Vaccine boosters and post-vaccination superinfections both provide significant immunity and potentially break up the pandemic against COVID-19, according to new lab research from Oregon Health & Science University.
the study, Med“>Published Wednesday in the magazine withis the latest in a series of OHSU discoveries using blood samples to characterize the immune response to SARS-CoV-2.
“As the number of sub-omicron cases rises and as global vaccination and booster campaigns continue, an increasing proportion of the global population will acquire robust immune responses that may be protective against future variants of SARS-CoV-2,” the researchers concluded.
The research measured a robust immune response among samples from 99 OHSU employees who had blood drawn for the research. Notably, the researchers measured an equally robust immune response to the virus — with significant increases in size, potency and breadth — among people whose blood was drawn three months after a third booster dose of the vaccine and another group one month after infection.
Additionally, the study found that the immune response was equally robust among people 65 and older.
“Early in the pandemic, we had very high mortality in some vulnerable groups, such as seniors in nursing homes, but that reality is slowly changing,” said a senior co-author. Marcel Kerlin, MD, Assistant Professor of Medicine (Infectious Diseases) at OHSU School of Medicine and OHSU Medical Director for Occupational Health. “Our study supports the idea that vaccination is a pathway to milder disease. Even if you are older, your chances of getting seriously ill if you are reinfected appear to be much lower than they were at the start of the epidemic.”
Co-author Fikadu Tavisi, Ph.D.An assistant professor of molecular microbiology and immunology at the OHSU School of Medicine, said he expects a more robust immune response among people receiving the new booster bivalent vaccine that targets BA.4 and BA.5 variants.
“We expect that updated vaccine strategies with variant-specific regimens will significantly improve the range of the immune response and provide better protection against SARS-CoV-2 variants,” he said.
In contrast to the beginning of the epidemic, SARS-CoV-2 is no longer “new” to the human immune system. Most people in the world have now been vaccinated, infected, or both – which means the virus faces a more effective immune response with each new infection.
Kerlin said the new study likely reflects the fact that the virus is evolving to be more transmissible but less harmful.
“Evolutionary pressure is driving the virus to find more ways to infect people at the expense of disease, probably,” he said. Pathogenicity refers to the ability to cause symptoms associated with a disease.
Funding for this study was supported by the MJ Murdock Charitable Trust; OHSU Foundation; National Institutes of Health Training Scholarship T32HL083808; and a grant from the OHSU Fund Create IDEA. The content is the sole responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.