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For primary care clinics at a Veterans’ Affairs (VA) medical center, the shift from in-person to telehealth visits during the coronavirus disease 2019 (COVID-19) pandemic was associated with low rates of antibiotic prescription. Understanding contextual factors associated with antibiotic prescription practices during telehealth visits may help promote antibiotic stewardship in primary care settings.
Contaminated shoes are a potential vector for dissemination of healthcare-associated pathogens. We demonstrated that healthcare personnel walking into patient rooms frequently transferred pathogens from their shoes to the floor. An 8-second treatment of shoes with a UV-C decontamination device significantly reduced the frequency of transfer of vegetative bacterial pathogens.
In a randomized trial, patients wearing slippers whenever out of bed transferred bacteriophage MS2 from hospital room floors to patients and surfaces significantly less often than controls not provided with slippers. Wearing slippers could provide a simple means to reduce the risk for acquisition of healthcare-associated pathogens from contaminated floors.
In this large, retrospective cohort study, we used administrative data to evaluate nonpregnant adults with group B Streptococcus (GBS) bacteriuria. We found greater all-cause mortality in those with urinary tract infections compared to asymptomatic bacteriuria. Differences in patients’ baseline characteristics and the 1-year mortality rate raise the possibility that provider practices contribute to differences observed.
In a randomized trial, adjunctive ultraviolet-C light treatment with a room decontamination device and sodium hypochlorite delivered via an electrostatic sprayer were similarly effective in significantly reducing residual healthcare-associated pathogen contamination on floors and high-touch surfaces after manual cleaning and disinfection. Less time until the room was ready to be occupied by another patient was required for electrostatic spraying.
In an unventilated room, 2 commercial portable air cleaners with high efficiency particulate air (HEPA) filters and a do-it-yourself box fan air cleaner with minimum efficiency reporting value (MERV)-13 filters significantly reduced aerosolized bacteriophage MS2. Increasing airflow and addition of ultraviolet-C light plus titanium dioxide–generated photocatalytic oxidation enhanced viral clearance.
To assess the prevalence of antibiotic-resistant gram-negative bacteria (R-GNB) among patients without recent hospitalization and to examine the influence of outpatient antibiotic exposure on the risk of acquiring R-GNB in this population.
2-year retrospective cohort study.
Regional Veterans Affairs healthcare system.
Outpatients at 13 community-based clinics.
We examined the rate of acquisition of R-GNB within 90 days following an outpatient visit from 2018 to 2019. We used clinical and administrative databases to determine and summarize prescriptions for systemic antibiotics, associated infectious diagnoses, and subsequent R-GNB acquisition among patients without recent hospitalizations. We also calculated the odds ratio of R-GNB acquisition following antibiotic exposure.
During the 2-year study period, 7,215 patients had outpatient visits with microbiological cultures obtained within 90 days. Of these patients, 206 (2.9%) acquired an R-GNB. Among patients receiving antibiotics at the visit, 4.6% acquired a R-GNB compared to 2.7% among patients who did not receive antibiotics, yielding an unadjusted odds ratio of 1.75 (95% confidence interval, 1.18–2.52) for a R-GNB following an outpatient visit with versus without an antibiotic exposure. Regardless of R-GNB occurrence, >50% of antibiotic prescriptions were issued at visits without an infectious disease diagnosis or issued without documentation of an in-person or telehealth clinical encounter.
Although the rate of R-GNBs was low (2.9%), the 1.75-fold increased odds of acquiring a R-GNB following an outpatient antibiotic highlights the importance of antimicrobial stewardship efforts in outpatient settings. Specific opportunities include reducing antibiotics prescribed without an infectious diagnosis or a clinical visit.
For 40 patients with methicillin-resistant Staphylococcus aureus (MRSA) colonization, fist bump and elbow bump greetings resulted in frequent transfer of MRSA (25% vs 15%, respectively), but significantly fewer colonies were transferred via the elbow bump. Noncontact greetings should be encouraged to reduce the risk of transfer of healthcare-associated pathogens.
