Version July 2025
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 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.
This topic will discuss outbreak detection and management in LTCFs [1-4].
The basic principles of infection prevention and control (IPC) in LTCFs are discussed elsewhere. (See "Principles of infection prevention and control in long-term care facilities".)
Medical management of patients with suspected infections in LTCFs is discussed separately. (See "Medical care in skilled nursing facilities (SNFs) in the United States", section on 'Infections'.)
Topic reviews specific to coronavirus disease 2019 (COVID-19) are presented separately. (See "COVID-19: Epidemiology, virology, and prevention" and "COVID-19: Clinical features" and "COVID-19: Diagnosis" and "COVID-19: Infection prevention for persons with SARS-CoV-2 infection".)
SOURCES OF INFECTION —
Infections are common in residents of LTCFs, especially including respiratory tract infection, gastrointestinal infection, urinary tract infection, and skin and soft tissue infection [5]. Together, these infections represent 94 percent of infections seen in LTCFs [2,3,6,7]. (See "Medical care in skilled nursing facilities (SNFs) in the United States", section on 'Infections'.)
Some types of infection occur within individual patients and do not spread to other patients or cause outbreaks (eg, urinary tract infection, most types of bacterial pneumonia). However, some infections are caused by communicable pathogens, meaning they are capable of transmission from person to person. Certain pathogens can persist for long periods on surfaces or fomites and spread when individuals touch the contaminated item.
Some pathogens that cause outbreaks in LTCFs, especially respiratory viruses, are introduced to the facility from individuals who enter the facility from the community (ie, staff, visitors, or newly admitted residents). Less commonly, pathogens can arise from facility sources (eg, Legionella from water sources) or contaminated food or equipment.
SPREAD OF INFECTION —
LTCFs have unique features that support the transmission of infections and predispose them to outbreaks. Specifically, the patient population is at especially high risk for developing infection, and the environment provides ample opportunity for spread.
Patient-specific factors — Residents of LTCFs are at higher risk of developing infection after exposure due to their underlying conditions and medical interventions. Specific risk factors include the following:
●Underlying medical illness
●Incontinence
●Depressed mental state
●Use of medications that suppress the immune system or the central nervous system
●Protracted use of devices such as urinary catheters and nasogastric tubes
Facility-related factors — LTCFs are prone to spread infection due to numerous challenges unique to their environment:
●Communal living (including sharing of sanitary bathrooms)
●Frequent close contact between residents, staff, and visitors
●Frequent transfer of patients between health care facilities, including hospitals [8]
●High resident-staff ratios as well as high staff workload and turnover
●Inadequate implementation of infection prevention and control (IPC) policies
PREVENTION OF OUTBREAKS —
Preventing transmission of infection is one of the key pillars of IPC programs within health care facilities, including LTCFs.
The components of an effective infection prevention program are discussed in detail separately. (See "Principles of infection prevention and control in long-term care facilities".)
Not only do these programs prevent infections within LTCFs, but they also prevent spread of infection from LTCFs to the community and hospitals when residents, staff, and visitors leave the LTCF.
DETECTION OF OUTBREAKS —
An outbreak is defined as an unusual, significant increase in illness above the facility's baseline levels. In many cases, an outbreak is detected by care providers within the facility who notice a cluster of similar illnesses over a short period of time. A change in baseline surveillance data can also provide awareness of an outbreak; surveillance data can be especially helpful for detecting outbreaks when spread is more subtle and occurs over weeks or months.
A cluster of febrile illnesses, respiratory infections, vomiting and/or diarrheal illnesses, or rashes should raise suspicion for an outbreak. Detection of an epidemiologic link (ie, a common exposure or source) between cases further supports the diagnosis of an outbreak as opposed to an unexplained cluster.
For some infections, a single case of health care-acquired infection represents a sentinel event that should be investigated by infection prevention and control (IPC) personnel. An understanding of the incubation period for each illness can help to determine whether the infection was acquired during the health care facility stay or was incubating at the time of admission. Examples of sentinel events include single cases of crusted scabies, legionellosis, invasive group A streptococcal (GAS) infection, influenza, tuberculosis (TB), meningococcal meningitis, bacterial foodborne infection (eg, salmonellosis), bloodborne pathogen (human immunodeficiency virus [HIV], hepatitis B or C), and Candida auris.
