Second monovalent SARS-CoV-2 mRNA booster restores Omicron-specific neutralizing activity in both nursing home residents and health care workers

We examined whether the second monovalent SARS-CoV-2 mRNA booster increased antibody levels and their neutralizing activity to Omicron variants in nursing home residents (NH) residents and healthcare workers (HCW). We sampled 376 NH residents and 63 HCW after primary mRNA vaccination, first and second boosters, for antibody response and pseudovirus neutralization assay against SARS-CoV-2 wild-type (WT) (Wuhan-Hu-1) strain, Omicron BA.1 and BA.5 variants. Antibody levels and neutralizing activity progressively increased with each booster but subsequently waned over 3-6 months. NH residents, both those without and with prior infection, had a robust geometric mean fold rise (GMFR) of 8.1 (95% CI 4.4, 14.8) and 7.8 (95% CI 4.8, 12.9) respectively in Omicron-BA.1 subvariant specific neutralizing antibody levels following the second booster vaccination (p<0.001). These results support the ongoing efforts to ensure that both NH residents and HCW are up-to-date on recommended SARS-CoV-2 vaccine booster doses.

Effectiveness of commercial portable air cleaners and a do-it-yourself minimum efficiency reporting value (MERV)-13 filter box fan air cleaner in reducing aerosolized bacteriophage MS2.

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.

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

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.

Evaluation of Ultraviolet-C Light for Rapid Decontamination of Airport Security Bins in the Era of SARS-CoV-2.

BACKGROUND: Contaminated surfaces are a potential source for spread of respiratory viruses including SARS-CoV-2. Ultraviolet-C (UV-C) light is effective against RNA and DNA viruses and could be useful for decontamination of high-touch fomites that are shared by multiple users. METHODS: A modification of the American Society for Testing and Materials standard quantitative carrier disk test method (ASTM E-2197-11) was used to examine the effectiveness of UV-C light for rapid decontamination of plastic airport security bins inoculated at 3 sites with methicillin-resistant Staphylococcus aureus (MRSA) and bacteriophages MS2, PhiX174, and Phi6, an enveloped RNA virus used as a surrogate for coronaviruses. Reductions of 3 log10 on inoculated plastic bins were considered effective for decontamination. RESULTS: UV-C light administered as 10-, 20-, or 30-second cycles in proximity to a plastic bin reduced contamination on each of the test sites, including vertical and horizontal surfaces. The 30-second cycle met criteria for decontamination of all 3 test sites for all the test organisms except bacteriophage MS2 which was reduced by greater than 2 log10 PFU at each site. CONCLUSIONS: UV-C light is an attractive technology for rapid decontamination of airport security bins. Further work is needed to evaluate the utility of UV-C light in real-world settings and to develop methods to provide automated movement of bins through a UV-C decontamination process.

Low rates of antibiotics prescribed during telehealth primary-care visits persisted during the coronavirus disease 2019 (COVID-19) pandemic.

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.

Neither Race nor Ethnicity Impact the Mortality of Residents of Veterans Affairs Community Living Center With COVID-19.

OBJECTIVES: COVID-19 disproportionately affected nursing home residents and people from racial and ethnic minorities in the United States. Nursing homes in the Veterans Affairs (VA) system, termed Community Living Centers (CLCs), belong to a national managed care system. In the period prior to the availability of vaccines, we examined whether residents from racial and ethnic minorities experienced disparities in COVID-19 related mortality. DESIGN: Retrospective cohort study. SETTING AND PARTICIPANTS: Residents at 134 VA CLCs from April 14 to December 10, 2020. METHODS: We used the VA Corporate Data Warehouse to identify VA CLC residents with a positive SARS-CoV-2 polymerase chain reaction test during or 2 days prior to their admission and without a prior case of COVID-19. We assessed age, self-reported race/ethnicity, frailty, chronic medical conditions, Charlson comorbidity index, the annual quarter of the infection, and all-cause 30-day mortality. We estimated odds ratios and 95% confidence intervals of all-cause 30-day mortality using a mixed-effects multivariable logistic regression model. RESULTS: During the study period, 1133 CLC residents had an index positive SARS-CoV-2 test. Mortality at 30 days was 23% for White non-Hispanic residents, 15% for Black non-Hispanic residents, 10% for Hispanic residents, and 16% for other residents. Factors associated with increased 30-day mortality were age ≥70 years, Charlson comorbidity index ≥6, and a positive SARS-CoV-2 test between April 14 and June 30, 2020. Frailty, Black race, and Hispanic ethnicity were not independently associated with an increased risk of 30-day mortality. CONCLUSIONS AND IMPLICATIONS: Among a national cohort of VA CLC residents with COVID-19, neither Black race nor Hispanic ethnicity had a negative impact on survival. Further research is needed to determine factors within the VA health care system that mitigate the influence of systemic racism on COVID-19 outcomes in US nursing homes.

