Principles of infection control in long-term care facilities

INTRODUCTION — Long-term care facilities (LTCFs) represent a diverse group of health care settings that serve individuals of all ages and provide variable degrees of care; LTCFs are increasingly addressing a broader range of acute care needs. LTCFs include nursing homes, skilled-nursing facilities providing postacute care, assisted living facilities, retirement homes, rehabilitation centers, long-term care hospitals, long-term psychiatric facilities, and institutions for individuals with intellectual disabilities. For many residents, these facilities are a home as well as a place of nursing, medical, and/or psychosocial care.

The Association for Practitioners in Infection Control and the Society for Hospital Epidemiology have developed guidelines for infection prevention and control in LTCFs [1].

Staffing and support for infection control in LTCFs lag behind infection control programs in acute care hospitals [2-6]. Challenges to infection control in LTCFs include high resident-staff ratios, high staff turnover, and inadequate implementation of infection control policies [1].

General issues related to infection prevention and control in LTCFs will be reviewed here. Additional information on infection control specific to COVID-19 and causes of infection in LTCFs are discussed separately. (See "COVID-19: Infection prevention for persons with SARS-CoV-2 infection" and "Causes of infection in long-term care facilities: An overview".)

EPIDEMIOLOGY — In the United States, the population age 65 years and over increased from 37.2 million in 2006 to 49.2 million in 2016 (a 33 percent increase) and is projected to almost double to 98 million in 2060 [7]. A relatively small number of those (1.2 million) lived in nursing homes in 2016. However, the percentage of nursing home residents per population increases dramatically with age, ranging from 1 percent for persons age 65 to 74 to 3 percent for persons age 75 to 84 and 9 percent for persons age 85 and over.

The incidence of hospital-acquired infections in LTCFs is comparable with that in acute care hospitals and ranges from 1.8 to 13.5 infections per 1000 resident-days [1,8]. A point prevalence study of over 1000 LTCFs in 19 European countries reported that 3.4 percent of nursing home residents had a health care-associated infection (HAI) when evaluated on a single day in 2013 [9]. The prevalence rate in individual countries ranged from 0.4 to 7 percent.

Infections contribute to 63 percent of deaths in LTCFs and are the primary reason for 25 to 50 percent of transfers to acute care hospitals [10]. The most common infections are urinary tract infection (3.0 to 5.2 percent), pneumonia (2.2 to 4.4 percent), and cellulitis (1.6 to 2.0 percent) [11]. Discussion of specific infections in LTCF residents is found elsewhere. (See "Causes of infection in long-term care facilities: An overview".)

Residents of LTCFs are at risk for infections circulating in the community as well as health care-associated infections. Risk factors for infection include:

●Underlying medical illness

●Use of medications that suppress the immune system or the central nervous system

●Factors promoting person-to-person transmission such as close living quarters and sharing of meals

●Depressed mental state

●Protracted use of devices such as urinary catheters and nasogastric tubes

●Incontinence

Multidrug-resistant organisms (MDROs; methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, and multidrug-resistant gram-negative bacteria) are increasingly important causes of colonization and infection in LTCFs. Tools for control include standard and isolation precautions as well as antimicrobial stewardship. (See 'Standard precautions' below and 'Antimicrobial stewardship' below.)

ELEMENTS OF INFECTION CONTROL — LTCFs should have a designated infection control practitioner and multidisciplinary oversight group (including facility administrator, medical director, clinical staff, and local health department). Other important components of infection control include written infection control policies (including those related to environmental cleaning) and procedures as well as protocols for detecting, treating, containing, and preventing transmission of potential pathogens. Infection control programs for LTCFs should be tailored to the type of facility, the layout of the facility (including isolation facilities and adequate availability of sinks for handwashing), the risk factors among the residents, and available resources.

Surveillance for infection — Surveillance is important for detection of outbreaks, changes in infection rates, and other issues requiring infection control intervention (including the need for additional training or staff education) [12,13]. The components of a surveillance system include a mechanism for data collection, a schedule and procedure for evaluation of data, dissemination of results, and mechanisms for action and follow-up. Monitoring of disease patterns over time may provide information on the effectiveness of changes in infection control practices and policies.

