On September 6, 2018, the Washoe County Health District in Reno, Nevada, was notified of a Klebsiella pneumoniae carbapenemase (KPC)–producing Escherichia coli recovered from the blood of a patient who presented to a hospital with a urinary tract infection and bacteremia. The patient was a resident of a group home for adults with chronic medical conditions. We describe the public health investigation to assess for potential transmission of KPC-producing organisms in a group home for adults and to prevent further spread.
Methods
Setting
Group homes are residential care facilities that provide housing, meals, and care to persons who are unable to live independently. Reference Kossover, Chi, Wise, Tran, Chande and Perz1
The group home in this study is a single-family home for adults in a residential neighborhood with 4 bedrooms, 3 bathrooms, a kitchen, dining room, and living room. The group home staff include caregivers and visiting healthcare personnel (VHCP). Caregivers provide 24-hour assistance to the residents. VHCP provide specialized medical services for limited periods (eg, physical therapy).
Case finding, epidemiologic investigation, and infection prevention and control (IPC) assessment
The Nevada Division of Public and Behavioral Health, the Washoe County Health District, and the Centers for Disease Control and Prevention began a public health investigation following the identification of the index case. Group home residents were then screened for colonization with KPC-producing organisms. Due to the close contact among staff and group home residents, staff were also offered screening.
A case was defined as detection of bla KPC from a screening swab or clinical isolate from any resident or staff residing or working in the group home from June 1 through October 26, 2018. For this study, 2 physicians and 1 public health epidemiologist reviewed group home records of all residents to collect information regarding comorbidities, medications, and hospitalizations. We reviewed residents’ roommate history, caregivers, bedroom location(s), and assigned bathroom(s). We used semistructured interviews to understand staff responsibilities. We collected information regarding each resident’s ability to perform activities of daily living (ADLs) defined as bathing, toileting, dressing, eating, mobility, and transferring in and/or out of a bed or chair. We conducted IPC observations over a 5-day period, focusing on caregiver practices.
We assessed IPC knowledge, practices, and training among staff and residents. We observed hand hygiene, use of personal protective equipment (PPE), environmental cleaning and disinfection, food preparation, and laundry activities. Activities defined as high risk for transmission of pathogens included cleaning toilets and showers, handling soiled linens, and assisting residents with bathing and toileting. Reference Blanco, Johnson and Sorkin2
Laboratory investigation
Rectal swabs and isolates were screened using the GeneXpert Carba-R assay. Swabs with bla KPC detected were plated on MacConkey agar, and isolates with bla KPC detected underwent species identification using a Phoenix100 automated microbiology system (Becton Dickinson, Franklin Lakes, NJ). Genomic libraries were prepared using Nextera DNA Flex Library Prep Kit (Illumina, San Diego, CA) and sequencing was performed using an Illumina MiSeq platform. Bioinformatic analyses were completed using the QuAISAR-H pipeline (https://github.com/nvlachos/QuAISAR-H). SNVPhyl was used to assess genetic relatedness of sequenced isolates. Reference Petkau, Mabon and Sieffert3
Results
Case finding
We identified 19 individuals for colonization screening and interviews: 7 residents, 3 caregivers, 9 VHCP. In total, 13 individuals agreed to screening; 5 (39%) were colonized with KPC-producing organisms (Fig. 1). Also, 5 VHCP declined screening and 1 resident died prior to being screened.
Fig. 1. Screening assessments and blaKPC case finding.
Resident epidemiologic investigation
The median age of the group home residents was 79 years (range, 72–92 years). Seven residents (88%) required moderate to total assistance with bathing and 6 (75%) with ambulation. All residents with KPC had shared the same bathroom prior to being screened and had been hospitalized within the previous 4 months. The index case died within 30 days of bla KPC detection. None of the residents who screened positive for KPC colonization progressed to clinical infection.
