| 14 April 2024, Sunday |

‘Significant increase’ in protection vs Omicron from mRNA boosters, study says

According to a Danish research released on Wednesday, getting a third dosage of either Pfizer-or BioNTech’s Moderna’s COVID-19 vaccine provides a “substantial boost” in protection against the Omicron variant in aged persons.

The study, which has not yet been peer-reviewed, looked at the efficacy of COVID-19 vaccines based on mRNA technology against the Delta variant and the new, more infectious Omicron form.

“Our analysis adds to accumulating data that initial vaccine protection against Omicron from BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) diminishes rapidly over time, with booster immunization providing a considerable increase in protection,” the scientists said in the report.

The study was conducted by researchers at Denmark’s top infectious disease authority, Statens Serum Institut (SSI). It analyzed data from three million Danes gathered between Nov. 20 and Dec. 12.

Among those who recently had their second vaccine dose, effectiveness against Omicron was measured at 55.2% for Pfizer-BioNTech and 36.7% for Moderna, compared to unvaccinated people.

But that protection quickly waned over the course of five months, the researchers said.

“We see that the protection is lower and decreases faster against Omicron than against the Delta variant after a primary vaccination course,” study author Palle Valentiner-Branth said.

However, a third dose of Pfizer-BioNTech’s vaccine restored protection to 54.6% in people aged 60 or more who had been inoculated 14 to 44 days earlier, compared to those with only two doses.

The study confirms the findings of a recent British study, which also showed a rapid decline in protection against Omicron over time and an increase following a booster with Pfizer-BioNTech’s vaccine.

“In light of the exponential rise in Omicron cases, these findings highlight the need for massive rollout of vaccinations and booster vaccinations,” the researchers said.

  • Reuters