Bivalent and Monovalent SARS-CoV-2 Variant Vaccine Boosters Improve coverage of the known Antigenic Landscape: Results of the COVID-19 Variant Immunologic Landscape (COVAIL) Trial (preprint)

Vaccine protection against COVID-19 wanes over time and has been impacted by the emergence of new variants with increasing escape of neutralization. The COVID-19 Variant Immunologic Landscape (COVAIL) randomized clinical trial (clinicaltrials.gov NCT 05289037) compares the breadth, magnitude and durability of antibody responses induced by a second COVID-19 vaccine boost with mRNA (Moderna mRNA-1273 and Pfizer-BioNTech BNT162b2), or adjuvanted recombinant protein (Sanofi CoV2 preS DTM-AS03) monovalent or bivalent vaccine candidates targeting ancestral and variant SARS-CoV-2 spike antigens (Beta, Delta and Omicron BA.1). We found that boosting with a variant strain is not associated with loss in neutralization against the ancestral strain. However, while variant vaccines compared to the prototype/wildtype vaccines demonstrated higher neutralizing activity against Omicron BA.1 and BA.4/5 subvariants for up to 3 months after vaccination, neutralizing activity was lower for more recent Omicron subvariants. Our study, incorporating both antigenic distances and serologic landscapes, can provide a framework for objectively guiding decisions for future vaccine updates.

Comparative Effectiveness of Standard and Contingency-based Cleaning in Acute and Long-Term Care Facilities amidst Staff Shortages and a COVID-19 Surge (preprint)

Background: Cleanliness of hospital surfaces helps prevent healthcare-associated infections, but larger evaluations of the effectiveness of various cleaning strategies during SARS-CoV-2 surges and worker shortages are scarce. Methods: In an acute care hospital (ACH) and a long-term care facility (LTCF), 417 surfaces were tested for SARS-CoV-2 and adenosine triphosphate before and after various cleaning strategies, including ultraviolet light (UV-C), electrostatic spraying, and room fogging. Results: ACH surface contamination differed among outbreak and non-outbreak wards (p = 0.001). RNA was detected on 66% of surfaces before cleaning and on 23% of those surfaces immediately after terminal cleaning, for a 65% post-cleaning reduction (p = 0.001). UV-C resulted in an 87% reduction (p = 0.023), while spraying with electrostatic bleach resulted in a 47% reduction (p = 0.010). LTCF contamination rates differed between the dementia, rehabilitation, and the residential units (p = 0.005). 67% of surfaces had RNA after room fogging without terminal-style wiping. Fogging with wiping led to an 11% reduction in the proportion of positive surfaces. Discussion: Baseline contamination varied by type of unit and outbreak conditions, but not facility type. Removal of viral RNA varied according to strategy. Unlike previous reports, time spent cleaning was associated with cleaning thoroughness.

Emergence of the E484K Mutation in SARS-CoV-2 Lineage B.1.1.220 in Upstate New York (preprint)

Ongoing surveillance detected a SARS-CoV-2 B.1.1.220 variant carrying the E484K substitution in four patients from a hospital network in upstate New York. Patients reported no travel history and shared no obvious epidemiological linkage. A search of online databases identified 12 additional B.1.1.220 with E484K, all of which were detected in New York since December 2020. Detailed genomic analyses suggests that the mutation has emerged independently in at least two different B.1.1.220 strains in this region.