Caregivers and VHCP epidemiologic investigation
The 3 caregivers included 2 paid employees who typically spent multiple consecutive days and nights in the group home and 1 volunteer who worked during the day only. Furthermore, 1 bedroom and 1 bathroom were dedicated for caregiver use. All caregivers prepared meals and assisted residents with high-risk activities, cleaned and disinfected surfaces throughout the group home, and laundered residents’ clothing and linens.
We interviewed 7 VHCP; most VHCP worked with a single resident 1–3 times per week for 30–60-minute intervals in common areas. Most VHCP had received formal IPC training. Only 1 VHCP interviewed reported performing high-risk activities.
Observations of IPC practices
None of the caregivers had formal IPC training. Availability of alcohol-based hand rub was limited, and caregivers lacked awareness regarding recommended hand-washing moments. Caregivers exhibited poor adherence to hand hygiene during resident care activities. Resident hand hygiene was not routinely performed prior to meals. Caregivers lacked knowledge regarding appropriate indications for PPE. Despite being responsible for all environmental cleaning and disinfection, caregivers did not know appropriate contact times for cleaning products nor the importance of applying friction when cleaning surfaces. Caregivers simultaneously performed environmental cleaning and disinfection, handled soiled clothing and linens, toileted residents, and prepared food without performing hand hygiene between these activities.
IPC interventions
We adapted existing IPC guidance for nursing homes 4 that applied to specific practices performed in the group home (Supplemental Appendix A online), and we trained caregivers regarding these practices. We helped caregivers develop a standard workflow for daily activities with separation of environmental cleaning and disinfection, resident care, and food preparation.
A point prevalence survey including all 6 GH A residents and 3 caregivers was conducted 1 month following the implementation of IPC practices, and no additional cases were identified.
Isolate characterization
Among 5 rectal swabs with bla KPC detected, KPC-producing E. coli was identified from 4 (no organism was recovered from the fifth). Whole-genome sequencing was performed on 5 KPC-producing E. coli isolates (including the index case); all were sequence type (ST) 1193, all carried bla KPC-3, and all varied by 1–29 high-quality, single-nucleotide variants across a 96.7% conserved core genome. The raw data are available on CDC HAI-Seq PRJNA288601 (https://www.ncbi.nlm.nih.gov/bioproject/288601).
Discussion
In this report, we describe transmission of an emerging pathogen, KPC-producing E. coli ST1193, in a group home, likely facilitated by limited IPC knowledge among caregivers. This investigation highlights the potential for fit E. coli strains to acquire carbapenemases and to spread among individuals outside of a traditional healthcare setting. E. coli ST1193 has exhibited marked clonal expansion in the United States during the last decade. Reference Tchesnokova, Rechkina and Larson5 Although all E. coli ST1193 isolates are fluoroquinolone resistant, no reports of KPC production have been published previously.
Across the United States, there are nearly 30,000 residential care communities with ~800,000 residents. 6 Residential care communities are licensed independently by each state and have variable regulations regarding IPC standards. Among residents living in this setting, 40% have chronic conditions and often require caregiver assistance with medical management and ADLs. 6 In our investigation, streamlining daily activities, standardizing workflow processes, and teaching basic IPC practices to caregivers contributed to stopping the outbreak.
This study has several limitations. We were unable to determine whether the index case was the initial case in this group home. Additionally, we did not screen 5 VHCP and 1 resident; thus, we may have missed additional cases.
Identification of emerging antibiotic-resistant organisms should prompt a public health investigation to evaluate transmission in non-healthcare settings where resident risk factors and care practices increase the likelihood of spread. 7 Caregivers in group homes are an important audience for targeted IPC training to limit the spread of resistant organisms and might benefit from IPC recommendations developed for this group home.
Supplementary material
To view supplementary material for this article, please visit https://doi.org/10.1017/ice.2020.279
Acknowledgments
This work was supported by Joel Sevinsky from the Colorado Department of Public Health and Environment and Logan Fink from the Colorado State Public Health Lab. The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention. The use of trade names is for identification only and does not imply endorsement by the Centers for Disease Control and Prevention.
Financial support
No financial support was provided relevant to this article.
Conflicts of interest
All authors report no conflicts of interest relevant to this article.