If an outbreak is suspected, testing of affected residents should be performed to determine the underlying pathogen. In some cases, the local health department can provide testing and guidance.
MANAGEMENT OF OUTBREAKS
General approach — The approach to managing an outbreak in an LTCF involves early identification of all infected or colonized residents, prompt containment of the infection, and interventions to prevent spread. Outbreaks of respiratory pathogens are managed slightly differently than those due to pathogens that spread by direct or indirect contact or via a common source. (See 'Respiratory pathogens' below and 'Pathogens spread by contact' below.)
Overarching interventions include the following:
●Notification of local public health department – Local public health experts can help identify and manage outbreaks in LTCFs. In some of these locales, public health notification is mandatory for certain types of outbreaks.
●Development of a case definition and identifying affected individuals – A case definition is used to classify each resident (and staff member, if indicated) as part of the outbreak or not. Cases are often categorized based on the certainty of involvement in the outbreak (eg, definite case versus probable case).
Depending on the pathogen, the case definition may include only those who are symptomatic. In other situations, mass testing may be necessary to identify asymptomatic individuals who are colonized or subclinically infected with the pathogen.
●Determination of containment measures – Potential containment measures may include isolation of infected residents, cohorting of infected residents, quarantining exposed residents, and furloughing exposed staff.
•Isolation – Isolation involves physically isolating infected residents in private rooms (or housing them in a room with other infected residents), with a designated bathroom if possible, as well as use of transmission-based precautions depending on the pathogen. Some respiratory pathogens require use of a respirator (eg, N95), whereas others require only a well-fitting mask (eg, surgical mask). (See 'Respiratory pathogens' below and 'Pathogens spread by contact' below.)
•Cohorting – Cohorting involves placing residents infected with the same pathogen in shared space. This may include sharing rooms or dedicating a section or ward of the LTCF to infected residents. In such situations, dedicated trained staff may be assigned to these areas to prevent spread between infected and uninfected units.
•Quarantining – Quarantine is isolation of individuals (residents and staff) who have been exposed to the pathogen and are in the incubation period (ie, they may have acquired the infection but still be asymptomatic). Some pathogens are transmissible prior to onset of symptoms (eg, varicella, COVID-19). Some pathogens can be transmitted to others from colonized or infected individuals who never develop symptoms (eg, group A Streptococcus [GAS], methicillin-resistant Staphylococcus aureus [MRSA]).
•Furloughing – Staff members who are infected or have been exposed can be furloughed (instructed to not report to work until they are deemed noninfectious).
●Prevention of further spread
•Addressing the route of transmission – Each pathogen can be categorized based on the route of transmission.
Preventing spread of respiratory pathogens may involve masking of uninfected residents and staff as well as addressing ventilation issues within the facility.
Preventing spread of nonrespiratory and certain respiratory pathogens may involve extensive environmental cleaning and expanded use of gowning and gloving.
Regardless of the route of transmission, standard infection prevention and control (IPC) precautions should be optimized (eg, hand hygiene).
•Treating infected residents and staff – Providing treatment to infected residents and staff prevents further spread of infection and may shorten the period infected residents remain in isolation and staff remain away from work.
•Providing prophylaxis and/or vaccination – For some pathogens, prophylaxis with an antimicrobial (eg, antiviral agent) has been shown to reduce the duration of outbreaks and number of involved residents. Prophylaxis may be provided only to exposed residents and staff or to the entire affected area of the facility.
For many outbreaks, vaccination of residents and staff after the onset of an outbreak does not provide rapid enough immunity to abort the outbreak. However, for certain pathogens, vaccination is effective, particularly for outbreaks that are prolonged in nature. Vaccination has the added benefit of preventing future outbreaks caused by the same pathogen.
•Restricting visitors – Visitors may be the source of infection or may acquire the infection within the facility and spread it into the community.
Visitor restriction may involve limiting the flow of the visitors within the facility to specific areas or restricting visitation altogether.
●Preventing spread to other facilities – Transferring patients between facilities can lead to outbreaks in the receiving facility. If a resident is to be transferred, the receiving facility or service should be informed about the outbreak, regardless of whether the resident being transferred is identified as a case.
