Erin Broaddus

Rao Fu

Hospital-Acquired Infections


            The World Health Organization offers several definitions of a nosocomial infection/ hospital \x96acquired infection: 

 An infection acquired in [a] hospital by a patient who was admitted for a reason other than that infection (1). An infection occurring in a patient in a hospital or other health care facility in whom the infection was not present or incubating

at the time of admission. This includes infections acquired in the hospital but appearing after discharge, and also occupational infections among staff of the facility (2).\x94[1]

As a general timeline, infections occurring more than 48 hours after admission are usually considered nosocomial.  Nosocomial infections are also divided into two classes, endemic or epidemic.[2] Most are endemic, meaning that they are at the level of usual occurrence within the setting.[3]  Epidemic infections occur when there is an unusual increase in infection above baseline for a specific infection or organism.[4]

Nosocomial infections occur worldwide, both in the developed and developing world.  They are a significant burden to patients and public health.  They are a major cause of death and increased morbidity in hospitalized patients.  They may cause increased functional disability and emotional stress and may lead to conditions that reduce quality of life.  Not only do they affect the general health of patients, but they are also a huge burden financially.   The greatest contributors to these costs are the increased stays that patients with nosocomial infections require.  The increased length of stay varies from 3 days for gynecological procedures to 19.8 days for orthopedic procedures.  Other costs include additional drugs, the need for isolation, and the use of additional studies.  There are also indirect costs due to loss of work. 

Nosocomial infections are most frequently infections of the urinary tract, surgical wounds, and the lower respiratory tract.  A World Health Organization prevalence study and other studies have shown that these infections most commonly occur in intensive care units and in acute surgical and orthopedic wards.  Infection rates are also higher in patients with increased susceptibility due to old age, underlying disease, or chemotherapy.

Patients are exposed to a variety of microorganisms during a hospital stay, but contact between a patient and an organism does not necessarily guarantee infection.  Other factors influence the nature and frequency of infections.  Organisms vary in resistance to antimicrobials and in intrinsic virulence.  Bacteria, viruses, fungi, and parasites can all cause nosocomial infections.  There are multiple ways of acquiring such an organism.  The organisms can be transferred from one patient to another (cross-infection).  They can be part of a patient\x92s own flora (endogenous infection).  They can be transferred from an inanimate object or from a substance recently contaminated by another human source (environmental transfer).  The organisms that cause most hospital acquired infections are common in the general population, in which setting they are relatively harmless.  They may cause no disease or a milder form of disease than in hospitalized patients.  This group includes Staphylococcus aureus, coagulase-negative staphylococci, enterococci, and Enterobacteria.  Factors that increase a patient\x92s susceptibility to nosocomial infections include young or old age, decreased immune resistance, underlying disease, and therapeutic and diagnostic interventions.[5] 

The organisms that cause nosocomial infections are often drug-resistant.  The regular use of antimicrobials for treatment therapy or prophylaxis promotes the development of resistance.  Through antimicrobial-driven selection and the exchange of genetic resistance elements, multi-drug resistant strains of bacteria emerge.  Antimicrobial-sensitive microorganism that are part of the endogenous flora are suppressed, while the resistant strains survive.[6]  Many strains of pneumococci, staphylococci, enterococci, and tuberculosis are currently resistant to most or all antimicrobials which were once effective.[7]


Types of Nosocomial Infections

The four most common types of nosocomial infections are urinary infections, surgical site infection, nosocomial pneumonia, and nosocomial bacteremia.  Urinary infections are by far the most common.  Eighty percent of these infections are associated with the use of an indwelling catheter.  They are associated with less morbidity than other infections but can sometimes lead to septicemia and death.  Surgical infections are also frequent with an incidence varying from 0.5% to 15% depending on the type of surgery and the underlying patient status.  A surgical infection is indicated by the presence of purulent discharge around the wound or the insertion site of a drain, or by the presence of cellulites which is emanating from the wound.[8]  Patients usually acquire the infection during the procedure itself, either endogenously from flora on the skin or in the operative site, exogenously from air, medical equipment, doctors, or other staff, or rarely, from blood given during the procedure.  The extent of contamination during the surgery is the main risk factor.  Contamination varies with the length of the procedure and the patient\x92s general condition. 