Background: Group B Streptococcus (GBS) can cause life-threating invasive infections, yet GBS is also a normal component of the intestinal and genitourinary tract. Although it is regarded as a potential urinary pathogen, the morbidity and mortality associated with recovery of GBS from urine cultures of nonpregnant adults is not well understood. We evaluated characteristics and mortality among nonpregnant adults with urine cultures that grew GBS. Methods: Using administrative data from the Veterans’ Healthcare Administration (VHA), we conducted a retrospective cohort study of VA healthcare system users from January 1, 2008, through December 31, 2017, with monomicrobial urine cultures growing ≥100,000 colony-forming units of GBS. Urinary tract infection (UTI) cases were defined as urinalysis positive for leukocyte esterase and pyuria (≥10 white blood cells), an International Classification of Diseases (ICD) code for UTI, and an antibiotic prescription. Cases with colonization were defined as negative for leukocyte esterase and pyuria, no ICD code for UTI, and no antibiotic prescription. Cases not meeting either definition were deemed unclassifiable. We compared demographics, comorbidities, and all-cause mortality among these 3 groups. Results: Over the 10-year study period, 26,848 veterans had 30,740 urine cultures positive for GBS. Applying the definitions above, there were 2,807 cases of infection, 8,789 cases of colonization, and 15,252 cases that were unclassifiable. Patients with a GBS UTI were slightly older compared to those who were colonized, with a higher Charlson comorbidity index and greater burden of chronic renal disease (Table 1). Individuals with infection versus colonization had 30-day mortality rates of 1% and 0%, respectively, and 1-year mortality rates of 9% and 4%, respectively (Figure 1). Conclusions: The association of a greater burden of illness among veterans who met our definition of UTI compared to colonization might be more reflective of providers’ responses to patients with chronic medical conditions rather than a difference in GBS as a cause of UTI. Overall, the prospect of a urine culture that grows GBS does not appear to be associated with adverse long-term outcomes.
Background: The influence of increased use of telehealth during the emergence of COVID-19 on antibiotic prescriptions in outpatient settings is unknown. The VA Northeast Ohio Healthcare System has 13 community-based outpatient clinics (CBOCs) that provide primary and preventive care. We assessed changes in antibiotic prescriptions that occurred as care shifted from in-person to telehealth visits. Methods: Using VHA administrative databases, we identified all primary care CBOC visits between January 1, 2019, and December 31, 2020, that included a diagnosis for an acute respiratory infection (ARI), a urinary tract infection (UTI), or a skin or soft-tissue infection (SSTI), excluding visits with >1 of these diagnoses or with additional infectious diagnoses (eg, pneumonia, influenza). We summarized the proportion of telehealth visits and the proportion of patients prescribed antibiotics at quarterly intervals. We specifically assessed outpatient visits from April to December 2019 compared to the same months in 2020 to account for seasonality while analyzing diagnosis and antibiotic trends in the emergence of the COVID-19 pandemic. Results: The patients receiving care in April–December 2019 compared to April–December 2020 were similar (Table 1). From April through December 2019, 90% of CBOC primary care visits with a diagnosis for ARI, UTI, or SSTI were in-person, and antibiotics were prescribed at 63%, 46%, and 65% of visits in either modality, respectively (Figure 1). From April through December 2020, only 33% of CBOC primary care visits for ARI, UTI, and SSTI were in person, and antibiotics were prescribed at 46%, 38%, and 47% of visits in either modality, respectively. Comparing April–December in 2019 and 2020, the number of CBOC visits for ARI fell by 76% (2,152 visits to 509 visits), with a more modest decline of 20% and 35% observed for UTI and SSTI visits. In-person visits for ARIs and SSTIs were more likely than telehealth visits to result in an antibiotic prescription (Figure 2). Conclusions: Among the CBOCs at our healthcare system, an increase in the proportion of telehealth visits and a reduction in ARI diagnoses occurred after the emergence of COVID-19. In this setting, we observed a reduction in the proportion of visits for ARIs, UTIs, and SSTIs that included an antibiotic prescription.
Background: Outcomes among nursing home residents with asymptomatic compared to symptomatic COVID-19 are not well characterized. We assessed all-cause mortality among Veterans’ Affairs (VA) community living center (CLC) residents; we compared those residents with a negative SARS-CoV-2 test to residents with symptomatic, presymptomatic, and asymptomatic SARS-CoV-2 infections. Methods: We conducted a national retrospective cohort study of CLC residents tested for COVID-19 between March 1 and July 31, 2020, based on data compiled through the VA COVID-19 shared data resource. Among those with a positive SARS-CoV-2 test, residents were considered symptomatic if they had experienced COVID-19 symptoms in the 30 days prior to the test. Residents were considered presymptomatic if they did not experience symptoms in the 30 days prior to testing and developed a fever (>38°C) or required supplemental oxygen within 14 and 60 days, respectively, following the test. Residents were considered asymptomatic in the absence of these pre- and posttest symptoms. Results: From March 1 to July 31, 2020, of 9,052 CLC residents screened for COVID-19, 8,325 (92%) tested negative (Table 1). Among 727 residents with positive tests, 467 (64%) were symptomatic, 88 (12%) were presymptomatic, and 172 (24%) remained asymptomatic. We observed significant differences in the racial makeup of these disease groups. Among CLC residents who were symptomatic or presymptomatic, 176 (32%) of 555 were black compared to 39 (23%) of 172 who were asymptomatic and 1,810 (22%) of 8,325 who tested negative for SAR-CoV-2. All-cause 30-day mortality rates for symptomatic and presymptomatic residents were 25% and 34%, respectively, which exceeded the all-cause 30-day mortality of asymptomatic residents (12%) and residents with a negative test (6%) (Figure 1). Conclusions: More than one-third of CLC residents with COVID-19 were asymptomatic at the time of testing. This finding highlights the importance of vigilant infection prevention and control measures. Our finding that mortality among presymptomatic residents exceeded that of symptomatic residents raises consideration for enhancing supportive care measures, such as supplemental oxygen and mitigation of inflammatory reactions, as a means to reduce mortality among nursing home residents with presymptomatic SARS-CoV-2 infections.