Respiratory pathogens — Numerous pathogens, especially respiratory viruses, can cause outbreaks characterized by rapid spread, large numbers of infected residents and staff, and severe illness. Respiratory viruses should be suspected if a cluster occurs of febrile illness with nonproductive cough or shortness of breath with or without myalgia, headache, or nasal congestion. Symptoms of acute respiratory infections are often similar, regardless of the pathogen [9].
For respiratory pathogens, the overall approach to management is similar, but there are some differences among pathogens. (See 'General approach' above.)
Testing all symptomatic patients is imperative to identify the suspected pathogen and to ensure that different pathogens are not circulating at the same time within the facility. For example, coinfections and outbreaks due to influenza and SARS-CoV-2 have been documented [10].
SARS-CoV-2 — COVID-19 caused many outbreaks in LTCFs during the peak of the pandemic and continues to cause outbreaks within facilities. During large community outbreaks, more than 40 percent of COVID-19-related deaths were linked to LTCFs, with figures as high as 80 percent in some resource-abundant countries [11].
The United States Centers for Disease Control and Prevention (CDC) and public health organizations in other countries have issued guidance on management of SARS-CoV-2 outbreaks in health care facilities, including LTCFs [12-16]. This guidance includes the interventions discussed above as well as specific interventions discussed separately. (See 'General approach' above and "COVID-19: General approach to infection prevention in the health care setting".)
During periods of high levels of community transmission, certain measures may be implemented to prevent introduction and spread of COVID-19, including visitor restrictions, universal masking, and screening staff members for symptoms prior to entering the facility [12,17-19].
Influenza — Influenza virus is typically brought into an LTCF by staff or visitors and spreads rapidly among the residents who share rooms and eat in a communal dining room. Seasonal outbreaks affecting residents and staff are common and are associated with substantial morbidity.
The challenges of preventing and controlling influenza outbreaks in these settings are well recognized. In a review of 49 outbreaks, median attack rates were 33 percent in residents and 23 percent in staff [20-22]. Attack rates may be up to 70 percent, and case fatality rates may be more than 10 percent [23]. (See "Seasonal influenza in adults: Clinical manifestations and diagnosis", section on 'Uncomplicated illness'.)
Older adults may have less typical presentations of influenza, and this limits the opportunities for early recognition and treatment [23]. In addition, increased age is a recognized risk factor for serious infection [22]. Having low threshold criteria to trigger testing with rapid diagnostic tests may reduce hospitalization and hospital length of stay [24]. The diagnosis of influenza is discussed separately. (See "Seasonal influenza in adults: Clinical manifestations and diagnosis".)
In addition to the above-described interventions (see 'General approach' above), antiviral prophylaxis (often with oseltamivir) is an important component of management of influenza outbreaks; prophylaxis may be especially important in years of vaccine mismatch [25,26]. Use of antiviral drugs significantly reduces the attack rates of influenza [20,27-30]. Details about the use of antivirals for prophylaxis are discussed elsewhere (table 1). (See "Seasonal influenza in adults: Role of antiviral prophylaxis for prevention".)
Further details of infection prevention and outbreak management of influenza in health care facilities are found separately. (See "Infection control measures for prevention of seasonal influenza".)
Respiratory syncytial virus and other viruses — Respiratory syncytial virus (RSV) can cause severe respiratory illness in patients who are older adults or have significant comorbidities [31]. In a series of hospitalized patients over 60, 18 percent had severe outcomes and 4.7 percent died. Seventeen percent of these cases were in LTCFs. (See "Respiratory syncytial virus infection in adults".)
RSV outbreaks in LTCFs are less common than SARS-CoV-2 or influenza outbreaks. If a respiratory virus outbreak is suspected but SARS-CoV-2 and influenza testing are negative, consideration of additional viral testing, including RSV, should be considered [10].
IPC interventions have been developed, and a vaccine is now available against RSV for adults at higher risk of severe disease, including individuals in LTCFs. (See "Respiratory syncytial virus infection in adults", section on 'Infection control precautions' and "Respiratory syncytial virus infection in adults", section on 'Vaccination'.)
