Incubation period of infection in hospitalized patients and long-term care facility residents: a prospective cohort study.

Background: The incubation period for infection (CDI) is generally considered to be less than 1 week, but some recent studies suggest that prolonged carriage prior to disease onset may be common.

Objective: To estimate the incubation period for patients developing CDI after initial negative cultures.

Methods: In 3 tertiary care medical centers, we conducted a cohort study to identify hospitalized patients and long-term care facility residents with negative initial cultures for followed by a diagnosis of CDI with or without prior detection of carriage.

Dissemination of methicillin-resistant Staphylococcus aureus and bacteriophage MS2 from floors in long-term care facility resident rooms.

We demonstrated that methicillin-resistant Staphylococcus aureus (MRSA) contamination on floors in the rooms of colonized long-term care facility residents was frequently transferred by shoes to adjacent patient rooms. A benign virus inoculated onto the floor was transferred to floors and high-touch surfaces in adjacent rooms and the nursing station. These results suggest that shoes may serve as a vector for dissemination of health care-associated pathogens from rooms of MRSA-colonized patients.

A randomized trial to determine whether wearing slippers reduces transfer of bacteriophage MS2 from floors to patients and surfaces in hospital rooms.

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.Registration: ClinicalTrials.

Airflow Patterns in Double-Occupancy Patient Rooms May Contribute to Roommate-to-Roommate Transmission of Severe Acute Respiratory Syndrome Coronavirus 2.

Background: Hospitalized patients are at risk to acquire severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from roommates with unrecognized coronavirus disease 2019 (COVID-19). We hypothesized that airflow patterns might contribute to SARS-CoV-2 transmission in double-occupancy patient rooms.

Methods: A device emitting condensed moisture was used to identify airflow patterns in double-occupancy patient rooms.

Planes, Trains, and Automobiles: Use of Carbon Dioxide Monitoring to Assess Ventilation During Travel.

Background: Travel poses a risk for transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other respiratory viruses. Poorly ventilated indoor settings pose a particularly high risk for transmission.

Methods: We used carbon dioxide measurements to assess adequacy of ventilation during 5 trips that included air travel.

Use of carbon dioxide measurements to assess ventilation in an acute care hospital.

Poorly ventilated indoor spaces pose a risk for airborne transmission of SARS-CoV-2. We measured carbon dioxide levels in a multiple areas in an acute care hospital to assess the adequacy of ventilation. Carbon dioxide levels remained below 800 parts per million in most areas but exceeded this level in a small conference room with 8 occupants, an office with 3 occupants, and a bathroom with 2 occupants.

Use of cauliflower mosaic virus DNA markers to assess the potential for pathogen transmission from physicians' white coats.

In an observational study, the sleeves and pockets of physicians' white coats often directly or indirectly contacted patients and environmental surfaces. DNA markers on the sleeves or pockets were frequently transferred to surfaces and patients. These findings suggest that contaminated white coats have the potential to contribute to pathogen transmission.

Transfer of methicillin-resistant by fist bump versus elbow bump.

For 40 patients with methicillin-resistant (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.

Evaluation of a continuously active disinfectant for decontamination of portable medical equipment.

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.

A simulation study to evaluate contamination during reuse of N95 respirators and effectiveness of interventions to reduce contamination.

Objective: 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.

Design: Simulation study of patient care interactions using N95 respirators contaminated with a higher and lower inocula of the benign virus bacteriophage MS2.

Methods: 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.

Shedding of methicillin-resistant Staphylococcus aureus and multidrug-resistant gram-negative bacilli during outpatient appointments and procedures outside hospital rooms.

Background: Limited information is available on the frequency of and risk factors for shedding of health care-associated pathogens in settings outside patient rooms.

Methods: We conducted a cohort study of hospitalized or recently discharged patients with methicillin-resistant Staphylococcus aureus (MRSA) (N = 39) or multidrug-resistant gram-negative bacilli (MDR-GNB) (N = 11) colonization to determine the frequency of environmental shedding during appointments outside hospital rooms or during outpatient clinic visits. Chi-square tests were performed to identify patient-level factors associated with environmental shedding.

Environmental Contamination of Contact Precaution and Non-Contact Precaution Patient Rooms in Six Acute Care Facilities.

Background: Environmental contamination is an important source of hospital multidrug-resistant organism (MDRO) transmission. Factors such as patient MDRO contact precautions (CP) status, patient proximity to surfaces, and unit type likely influence MDRO contamination and bacterial bioburden levels on patient room surfaces. Identifying factors associated with environmental contamination in patient rooms and on shared unit surfaces could help identify important environmental MDRO transmission routes.

Timing and route of contamination of hospitalized patient rooms with healthcare-associated pathogens.

Objective: To investigate the timing and routes of contamination of the rooms of patients newly admitted to the hospital.

Design: Observational cohort study and simulations of pathogen transfer.

Setting: A Veterans' Affairs hospital.

Effectiveness of barrier precautions for prevention of patient-to-patient transfer of a viral DNA surrogate marker.

Background: Gloves and gowns are used during patient care to reduce contamination of personnel and prevent pathogen transmission.

Objective: 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.

Methods: 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.

Use of simulations to evaluate the effectiveness of barrier precautions to prevent patient-to-patient transfer of healthcare-associated pathogens.

Background: 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.

Design: Simulated patient care interactions.

Objective: To evaluate the efficacy of different types of barrier precautions and to identify routes of transmission.

Use of viral DNA surrogate markers to study routes of transmission of healthcare-associated pathogens.

Background: 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.

Objective: To study routes of transmission of cauliflower mosaic virus DNA markers from 31 source patients and from environmental surfaces in their rooms.

Shedding of multidrug-resistant gram-negative bacilli by colonized patients during procedures and patient care activities.

Background: Medical procedures and patient care activities may facilitate environmental shedding of health care-associated pathogens.

Methods: We conducted a cohort study of hospitalized patients in contact precautions for carriage of extended-spectrum beta-lactamase (ESBL)-producing gram-negative bacilli (N = 38) or carbapenem-resistant gram-negative bacilli (CR-GNB) (N = 22) to determine the frequency of environmental shedding during procedures and care activities. Perirectal, wound, and skin were cultured for ESBL-producing and CR-GNB.

Transfer of methicillin-resistant by fist bump versus handshake.

For patients with methicillin-resistant Staphylococcus aureus (MRSA) colonization, a traditional fist-bump greeting did not significantly reduce MRSA transfer in comparison to a handshake. However, transfer was reduced with a modified fist bump that minimized the surface area of contact and when hand hygiene was performed before the handshake.

Efficacy of a stewardship intervention focused on reducing unnecessary use of non- antibiotics in patients with infection.

In a tertiary-care hospital and affiliated long-term care facility, a stewardship intervention focused on patients with Clostridioides difficile infection (CDI) was associated with a significant reduction in unnecessary non-CDI antibiotic therapy. However, there was no significant reduction in total non-CDI therapy or in the frequency of CDI recurrence.

Efficacy of a novel ultraviolet light-emitting diode device for decontamination of shared pens in a health care setting.

Shared pens and styluses are a potential source for transmission of health care-associated pathogens and respiratory viruses in health care facilities. A novel ultraviolet light-emitting diode device was effective in reducing bacteria and viruses inoculated on pens and in reducing methicillin-resistant Staphylococcus aureus transferred to pens by colonized patients. The device could be useful in reducing the risk of transmission of pathogens by shared writing utensils.