in antibiotic stewardship, demonstrating the importance of continuous professional development in this specialized area.

Numerous resources are available to support the antibiotic stewardship efforts of clinical pharmacists. These range from readily accessible posters highlighting key stewardship interventions for pharmacists to more formal training and certificate programs in stewardship, providing pharmacists with various pathways to enhance their skills and contributions to ASPs.

Action: Implementing Effective Interventions to Improve Antibiotic Use

Antibiotic stewardship interventions are proven to improve patient outcomes by optimizing antibiotic use and reducing associated harms. An initial assessment of current antibiotic prescribing practices can help identify specific areas where interventions are most needed and can have the greatest impact on improving patient care.

Figure 4: Visual representation of action-oriented strategies in antibiotic stewardship, indicating interventions aimed at improving antibiotic use.

Priority Interventions to Enhance Antibiotic Use

Stewardship programs should strategically select interventions that best address identified gaps in antibiotic prescribing. Priority should be given to prospective audit and feedback, preauthorization, and the development and implementation of facility-specific treatment guidelines, as these have been shown to be most effective.

Published evidence consistently demonstrates that prospective audit and feedback (sometimes referred to as post-prescription review) and preauthorization are the two most effective antibiotic stewardship interventions in hospital settings. These interventions are strongly recommended in evidence-based guidelines and are considered “foundational” components of any robust hospital stewardship program.

Prospective audit and feedback involves an expert review of antibiotic therapy by a specialist in antibiotic use, providing suggestions to optimize therapy after the antibiotic has been prescribed. This approach differs from an antibiotic “timeout” because the stewardship program, rather than the treating team alone, conducts the audits, bringing specialized expertise to the review process.

Audit and feedback can be implemented in various ways, depending on the expertise available within the stewardship program. Programs with limited infectious diseases expertise might focus reviews on comparing prescribed treatments to hospital-specific treatment guidelines, particularly for common conditions like community-acquired pneumonia, urinary tract infections, or skin and soft tissue infections. Programs with more advanced infectious diseases expertise can undertake reviews of more complex antibiotic treatment courses, tailoring the level of intervention to the available resources and expertise.

The effectiveness of prospective audit with feedback can be further enhanced by providing feedback in face-to-face meetings with providers, often termed “handshake stewardship”. This personal interaction can improve provider engagement and acceptance of stewardship recommendations, leading to better outcomes.

Preauthorization requires prescribers to obtain approval before using certain antibiotics. This intervention can optimize initial empiric therapy by allowing for expert input on antibiotic selection and dosing at the outset, which can be life-saving in serious infections like sepsis. It can also prevent the unnecessary initiation of antibiotics, ensuring that these powerful drugs are used only when truly indicated.

Decisions about which antibiotics to place under preauthorization should be made in consultation with prescribers, focusing on opportunities to improve empiric use rather than solely on drug costs. Effective preauthorization requires readily available expertise and staff who can complete authorizations in a timely manner, avoiding delays in necessary treatment. Hospitals can customize the agents, clinical situations, and mechanisms (e.g., preauthorization through an electronic order entry system) for preauthorization based on program goals, available expertise, and resources, ensuring that it does not impede timely therapy for serious infections. Stewardship programs must also monitor for potential unintended consequences of preauthorization, particularly treatment delays, and adjust protocols as needed.

Two studies directly comparing prospective audit and feedback and preauthorization have found prospective audit and feedback to be more effective. However, many experts suggest that both interventions should be prioritized for implementation, as preauthorization can optimize the initiation of antibiotics, while prospective audit and feedback can optimize continued therapy, providing complementary benefits. Hospitals can utilize local data and knowledge of prescribing practices to determine which antibiotics should be subject to prospective audit and feedback and/or preauthorization, tailoring their approach to local needs and context.