Nosocomial pneumonia is also a significant problem.  About 3% of patients on ventilators acquire pneumonia, which in this circumstance, has a very high case-fatality rate.  The source of the microorganism is often endogenous but may also be exogenous with transfer of an organism from the respiratory equipment.[9] In one example of successful reduction of ventilator-associated pneumonia (VAP), the Owensboro Medical Health System was able to reduce their rate of VAP in the ICU to zero for eight months.  They implemented the Ventilator Bundle, a series of interventions related to ventilator care.  The main interventions include elevation of the head of the bed, assessment of the readiness for extubation, daily \x93sedation\x94 vacations, peptic ulcer prophylaxis, and deep venous thrombosis prophylaxis.  The Owensboro team particularly noted the importance of elevating the head of the bed, citing an observed association of inability to elevate the head of the bed due to clinical condition and VAP.  The team also noted the importance of getting \x93buy-in\x94 from the nursing staff,  making changes as easy as possible for the nursing staff, teaching new staff members the importance of the ventilator bundle, identifying a physician champion of the intervention, and remembering that cultural changes take time.[10] Besides ventilator-associated pneumonia, there are also problems with viral bronchiolitis in children\x92s units and influenza with secondary bacterial pneumonia in institutions for the elderly.[11] 

Nosocomial bacteremia, a fourth type of nosocomial infection, represents about 5% of nosocomial infections.  Although they are only a small proportion of nosocomial infections, they have high case-fatality rates, sometimes greater than 50%.  These infections may occur at the entry site of the intravascular device or along the path of a catheter (tunnel infection).  The sources of infection-causing microorganism for these infections are endogenous.  Besides these four most common and important types of infections, there can also be skin and soft tissue infection, gastroenteritis, endometritis, sinusitis and other enteric infections.[12] 

In a survey of 6,290 pediatric ICU patients between 1992 -1997, the following data on nosocomial infections due to bacteria and fungi were acquired:


Nosocomial Infections Due to Bacteria and Fungi in Pediatric ICU Patients



Nosocomial Etiologies

Common Treatments

Bloodstream Infections


Coagulase-negative staphylococci, 40%

Enterococci, 11.2%

Fungi, 9.65%

Staphylococcus aureus, 9.3%

Enterobacter species, 6.2%

Pseudomonads, 4.9%


Consideration of Line Removal

Broad-spectrum antibiotics according to susceptibility of microbials



Ventilator Associated Pneumonia



Guided use of broad-spectrum antibiotics

Macrolide use for legionellosis


Anti-influenza therapy

Vaccination against influenza A and B

Urinary Tract Infection


Gram-negative enterics, 50%

Fungi, 25%

Enterococci, 10%

Indwelling catheters should be removed, if possible

Antibiotic and antifungal therapy based on lab tests

Lower respiratory infection




Gastrointestinal, skin, soft tissue, cardiovascular infections




Surgical-site infections


S aureus, 20%

Pseudomonads, 16%

Coagulase-neg staphylococci, 15%

Enterococci, fungi, Enterobacter species, and Escherichia coli, less than 10% each

Combination of surgical care and aggressive antibiotic therapy

Surgical debridement

Ear, nose, and throat infections




They note that viral infections are actually the most common etiologies of nosocomial infections, causing many viral respiratory infections and rotaviral infections in winter, and many enteroviral infections in the summer.  Treatment for all patients includes treatment of shock, hypoventilation, and other complications as well as administration of empiric antibacterials, antifungals, and antivirals.  These patients often require expert care from an ICU team and the involvement of infectious disease specialists, burn care specialists, and surgical teams.[13]


Nosocomial Infection Causing Organisms

As discussed earlier, many different types of pathogens can cause nosocomial infections.  The most common are bacteria, including commensal bacteria, which are part of the normal flora, and pathogenic bacteria, which come from an exogenous source.  Commensal bacteria normally have a protective role against pathogenic bacteria but can cause infection when the host is compromised.  Pathogenic bacteria are more virulent and can cause infections regardless of host status. Viruses including Hepatitis B and C, Respiratory Synctial Virus, rotaviruses, and enteroviruses may also be transmitted nosocomially.  During times of prolonged antibiotic treatment and severe immunosuppression, fungi and other opportunistic organisms can cause infections.  This group includes Candida albicans, Aspergillus spp., Cryptococcus neoformans, Cryptosporidium.[14]


Methods of Acquisition

Bacteria that cause nosocomial infections can be acquired in several ways.  Endogenous infections can develop from the endogenous or transient flora of the patient.  When bacteria present in the normal flora are transmitted to sites outside of their normal environment like the urinary tract, they can cause infection.  Infection can also occur with tissue damage (wound) or with inappropriate antibiotic therapy that allows overgrowth of endogenous bacteria like C. difficile.[15]  Exogenous cross-infection can occur with transfer of an organism from one patient or member of the staff to another patient or member of staff.  The WHO guide summarizes this idea with the following statement:

