Evaluating immunity to SARS-CoV-2 in nursing home residents using saliva IgG.

BACKGROUND: SARS-CoV-2 circulating variants coupled with waning immunity pose a significant threat to the long-term care (LTC) population. Our objective was to measure salivary IgG antibodies in residents and staff of an LTC facility to (1) evaluate IgG response in saliva post-natural infection and vaccination and (2) assess its feasibility to describe the seroprevalence over time. METHODS: We performed salivary IgG sampling of all residents and staff who agreed to test in a 150-bed skilled nursing facility during three seroprevalence surveys between October 2020 and February 2021. The facility had SARS-CoV-2 outbreaks in May 2020 and November 2020, when 45 of 138 and 37 of 125 residents were infected, respectively; they offered two Federal vaccine clinics in January 2021. We evaluated quantitative IgG in saliva to the Nucleocapsid (N), Spike (S), and Receptor-binding domain (RBD) Antigens of SARS-CoV-2 over time post-infection and post-vaccination. RESULTS: One hundred twenty-four residents and 28 staff underwent saliva serologic testing on one or more survey visits. Over three surveys, the SARS-CoV-2 seroprevalence at the facility was 49%, 64%, and 81%, respectively. IgG to S, RBD, and N Antigens all increased post infection. Post vaccination, the infection naïve group did not have a detectable N IgG level, and N IgG levels for the previously infected did not increase post vaccination (p < 0.001). Fully vaccinated subjects with prior COVID-19 infection had significantly higher RBD and S IgG responses compared with those who were infection-naïve prior to vaccination (p < 0.001 for both). CONCLUSIONS: Positive SARS-COV-2 IgG in saliva was concordant with prior infection (Anti N, S, RBD) and vaccination (Anti S, RBD) and remained above positivity threshold for up to 9 months from infection. Salivary sampling is a non-invasive method of tracking immunity and differentiating between prior infection and vaccination to inform the need for boosters in LTC residents and staff.

The case for wearable proximity devices to inform physical distancing among healthcare workers.

OBJECTIVE: Despite the importance of physical distancing in reducing SARS-CoV-2 transmission, this practice is challenging in healthcare. We piloted use of wearable proximity beacons among healthcare workers (HCWs) in an inpatient unit to highlight considerations for future use of trackable technologies in healthcare settings. MATERIALS AND METHODS: We performed a feasibility pilot study in a non-COVID adult medical unit from September 28 to October 28, 2020. HCWs wore wearable proximity beacons, and interactions defined as <6 feet for ≥5 s were recorded. Validation was performed using direct observations. RESULTS: A total of 6172 close proximity interactions were recorded, and with the removal of 2033 false-positive interactions, 4139 remained. The highest proportion of interactions occurred between 7:00 Am-9:00 Am. Direct observations of HCWs substantiated these findings. DISCUSSION: This pilot study showed that wearable beacons can be used to monitor and quantify HCW interactions in inpatient settings. CONCLUSION: Technology can be used to track HCW physical distancing.

Barriers to physical distancing among healthcare workers on an academic hospital unit during the coronavirus disease 2019 (COVID-19) pandemic.

BACKGROUND: Physical distancing among healthcare workers (HCWs) is an essential strategy in preventing HCW-to-HCWs transmission of severe acute respiratory coronavirus virus 2 (SARS-CoV-2). OBJECTIVE: To understand barriers to physical distancing among HCWs on an inpatient unit and identify strategies for improvement. DESIGN: Qualitative study including observations and semistructured interviews conducted over 3 months. SETTING: A non-COVID-19 adult general medical unit in an academic tertiary-care hospital. PARTICIPANTS: HCWs based on the unit. METHODS: We performed a qualitative study in which we (1) observed HCW activities and proximity to each other on the unit during weekday shifts July-October 2020 and (2) conducted semi-structured interviews of HCWs to understand their experiences with and perspectives of physical distancing in the hospital. Qualitative data were coded based on a human-factors engineering model. RESULTS: We completed 25 hours of observations and 20 HCW interviews. High-risk interactions often occurred during handoffs of care at shift changes and patient rounds, when HCWs gathered regularly in close proximity for at least 15 minutes. Identified barriers included spacing and availability of computers, the need to communicate confidential patient information, and the desire to maintain relationships at work. CONCLUSIONS: Physical distancing can be improved in hospitals by restructuring computer workstations, work rooms, and break rooms; applying visible cognitive aids; adapting shift times; and supporting rounds and meetings with virtual conferencing. Additional strategies to promote staff adherence to physical distancing include rewarding positive behaviors, having peer leaders model physical distancing, and encouraging additional safe avenues for social connection at a safe distance.

Prevalence of Co-infection at the Time of Hospital Admission in COVID-19 Patients, A Multicenter Study.

BACKGROUND: Bacterial infections may complicate viral pneumonias. Recent reports suggest that bacterial co-infection at time of presentation is uncommon in coronavirus disease 2019 (COVID-19); however, estimates were based on microbiology tests alone. We sought to develop and apply consensus definitions, incorporating clinical criteria to better understand the rate of co-infections and antibiotic use in COVID-19. METHODS: A total of 1016 adult patients admitted to 5 hospitals in the Johns Hopkins Health System between March 1, 2020, and May 31, 2020, with COVID-19 were evaluated. Adjudication of co-infection using definitions developed by a multidisciplinary team for this study was performed. Both respiratory and common nonrespiratory co-infections were assessed. The definition of bacterial community-acquired pneumonia (bCAP) included proven (clinical, laboratory, and radiographic criteria plus microbiologic diagnosis), probable (clinical, laboratory, and radiographic criteria without microbiologic diagnosis), and possible (not all clinical, laboratory, and radiographic criteria met) categories. Clinical characteristics and antimicrobial use were assessed in the context of the consensus definitions. RESULTS: Bacterial respiratory co-infections were infrequent (1.2%); 1 patient had proven bCAP, and 11 (1.1%) had probable bCAP. Two patients (0.2%) had viral respiratory co-infections. Although 69% of patients received antibiotics for pneumonia, the majority were stopped within 48 hours in patients with possible or no evidence of bCAP. The most common nonrespiratory infection was urinary tract infection (present in 3% of the cohort). CONCLUSIONS: Using multidisciplinary consensus definitions, proven or probable bCAP was uncommon in adults hospitalized due to COVID-19, as were other nonrespiratory bacterial infections. Empiric antibiotic use was high, highlighting the need to enhance antibiotic stewardship in the treatment of viral pneumonias.