Other viruses known to cause outbreaks in LTCFs include rhinovirus [32]. In a Canadian surveillance study, rhinovirus caused 59 percent of respiratory outbreaks during a six-month period in 2009, and disease was sometimes severe [32].
Legionella — Legionella spp can cause severe bacterial pneumonia with a high mortality rate in patients with comorbidities or older age. (See "Clinical manifestations and diagnosis of Legionella infection".)
A single case of infection due to health care-acquired Legionella spp should prompt investigation in health care facilities, including LTCFs. In many locales, public health officials require notification to allow prompt investigation of the source of infection, which is usually a contaminated water source. (See "Treatment and prevention of Legionella infection", section on 'Prevention of Legionella infections'.)
Most cases of legionellosis in LTCFs or hospitals originate from the facilities' water supply or plumbing, including ice machines. An outbreak within an LTCF in the United States was traced to a local cooling tower that likely dispersed water droplets into the LTCF through the air intake system or open windows [33].
Tuberculosis — Tuberculosis (TB) is known to spread in LTCFs, and infections are more likely to occur in regions with high community rates of TB.
Prevention of TB spread in LTCFs depends primarily on testing for latent TB in residents with past exposure or comorbidities that predispose to reactivation of latent TB. Universal screening for latent TB among individuals in LTCFs was common in the past, but targeted screening now has more support [34-37]. The indications and approach for latent TB infection (LTBI) testing are discussed separately. (See "Tuberculosis infection (latent tuberculosis) in adults: Approach to diagnosis (screening)".)
If an individual with active pulmonary TB is identified in an LTCF or other health care facility, specific interventions are necessary to prevent spread, including isolation in an airborne isolation room, use of respirators for staff who enter the room, screening of exposed individuals, and prophylaxis for a subset of close contacts. Public health officials should be notified for further guidance and community-based investigation. Extensive guidance for IPC in health care facilities is available [38]. (See "Tuberculosis transmission and control in health care settings".)
Studies published in the 1980s suggested a high rate of TB transmission, new infection, and TB disease among older adults in nursing homes. In one study, disease was observed among 5.9 percent of individuals with skin test conversion in the absence of isoniazid therapy [39]. In addition, cohort studies noted lower rates of disease among those who received isoniazid for treatment of LTBI [40,41]. Subsequent studies have not shown comparable rates of infection or disease among LTCF residents, and the benefits of isoniazid appear more modest (with perhaps greater harm) than initially suggested [42-49].
Pathogens spread by contact — Pathogens spread by contact cause outbreaks in LTCFs, either via direct physical contact between individuals or indirect contact; indirect contact occurs when an uninfected individual touches a surface or fomite that has been contaminated by an infected individual.
Key interventions to control an outbreak due to a pathogen transmitted by contact include the following:
●Isolation of infected residents – Contact precautions involve wearing a gown and gloves when entering an infected resident's room and having the resident wear isolation garb if they must leave their room. For patients on contact isolation, disposable or dedicated care equipment (eg, stethoscopes, walkers) can further help to prevent spread.
●Ensuring proper hand hygiene – Hand hygiene is among the most important interventions for stopping spread. For some pathogens (eg, Clostridioides difficile, norovirus), alcohol-based hand gels are ineffective, and switching to soap and water is necessary.
●Enhanced environmental cleaning and disinfection – Because many of these pathogens persist for prolonged periods on surfaces, special attention must be given to cleaning the environment. In some cases, the disinfectant agent used from cleaning must be changed due to resistance of certain pathogens to standard agents.
●Cohorting – In the setting of large outbreaks or outbreaks due to certain highly infectious pathogens, cohorting may be necessary, along with using dedicated trained staff to care for residents in the isolation cohort.
●Treating infected residents and staff – If available, treating infected individuals can help curb the outbreak.
Diarrheal infection — Diarrheal illness may spread rapidly in LTCFs and requires a vigorous IPC response for diagnosis and prevention. The most common source of diarrheal outbreaks is an infected individual, although contaminated food can also cause outbreaks.