Bacteria are transmitted between patients: (a) through direct contact between patients hands, saliva droplets or other body fluids), (b) in the air (droplets or dust contaminated by a patient\x92s bacteria), (c) via staff contaminated through patient care (hands, clothes, nose and throat) who become transient or permanent carriers, subsequently transmitting bacteria to other patients by direct contact during care, (d) via objects contaminated by the patient (including equipment), the staff\x92s hands, visitors or other environmental sources (e.g. water, other fluids, food).[16]

A final route of acquisition is through flora from the healthcare environment.  Certain microorganisms do well in the hospital environment.  They may live in water, in damp areas, in sterile products or disinfectants (Pseudomonas, Acinetobacter, Mycobacterium), in linens, in food, in fine dust and droplet nuclei, and in equipment and supplies used in care.

            People are central to all of these routes of transmission. They are the main reservoir and source for microorganisms.  They are the main transmitters of organisms, and they are the receptors of organisms, in consequence becoming new reservoirs. [17]


Antimicrobial Use and Resistance

            There are many problems today in the use of antimicrobials.  Problems include overprescribing, administration of suboptimal doses, too short of a treatment period, and misdiagnosis leading to an inappropriate choice of agent.  These problems lead to the emergence of resistant organisms that are spread when hand washing, barrier precautions and equipment cleaning are not optimal.[18]  The World Health Organization offers guidelines for effective prescribing.  They maintain that each healthcare facility should have its own effective use program.  Some general guidelines include prescribing an antimicrobial with as narrow a spectrum as possible, using an antimicrobial that can be justified by the clinical diagnosis, and obtaining appropriate specimens for bacteriological examination prior to initiation of treatment.  Using an appropriate dose is also emphasized; too low of a dose may not treat the infection and may also promote resistance.  The WHO guide summarizes these ideas with the statement, \x93The aim of antimicrobial therapy is to choose a drug that is selectively active against the most likely pathogen(s) and the least likely to cause adverse effects or promote resistance.\x94[19] 

            When transmission of resistant organisms does occur, specific control measures must be instituted.  These resistant organisms often cause nosocomial infections.  Infection control measures for containing outbreaks of antimicrobial resistant organisms begin with identifying reservoirs such as colonized and infected patients and environmental contamination.  The next step is stopping transmission by improving hand washing and asepsis, isolating colonized and infected patients, removing common sources, disinfecting the environment, and closing units to new admissions if necessary.  The final control measure is to modify a patient\x92s risk by controlling antibiotic use and removing compromising factors.[20]

            Some strains of methicillin-resistant Staphylococcus aureus are particularly capable of causing nosocomial infections.  These strains are often resistant to multiple antibiotics and sometimes are only sensitive to vancomycin and teicoplanin.  Infections caused by MRSA are similar to those caused by methicillin sensitive strains (wound infections, lower respiratory and urinary tract infections, septicemia, infections of sites for invasive devices, pressures sores, burns and ulcers.  MRSA has the potential for epidemic spread, regionally and nationally.  Vancomycin-resistant enterococci are also known causes of nosocomial infections. [21]

            The WHO suggests that all hospitals should have an Antimicrobial Use Committee.  This Committee ought to have a \x93simple, flexible and regularly updated antibiotic-prescribing policy on a disease specific basis, relying whenever possible on knowledge of prevailing antibiotic-sensitivity patterns and controlled use of reserve antibiotics.\x94[22]  The hospital microbiology laboratory is very important in controlling antibiotic resistance.  This lab should test for susceptibility, work with the Antimicrobial Use Committee, monitor and report trends in the prevalence of bacterial resistance to antimicrobial agents, and notify infection control of any unusual patterns of bacterial resistance.  Antimicrobial use in healthcare facilities must be monitored, usually by the pharmacy department.  These data are then reported to the Antimicrobial Use Committee and the Medical Advisory Committee.  Occasional audits should then be undertaken to determine the appropriateness of antimicrobial use.[23]