We examined the impact of microbiological results from respiratory samples on choice of antibiotic therapy in patients treated for hospital-acquired pneumonia (HAP) or ventilator-associated pneumonia (VAP).
Four-year retrospective study.
Veterans’ Health Administration (VHA).
VHA patients hospitalized with HAP or VAP and with respiratory cultures between October 1, 2014, and September 30, 2018.
We compared patients with positive and negative respiratory culture results, assessing changes in antibiotic class and Antibiotic Spectrum Index (ASI) from the day of sample collection (day 0) through day 7.
Between October 1, 2014, and September 30, 2018, we identified 5,086 patients with HAP/VAP: 2,952 with positive culture results and 2,134 with negative culture results. All-cause 30-day mortality was 21% for both groups. The mean time from respiratory sample receipt in the laboratory to final respiratory culture result was longer for those with positive (2.9 ± 1.3 days) compared to negative results (2.5 ± 1.3 days; P < .001). The most common pathogens were Staphylococcus aureus and Pseudomonas aeruginosa. Vancomycin and β-lactam/β-lactamase inhibitors were the most commonly prescribed agents. The decrease in the median ASI from 13 to 8 between days 0 and 6 was similar among patients with positive and negative respiratory cultures. Patients with negative cultures were more likely to be off antibiotics from day 3 onward.
The results of respiratory cultures had only a small influence on antibiotics used during the treatment of HAP/VAP. The decrease in ASI for both groups suggests the integration of antibiotic stewardship principles, including de-escalation, into the care of patients with HAP/VAP.
A single spray application of a continuously active disinfectant on portable equipment resulted in significant reductions in aerobic colony counts over 7 days and in recovery of Staphylococcus aureus and enterococci: 3 of 93 cultures (3%) versus 11 of 97 (11%) and 20 of 97 (21%) in quaternary ammonium disinfectant and untreated control groups, respectively.
To assess the potential for contamination of personnel, patients, and the environment during use of contaminated N95 respirators and to compare the effectiveness of interventions to reduce contamination.
Simulation study of patient care interactions using N95 respirators contaminated with a higher and lower inocula of the benign virus bacteriophage MS2.
In total, 12 healthcare personnel performed 3 standardized examinations of mannequins including (1) control with suboptimal respirator handling technique, (2) improved technique with glove change after each N95 contact, and (3) control with 1-minute ultraviolet-C light (UV-C) treatment prior to donning. The order of the examinations was randomized within each subject. The frequencies of contamination were compared among groups. Observations and simulations with fluorescent lotion were used to assess routes of transfer leading to contamination.
With suboptimal respirator handling technique, bacteriophage MS2 was frequently transferred to the participants, mannequin, and environmental surfaces and fomites. Improved technique resulted in significantly reduced transfer of MS2 in the higher inoculum simulations (P < .01), whereas UV-C treatment reduced transfer in both the higher- and lower-inoculum simulations (P < .01). Observations and simulations with fluorescent lotion demonstrated multiple potential routes of transfer to participants, mannequin, and surfaces, including both direct contact with the contaminated respirator and indirect contact via contaminated gloves.
Reuse of contaminated N95 respirators can result in contamination of personnel and the environment even when correct technique is used. Decontamination technologies, such as UV-C, could reduce the risk for transmission.
To investigate the timing and routes of contamination of the rooms of patients newly admitted to the hospital.
Observational cohort study and simulations of pathogen transfer.
A Veterans’ Affairs hospital.
Patients newly admitted to the hospital with no known carriage of healthcare-associated pathogens.
Interactions between the participants and personnel or portable equipment were observed, and cultures of high-touch surfaces, floors, bedding, and patients’ socks and skin were collected for up to 4 days. Cultures were processed for Clostridioides difﬁcile, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant enterococci (VRE). Simulations were conducted with bacteriophage MS2 to assess plausibility of transfer from contaminated floors to high-touch surfaces and to assess the effectiveness of wearing slippers in reducing transfer.