Facility-specific treatment guidelines are also considered a priority intervention because they significantly enhance the effectiveness of both prospective audit and feedback and preauthorization. These guidelines establish clear recommendations for optimal antibiotic use within the hospital, streamlining decision-making and improving consistency of care. Treatment guidelines can optimize antibiotic selection and duration, particularly for common indications such as community-acquired pneumonia, urinary tract infections, intra-abdominal infections, skin and soft tissue infections, and surgical prophylaxis. Recommendations should be based on national guidelines but adapted to reflect hospital-specific treatment preferences, considering local susceptibility patterns, formulary options, and patient demographics.

Ideally, treatment guidelines should also address diagnostic approaches, including when to send diagnostic samples, what tests to perform, and indications for rapid diagnostics and non-microbiologic tests (e.g., imaging, procalcitonin). The development of treatment guidelines offers a valuable opportunity for stewardship programs to engage prescriber stakeholders, fostering consensus on optimal antibiotic use practices.

Hospital guidelines can also facilitate prospective audit with feedback and preauthorization by providing a clear benchmark against which prescriptions and requests for antibiotics can be compared. Stewardship programs can prioritize the development of guidelines based on the infections most commonly encountered at their facility, focusing resources where they are most needed. Adherence to hospital guidelines can be further enhanced by embedding treatment recommendations directly into order sets and clinical pathways within the electronic health record, making optimal choices easier for prescribers.

Common Infection-Based Interventions

More than half of all antibiotics used to treat active infections in hospitals are prescribed for three common infection types where there are substantial opportunities to improve use: lower respiratory tract infections (e.g., community-acquired pneumonia), urinary tract infections, and skin and soft tissue infections. Optimizing the duration of antibiotic therapy is especially important because infections are frequently treated for longer durations than recommended by guidelines. Data consistently show that each additional day of antibiotic use increases the risk of patient harm, underscoring the need for judicious use. Examples of infection-based interventions are detailed below:

Community-acquired pneumonia: Interventions in this area have focused on:

Improving diagnostic accuracy to ensure antibiotics are used appropriately for confirmed bacterial pneumonia and not for viral infections or non-infectious conditions that mimic pneumonia.
Tailoring therapy to culture results, ensuring that antibiotics are narrowed to the most specific and effective agents once culture and sensitivity data are available.
Optimizing the duration of treatment to align with guideline recommendations, preventing unnecessarily prolonged courses of antibiotics.

The use of viral diagnostics and/or procalcitonin testing may help identify patients in whom antibiotics can be safely discontinued because bacterial pneumonia is unlikely, reducing unnecessary antibiotic exposure. Optimizing the duration of therapy at hospital discharge is particularly important, as a significant portion of excess antibiotic use in the treatment of community-acquired pneumonia occurs after discharge, highlighting the need for careful discharge planning and patient education.

Urinary tract infection (UTI): A significant number of patients who receive antibiotics for UTIs actually have asymptomatic bacteriuria, a condition that generally does not require antibiotic treatment. Successful stewardship interventions in this area focus on avoiding the ordering of unnecessary urine cultures and preventing the treatment of asymptomatic bacteriuria, except in specific clinical situations where treatment is genuinely indicated (e.g., pregnancy, urologic procedures). For patients who do require treatment for symptomatic UTIs, interventions should focus on ensuring they receive appropriate therapy based on local susceptibility patterns and for the recommended duration, optimizing treatment effectiveness and minimizing resistance.

Skin and soft tissue infection: Interventions for skin and soft tissue infections have focused on ensuring that patients with uncomplicated infections do not receive antibiotics with overly broad spectra, such as unnecessary coverage for methicillin-resistant Staphylococcus aureus (MRSA) and gram-negative pathogens. Interventions also aim to optimize the route of administration (oral vs. intravenous), dosage, and duration of treatment, ensuring that therapy is tailored to the specific type and severity of infection and avoiding overtreatment.