The Societal Impact of Nosocomial Infections

            One study estimates that bloodstream nosocomial infections are the eighth leading cause of death, assuming a nosocomial infection rate of 5%, of which 10% are bloodstream infections, and an attributable mortality rate of 15%.  In absolute numbers, if the overall attack rate was 5%, and 25 million patients were admitted each year, 1.75 million people would acquire nosocomial infections each year.  If 10% of these were bloodstream infections, 175,000 would get these serious infections each year.  If the attributable mortality rate of nosocomial infections is 20% and the infection rate is 5%, an estimated 350,000 life years would be lost annually.[24]  Another source reports an incidence of 2 million new cases of nosocomial infections per year, leading to an estimated 20,000 deaths per year.  They also estimate that nosocomial infections more than double the mortality and morbidity risks of any patient admitted to a hospital.[25]        The costs to society can also be studied in terms of dollars spent.  Assuming an incidence of 2 million nosocomial infections per year, the estimated added expenditure is in excess of $2,000,000,000 per year[26].    One study showed that length of stay for a patient with a Staphylococcus aureus infection was increased by nearly three times the average length of stay for any other type of hospitalization.   This increased length of stay also means increased costs.  Treating a methicillin-resistant Staphylococcus aureus (MRSA) infection costs 6-10% more than treating a S. aureus infection that is sensitive to methicillin (MSSA).  Patients with MRSA infections also have a higher attributable death rate than MSSA patients.  These statistics support the argument for increasing efforts to reduce the incidence of hospital-acquired infections so that the associated societal costs will also be reduced.[27]

            As a public health problem, nosocomial infections will become increasingly important in the future.  Crowding and population size are increasing, and impaired immunity is becoming more frequent.  New microorganisms will develop, and existing microorganism will develop even greater resistance. [28]


Hospital Infection Control Programs in the United States

Currently several organizations are involved in the setting of guidelines for infection control practices in the United States. The major non-governmental regulation agency is the Joint Commission on Accreditation of Healthcare Organizations (JCAHO), which act to survey and accredit hospital infection control programs across the country[29]. Federal infection control programs include branches of the Center for Disease Control (CDC) which has stated that several categories are considered important for the prevention of infection spread[30]. These components include a hospital-wide surveillance system, at least one full time infection control practitioner for every 250 hospital beds, programs that report back to the healthcare workers involved, and an effective infection control physician[31]. Besides the CDC there are other governmental agencies that have some involvement with infection control programs. The next part of this document will deal with providing a basic structure for infection control programs and an example of a successful infection control program.


The Infection Control Practitioner and Infection Control Committee


The Infection Control Committee

The infection control committee is a multi-disciplinary group of individuals who meet to discuss current surveillance data and to institute new programs or measures to ensure infection control. Within this committee, there is also a chairperson who is either a physician or an individual with a doctoral degree.[32] It is recommended that the chairperson should be trained in epidemiology. This is achieved by a program held with the Society for Healthcare Epidemiology of America in conjunction with the CDC[33]. However, if the chairperson cannot provide expert clinical and epidemiological consultation, another member(s) of the committee can aid the committee. This committee is also a forum for summarization and to solicit expert advice from the individuals on the panel. While the infection control committee is intimately involved with infection control within patient and employee populations it also reports to other administration within the hospital to allow for transparency within the proceedings and to use the expertise of others within the hospital administration.


The History of Infection Control Practitioner (ICP)

Nosocomial infections have been a major problem in the United States since the 1950s. The first steps in infection control was undertaken away from the US in England and it was in 1963 that Stanford University hired its first full time personnel to both document and control hospital acquired infections. In 1968, the Center of Disease Control (CDC) became involved and set up a course on surveillance, prevention, and control of nosocomial infections for ICPs and between 1970 and 1980, nearly all hospitals in the US had developed a formal infection control program and instituted an ICP[34].


The Role of the ICP

The ICP has several critical roles in infection control. First, the ICP is intimately involved in surveillance within the hospital. It is the role of the ICP to document comprehensively on recent outbreaks in the hospital, to follow up on the management of an outbreak, and calculate the distribution of outbreaks monthly[35].  The ICP also then compares the hospital outbreak information with the nationwide report on nosocomial infections, which is published by the National Nosocomial Infections Surveillence System (NNIS) of the CDC and current research based on trends in outbreaks[36]. The NNIS is the result of yearly reporting by 220 hospitals voluntarily to the CDC[37]. The ICP is also responsible for monitoring routes of transmission and the safety placements in place to control infection. That is, the ICP is responsible for sampling and testing of items such as dialysis water, infant formula, and equipment commonly associated with nosocomial infections. Also, the ICP is responsible for continual quality assessment and control. The ICP must continuously gather information on the quality of control, assess how well the current policies are working, and to use new projects and studies to parse out better ways to control infections within the hospital. Beyond the roles the ICP has in direct application to infection control, this individual must also be involved with the Infection Control Committee (ICC) within the hospital and to inform the committee on the infection control practices in the hospital and help the committee make a decision on changes that might effect the way infection control is run in the institution[38][39]. In the same vein as the ICP\x92s work in the ICC, this individual must also be aware of changes in federal regulations and to make sure that all current policies are up to date and on par with the current laws. And last but not least, the ICP is the main disseminator of information to the hospital\x92s staff. Education, along with surveillance, represents more than 50% of the work that the ICP does and is critically important for the control of infections[40].


