September 27, 2022 A new JAMA study of more than 10 million North Carolinians highlights just how effective COVID-19 vaccines, boosters and prior infection can be, both in reducing the risk of future infection and in preventing hospitalization and death.
sph.unc.edu
This article from UNC was published in late September, and the study results were published in JAMA. It's encouraging to read about how effective the original vaccine and the boosters have been over the past couple of years.
A new study of more than 10 million North Carolinians,
published this week in the Journal of the American Medical Association (JAMA), highlights just how effective COVID-19 vaccines, boosters and prior infection can be, both in reducing the risk of future infection and in preventing hospitalization and death.
The study gives a clearer picture of the separate protections that vaccination and prior infection might bring, and it compares the effectiveness of vaccines and boosters between those who have and have not had a previous case of COVID-19.
In addition, it demonstrates the effectiveness of the primary series of COVID-19 vaccines a year and a half after administration. The findings also suggest that omicron infection can protect against re-infection with omicron, although the level of protection wanes over time.
“Our study provides the most comprehensive characterizations of the effectiveness of primary and booster vaccination and prior infection in the United States,” said
Danyu Lin, PhD, who is the study’s lead researcher and the Dennis Gillings Distinguished Professor of Biostatistics at the UNC Gillings School of Global Public Health.
Researchers found that those who received the primary series of vaccines were less likely to become infected or experience severe outcomes from infection than those who were unvaccinated, even after a year and a half. Those who received a booster dose had higher protection than those who received only the primary series.
Results also show that boosting those who were previously uninfected conferred great protection, especially against hospitalization and death, while boosting also provided additional protection for previously infected individuals.
The data, captured between March 2020 and June 2022, comprises several SARS-CoV-2 variants, including omicron and its more recent subvariants. While the effectiveness of both vaccines and prior infection waned over time, especially against infection with the omicron variant,
the protection against hospitalization and death remained strong.
Lin says that the rapid decline of protection from boosters and prior infection against subsequent infection during the omicron period points to the need for bivalent (omicron) boosters.
He expects that the new boosters, which are now available to those ages 12 and up, will fare similarly to the booster for the original strain.
(more at link)
