INTRODUCTION
Korea became an aging society in 2000, with an older adult population exceeding 7% and has since exceeded 14% in just 17 years. Since the mid-2000s, the number of long-term care hospitals (LTCHs) caring for older adults began to surge, reaching 800 in 2010, exceeding 1,400 in 2016, and reaching 1,470 by July 2019.
1) Some of the most common illnesses presented by patients admitted to LTCHs in Korea include dementia, cerebrovascular disease, Parkinson disease, hypertension, and diabetes mellitus. Most of these patients are older adults and thus have reduced immunity.
1,2) In LTCHs, an individual care provider tends to cater to multiple patients, which increases the facility’s risk for the development and transmission of infectious diseases. Thus, active infection surveillance and preventive activities are required.
One previous study revealed that 53.7% had indwelling urinary catheters inserted, and 38.7% had infectious diseases such as pneumonia, urinary tract infection, and bloodstream infection among Korean LTCH inpatients.
3) The agents of bloodstream infection were gram-positive bacteria (34.8%), gram-negative bacteria (31.3%), multidrug-resistant bacteria (13.0%), and methicillin-resistant
Staphylococcus aureus (MRSA) (8.7%).
4)
Investigation of the current status of healthcare-associated infections (HAIs) is essential for systematic and efficient infection control in LTCHs.
4,5) In contrast to acute care facilities, LTCHs mostly treat patients undergoing rehabilitation and older patients requiring long-term care; both are populations with complex and diverse comorbidities. Furthermore, even with serious infections, more than half of these patients do not present with fever,
6) and HAIs manifest differently from those observed in acute care facilities. Therefore, the diagnostic criteria for HAIs in LTCHs differ from those used in acute care facilities.
6,7)
The US Centers for Disease Control and Prevention (CDC) developed a national standard for infection surveillance in long-term care (LTC) facilities
8) using the HAI-related surveillance criteria for LTC facilities developed by McGeer via a Delphi technique using a panel comprising infection specialists, gerontologists, and infection control personnel.
7,9) LTC facilities in the United States are defined as those that provide medical and non-medical support and care to older adults and vulnerable individuals who cannot live independently in the community. These facilities include nursing homes, skilled nursing facilities, LTCHs, intermediate/chronic care facilities for the developmentally disabled, assisted-living facilities, and residential care facilities.
10) Particularly, LTCHs provide medical treatment and rehabilitation treatment to individuals with chronic and complex problems requiring long-term hospital-level care.
10) LTCHs in Korea have mixed functions that are equivalent to LTCHs in the United States, which provide long-term treatment, and to LTC facilities, which focus on providing medical and non-medical support and care.
11)
The McGeer HAI diagnostic criteria were developed for patients in LTC facilities who have difficulty undergoing blood and imaging tests. In 2012, the surveillance criteria for urinary tract infections (UTIs) and respiratory tract infections (RTIs) were revised to increase the specificity for these infections, and the definitions for norovirus gastroenteritis and
Clostridium difficile infection were newly added to minimize the gap between the diagnostic criteria used by acute care and LTC facilities.
9,12)
In Korea, the Korean Society for Healthcare-associated Infection Control and Prevention (KOSHIC) and the Korea CDC implemented an HAI surveillance method in 2006 primarily for intensive care unit and surgical site infections surveillance.
13) However, LTCHs have lower percentages of severely ill and surgical patients but a higher percentage of older long-term inpatients compared to acute care facilities. Thus, it is inappropriate to conduct HAI surveillance based on the nationwide HAI criteria focused on acute care facilities. Furthermore, surveillance data should be obtained using valid and reliable surveillance criteria so that the data can be compared to those of other healthcare facilities in Korea and HAI surveillance results from other countries. Thus, it is necessary to develop and assess the surveillance criteria for HAIs in LTCHs in Korea.
This study aimed to develop an HAI surveillance method appropriate for LTCHs that primarily admit older patients requiring LTC and to investigate the current status of HAIs in LTCHs in Korea to systematize and standardize HAI surveillance and contribute to prevention of HAI in such facilities.
DISCUSSION
This is the first study to adapt and apply the McGeer infection surveillance definition, which was developed for LTC facilities lacking adequate manpower and resources for infection surveillance,
8,9) for use in Korea. The modified version differed from the CDC’s HAI surveillance method standard for LTC facilities in that the diagnostic criteria included systemic infections due to inadequate HAI surveillance experience and data in LTCHs, axillary temperature criterion for fever because of its common use in LTCHs in Korea, and 10 items rated on a 5-point scale based on the ADL scoring system reported to the HIRA by LTCHs in Korea.
1)
In addition, considering the reality in LTCHs in which infection control personnel cannot spare adequate time for infection surveillance, we performed passive surveillance, in which nurses providing direct care to patients checked for symptoms included in the HAI surveillance diagnostic criteria, such as fever, increased leukocyte count, altered consciousness, reduced functioning, urinary and bowel dysfunctions, skin and mucosal lesions, and digestive symptoms, and periodically reported to the infection control personnel. While active infection surveillance is the most effective method to investigate HAIs, combining passive infection surveillance amid the inadequate infection surveillance infrastructure in LTCHs in Korea was one difference from the nationwide infection surveillance method focusing on acute care facilities.