Government Agencies and Infection Control

Several government entities are responsible for infection control in United States hospitals. The most well known is probably the Centers for Disease Control. Currently, the CDC\x92s National Center for Infectious Disease has a Hospital Infections Program (HIP) which acts both in a surveillance role and in coordinating control programs[41]. Part of the HIP\x92s work is the NNIS. The HIP is also responsible for the research in this field and providing some hospitals with the help they need to identify the infection and to do sampling and testing. Finally, the HIP publishes guidelines for hospitals to follow to control and prevent infections that are based on the results of studies undertaken by the HIP. Another division of the CDC that is involved with nosocomial infections is the National Institute for Occupational Safety and Health (NIOSH), which acts to determine occupation based illness and can have a role in influencing healthcare policies regarding employees in the health field and to decrease their risk or exposure to infection[42]. Other governmental agencies include the Hospital Infection Control Practices Advisory Committee (HICPAC) and Immunization Practices Advisory Committee (ACIP), both of these committees act as an advisory force for the CDC and its HIP program[43][44]. Finally, besides the main regulators of infection control there are many secondary programs that also have an important impact on infections prevention and control, they are:


A.                           The Food and Drug Administration (FDA) is also responsible for the safety of not only drugs but blood and blood products, and medical and radiologic devices. The FDA is the main regulator of blood supply safety, which can be a site for infection spread[45].

B.                           The National Institutes of Health is a large organization with a lot of funds and resources available. This system is one of the greatest contributors to research on the cause, prevention, and treatment of infectious diseases. This can reflect then positively on the control of nosocomial infections and the prevention of such infections[46].

C.                           The Health Care Financing Administration (HCFA) is mainly responsible for oversight of the Medicaid and Medicare programs. However, the HCFA also has regulations on upkeep of hospitals according to governmental guidelines and they even have their own set of rule for infection control and prevention in the hospital or long-term care setting[47].

D.                           The Environmental Protection Agency also plays a role in infection control as it regulates pesticides, air and water pollution, and solid waste[48]. This is important since a number of nosocomial infections are the result of environmental factors, making the proper disposal of medical wastes essential for prevention of infection.

E.                            The Occupational Safety and Health Administration (OSHA) has a similar role as the NIOSH and protects the health of workers in the healthcare field[49].


While the Joint Commission on Accreditation of Healthcare Organizations is not a governmental agency, it is closely tied with regulation in all US hospitals. The JCAHO continuously publishes goals and standards for achievement in hospitals[50]. This group also undertakes extensive review of infection control programs in hospitals every three years.


Specific Infection Control Measures

Besides the committees and other leaders in infection control, much of infection control lies in the hands of the personnel in direct contact with the sick patient. These healthcare employees must understand specific guidelines in prevention of infection transmission through isolation and other good healthcare habits. Much of this information in disseminated through training and educational programs given by the infection control departments. An example of guidelines that are essential for the healthcare worker are specified as:


Hand Washing

Though simple, this measure is one of the most effective methods in prevention of the spread of infection. Depending on the type of care being provided there is a different hand-washing protocol indicates. For example, with routine care in the hospital, healthcare workers can wash with a non-antiseptic soup or to disinfect the hand by rubbing with an alcohol solution[51]. However, when caring for patients who are already suffering infection, hands must be washed with antiseptic soap for at least one minute or hands can be disinfected by rubbing with alcohol solution[52]. Finally, in the surgical setting, the hand and forearm must be washed with an antiseptic soap for 3 to 5 minutes or simple hand washing with the addition of disinfection by rubbing on alcohol[53].


Hygiene and Uniform

Healthcare workers must also be conscious of their personal hygiene and what they wear to work as it could help spread infection within the hospital. For example, employees must have good personal hygiene, maintain short and clean nails, and keep hair worn short or pinned up[54]. Also, employees should wear a uniform that is covered by a white coat and must obey special uniform rules in setting such as burn or intensive care units[55]. Clothing must also be easy to decontaminate and cleaned daily to keep at optimum conditions. It is important that with any exposure to a possible pathogen, clothing should be changed as soon as possible[56]. Shoes are another measure of safety in the healthcare system. Staff should wear shoes that are dedicated to the particular unit and make sure that the shoes have been cleaned.