Residents of LTCFs are estimated to have the highest incidence of diarrhea in resource-abundant countries [50]. In the United States, approximately 0.05 to 2.0 episodes of gastroenteritis per 1000 patient-days occur among LTCF residents [51]. In Australia between 2002 and 2008, 52 percent of gastroenteritis outbreaks occurred in the nursing home settings; 6.4 percent of patients were hospitalized and 2.7 percent died [52]. Older adults are at increased risk of infection in the setting of decreased gastric acid production, and morbidity and mortality are associated with dehydration [53].
Viral gastroenteritis — Norovirus is the most common cause of diarrheal outbreaks in LTCFs. The virus spreads efficiently from person to person, and food contaminated by a food service provider can cause large outbreaks.
LTCFs are the most common setting for norovirus outbreaks in the United States, and the outbreaks are associated with increased mortality [54].
Because the virus is not killed by alcohol-based hand sanitizer, use of soap and water for hand hygiene is necessary; the virus is also resistant to standard cleaning agents, so bleach solutions are commonly used for environmental cleaning. Nearly half of symptomatic patients shed virus for at least 21 days.
Norovirus is discussed in detail separately, and CDC guidance for managing norovirus outbreaks is available [55]. (See "Norovirus".)
Other viral causes of diarrheal outbreaks include rotavirus, adenovirus, and astrovirus. (See "Acute viral gastroenteritis in adults".)
Clostridioides difficile — C. difficile is the most common cause of health care-associated diarrhea in resource-abundant countries; older adults are disproportionately affected [56]. Among nursing home residents treated with antibiotics in the United States, 8 to 33 percent acquire C. difficile infection, and 10 to 30 percent of LTCF residents are colonized [57]. The incidence has more than doubled in recent decades [58,59]. Disease severity has also increased, especially in those over 60 years of age. Nearly one-half of health care-associated C. difficile infection now occurs in LTCFs [59].
Adequate cleaning of LTCF environments, including removal of spores, is particularly difficult. Soap and water are necessary for hand hygiene (instead of alcohol-based hand gels), and bleach solutions are often necessary for environmental cleaning due to resistance to standard disinfectants.
Antibiotic stewardship within LTCFs is important for prevention of C. difficile infections and outbreaks. Patients with active diarrheal infection should be treated, but there is no role for treatment of C. difficile infection in the setting of asymptomatic carriage.
Issues related to prevention of C. difficile infection, including environmental cleaning and hand hygiene, are discussed further separately. (See "Clostridioides difficile infection: Prevention and control".)
Other pathogens — Other causes of foodborne outbreaks include Salmonella, Staphylococcus, and Escherichia coli O157:H7. In an Australian study of older adult residents of LTCFs between 2005 and 2009, the rates of Salmonella infection were higher and the rates of toxigenic E. coli, Campylobacter, and Shigella lower compared with community residents [60].
Additional causes of diarrheal outbreaks in LTCFs include Shigella, Yersinia, Giardia, and Cryptosporidium. (See "Causes of acute infectious diarrhea and other foodborne illnesses in resource-abundant settings".)
Skin and soft tissue infection — Important skin and soft tissue infections that cause outbreaks in LTCFs include infestations (eg, scabies), viral infections (eg, shingles), and fungal infections (eg, tinea) [61,62].
Scabies — Scabies outbreaks can occur in LTCFs [63,64]. Scabies infection is associated with itch and rash (picture 1 and figure 1). Crusted scabies is a severe form of scabies characterized by scaly lesions with an enormous mite load; pruritus is not always present in crusted scabies (picture 2 and picture 3). Due to the enormous mite load, patients with crusted scabies may be the index case in LTCF outbreaks. (See "Scabies: Epidemiology, clinical features, and diagnosis", section on 'Crusted scabies'.)
The diagnosis of scabies should be confirmed by skin scrapings. Delayed diagnosis may occur in more than 10 percent of patients and is associated with chronic steroid use, acquired immunodeficiency syndrome (AIDS), and long hospitalization [65]. (See "Scabies: Epidemiology, clinical features, and diagnosis", section on 'Diagnosis'.)
Residents with scabies should be treated and placed in contact precautions (including shoe covers in cases of crusted scabies); close contacts (including roommates, staff, and family members) should also be empirically treated [66]. (See "Scabies: Management", section on 'Contacts and environment'.)
