Transmission Potential of Vaccinated and Unvaccinated Persons By Brian Simpson

A pandemic of the unvaccinated? Well, that is not consistent with surging Covid infections in highly vaccinated populations, covered in past blog posts. However, the paper by Salvatore (et al.), reports on the study of the transmission potential  of vaccinated and unvaccinated prisoners, with respect to the Delta variant of SARS-CoV-2. It was found that “vaccinated persons who become infected with SARS-CoV-2 to be no less infectious than unvaccinated persons.” I visited my doctor today who wanted me to be jabbed with Pfizer, and I quoted this study. His reply was that at least the vaccines lessen effects. Maybe, but we are getting into headache powder and placebo territory, are we not?

https://www.medrxiv.org/content/10.1101/2021.11.12.21265796v1.full

“Transmission potential of vaccinated and unvaccinated persons infected with the SARS-CoV-2 Delta variant in a federal prison, July—August 2021”

Phillip P. Salvatore, Christine C. Lee, Sadia Sleweon, David W. McCormick, Lavinia Nicolae, Kristen Knipe, Thomas Dixon, Robert Banta, Isaac Ogle, Cristen Young, Charles Dusseau, Shawn Salmonson, Charles Ogden, Eric Godwin, TeCora Ballom, Tara Ross, Nhien Tran Wynn, Ebenezer David, Theresa K. Bessey, Gimin Kim, Suganthi Suppiah, Azaibi Tamin, Jennifer L. Harcourt, Mili Sheth, Luis Lowe, Hannah Browne, Jacqueline E. Tate, Hannah L. Kirking, Liesl M. Hagan

doi: https://doi.org/10.1101/2021.11.12.21265796

Abstract

Background The extent to which vaccinated persons who become infected with SARS-CoV-2 contribute to transmission is unclear. During a SARS-CoV-2 Delta variant outbreak among incarcerated persons with high vaccination rates in a federal prison, we assessed markers of viral shedding in vaccinated and unvaccinated persons.

Methods Consenting incarcerated persons with confirmed SARS-CoV-2 infection provided mid-turbinate nasal specimens daily for 10 consecutive days and reported symptom data via questionnaire. Real-time reverse transcription-polymerase chain reaction (RT-PCR), viral whole genome sequencing, and viral culture was performed on these nasal specimens. Duration of RT-PCR positivity and viral culture positivity was assessed using survival analysis.

Results A total of 978 specimens were provided by 95 participants, of whom 78 (82%) were fully vaccinated and 17 (18%) were not fully vaccinated. No significant differences were detected in duration of RT-PCR positivity among fully vaccinated participants (median: 13 days) versus those not fully vaccinated (median: 13 days; p=0.50), or in duration of culture positivity (medians: 5 days and 5 days; p=0.29). Among fully vaccinated participants, overall duration of culture positivity was shorter among Moderna vaccine recipients versus Pfizer (p=0.048) or Janssen (p=0.003) vaccine recipients.

Conclusions As this field continues to develop, clinicians and public health practitioners should consider vaccinated persons who become infected with SARS-CoV-2 to be no less infectious than unvaccinated persons. These findings are critically important, especially in congregate settings where viral transmission can lead to large outbreaks.”