Environmental cultures became positive for at least 1 pathogen in 10 (59%) of the 17 rooms, with cultures positive for MRSA, C. difficile, and VRE in the rooms of 10 (59%), 2 (12%), and 2 (12%) participants, respectively. For all 14 instances of pathogen detection, the initial site of recovery was the floor followed in a subset of patients by detection on sock bottoms, bedding, and high-touch surfaces. In simulations, wearing slippers over hospital socks dramatically reduced transfer of bacteriophage MS2 from the floor to hands and to high-touch surfaces.
Floors may be an underappreciated source of pathogen dissemination in healthcare facilities. Simple interventions such as having patients wear slippers could potentially reduce the risk for transfer of pathogens from floors to hands and high-touch surfaces.
Gloves and gowns are used during patient care to reduce contamination of personnel and prevent pathogen transmission.
To determine whether the use of gowns adds a substantial benefit over gloves alone in preventing patient-to-patient transfer of a viral DNA surrogate marker.
In total, 30 source patients had 1 cauliflower mosaic virus surrogate marker applied to their skin and clothing and a second to their bed rail and bedside table. Personnel caring for the source patients were randomized to wear gloves, gloves plus cover gowns, or no barrier. Interactions with up to 7 subsequent patients were observed, and the percentages of transfer of the DNA markers were compared among the 3 groups.
In comparison to the no-barrier group (57.8% transfer of 1 or both markers), there were significant reductions in transfer of the DNA markers in the gloves group (31.1% transfer; odds ratio [OR], 0.16; 95% confidence interval [CI], 0.02-0.73) and the gloves-plus-gown group (25.9% transfer; OR, 0.11; 95% CI, 0.01–0.51). The addition of a cover gown to gloves during the interaction with the source patient did not significantly reduce the transfer of the DNA marker (P = .53). During subsequent patient interactions, transfer of the DNA markers was significantly reduced if gloves plus gowns were worn and if hand hygiene was performed (P < .05).
Wearing gloves or gloves plus gowns reduced the frequency of patient-to-patient transfer of a viral DNA surrogate marker. The use of gloves plus gowns during interactions with the source patient did not reduce transfer in comparison to gloves alone.
There is controversy regarding whether the addition of cover gowns offers a substantial benefit over gloves alone in reducing personnel contamination and preventing pathogen transmission.
Simulated patient care interactions.
To evaluate the efficacy of different types of barrier precautions and to identify routes of transmission.
In randomly ordered sequence, 30 personnel each performed 3 standardized examinations of mannequins contaminated with pathogen surrogate markers (cauliflower mosaic virus DNA, bacteriophage MS2, nontoxigenic Clostridioides difficile spores, and fluorescent tracer) while wearing no barriers, gloves, or gloves plus gowns followed by examination of a noncontaminated mannequin. We compared the frequency and routes of transfer of the surrogate markers to the second mannequin or the environment.
For a composite of all surrogate markers, transfer by hands occurred at significantly lower rates in the gloves-alone group (OR, 0.02; P < .001) and the gloves-plus-gown group (OR, 0.06; P = .002). Transfer by stethoscope diaphragms was common in all groups and was reduced by wiping the stethoscope between simulations (OR, 0.06; P < .001). Compared to the no-barriers group, wearing a cover gown and gloves resulted in reduced contamination of clothing (OR, 0.15; P < .001), but wearing gloves alone did not.
Wearing gloves alone or gloves plus gowns reduces hand transfer of pathogens but may not address transfer by devices such as stethoscopes. Cover gowns reduce the risk of contaminating the clothing of personnel.
The hands of healthcare personnel are the most important source for transmission of healthcare-associated pathogens. The role of contaminated fomites such as portable equipment, stethoscopes, and clothing of personnel in pathogen transmission is unclear.
To study routes of transmission of cauliflower mosaic virus DNA markers from 31 source patients and from environmental surfaces in their rooms.
A 3-month observational cohort study.
A Veterans’ Affairs hospital.
After providing care for source patients, healthcare personnel were observed during interactions with subsequent patients. Putative routes of transmission were identified based on recovery of DNA markers from sites of contact with the patient or environment. To assess plausibility of fomite-mediated transmission, we assessed the frequency of transfer of methicillin-resistant Staphylococcus aureus (MRSA) from the skin of 25 colonized patients via gloved hands versus fomites.
Of 145 interactions involving contact with patients and/or the environment, 41 (28.3%) resulted in transfer of 1 or both DNA markers to the patient and/or the environment. The DNA marker applied to patients’ skin and clothing was transferred most frequently by stethoscopes, hands, and portable equipment, whereas the marker applied to environmental surfaces was transferred only by hands and clothing. The percentages of MRSA transfer from the skin of colonized patients via gloved hands, stethoscope diaphragms, and clothing were 52%, 40%, and 48%, respectively.
Fomites such as stethoscopes, clothing, and portable equipment may be underappreciated sources of pathogen transmission. Simple interventions such as decontamination of fomites between patients could reduce the risk for transmission.