Table 1. Key Opportunities to Improve Antibiotic Use in Common Infections

Condition	Diagnostic Considerations	Empiric Therapy	Definitive Therapy Tailor to culture results and define duration, including discharge prescription.
Community-acquired pneumonia	Review cases after initiation of therapy to confirm pneumonia diagnosis versus non-infectious etiology.	Avoid empiric use of antipseudomonal beta-lactams and/or MRSA agents unless clinically indicated.	Guidelines suggest that in adults, most cases of uncomplicated pneumonia can be treated for 5 days when a patient has a timely clinical response. Data also suggest that negative results of MRSA nasal colonization testing can help guide decisions to discontinue empiric therapy for MRSA pneumonia.
Urinary tract infection (UTI)	Implement criteria for ordering urine cultures to ensure that positive cultures are more likely to represent infection than bladder colonization. Examples include: – Order a urine culture only if the patient has signs and symptoms consistent with UTI such as urgency, frequency, dysuria, suprapubic pain, flank pain, pelvic discomfort or acute hematuria. For patients with urinary catheters, avoid obtaining urine cultures based solely on cloudy appearance or foul smell in the absence of signs and symptoms of UTI. Nonspecific signs and symptoms such as delirium, nausea and vomiting should be interpreted with caution as, by themselves, they have a low specificity for UTI.	Establish criteria to distinguish between asymptomatic and symptomatic bacteriuria. Avoid antibiotic therapy for asymptomatic bacteriuria except in certain clinical situations where treatment is indicated, such as for pregnant women and those undergoing an invasive genitourinary procedure.	Use the shortest duration of antibiotic therapy that is clinically appropriate.
Skin and soft tissue infection	Develop diagnostic criteria to distinguish purulent and non-purulent infections and severity of illness (i.e., mild, moderate and severe) so that skin and soft tissue infections can be managed appropriately according to guidelines.	Avoid empiric use of antipseudomonal beta-lactams and/or anti-anaerobic agents unless clinically indicated. Use of therapy specific for MRSA may not be necessary in uncomplicated non-purulent cellulitis.	Guidelines suggest that most cases of uncomplicated bacterial cellulitis can be treated for 5 days if the patient has a timely clinical response.

Other Infection-Based Interventions

Sepsis: Early and effective antibiotic administration is life-saving in sepsis. Antibiotic stewardship programs should collaborate closely with sepsis experts within the hospital, as well as the pharmacy and microbiology laboratory, to optimize sepsis treatment protocols. Important issues to address include:

Developing antibiotic recommendations for sepsis that are tailored to local microbiology data and resistance patterns, ensuring empiric therapy is likely to be effective against local pathogens.
Establishing protocols to ensure rapid administration of antibiotics in cases of suspected sepsis, as timely therapy is critical for improving outcomes.
Implementing mechanisms to review antibiotics initiated for suspected sepsis, enabling therapy to be tailored or discontinued if deemed unnecessary once more diagnostic information becomes available, preventing unnecessary antibiotic use.

Staphylococcus aureus infection: In many cases of suspected MRSA infection, therapy can be de-escalated if MRSA infection is ruled out or narrowed to a beta-lactam antibiotic if the infection is confirmed to be methicillin-susceptible S. aureus. Studies have also shown that standardized treatment protocols and infectious diseases consultation, when available, can improve outcomes in patients with S. aureus bloodstream infections, highlighting the value of expert guidance in managing these serious infections.

C. difficile infection: Treatment guidelines for C. difficile infection recommend that providers discontinue unnecessary antibiotics in all patients diagnosed with this infection. Reviewing current antibiotic regimens in patients with new C. difficile diagnoses can identify opportunities to stop unnecessary antibiotics, which can improve the clinical response to C. difficile treatment and reduce the risk of recurrence. Stewardship programs can also ensure that patients are receiving guideline-recommended therapy for their C. difficile infection, optimizing treatment and improving patient outcomes.

Culture-proven invasive infection: Invasive infections, such as bloodstream infections, present significant opportunities for stewardship interventions because they are readily identified through microbiology results, and suboptimal therapy can lead to worse outcomes. Prospective audit and feedback of new culture or rapid diagnostic results can be particularly beneficial in reducing the time to discontinue, narrow, or broaden antibiotic therapy as appropriate, ensuring timely and targeted treatment adjustments.

Review of planned outpatient parenteral antibiotic therapy (OPAT): In certain cases, planned OPAT can be optimized or even avoided altogether following a review by the antibiotic stewardship program, preventing unnecessary outpatient antibiotic use and associated risks and costs.