13)
During the recent coronavirus disease 2019 (COVID-19) pandemic, infection control has become critical in LTCHs that generally provide care to older patients. The COVID-19 guidelines for LTCHs developed by the Korean Geriatrics Society are a good example of infection control.
14) In addition, as caregiving staff, including nurses, actively monitor suspected COVID-19 symptoms, such as respiratory symptoms, fever, and digestive symptoms, we recommend a systematic combination of passive infection surveillance, in which the infection surveillance personnel are given a report, and active infection surveillance, which involves a direct investigation by the infection surveillance personnel.
A total of 192 cases of HAIs were reported by six LTCHs, corresponding to an incidence rate of 30.38%. This rate differed from that previously reported in LTC facilities (3.4% and 4.1%)
15,16) using the 2012 updated version of the McGeer criteria.
9,12) This difference could be attributed to the addition of unexplained febrile illness in our study. Another explanation may be the high prevalence of frailty among LTCH patients who are more physically vulnerable compared to those in other nursing homes.
17)
Rothan-Tondeur et al.
16) reported bronchitis (35.5%) to be the most common type of HAI, followed by gastroenteritis (23.8%), UTI (16.7%), otorhinolaryngological infection (8.7%), and pneumonia (7.0%). In our study, the most common type of HAI was unexplained febrile infection (40.6%), followed by pneumonia (20.8%), lower RTI (14.1%), and gastroenteritis (10.9%). The high rate of unexplained febrile illness could explain the higher infection rate compared to that reported previously. In the future, the rate of unexplained febrile illness may be lowered by identifying the cause of fever.
In our study, the incidence of HAI per 1,000 days of hospital stay was 1.57. The National Healthcare Safety Network (NHSN), an infection surveillance module for LTC facilities in the United States, includes UTI,
C. difficile and multi-resistant bacteria infection, and hand hygiene and protective device compliance surveillance.
18) Notably, it was difficult to directly compare the results obtained from the surveillance method used in our study to that used for US infection surveillance due to the differences in these methods. Yet, the NHSN reported an incidence of 0.59 per 1,000 days of hospital stays for UTI and 0.98 per 1,000 days of hospital stays for
C. difficile infection between 2013 and 2015
19) while we observed no cases of UTI and three cases of
C. difficile infection (0.0024 per 1,000 days of hospital stay). These two types of infections may be difficult to diagnose, as microbial testing is needed for diagnosing them; however, LTCHs are not equipped with the resources for their own microbial testing, and the process of requesting it at an external laboratory is time- and labor-intensive. The McGeer criteria for UTI did not require microbial testing at the time of development in 1991; however, microbial testing was added in the 2012 update to increase the specificity to decrease unnecessary use of resources.
12) As the resource utilization group system was used as the payment model in LTCHs in Korea,
2) it was practically difficult to prescribe microbial testing. Thus, it was difficult to apply the McGeer criteria for UTI based on microbial testing.
In our study, RTI was the second-most common type of HAI after unexplained febrile illness. According to the European data applying the same McGeer criteria,
20) UTI was the most common infection in LTC facilities, followed by RTI and skin infection. In Korea, the diagnosis of UTI is limited by the difficulty in obtaining prescriptions for microbial tests; thus, in our study, RTI was a more frequently diagnosed HAI among patients under long-term care in LTCHs because the diagnosis does not require microbial tests. Furthermore, respiratory symptoms are the main symptoms of the current COVID-19 pandemic,
21) highlighting the importance of RTI prevention in LTCHs. Furthermore, Quach et al.
22) reported that patients aged 65 years or older who visited the emergency department of an acute care facility had risks of developing RTIs and digestive tract infections. Since patients are frequently transferred between LTCHs and acute care facilities, collective efforts are needed to prevent HAIs.
This study has some limitations. First, the findings are not generalizable because only six LTCHs that chose to participate were monitored for a relatively short period of 2–3 months. Second, there is a potential bias as some HAIs are underdiagnosed because of the difficulty in obtaining prescriptions for microbial tests for diagnoses. However, all cases were reviewed twice and the authors and the infection surveillance personnel in each LTCH tried to improve the accuracy and sensitivity of cases with periodic online Q&A discussions and sharing of ambiguous cases. Third, LTCH-specific medical fee regulation of the resource utilization group payment system could have constricted microbiological laboratory studies such as urine or blood culture. In the future, improvements in manpower, health insurance systems, and surveillance systems are needed for more LTCHs to continuously participate in HAI surveillance.
In conclusion, the surveillance method applied in our study can be used to assess the infection control methods and level of infection control activities in LTCHs. Particularly, the HAI diagnostic criteria, surveillance form, and checklist that were developed based on the characteristics of inpatients under LTC could contribute substantially to the systematization and standardization of HAI surveillance in LTCHs. Standardizing the surveillance method and investigating the infection rates and infection risk factors will help to prevent HAIs in LTCHs.