Transmission electron micrograph of SARS-CoV-2 virus particles isolated from a patient. Image acquisition and color enhancement at the NIAID Integrated Research Facility (IRF) in Fort Detrick, Maryland. Image Credit: NIAID

New research from UNC-Chapel Hill suggests that those who have previously had SARS-CoV-2 infection will develop a significant antibody response to the first dose of the mRNA-based COVID-19 vaccine. In fact, one dose of the vaccine could give those who had COVID-19 the same antibody protection as two doses of the vaccine could give those who did not have COVID-19.

This is welcome news for many who have recovered from the virus and are now wondering if they should get a vaccine if they are eligible. Previous CDC guidelines indicated that people with a history of SARS-CoV-2 infection may temporarily delay vaccination while supplies are limited.

“We observed that the antibody response to an mRNA vaccine dose in previously infected people was nearly twice that of people who had no evidence of previous infection,” said Allison Aiello, Ph.D., professor of epidemiology at UNC Gillings School of Global Public Health. “In addition, the response to the first vaccination in people with previous infection was similar to the response to two doses of vaccine in seronegative people. Our study is unique in that we were able to track the SARS-CoV-2 antibody responses lengthways for a few cases Months prior to vaccination and showed that the response to the first dose of vaccine in seropositive subjects was robust for a number of different patterns of antibody response over time. “

“These results support a new and growing body of research suggesting that previous SARS-CoV-2 infection could act as a primer for the immune response to the first dose of an mRNA-based SARS-CoV-2 vaccine,” said Emily Ciccone, MD, MHS, the study’s lead author, clinical instructor, and fellow in the Infectious Diseases Department at the UNC School of Medicine. “If future studies show that this immune response is permanent and protects against subsequent SARS-CoV-2 infection, people with a history of infection may be able to forego the second dose of an mRNA-based vaccine.”

These results, which are currently being preprinted on medRxiv, come from the UNC’s longitudinal study COVID Health Care Personnel (HCP), a joint initiative of the School of Medicine, the Gillings School and the UNC Institute for Global Health and Infectious Diseases. The study tracked a group of HCPs at UNC Health from July 2020 to investigate their risk factors for infection and their change in SARS-CoV-2 antibody levels over time.

HCPs in the study had the opportunity to receive the SARS-CoV-2 vaccine Moderna or Pfizer-BioNtech from mid-December 2020 through UNC Health’s vaccination program. The study team compared the antibody responses before and after vaccination between previously tested study participants positive for COVID-19 (seropositive) at any point in time and for those who had no antibodies against SARS-CoV-2 (seronegative) before vaccination.

To date, more than 27 million Americans have been infected with SARS-CoV-2. The preliminary results of this study give potential hope that some people may be able to forego a second vaccination, which could have a significant impact on vaccine distribution strategies – both in the US and around the world.

The Gillings School authors include corresponding author Aiello, PhD students Deanna Zhu and Evans Lodge, research specialist Rawan Ajeen, and assistant professor of biostatistics Bonnie Shook-Sa, DrPH. School of Medicine authors include Ciccone and Ross Boyce, MD, MSc, assistant professors in the Infectious Diseases Department. Additionally, the co-authoring team includes a group of 12 people from the Gillings School and the School of Medicine who contributed to the study.

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More information:
Emily J. Ciccone et al. SARS-CoV-2 seropositivity after infection and antibody response to mRNA-based vaccination, medRxiv (2021). DOI: 10.1101 / 02.09.2021.21251319 Provided by the University of North Carolina at the Chapel Hill School of Medicine

Quote: A single dose of vaccine can provide protection for those with COVID-19 (2021, March 3), accessed on March 3, 2021 from has been

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