Provider-Based Interventions

Antibiotic “timeouts”: Antibiotics are frequently started empirically in hospitalized patients. However, providers may not always revisit the initial antibiotic selection after more data becomes available, including culture results and clinical progress. An antibiotic timeout is a provider-led reassessment of the continued need for and choice of antibiotics, typically conducted when the clinical picture is clearer and more diagnostic information, especially results of cultures and rapid diagnostics, is available.

Antibiotic timeouts differ from prospective audit and feedback in that the reviews are conducted by the treating providers, not the stewardship team. While a clinical trial demonstrated that antibiotic timeouts at 48-72 hours of therapy improved the appropriateness of antibiotic selection, it did not significantly reduce overall antibiotic use. Antibiotic timeouts are a valuable supplemental intervention but should not be considered a substitute for prospective audit and feedback by the stewardship program, which provides a more specialized and expert-driven review.

The optimal timing of antibiotic timeouts has not been definitively established. Experts suggest that daily reviews of antibiotic selection, until a definitive diagnosis and treatment duration are established, can help optimize treatment decisions. Provider-led reviews of antibiotics can focus on four key questions:

Does this patient have an infection that will respond to antibiotics? Ensuring antibiotics are only used when truly indicated for bacterial infections.
Have proper cultures and diagnostic tests been performed? Confirming that appropriate diagnostic workup has been completed to guide targeted therapy.
Can antibiotics be stopped or improved by narrowing the spectrum (de-escalation) or changing from intravenous to oral administration? Optimizing antibiotic therapy to be as targeted and least invasive as possible.
How long should the patient receive the antibiotic(s), considering both the hospital stay and any post-discharge therapy? Planning for appropriate antibiotic duration and discharge prescriptions to ensure optimal treatment and prevent recurrence.

Assessing penicillin allergy: Approximately 15% of hospitalized patients report a penicillin allergy. However, less than 1% of the U.S. population has a true, severe penicillin allergy that would preclude treatment with a beta-lactam antibiotic. Several effective approaches exist to accurately assess penicillin allergies, including detailed history and physical examination, challenge doses, and skin testing. Nurses can play a crucial role in improving penicillin allergy assessments by gathering detailed allergy histories and facilitating further evaluation when needed, thereby enabling the use of preferred beta-lactam antibiotics when appropriate.

Pharmacy-Based Interventions

The following interventions are often initiated by pharmacists and/or embedded into the pharmacy sections of electronic health records, streamlining implementation and enhancing efficiency:

Documentation of indications for antibiotics: Requiring documentation of the indication for each antibiotic prescription can facilitate other stewardship interventions, such as prospective audit and feedback, and optimize post-discharge durations of therapy. Documentation itself can also promote more thoughtful antibiotic prescribing by prompting prescribers to clearly define the reason for antibiotic use.
Automatic changes from intravenous to oral antibiotic therapy: Automatically transitioning patients from intravenous to oral antibiotics, when clinically appropriate and for antibiotics with good oral bioavailability, can improve patient safety by reducing the need for central or peripheral intravenous access and its associated risks.
Dose adjustments: Ensuring timely dose adjustments when needed, such as in cases of organ dysfunction, particularly renal impairment, or based on therapeutic drug monitoring, optimizes antibiotic efficacy and minimizes toxicity.
Dose optimization: Implementing dose optimization strategies, for example, extended-infusion administration of beta-lactams, especially for critically ill patients and those infected with drug-resistant pathogens, can improve antibiotic pharmacodynamics and clinical outcomes.
Duplicative therapy alerts: Implementing alerts within the pharmacy system to identify situations where antibiotic therapy might be unnecessarily duplicative, such as concurrent use of multiple agents with overlapping spectra (e.g., anaerobic activity or resistant Gram-positive activity), helps prevent redundant antibiotic use.
Time-sensitive automatic stop orders: Utilizing time-sensitive automatic stop orders for specific antibiotic prescriptions, particularly antibiotics administered for surgical prophylaxis, ensures that prophylactic antibiotics are discontinued at the appropriate time, preventing prolonged and unnecessary use.
Detection and prevention of antibiotic-related drug-drug interactions: Implementing systems to detect and prevent antibiotic-related drug-drug interactions, for example, interactions between some orally administered fluoroquinolones and certain vitamins or other medications, enhances patient safety and prevents adverse events.