The scope of surveillance depends on the type of facility and available resources. Facility-wide surveillance provides information on the burden of infection and detects outbreaks, whereas targeted surveillance focuses on preventable infections with significant morbidity, requires fewer resources than facility-wide surveillance, and can be used to monitor targeted interventions to improve resident safety. Each facility should have a specific surveillance plan that includes the type of surveillance to be undertaken, the form of data collection, and the frequency of data reporting.

Surveillance data can be collected via periodic review of charts, laboratory reports, and other records. In addition, regular conversations with nursing staff and residents and clinical observations are important components of surveillance data collection [1,14]. Surveillance of adherence to infection control measures (such as hand hygiene compliance, catheter care, and employee and resident immunization rates) is also an important component of infection control. (See 'Prevention of infection' below.)

The frequency of data review depends upon the size and the nature of the facility. Larger facilities should examine data at least weekly, while smaller facilities can use a biweekly or monthly interval. As an example, a facility managing residents on ventilators has substantially different needs for surveillance than one with residents predominantly with dementia. Data evaluation should include detection of sentinel events, such as identification of a resident with crusted scabies or detection of new diarrheal illness among residents of the same unit within one week. More subtle trends (such as an increase in respiratory tract infections) are best detected by comparisons with previous weeks or months. Information on trends should be provided back to units and employees, with plans for action and follow-up. (See "Causes of infection in long-term care facilities: An overview".)

Calculating crude infection rates (number of cases divided by resident census) is useful for identifying outbreaks within a facility, while calculation of risk-adjusted infection rates is most accurate for comparison of infection rates between facilities. It may be useful to express infection rates in terms of specific exposure (for example, calculation of infection associated with urinary catheter should use the number catheter-days) rather than an overall census denominator. One method for interfacility comparison of infection rates created a standardized regional data set to provide an external benchmark for interfacility comparisons [15].

Outbreaks may be defined as an unusual increase in illness above baseline levels; outbreak surveillance and control should be a high priority. Issues to be considered in an outbreak management plan include developing a case definition, case finding, analyzing the outbreak, formulating a hypothesis regarding transmission, and designing and evaluating control measures. The Society for Hospital Epidemiology guidelines may assist in creating an outbreak management plant [1].

Common causes of outbreaks in LTCFs include respiratory and gastrointestinal infections. In some instances, a single case may be sufficient to prompt an infection control response; examples include influenza, tuberculosis, meningococcal meningitis, Legionella infection, norovirus, salmonellosis, group A streptococcal soft tissue infection, viral hepatitis, scabies, and infection with antibiotic-resistant pathogens. In the setting of diarrhea, consideration of the likely cause should influence the infection control response; diarrhea associated with tube feeding requires care of an individual resident, while a cluster of residents with vomiting and diarrhea requires a vigorous infection control response for diagnosis and prevention. (See "Causes of infection in long-term care facilities: An overview".)

Prevention of infection — Effective implementation of preventive measures is critical for infection control in LTCFs. These include use of appropriate contact precautions in the setting of resident care, careful attention to hand hygiene, good environmental cleaning, administration of immunizations to residents, and antimicrobial stewardship [1].

Residents — At the time of admission, each resident should have a complete history, review of immunization history, and physical examination [1]. The three most important vaccines for older adult residents of LTCFs are influenza vaccine, pneumococcal vaccine, and tetanus-diphtheria toxoid vaccination [1,16].

●Influenza – Influenza vaccine is effective in older adult persons and should be given annually. (See "Seasonal influenza vaccination in adults".)

