StopCOVID@UMD Publications

Infectious Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in Exhaled Aerosols and Efficacy of Masks During Early Mild Infection, published in Clinical Infectious Diseases (2021). Link to this manuscript: https://doi.org/10.1093/cid/ciab797

1. • Cases exhale infectious viral aerosols.

   • SARS-CoV-2 is evolving toward more efficient airborne transmission.

   • Loose-fitting masks significantly but moderately reduce viral RNA aerosol.

   • Tight-fitting masks or respirators and ventilation/air cleaning are essential for worker protection in public-facing or crowded indoor workplaces.

   • Please also check out the article at Science News that talks about our results: https://www.sciencenews.org/article/covid-coronavirus-aerosol-droplets-airborne-evolution
     
     

Comparison of Saliva and Midturbinate Swabs for Detection of SARS-CoV-2, published in Microbiology Spectrum (2022). Link to this manuscript: https://doi.org/10.1128/spectrum.00128-22

1. • We compared detection of SARS-CoV-2 in saliva samples to nasal swab (mid-turbinate) samples. 

   • We found that saliva-based PCR is more sensitive than nasal swab-based PCR in detecting SARS-CoV-2 during the presymptomatic period.

   • Since saliva samples cost less, are more acceptable to the general public, and are less of a risk to health care workers, our findings support the use of saliva over naval swabs, in identifying presymptomatic infection by SARS-CoV-2.
     
     

Exhaled Breath Aerosol Shedding of Highly Transmissible Versus Prior Severe Acute Respiratory Syndrome Coronavirus 2 Variants, published in Clinical Infectious Diseases (2022). Link to this manuscript: https://doi.org/10.1093/cid/ciac846

1. • We measured the infectivity and rate of SARS-CoV-2 shedding into exhaled breath aerosols by individuals during the Delta and Omicron waves, and compared those rates with those of prior SARS-CoV-2 variants from our previously published work.

   • We found that Alpha, Delta, and Omicron cases shed significantly more viral RNA in exhaled breath, compared to the earlier SARS-CoV-2 strains.

   • Alpha, Delta, and Omicron independently evolved high viral aerosol shedding phenotypes, demonstrating convergent evolution. Vaccinated and boosted cases can shed infectious SARS-CoV-2 via exhaled breath. These findings support a dominant role of infectious aerosols in transmission of SARS-CoV-2. 

Thanks to everyone who took part in this part of the study!!!