REALM Project

Research briefing: Vaccines, variants, and ventilation

18 November 2021

This briefing, prepared by researchers at Battelle, is intended to provide timely information about SARS-CoV-2 vaccines and variants to libraries, archives, museums (LAMs), and their stakeholders. This is a review of scientific literature published through 1 November 2021, and should be used in conjunction with other timely resources to ensure decision-making in LAMs reflects the latest scientific understanding. Continual re-evaluation of SARS-CoV-2 policies is highly recommended as new scientific discoveries are published. 

Research questions

• What implications does SARS-CoV-2 vaccination in the United States have for public health interventions and policies, especially related to indoor environments?
• What differences have been found for SARS-CoV-2 variants (compared to the original strain) in the United States in terms of spread, transmissibility, surface attenuation, and effectiveness of public health interventions?
• What effects do ventilation and ventilation-based interventions (e.g., heating, ventilation, and air conditioning systems (HVAC)) have on the spread of SARS-CoV-2 in indoor environments?

HIGHLIGHTS

• Ventilation: A study analyzing the impact of humidification on SARS-CoV-2 transmission risk found that humidifying a space to 40-60% relative humidity is unlikely to significantly reduce transmission risk.
• Variants: One study of breakthrough infections with the delta variant among vaccinated healthcare workers found these infections were driven by social gatherings and household exposures where people were largely unmasked.
• Vaccines: People 18 years and older who received the Johnson & Johnson vaccine should receive a booster shot at least two months after their primary vaccine dose.

Notes for the reader

As you read this briefing, keep in mind a few key points:

1. The research and information captured in the findings include both peer-reviewed and non-peer-reviewed studies. In the interest of publishing emerging research related to the COVID-19 pandemic as quickly as possible, publication has been expedited rather than waiting for time-intensive peer review.
2. The review includes findings for industries, such as health care, that operate under considerably different constraints and risk factors than do libraries, archives, and museums (LAMs). However, it was important to consider a broad range of available research to determine what may be applicable to LAM operations and identify what research gaps exist. The research captured in the review does not represent recommendations or guidance for LAMs.
3. Additional literature reviews and research briefings are available from REALM.
   
4. A helpful resource for those interested in tracking the "known unknowns" about this virus is the DHS Master Question List for COVID-19 (caused by SARS-CoV-2).
   

Download the research briefing