Barriers: Caps, Masks, Gloves

Another important group of precautions to prevent the spread of infection is the use of barriers such as caps, masks, and gloves. In general, caps are suggested when in aseptic units, operating rooms, or when performing other invasive procedures. Masks that are made of synthetic material that can filter the air are considered good barriers against microorganisms[57]. Masks made of other material such as wool, gauze, or paper are not considered effective. The use of masks is indicated for many situations and is present for both the protection of the patient and the healthcare worker.  Gloves are another set of necessary barrier when working with patients with a communicable disease. Staff should wear non-sterile gloves when caring for this type of patient while when working in surgery or immuno-compromised patients, gloves used should be sterile[58]. Again, gloves are used for protection of both the patient and healthcare provider.


Injection Practices

Transmission of blood borne pathogens are often the result of unsafe injection methods. It is recommended that all staff are aware that they should decrease unnecessary injections, to always use a sterile needle and syringe, and to dispose of the used needle and syringe in an appropriate manner, i.e. the use of a sharps container and biohazard disposals[59].


Equipment Safety

Another common mode of transmission of infection is through equipment and environmental causes. Though it may appeal to common sense, it is necessary that the hospital environment is thoroughly cleaned often. The hospital can be divided into four zones where different cleaning procedures can be followed. In zone A, there are no patients in this area and normal cleaning can be used. In zone B, patients are present but do not have an infection nor are susceptible to infection. Zone B should be cleaned in a manner that does not raise dust and a detergent solution may be used to improve the cleaning. In zone C, patients are infected and isolated and in zone D, patients are often highly susceptible to infection and are isolated[60]. These areas must be cleaned with a detergent or antiseptic solution and different cleaning equipment must be used for different rooms.  Another important way to keep the equipment and environment safe is to disinfect through the use of other compounds than those used for cleaning. These compounds are usually non-volatile, remain safe for the patient and staff, and should be effective for a short time frame. Disinfection can be categorized as high, intermediate, or low. Under high-level disinfection, all microorganisms should be eliminated with the exception of heavy bacterial spore counts. Under intermediate disinfection, most bacteria and viruses are killed but not all spores are killed. Finally, in low-level disinfection, only some microorganisms are killed with some more resistant species escaping destruction[61]. One last way to ensure equipment safety is sterilization, which is destruction of all microorganisms. Sterilization can be achieved through both mechanical and chemical processes[62]. While equipment and device disinfection and sterilization is critical, it is also crucial that all personnel are trained properly in the use of the equipment and device and know contacts for any malfunctions in such equipment.



While all of the infection control methods deal with physical objects, isolation of the patient also plays a critical role in infection control. The isolation of an infected patient can often prevent the spread of disease and also protect the patient from acquisition of other infections[63]. Isolation policy may vary slightly between hospitals but patient are usually evaluated before being placed under isolation.


Surveillance and Infection Control

Surveillance has been instituted for many years since the rise of nosocomial infections in the United States. A majority of hospitals have their own surveillance systems and some hospitals voluntarily report their findings to the CDC and the NNIS report is written to give other hospitals an idea of how well their infection control systems are working. Surveillance within the hospital can be gathered in several ways, they are:


Hospital-wide Surveillance

This is an exhaustive method that keeps track of every patient and almost all outbreaks are detected very early. This type of surveillance also records different types of infections and may help the healthcare worker to clearly identify the clusters of infection and to formulate a plan to deal with an emerging infection[64][65]. However, this approach is usually very labor-intensive and costly as it requires meticulous data gathering.


Surveillance by Objective/Priority-Directed Surveillance

This approach to surveillance is becoming more common for most hospitals and is a priorities-based approach to data gathering. That is, the hospital determines which diseases or infections are of particular importance to them and those are the ones that have extensive information gathered about them. The determination of which infections to follow most closely could be based on severity of disease, total mortality/morbidity of the disease, frequency of the infection, length of stay, and cost of treating the infection[66]. However, with this type of approach, there is a less broad coverage of data and certain disease clusters may be missed by the surveillance team.


Targeted Surveillance

Similar to objective-based surveillance, targeted surveillance gather data based on the site, unit, outbreak, or in a rotating manner. In site-based, data is gathered based on which types of sites the infection occurred at, such as a surgical site or different organ systems[67]. Unit-based surveillance measures more high risk areas and may target a certain problem area in the hospital for education and follow up[68]. Unit-specific surveillance may help to identify infection control personnel that require more training. Rotating surveillance is to study a particular unit periodically[69]. This type of surveillance is time efficient and cost-effective but can also lead to missing of clusters of disease. Finally, outbreak based surveillance is targeted just to specific outbreaks in a certain period of time[70]. This approach should always be combined with other approaches as they do not provide a general view of infection control in the hospital.