SARS-CoV-2 Antibody Responses to the Ancestral SARS-CoV-2 Strain and Omicron BA.1 and BA.4/BA.5 Variants in Nursing Home Residents After Receipt of Bivalent COVID-19 Vaccine - Ohio and Rhode Island, September-November 2022.

Introduction of monovalent COVID-19 mRNA vaccines in late 2020 helped to mitigate disproportionate COVID-19-related morbidity and mortality in U.S. nursing homes (1); however, reduced effectiveness of monovalent vaccines during the period of Omicron variant predominance led to recommendations for booster doses with bivalent COVID-19 mRNA vaccines that include an Omicron BA.4/BA.5 spike protein component to broaden immune response and improve vaccine effectiveness against circulating Omicron variants (2). Recent studies suggest that bivalent booster doses provide substantial additional protection against SARS-CoV-2 infection and severe COVID-19-associated disease among immunocompetent adults who previously received only monovalent vaccines (3).* The immunologic response after receipt of bivalent boosters among nursing home residents, who often mount poor immunologic responses to vaccines, remains unknown. Serial testing of anti-spike protein antibody binding and neutralizing antibody titers in serum collected from 233 long-stay nursing home residents from the time of their primary vaccination series and including any subsequent booster doses, including the bivalent vaccine, was performed. The bivalent COVID-19 mRNA vaccine substantially increased anti-spike and neutralizing antibody titers against Omicron sublineages, including BA.1 and BA.4/BA.5, irrespective of previous SARS-CoV-2 infection or previous receipt of 1 or 2 booster doses. These data, in combination with evidence of low uptake of bivalent booster vaccination among residents and staff members in nursing homes (4), support the recommendation that nursing home residents and staff members receive a bivalent COVID-19 booster dose to reduce associated morbidity and mortality (2).

Evaluation of Interventions to Improve Ventilation in Households to Reduce Risk for Transmission of Severe Acute Respiratory Syndrome Coronavirus 2.

Background: Inadequate ventilation may contribute to the high risk for household transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods: We evaluated the effectiveness of several interventions recommended to improve ventilation in households. In 7 residential homes, carbon dioxide monitoring was conducted to assess ventilation in occupied open areas such as family rooms and in bedrooms and/or offices. Carbon dioxide levels above 800 parts per million (ppm) were considered an indicator of suboptimal ventilation for the number of people present. In 1 of the 7 homes, various interventions to improve ventilation or to filter air were assessed in a kitchen area by measuring clearance of aerosol particles produced using an aerosol-based spray system and carbon dioxide generated by cooking with a gas stove. Results: Carbon dioxide levels rose above 800 ppm in bedrooms and offices with 2 occupants when windows and doors were closed and in open areas during gatherings of 5 to 10 people; carbon dioxide levels decreased when windows or doors were opened. Clearance of carbon dioxide and aerosol particles significantly increased with interventions including running fans, operating portable air cleaners, and opening windows, particularly when there was a noticeable breeze or when a window fan was used to blow contaminated air outside. Conclusion: In households, several measures to improve ventilation or air filtration were effective in reducing carbon dioxide accumulation or enhancing clearance of carbon dioxide and aerosol particles. Studies are needed to determine if interventions to improve ventilation can reduce the risk for airborne transmission of SARS-CoV-2 in households.

Real-World Evidence on the Effectiveness of Plexiglass Barriers in Reducing Aerosol Exposure.

Reprinted with permission, Cleveland Clinic Foundation ©2022. All Rights Reserved. Background: Barriers are commonly installed in workplace situations where physical distancing cannot be maintained to reduce the risk for transmission of respiratory viruses. Although some types of barriers have been shown to reduce exposure to aerosols in laboratory-based testing, limited information is available on the efficacy of barriers in real-world settings. Methods: In an acute care hospital, we tested the effectiveness of in-use plexiglass barriers in reducing exposure of staff to aerosolized particles. A nebulizer was used to release 5% NaCl aerosol 1 meter from staff members with and without the barrier positioned between the point of aerosol release and the hospital staff. Particle counts on the staff side of the barrier were measured using a 6-channel particle counter. A condensed moisture (fog) generating device was used to visualize the airflow patterns. Results: Of 13 in-use barriers tested, 6 (46%) significantly reduced aerosol particle counts detected behind the barrier, 6 (46%) reduced particle counts to a modest, non-significant degree, and 1 (8%) significantly increased particle counts behind the barrier. Condensed moisture fog accumulated in the area where staff were seated behind the barrier that increased particle exposure, but not behind the other barriers. After repositioning the ineffective barrier, the condensed moisture fog no longer accumulated behind the barrier and aerosol exposure was reduced. Conclusion: In real-world settings, plexiglass barriers vary widely in effectiveness in reducing staff exposure to aerosols, and some barriers may increase risk for exposure if not positioned correctly. Devices that visualize airflow patterns may be useful as simple tools to assess barriers.

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. 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. RESULTS: 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. CONCLUSION: 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.