Microbiology-Based Interventions

The microbiology laboratory, in collaboration with the stewardship program, frequently implements the following interventions, leveraging their expertise in diagnostics and antimicrobial resistance:

Selective reporting of antimicrobial susceptibility testing results: Tailoring antimicrobial susceptibility reports to selectively report only the most appropriate and cost-effective antibiotics for specific infections, based on formulary and local resistance patterns, can guide prescribers toward optimal antibiotic choices and discourage the use of broader-spectrum agents when narrower-spectrum drugs are effective.
Implementing and promoting the use of rapid diagnostic tests: Introducing and promoting the use of rapid diagnostic tests for bacterial infections can significantly reduce the time to pathogen identification and susceptibility results. This allows for earlier de-escalation of empiric therapy to more targeted and effective agents, improving patient care and reducing unnecessary broad-spectrum antibiotic use.
Providing cumulative antibiograms: Regularly generating and disseminating cumulative antibiograms that summarize local antibiotic resistance patterns for common pathogens allows clinicians to make informed decisions about empiric antibiotic therapy, ensuring that initial antibiotic choices are likely to be effective against prevalent local organisms.

Nursing-Based Interventions

Bedside nurses are front-line healthcare providers who can initiate the following important stewardship interventions, given their constant patient interaction and medication administration responsibilities:

Optimizing microbiology cultures: Nurses play a crucial role in ensuring that microbiology cultures are obtained appropriately, using proper techniques to minimize contamination and adhering to established indications for culture collection, especially for urine cultures, to avoid unnecessary testing and treatment of colonization.
Intravenous to oral transitions: Nurses are often the first to recognize when patients are clinically improving and able to tolerate oral medications. They can proactively initiate discussions with physicians about transitioning patients from intravenous to oral antibiotics, facilitating timely switches and reducing the risks associated with intravenous access.
Prompting antibiotic reviews (“timeouts”): Nurses are well-positioned to track how long a patient has been receiving an antibiotic and when laboratory results become available. They can play a key role in prompting re-evaluations of antibiotic therapy at specified times, such as after 48 hours of treatment or when culture results become available, ensuring timely reassessment of antibiotic regimens and optimization of therapy.

Tracking: Measuring Impact and Identifying Opportunities for Improvement

Measurement is a critical component of antibiotic stewardship programs. It is essential for identifying areas where improvements in antibiotic use are needed and for objectively assessing the impact of implemented interventions on patient care and antibiotic prescribing practices. Measurement in antibiotic stewardship involves evaluating both processes (whether policies and guidelines are being followed) and outcomes (whether interventions are improving patient outcomes and antibiotic use).

Figure 5: Graphic emphasizing data tracking in antibiotic stewardship, highlighting the use of metrics to assess program effectiveness.

Antibiotic Use Measures

Monitoring and benchmarking antibiotic use is important for hospitals. Electronically reporting antibiotic use data to the National Healthcare Safety Network (NHSN) Antimicrobial Use (AU) Option is a valuable tool for this purpose. The NHSN AU Option is available to hospitals with the information system capabilities to submit electronic medication administration records (eMAR) and/or bar-coding medication administration records (BCMA) using HL7 standardized clinical document architecture.

Numerous health information technology companies offer solutions to facilitate the reporting of antibiotic use data to the AU Option, making this process more accessible for hospitals. Stewardship programs should collaborate with their information technology staff to explore options for reporting data to the AU Option. Enrolling hospitals in the NHSN AU Option is a priority goal set by the National Strategy for Combating Antibiotic-Resistant Bacteria and the President’s Advisory Committee on Combating Antibiotic Resistant Bacteria, underscoring the national importance of this data collection effort.