Infection Control Case Study: The Cleveland Clinic Foundation[71][72]

Accredited by the JCAHO, the Cleveland Clinic Foundation (CCF) is one of the major hospital systems within the Cleveland, Ohio area. Besides a main campus, CCF also has numerous regional hospitals and outpatient clinics. In the main campus, the hospital has about 1008 beds and employs a large infection control department, which not only is involved with the main campus but also coordinates with all regional facilities. The mission of the infection control program is to \x93reduce the risk and incidence of health care acquired infections.\x94 They also note that \x93infection prevention and control is an integrated and collaborative process throughout the entire organization.\x94 The organization of the infection control program at CCF-main campus can be summarized as follows:

The Department of Infection Control and Epidemiology is under the umbrella of two divisions: the Division of Nursing and the Division of Medicine. The Division of Nursing is responsible for leadership, fiscal support, and administrative services. The Division of Medicine also shares responsibility with leadership and provides both technical and clinical direction. This department also has support and collaboration with other departments in CCF like Patient Support, Environmental Health and Safety, Center for Corporate Health, Occupational Health, Division of Laboratory Medicine, and Office of Quality Management.



Members of the Department of Infection Control and Epidemiology include four full-time and two part-time nurse epidemiologists who act as ICPs for the program. These are individuals who have training as a registered nurse and are certified by the Certification Board of Infection Control and Epidemiology. Each of these ICPs is responsible for different departments and nursing units within CCF depending on their areas of interest and expertise.


Infection Control Committee

The Infection Control Committee at CCF is chaired by the Hospital Epidemiologist and comprises of a multidisciplinary group of individuals that oversee the infection prevention and control programs. This committee is responsible for evaluating infection prevention measures, oversee changes in programs, law, and regulations, and review new guidelines and surveillance. The ICC reports directly to the Medical Staff Committee in CCF and frequently addresses administration concerns during ICC meetings. The ICC meets with planned agenda three times a year. Their meeting minutes are made available to relevant department and professional leaders.


The members of the ICC at CCF:

1. The Hospital Epidemiologist (Chair)

2. Associate Hospital Epidemiologist(s)

3. Clinical Department Representatives

a. Medicine

b. Surgery

c. Anesthesia

d. Laboratory Medicine (Microbiology)

e. Occupational Health

f. Pediatrics

g. Infectious Disease

h. House staff

4. Infection Control Practitioners

5. Nursing Quality Management - ad hoc

6. Nursing Administration - ad hoc

7. Intensive Care

8. Administration

9. Ad hoc Departments (Central Service, Environmental Services, Textile Services, Nutrition Services, Facilities Engineering, Pharmacy, Environmental Health and Safety, Materials Management, Operating Room, and Regional Medical Practice; to attend meetings when necessary and/or serve as consultants).


A smaller, more focused Executive Committee of the Infection Control Committee meets weekly to discuss day to day changes and concerns and to institute changes in outbreak management and infection control. Any major decisions or changes by the executive committee are brought forth to the complete ICC for consideration.


The Executive Committee membership includes:

1. Chairman of Infection Control Committee (Hospital Epidemiologist)

2. Associate Hospital Epidemiologist(s)

3. Infection Control Practitioners

4. Nursing Administration

5. Invited guests ad hoc


Infection Control, Prevention, and Surveillance

The major infection control and prevention measures used by CCF can be defined by the following points:

1.      Hand hygiene

2.      Use of barriers for contact with body substances such as blood

3.      Extensive programs for specific infections \x96 focusing on transmission and precautions based on the organism

4.      Equipment and Medical Device Safety

5.      Health Screening of Employees and Immunization of employees and volunteers

6.      Post-Infection and Infection counseling and prophylactic treatment of employees and volunteers

7.      Reduce risk of animal infections brought into the hospital. It should be noted that CCF is also a research institution with animal studies.


Surveillance is another important aspect of infection prevention and control at CCF. Overall, surveillance is an on-going process based on systematic observation and documentation of all incidences of hospital acquired infections. A majority of surveillance however is based on the targeted and priority-directed approaches. That is, there is continuous surveillance in specific infections in certain units and surveillance of procedures associated with significant morbidity and mortality.  The results from the surveillance is used both internally within departments to look for trends and affect change and all reportable disease are also reported to the Ohio Department of Health.