Shingles — Herpes zoster (shingles) is a common skin infection in LTCFs and occurs when the varicella zoster virus (VZV) reactivates in patients who had primary VZV infection (ie, chickenpox) earlier in life.
Patients with shingles rarely instigate outbreaks because shingles is much less contagious than chickenpox, and many older individuals cannot acquire the virus due to past infection. Furthermore, VZV vaccination is available to nonimmune individuals and has become a standard childhood vaccine in many countries, including the United States. A separate shingles vaccine is also available and is effective in older individuals [67,68].
Small outbreaks have been reported and are usually due to a patient with shingles who also has underlying immunocompromise. Patients who acquire infection from patients with shingles develop primary VZV infection (chickenpox) and should be isolated in airborne/contact isolation; primary VZV is a highly transmissible pathogen.
Prevention of VZV infection in health care facilities is discussed in detail separately. (See "Prevention and control of varicella-zoster virus in health care facilities".)
Tinea infection — Outbreaks of tinea infection can occur and may be perpetuated by contamination of washing areas, linens, or grooming equipment (picture 4). Measures to control these infections should include prompt treatment of infected individuals, environmental cleaning, and surveillance. Antifungal resistance is emerging in tinea infections [69]. (See "Dermatophyte (tinea) infections".)
Conjunctivitis — Conjunctivitis may occur sporadically or in outbreaks and may be caused by bacterial (such as Staphylococcus aureus) or viral (such as adenovirus) pathogens. It is spread by direct contact with an infected person's secretions or a contaminated object. The incidence in LTCF was 0.6 to 3.5 per 1000 patient-days in one report [70]. (See "Infectious conjunctivitis".)
Group A Streptococcus — Outbreaks of group A Streptococcus (GAS) infection in LTCFs have been described [71,72]. In one review including 1762 cases of invasive GAS infection, the incidence among LTCF residents compared with community-based older adults was 41 versus 7 cases per 100,000 population [71]. Patients in LTCFs were 1.5 times as likely to die from the infection as community-based patients (33 versus 21 percent). Outbreaks may occur over a long period of time, be challenging to identify, and can originate from an asymptomatic carrier [73].
Transmission is predominantly person to person, particularly via direct contact between residents. If a single case of invasive GAS occurs in an LTCF resident, an investigation is typically performed. Interventions include contact tracing and potential testing for colonization among certain staff members. Staff who are epidemiologically linked to infected residents may undergo empiric treatment to try to eradicate colonization. The CDC has issued guidance [74], and IPC is discussed in further detail separately. (See "Invasive group A streptococcal infection and toxic shock syndrome: Treatment and prevention", section on 'Prevention'.)
Clinical syndromes due to GAS include cellulitis, toxic shock syndrome, pharyngitis, bronchitis, pneumonia, and bacteremia. These are discussed further separately. (See "Treatment and prevention of streptococcal pharyngitis in adults and children" and "Invasive group A streptococcal infection and toxic shock syndrome: Epidemiology, clinical manifestations, and diagnosis".)
Antimicrobial-resistant organisms — Multidrug-resistant organisms (MDROs) are more common in LTCFs than hospitals in the United States [75-78].
MDROs cause numerous infectious syndromes, including urinary tract infection, pneumonia, wound infections, device-related infections, and bacteremia.
Over 35 percent of United States nursing home residents are colonized with MDROs, and colonization is a major risk factor for subsequent development of an active infection [77,79,80]. Many residents have extensive histories of health care exposure and indwelling devices, both of which are risk factors for MDROs.
The LTCF environment poses challenges to MDRO prevention [78,81,82]. Organisms may be transferred between acute care facilities and LTCFs via LTCF residents, and transmission can occur via contact with colonized skin, fecal-oral transmission, or contaminated surfaces. In addition, there is often considerable antibiotic overuse.
Basic IPC interventions play an integral role to preventing spread of MDROs, especially hand hygiene, patient bathing/cleansing, proper wound and device care, and environmental cleaning and disinfection. A randomized trial has found that universal decolonization of all residents may prevent spread of MDROs [83].
Routine isolation of colonized residents is advocated by some but is often difficult due to the large number of colonized residents in some LTCFs and the prolonged duration of colonization in many patients; prolonged isolation in LTCFs markedly alters the quality of life of affected residents [84].