The NHSN AU Option provides standardized rates of antibiotic use, expressed as days of therapy (DOTs) per days present, for nearly all antibiotics. These rates are available for individual inpatient care locations, select outpatient care locations (e.g., emergency department and observation units), and for the entire hospital, offering a comprehensive view of antibiotic use across the facility. Days of therapy are calculated as the sum of days for which any amount of a specific antibiotic agent is administered to a patient, providing a consistent and clinically relevant measure of antibiotic exposure.

The AU Option also provides a risk-adjusted benchmark of antibiotic use known as the Standardized Antimicrobial Administration Ratio, or “SAAR.” Benchmarking has proven to be a powerful tool in hospital quality improvement initiatives. The SAAR compares observed antibiotic use to predicted use, with predicted use based on risk-adjustment models derived from data submitted to the NHSN AU Option. SAARs have been developed for various groups of antibiotics and for adult, pediatric, and neonatal care locations, in response to input from stewardship experts seeking actionable and comparative data. Stewardship programs are increasingly using the NHSN AU Option to both inform the design of interventions and assess their impact on antibiotic use patterns.

Hospitals not yet reporting to the NHSN AU Option can often obtain antibiotic use data from their pharmacy record systems, typically in the form of days of therapy or defined daily doses (DDDs). The DDD estimates antibiotic use by aggregating the total grams of each antibiotic purchased, ordered, dispensed, or administered during a specific period, divided by the World Health Organization-assigned DDD for that antibiotic. However, U.S. guidelines recommend using days of therapy rather than DDDs as the preferred metric for measuring hospital antibiotic use, as DOTs are considered more clinically meaningful and directly reflect patient exposure to antibiotics.

Outcome Measures

C. difficile infections are a critical target for stewardship programs, given the strong evidence that improved antibiotic use can prevent these infections. Most acute care hospitals already monitor and report data on C. difficile infections to NHSN as part of payment programs for CMS and/or state requirements. C. difficile infection prevention is a multifaceted effort, providing an excellent opportunity for stewardship programs to collaborate with other hospital departments, such as the laboratory and infection prevention, to achieve shared goals.

Antibiotic Resistance. Improving antibiotic use is fundamentally important for mitigating antibiotic resistance, making resistance rates another key outcome measure for stewardship programs. While the development and spread of antibiotic resistance are multifactorial, and studies assessing the direct impact of improved antibiotic use on resistance rates have shown mixed results, reducing overall antibiotic pressure is a crucial long-term strategy. The impact of stewardship interventions on resistance is best assessed when measurement focuses on pathogens recovered from patients after hospital admission, when they are more likely to be influenced by hospital stewardship interventions. Monitoring resistance at the patient level (e.g., the percentage of patients developing resistant superinfections) has also proven to be a useful metric. Hospitals can also track antibiotic resistance trends through the NHSN Antimicrobial Resistance (AR) Option, providing a standardized platform for data collection and analysis.

Financial Impact. Stewardship programs can achieve significant cost savings, particularly through reductions in drug expenditures. While cost reduction should not be the primary goal of a stewardship program (patient care improvement is paramount), demonstrating cost savings can be helpful in securing continued resources and support for ASPs from hospital administration. If hospitals track antibiotic costs, it is important to assess the rate at which antibiotic costs were rising before the stewardship program was implemented to accurately gauge the program’s financial impact. After an initial period of marked savings, costs often stabilize. However, it is crucial to maintain ongoing support for stewardship programs, as costs can increase again if programs are discontinued, highlighting the sustained value of these programs.

Process Measures for Quality Improvement

Process measures focus on evaluating the specific interventions implemented by the hospital, providing insights into program implementation and areas for refinement.