Outbreak Management

In the case of an outbreak the chain of action by CCF is:

            1. Confirm that an outbreak exists

2. Establish or verify diagnosis of reported cases; identify agent

3. Search for additional cases; collect critical data and specimens

4. Characterize the cases by person, place, and time

5. Formulate tentative hypothesis (make the best guess to explain the observations

6. Test hypothesis

7. Consider control measures alternative - institute most appropriate

8. Evaluate efficacy of control measures

9. Communicate findings to Infection Control Committee and submit report to office of Quality Management Ad hoc working groups will be formulated to respond to perceived outbreaks or problems. The hospital epidemiologist and infection control practitioners select ad hoc members based on the pathogens or problems identified or as need determines.


Finally, the department of infection control and epidemiology at CCF is also involved with special situations and programs not directly linked to a particular unit within the hospitals. This department also monitors the following:

1.      Continuous education of both new and current employees

2.      Construction activity

3.      Research in infection control



            Nosocomial infections continue to be a burden to the American healthcare system through increased risks to patients and employees.  These infections have tremendous health and financial costs with an estimated incidence of 2,000,000 infections per year, 20,000 deaths per year, and added costs of 2 billion per year.  Effective infection control programs are essential to controlling and preventing nosocomial infections.  These programs include a core of the infection control committee, infection control practitioner, and individual employee actions.  Thus, it is important that we seek to continually improve existing infection control policies and programs.





  1. Bolyard, EA, Tablan, OC, Williams, WW, Pearson, ML, Shapiro, CN, and Deitchman, SD. The Hospital Infection Control Practices Advisory Committee: Guideline for infection control in healthcare personnel. 1998
  2. Coffin SE and Zaoutis TE. Infection Control, Hospital Epidemiology, and Patient Safety. Infect Dis Clin N Am 19 (2005) 647-665
  3. Department of Infection Control and Epidemiology at Cleveland Clinic Foundation: Mission Statement and Infection Control Program \x96 available within the Cleveland Clinic Foundation Intranet or through the Department.
  4. Ducel, G., Fabry, J., and L. Nicolle, \x93Prevention of hospital acquired infections: A Practical Guide, 2nd Edition,\x94 World Health Organization 2002.                    
  5. Gordis, Leon, \x93Epidemiology, Third Edition,\x94 Elsevier Saunders 2004.
  13. Personal Correspondence with ICP at the Cleveland Clinic Foundation
  14. Wenzel, RP. Prevention and Control of Nosocomial Infections. 3rd Ed. Williams and Wilkins, 1997.


Additional Sources:


[1] Ducel, G., Fabry, J., and L. Nicolle, \x93Prevention of hospital acquired infections: A Practical Guide, 2nd Edition,\x94 World Health Organization 2002.

[2] Ducel, 4

[3] Gordis, Leon, \x93Epidemiology, Third Edition,\x94 Elsevier Saunders 2004.

[4] Ducel, 4

[5] Ducel, 2

[6] Ducel, 2-3

[7] Ducel, 3

[8] Ducel, 5

[9] Ducel, 5

[11] Ducel, 5

[12] Ducel, 6

[14] Ducel, 6-7

[15] Ducel, 7

[16] Ducel, 7

[17] Ducel, 7

[18] Ducel, 57

[19] Ducel, 57

[20] Ducel, 58

[21] Ducel, 58-59

[22] Ducel, 59

[23] Ducel, 59-60

[28] Ducel, 4


[30] Wenzel, 57-58


[32] Wenzel, 33-40

[33] Wenzel, 33-40

[34] Wenzel, 33-40

[35] Wenzel, 33-40


[37] Wenzel, 57-58

[38] Wenzel, 33-40

[39] Dept. of Infection Control and Epidemiology of CCF

[40] Wenzel, 33-40

[41] Wenzel, 57-67

[42] Wenzel, 57-67

[43] Wenzel, 57-67

[44] Bolyard

[45] Wenzel, 57-67

[46] Wenzel, 57-67

[47] Wenzel, 57-67

[48] Wenzel, 57-67

[49] Wenzel, 57-67


[51] Ducel, 30-31

[52] Ducel, 30-31

[53] Ducel, 30-31

[54] Ducel, 32

[55] Ducel, 32

[56] Ducel, 32

[57] Ducel, 33

[58] Ducel, 33

[59] Ducel, 33

[60] Ducel, 33-34

[61] Ducel, 33-34

[62] Ducel, 33-34

[63] Wenzel, 75

[64] Coffin, et al.

[65] Wenzel, 127-153

[66] Wenzel, 127-153

[67] Wenzel, 127-153

[68] Wenzel, 127-153

[69] Wenzel, 127-153

[70] Wenzel, 127-153

[71] Personal Correspondence with CCF ICP

[72] Dept. of Infection Control and Epidemiology of CCF