Higher vaccination rates among both residents and staff of LTCFs have been associated with lower rates of influenza outbreaks [17]. However, vaccines are known to be less effective in older individuals and those with comorbidities. Thus, other measures need to be implemented to decrease the likelihood of residents in LTCFs contracting influenza [18]. As an example, timely use of antiviral (eg, oseltamivir) prophylaxis may be important in abbreviating influenza outbreaks, especially in years of vaccine mismatch [19]. Use of any antiviral drugs halves the attack rates of influenza [20]. Commencing prophylaxis within two days of the onset of the outbreak was associated with keeping attack rates under 25 percent in a Taiwanese study [21]. Social distancing and personal protective equipment were not associated with a significant decrease in attack rates [20]. Details about the use of antivirals for prophylaxis are discussed elsewhere. (See "Seasonal influenza in adults: Role of antiviral prophylaxis for prevention".)

The development of guidelines on the prevention and control of influenza in LTCFs is difficult due to the variation in the facility size, resident characteristics, and resources available. The United States Centers for Disease Control and Prevention (CDC) has issued recommendations for prevention and control of influenza. In addition, the World Health Organization (WHO) has published a best-practice document to support managers of LTCFs [22].

●Pneumococcal pneumonia – Pneumococcal vaccine should be given at age 65 or on admission to the LTCF if the resident is over 65 years, unless the resident has been recently immunized. (See "Pneumococcal vaccination in adults".)

●Tetanus-diphtheria toxoid vaccination should be offered every 10 years. (See "Tetanus-diphtheria toxoid vaccination in adults".)

Issues related to tuberculosis screening are discussed separately. (See "Causes of infection in long-term care facilities: An overview", section on 'Tuberculosis'.)

Issues related to zoster vaccine are discussed separately. (See "Vaccination for the prevention of shingles (herpes zoster)".)

Issues related to chlorhexidine bathing are discussed separately. (See "Infection prevention: Precautions for preventing transmission of infection", section on 'Patient bathing'.)

The role of screening for colonization with drug-resistant organisms for residents in LTCFs has yet to be defined.

Health care workers — Health care workers in LTCFs should have an assessment of immunization status at the start of employment. Annual influenza vaccination for health care workers in LTCFs is particularly important [1]. Increased vaccination coverage among health care workers has been shown to reduce the probability of infection in residents of LTCFs [23]. Issues related to immunizations for health care workers are discussed separately. (See "Immunizations for health care providers".)

Training of health care workers is critical to effective infection control in LTCFs. Training should be formal and informal, sufficiently frequent to address needs arising from staff turnover, and should be readily understandable by all employees. Orientation for health care workers should include hand hygiene, modes of transmission of infection, assessment of residents for infection, and environmental cleaning. In addition, employees should report significant communicable symptoms (including cough, rash, or diarrhea) and should not have contact with residents while potentially infectious. Written procedures and guidelines should be developed addressing these topics.

Education on precautions to reduce the risk of transmission of bloodborne pathogens should be offered, and there should be an established mechanism for access to appropriate postexposure prophylaxis in the setting of bodily fluid exposure [1]. (See "Prevention of hepatitis B virus and hepatitis C virus infection among health care providers".)

Issues related to tuberculosis screening for health care workers are discussed separately. (See "Tuberculosis infection (latent tuberculosis) in adults: Approach to diagnosis (screening)".)

Visitors — Visitors to LTCFs are possible sources of infection for other residents, visitors, and staff. The CDC recommendations about management of visitor access include hand hygiene, use of personal protective equipment while visiting residents on precautions, and limited movement within the facility. Visitors with respiratory symptoms should be asked not to visit, but if visitation occurs, they should wear masks and avoid contact with other residents [24]. During an outbreak of transmissible infection (such as influenza), it may be prudent to restrict visitors [25].

Precautions

Standard precautions — Standard precautions that should be employed with all residents include hand hygiene, respiratory etiquette, safe injection practices, and use of gloves, gowns, masks, and/or eye protection if contact with mucous membranes, nonintact skin, or body fluids is anticipated.

Hand hygiene is the single most important infection control measure. Hand hygiene refers to either handwashing with soap and water or the use of alcohol-based gels or foams that do not require the use of water. Hand hygiene should be performed by staff and visitors before and after each contact with a resident or surroundings, before aseptic procedures, and after contact with blood or body fluids.