Priority Process Measures

Tracking the types and acceptance rates of recommendations from prospective audit and feedback interventions. This data can pinpoint areas where further education or more targeted interventions might be beneficial, as well as assess the effectiveness of the audit and feedback process itself.
Monitoring preauthorization interventions by tracking agents being requested for specific conditions and ensuring that preauthorization is not causing delays in therapy. This monitoring ensures that preauthorization is functioning as intended, optimizing antibiotic use without impeding timely access to necessary medications.
Monitoring adherence to facility-specific treatment guidelines. If feasible, tracking adherence by individual prescriber can provide valuable feedback and identify areas for targeted education and support to improve guideline adoption across the medical staff.

Additional Process Measures

Monitoring the performance of antibiotic timeouts to assess how frequently they are conducted and whether opportunities to improve antibiotic use are being identified and acted upon. This assessment helps determine the effectiveness of timeout implementation and identify potential barriers to their consistent use.
Performing medication use evaluations to assess courses of therapy for selected antibiotics or infections. These evaluations can pinpoint opportunities to improve antibiotic use for specific agents or conditions. Standardized tools or antibiotic audit forms can facilitate these reviews, ensuring consistency and comprehensiveness.
Monitoring the frequency of intravenous to oral antibiotic conversions to identify missed opportunities for timely switches. This metric highlights areas where protocols for IV-to-oral conversion could be improved or reinforced to reduce unnecessary intravenous antibiotic use.
Assessing how often patients are prescribed unnecessary duplicate antibiotic therapy. This monitoring identifies instances of redundant antibiotic use, allowing for interventions to streamline regimens and reduce polypharmacy.
Assessing how often patients are discharged on the correct antibiotics for the recommended duration. This measure ensures that patients are discharged with appropriate antibiotic prescriptions, optimizing post-discharge care and preventing undertreatment or overtreatment.

Reporting: Communicating Data for Action

Antibiotic stewardship programs should provide regular updates to prescribers, pharmacists, nurses, and hospital leadership. These reports should include process and outcome measures that address both national and local issues, including antibiotic resistance trends. Antibiotic resistance information should be prepared in collaboration with the hospital’s microbiology laboratory and infection control and healthcare epidemiology department, ensuring accurate and clinically relevant data. The local or state health department’s healthcare infection control and antibiotic resistance program is also a valuable resource for local information on antibiotic resistance threats, providing regional context for hospital-level data. Summary information on antibiotic use and resistance, along with antibiotic stewardship program activities and successes, should be regularly shared with hospital leadership and the hospital board, keeping them informed and engaged in stewardship efforts.

Figure 6: Illustration of data reporting in antibiotic stewardship, emphasizing the importance of communicating findings to stakeholders for continuous improvement.

Findings from medication use evaluations, along with summaries of key issues identified during prospective audit and feedback reviews and preauthorization requests, are particularly useful to share with prescribers, providing targeted and relevant feedback on their prescribing practices. Disseminating facility-specific information on antibiotic use can be a powerful tool to motivate improved prescribing, especially when wide variations in use patterns exist among similar patient care locations, highlighting areas where standardization and best practices can be promoted. Provider-specific reports with peer comparisons have been effective in improving antibiotic use in outpatient settings, and while experience with these reports in hospital settings is still developing, they hold promise as a tool for driving individual and departmental improvement in antibiotic stewardship.

Education: Empowering Staff and Patients

Education is a critical component of comprehensive efforts to improve hospital antibiotic use. However, it is important to recognize that education alone is generally not an effective stewardship intervention when implemented in isolation. Education is most impactful when paired with active interventions and consistent measurement of outcomes, creating a multifaceted approach to behavior change. Various educational methods can be employed to promote optimal antibiotic use, including didactic presentations in both formal and informal settings, messaging through posters, flyers, newsletters, and electronic communications to staff groups.

Figure 7: Image representing education in antibiotic stewardship, emphasizing the importance of training and awareness programs.