COVID-19 vaccine booster dose needed to achieve Omicron-specific neutralisation in nursing home residents.

BACKGROUND: Nursing home (NH) residents have borne a disproportionate share of SARS-CoV-2 morbidity and mortality. Vaccines have limited hospitalisation and death from earlier variants in this vulnerable population. With the rise of Omicron and future variants, it is vital to sustain and broaden vaccine-induced protection. We examined the effect of boosting with BNT162b2 mRNA vaccine on humoral immunity and Omicron-specific neutralising activity among NH residents and healthcare workers (HCWs). METHODS: We longitudinally enrolled 85 NH residents (median age 77) and 48 HCWs (median age 51), and sampled them after the initial vaccination series; and just before and 2 weeks after booster vaccination. Anti-spike, anti-receptor binding domain (RBD) and neutralisation titres to the original Wuhan strain and neutralisation to the Omicron strain were obtained. FINDINGS: Booster vaccination significantly increased vaccine-specific anti-spike, anti-RBD, and neutralisation levels above the pre-booster levels in NH residents and HCWs, both in those with and without prior SARS-CoV-2 infection. Omicron-specific neutralisation activity was low after the initial 2 dose series with only 28% of NH residents' and 28% HCWs' titres above the assay's lower limit of detection. Omicron neutralising activity following the booster lifted 86% of NH residents and 93% of HCWs to the detectable range. INTERPRETATION: With boosting, the vast majority of HCWs and NH residents developed detectable Omicron-specific neutralising activity. These data provide immunologic evidence that strongly supports booster vaccination to broaden neutralising activity and counter waning immunity in the hope it will better protect this vulnerable, high-risk population against the Omicron variant. FUNDING: NIH AI129709-03S1, U01 CA260539-01, CDC 200-2016-91773, and VA BX005507-01.

Significant Reduction in Vaccine-Induced Antibody Levels and Neutralization Activity Among Healthcare Workers and Nursing Home Residents 6 Months Following Coronavirus Disease 2019 BNT162b2 mRNA Vaccination.

Antibody decline occurred from 2 weeks to 6 months post-BNT162b2 mRNA vaccination in nursing home (NH) residents and healthcare workers. Antispike, receptor-binding domain, and neutralization levels dropped >81% irrespective of prior infection. Notably, 69% of infection-naive NH residents had neutralizing antibodies at or below the assay's limit of detection.

Impact of fever thresholds in detection of COVID-19 in Department of Veterans Affairs Community Living Center residents.

BACKGROUND: Among nursing home residents, for whom age and frailty can blunt febrile responses to illness, the temperature used to define fever can influence the clinical recognition of COVID-19 symptoms. To assess the potential for differences in the definition of fever to characterize nursing home residents with COVID-19 infections as symptomatic, pre-symptomatic, or asymptomatic, we conducted a retrospective study on a national cohort of Department of Veterans Affairs (VA) Community Living Center (CLC) residents tested for SARS-CoV-2. METHODS: Residents with positive SARS-CoV-2 tests were classified as asymptomatic if they did not experience any symptoms, and as symptomatic or pre-symptomatic if the experienced a fever (>100.4°F) before or following a positive SARS-CoV-2 test, respectively. All-cause 30-day mortality was assessed as was the influence of a lower temperature threshold (>99.0°F) on classification of residents with positive SARS-CoV-2 tests. RESULTS: From March 2020 through November 2020, VA CLCs tested 11,908 residents for SARS-CoV-2 using RT-PCR, with a positivity of rate of 13% (1557). Among residents with positive tests and using >100.4°F, 321 (21%) were symptomatic, 425 (27%) were pre-symptomatic, and 811 (52%) were asymptomatic. All-cause 30-day mortality among residents with symptomatic and pre-symptomatic COVID-19 infections was 24% and 26%, respectively, while those with an asymptomatic infection had mortality rates similar to residents with negative SAR-CoV-2 tests (10% and 5%, respectively). Using >99.0°F would have increased the number of residents categorized as symptomatic at the time of testing from 321 to 773. CONCLUSIONS: All-cause 30-day mortality was similar among VA CLC residents with symptomatic or pre-symptomatic COVID-19 infection, and lower than rates reported in non-VA nursing homes. A lower temperature threshold would increase the number of residents recognized as having symptomatic infection, potentially leading to earlier detection and more rapid implementation of therapeutic interventions and infection prevention and control measures.

Evaluation of an electrostatic spray disinfectant technology for rapid decontamination of portable equipment and large open areas in the era of SARS-CoV-2.

In the setting of the coronavirus disease 2019 pandemic, efficient methods are needed to decontaminate shared portable devices and large open areas such as waiting rooms. We found that wheelchairs, portable equipment, and waiting room chairs were frequently contaminated with potential pathogens. After minimal manual precleaning of areas with visible soiling, application of a dilute sodium hypochlorite disinfectant using an electrostatic sprayer provided rapid and effective decontamination and eliminated the benign virus bacteriophage MS2 from inoculated surfaces.