In an effort to contain the spread of multidrug-resistant organisms (MDROs) in nursing homes, the CDC recommends the use of personal protective equipment, not only when exposure to blood and body fluids is expected, but also during high-contact resident care activities (eg, dressing, bathing/showering) that provide opportunities for transfer of MDROs to staff's hands and clothing [26].

Isolation precautions — Transmission-based precautions (contact, droplet, and airborne) for certain pathogens are summarized in the table (table 1). Issues related to precautions are discussed further separately. (See "Infection prevention: Precautions for preventing transmission of infection".)

Some LTCFs lack private rooms or rooms with appropriate ventilation. Cohorting of residents with the same organisms is sometimes acceptable if single rooms are not available [1].

If adequate isolation facilities are not available and cohorting is not possible, transfer to an acute hospital may be warranted in some circumstances (such as in the setting of tuberculosis) [27].

Antimicrobial stewardship — Antimicrobial stewardship in LTCFs should be tailored to the facility and may include guidelines for antibiotic use in the setting of suspected urinary and respiratory tract infections, antimicrobial restrictions, audit and feedback on antimicrobial prescribing, and education for medical staff, nursing staff, residents, and family members [1,28-33]. The CDC has issued advice for antibiotic stewardship in LTCFs on its website.

Use of antibiotics in LTCFs is common [34,35]. In some circumstances, antibiotics are administered for inappropriate indications and for protracted periods; examples include urinary tract colonization associated with catheter use and pressure sores that are not infected [34-37]. Challenges to appropriate antibiotic prescribing in LTCFs include limited access to laboratory and radiograph support and off-site clinicians resulting in assessments based on phone call advice.

Bundled interventions — In certain circumstances, a "bundled" approach to addressing a particular infection control issue may be warranted in LTCFs, particularly in the setting of an outbreak. As an example, one investigation described a bundled intervention for reducing infection due to K. pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae [38]; interventions included screening for rectal colonization, contact isolation, daily chlorhexidine bathing, and health care worker education.

ADDITIONAL RESOURCES — The United States Centers for Disease Control and Prevention (CDC) website is a useful resource for infection control and antimicrobial stewardship fact sheets, articles, and presentations.

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Infection control".)

SUMMARY AND RECOMMENDATIONS

●Types of long-term care facilities – Long-term care facilities (LTCFs) include nursing homes, skilled-nursing facilities providing postacute care, assisted living facilities, retirement homes, rehabilitation centers, long-term care hospitals, long-term psychiatric facilities, and institutions for individuals with intellectual disabilities. (See 'Introduction' above.)

●Epidemiology – Residents of LTCFs are at risk for infections circulating in the community as well as health care-associated infections. (See 'Epidemiology' above.)

●Components of an infection control program – LTCFs should have a designated infection control practitioner and multidisciplinary oversight group (including facility administrator, medical director, clinical staff, and local health department). Other important components of infection control include written infection control policies and procedures as well as protocols for detecting, treating, containing, and preventing transmission of potential pathogens. (See 'Elements of infection control' above.)

●Surveillance – Surveillance is important for detection of outbreaks, changes in infection rates, and other issues requiring infection control intervention. The components of a surveillance system include a mechanism for data collection, a schedule and procedure for evaluation of data, dissemination of results, and mechanisms for action and follow-up. (See 'Surveillance for infection' above.)

●Infection control interventions – Effective implementation of preventive measures is critical for infection control in LTCFs. These include use of appropriate precautions in the setting of resident care, careful attention to hand hygiene, administration of immunizations to residents, and antimicrobial stewardship. (See 'Prevention of infection' above.)

●Staff training – Training of health care workers is critical to effective infection control in LTCFs. Orientation for health care workers should include issues related to hand hygiene, modes of transmission of infection, assessment of residents for infection, and immunization for prevention of communicable diseases. (See 'Health care workers' above.)

ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges Rhonda L Stuart, MBBS, FRACP, PhD, who contributed to an earlier version of this topic review.