Education is most effective when it is case-based and directly relevant to clinical practice. Prospective audit with feedback and preauthorization are both excellent methods for providing ongoing education on antibiotic use within the context of real patient cases. This is especially effective when feedback is delivered in person, such as through “handshake stewardship,” allowing for immediate clarification and personalized learning. Some hospitals utilize de-identified case reviews with providers to collectively analyze antibiotic therapy decisions and identify opportunities for improvement, fostering a culture of continuous learning and peer feedback. Education should be tailored to the specific actions most relevant to the target provider group, such as providing education on community-acquired pneumonia guidelines for hospitalists or focusing on proper culture techniques for nurses, ensuring that education is practical and directly applicable to their daily work. Numerous educational materials on hospital antibiotic use and stewardship are also available from the Agency for Healthcare Research and Quality’s Safety Program for Improving Antibiotic Use, providing readily accessible resources for program development and implementation.

Patient education is also an important focus for antibiotic stewardship programs. Patients should be informed about the antibiotics they are receiving, the reasons for their use, potential adverse effects, and any signs or symptoms they should report to healthcare providers. Patients should be alerted to potential side effects that may occur even after discharge and after they have completed their antibiotic course. Engaging patients in the development and review of educational materials can enhance their effectiveness by ensuring they are patient-centered and easily understood. Nurses are particularly important partners in patient education efforts, given their frequent interactions with patients and their role in medication administration and patient teaching. Nurses should be actively involved in developing educational materials and directly educating patients about appropriate antibiotic use and the importance of stewardship.

Conclusion: Enhancing Patient Care through Effective Infection Control Programs

Antibiotic stewardship programs represent a crucial aspect of modern healthcare, serving as essential infection control programs that significantly improve patient care. By optimizing antibiotic use, these programs not only combat the growing threat of antibiotic resistance but also directly enhance patient safety and treatment outcomes. The CDC’s Core Elements of Hospital Antibiotic Stewardship Programs provide a robust framework for hospitals to develop, implement, and refine their stewardship efforts. As demonstrated by numerous studies and the increasing adoption of these programs nationwide, antibiotic stewardship is not merely a best practice—it is a necessary component of high-quality healthcare. Through leadership commitment, accountability, specialized expertise, targeted actions, diligent tracking, transparent reporting, and comprehensive education, hospitals can effectively improve antibiotic use, leading to better patient outcomes, reduced healthcare costs, and a stronger defense against antibiotic resistance. Embracing and continuously improving antibiotic stewardship programs is a fundamental step towards ensuring safer and more effective healthcare for all patients.

CDC Efforts to Support Antibiotic Stewardship

The Core Elements of Hospital Antibiotic Stewardship Programs is part of a broader suite of documents and initiatives from the CDC designed to improve antibiotic use across the entire spectrum of healthcare settings. Building upon the hospital Core Elements framework, the CDC has also developed specific guides for other healthcare settings, including outpatient settings, long-term care facilities, and health departments, ensuring a comprehensive approach to antibiotic stewardship across the healthcare continuum.

The CDC has also published an implementation guide specifically tailored for small and critical access hospitals, recognizing their unique challenges and resource constraints. Implementation of Antibiotic Stewardship Core Elements in Small and Critical Access Hospitals provides practical advice and strategies for these facilities to effectively implement stewardship programs.

The CDC continues to utilize a variety of data sources, including the NHSN annual survey of hospital stewardship practices and the AU Option, to identify ongoing opportunities to optimize hospital antibiotic stewardship programs and practices. The agency remains committed to collaborating with a wide array of partners who share the common goal of improving antibiotic use, fostering a collaborative and collective approach to addressing this critical public health challenge.

With stewardship programs now established in the majority of U.S. hospitals, the focus is increasingly shifting towards optimizing these programs to achieve even greater impact. The CDC recognizes that ongoing research is essential to identify more effective implementation strategies for proven stewardship practices, as well as to discover new and innovative approaches to further enhance antibiotic stewardship. The CDC remains dedicated to supporting research efforts aimed at finding cutting-edge solutions to the persistent challenges of antibiotic stewardship and resistance.

Implementation Resources

Pharmacy Expertise
Action
Tracking
Education

For Health Departments

The Core Elements of Antibiotic Stewardship for Health Departments outlines the structure of state and local health department stewardship programs and provides antibiotic stewardship implementation strategies, extending the reach of stewardship efforts beyond individual healthcare facilities.

Core Elements of Antibiotic Stewardship for Health Departments