In the setting of an outbreak, additional interventions may include screening for colonization along with isolation and treatment of colonized residents [84].
Numerous MDROs can spread within LTCFs [80,85-90]; several are detailed below.
Methicillin-resistant Staphylococcus aureus — Approximately 10 to 50 percent of LTCF residents in United States are colonized with methicillin-resistant S. aureus (MRSA); one study including 412 residents reported a MRSA prevalence rate of 58 percent [91]. Risk factors for MRSA colonization in LTCFs include antimicrobial use, dependence on health care personnel for assistance with activities of daily living, presence of decubitus ulcers, and kidney dysfunction [92,93].
Issues related to prevention and control of MRSA are discussed further separately, and guidelines have been published for acute care hospitals [94]. (See "Methicillin-resistant Staphylococcus aureus (MRSA) in adults: Prevention and control".)
Multidrug-resistant gram-negative bacilli — Prevalence of multidrug-resistant gram-negative bacilli is increasing, and LTCFs are a major source of spread [95]. These pathogens are becoming increasingly difficult to treat due to the level of resistance.
Such pathogens include extended-spectrum beta-lactamase-producing bacteria, multidrug-resistant Pseudomonas spp, carbapenem-resistant Enterobacterales, and Acinetobacter baumannii. These organisms are discussed in-depth in dedicated UpToDate topics. (See "Extended-spectrum beta-lactamases" and "Epidemiology, microbiology, and pathogenesis of Pseudomonas aeruginosa infection" and "Carbapenem-resistant E. coli, K. pneumoniae, and other Enterobacterales (CRE)" and "Acinetobacter infection: Epidemiology, microbiology, pathogenesis, clinical features, and diagnosis".)
Residents of LTCFs are at increased risk for acquisition of multidrug-resistant gram-negative bacteria. Risk factors include prior antibiotic use, mechanical ventilation, fecal incontinence, urinary catheterization, older age, cognitive deterioration, and malnutrition [6,85-89,96-100].
In some facilities, colonization rates with these strains are comparable with or higher than colonization rates in acute care hospitals [98,99,101-105]. The use of bundled interventions for prevention of infection due to drug-resistant gram-negative organisms is discussed separately. (See "Principles of infection prevention and control in long-term care facilities", section on 'Bundled interventions'.)
Vancomycin-resistant Enterococcus — The colonization rate of vancomycin-resistant Enterococcus (VRE) in LTCFs is variable. One study including 100 residents of 20 different LTCFs admitted to an acute care hospital noted 45 percent of patients were colonized with VRE on admission [106]. Another study including 1215 LTCF residents noted a VRE carriage rate of 9.6 percent [107].
A meta-analysis of VRE infections in LTCFs found a higher mortality with VRE bloodstream infections compared with those caused by vancomycin-susceptible isolates [90].
Issues related to prevention of VRE infection are discussed further separately. (See "Vancomycin-resistant enterococci: Epidemiology, prevention, and control".)
Candida auris — C. auris is an emerging pathogen of concern. Unlike other Candida spp, C. auris is intrinsically resistant to multiple classes of antifungal agents, spreads efficiently in health care facilities, persists for prolonged periods on surfaces, and is resistant to many standard disinfectants used for environmental cleaning [95,108].
Outbreaks within LTCFs have been reported [109-112]. Major risk factors include mechanical ventilation, tracheostomies, serious underlying medical comorbidities, frequent health care exposure, exposure to broad-spectrum antibiotics or antifungals, and health care devices (eg, feeding tubes, central venous catheters, urinary catheters) [108].
Cases of C. auris are required in some locales to be reported to public health authorities. Guidance for management of outbreaks in health care facilities is available from the CDC [113].
Drug-resistant pneumococcus — Pneumococcal vaccination has led to an overall reduction in the prevalence of invasive pneumococcal infections [114]. However, penicillin-resistant strains persist, and outbreaks within LTCFs have been reported [115]. LTCFs have also been associated with outbreaks of multidrug-resistant pneumococcus, including isolates resistant to ceftriaxone [116,117].
Bloodborne and sexually transmitted pathogens — Transmission of HIV, hepatitis B, and hepatitis C in LTCFs can occur; both bloodborne and sexual transmission have been described.
Outbreaks have been reported in LTCFs as well. In a review of all hepatitis B and C outbreaks reported to the CDC from 2009 to 2019, 19 hepatitis B outbreaks were identified, and 15 (79 percent) were due to improper use of blood glucose monitors [118]. One outbreak of hepatitis C in an LTCF was identified and was associated with podiatry care, phlebotomy, and nail care performed at the facility.
Outbreaks of HIV within nursing homes are extremely rare [119]. Sexual transmission has been documented within LTCFs caring for the severely mentally ill [120].
Prevention of the spread of bloodborne pathogens within facilities is primarily based on proper use of standard precautions with all patients and safe and proper performance of procedures (eg, phlebotomy, injections) and use of medical equipment (eg, glucose monitors). (See "Infection prevention: Precautions for preventing transmission of infection", section on 'Standard precautions' and "Infection control in the outpatient setting", section on 'Safe injection practices'.)
Every facility should have a protocol and staff training for management of health care workers and residents who have a potential bloodborne pathogen exposure, including prompt access to post-exposure prophylactic medication if indicated. (See "Management of health care personnel exposed to HIV" and "Prevention of hepatitis B virus and hepatitis C virus infection among health care providers".)
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" and "Society guideline links: COVID-19 – Long-term care facilities".)
SUMMARY AND RECOMMENDATIONS
●Spread of infection – In long-term care facilities (LTCFs), the patient population is at especially high risk for developing infection, and the environment provides ample opportunity for spread. (See 'Spread of infection' above.)
●Detection of outbreaks – An outbreak is defined as an unusual increase in illness above the facility's baseline levels. In many cases, an outbreak is detected by care providers within the facility who notice a cluster of similar illnesses over a short period of time.
If an outbreak is suspected, testing of affected residents should be performed to determine the underlying pathogen. (See 'Detection of outbreaks' above.)
●General approach – Overarching interventions for outbreak management include the following (see 'General approach' above):
•Notification of local public health department.
•Development of a case definition and identifying affected individuals.
•Determination of containment measures – Potential containment measures include isolation of infected residents, cohorting of infected residents, quarantining exposed residents, and furloughing exposed staff.
•Prevention of further spread – Methods to prevent spread include addressing environmental routes of transmission (eg, air ventilation, environmental cleaning), treating infected residents and staff, providing prophylaxis and/or vaccination, restricting visitors, and notifying transferring facilities.
●Outbreaks due to specific pathogens
•Respiratory pathogens – Numerous pathogens, especially respiratory viruses, can cause outbreaks characterized by rapid spread, large numbers of infected residents and staff, and severe illness. Respiratory pathogens include SARS-CoV-2, influenza virus, respiratory syncytial virus (RSV), Legionella spp, and Mycobacterium tuberculosis. (See 'Respiratory pathogens' above.)
•Pathogens spread by contact – Pathogens spread by contact cause outbreaks via either direct physical contact between individuals or indirect contact; indirect contact occurs when an uninfected individual touches a surface or fomite that has been contaminated by an infected individual. (See 'Pathogens spread by contact' above.)
-Diarrheal infection (eg, viral gastroenteritis, Clostridioides difficile, foodborne bacteria). (See 'Diarrheal infection' above.)
-Skin and soft tissue infection (eg, scabies, shingles, tinea infection, group A Streptococcus [GAS]). (See 'Skin and soft tissue infection' above.)
-Viral conjunctivitis. (See 'Conjunctivitis' above.)
-Antimicrobial-resistant organisms (eg, methicillin-resistant Staphylococcus aureus [MRSA], multidrug-resistant gram-negative bacilli, vancomycin-resistant Enterococcus [VRE], Candida auris). (See 'Antimicrobial-resistant organisms' above.)
•Bloodborne pathogens and sexually transmitted diseases (eg, HIV, hepatitis B, hepatitis C) – (See 'Bloodborne and sexually transmitted pathogens' above.)
ACKNOWLEDGMENT —
The UpToDate editorial staff acknowledges Rhonda Stuart, MD, who contributed to an earlier version of this topic review.
