A new study has shown that older people who receive the third dose of either Pfizer-BioNTech’s COVID-19 vaccine or Moderna’s COVID-19 vaccine will have an increased chance of being protected against the Omicron variant.
Researchers in the study examined the effectiveness of COVID-19 vaccines that used mRNA technology against the Delta and Omicron variants of the virus.
In their study, the authors noted “our study adds to emerging evidence that the primary vaccine protection against Omicron, BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna), rapidly decreases over time and that booster vaccination provides increased protection.”
Researchers from Statens Serum Institut (SSI), Denmark’s top infectious disease authority, conducted the study. During the period of November 20 to December 12, the study collected data from three million Danes.
The effectiveness of Pfizer-BioNTech and Moderna against Omicron was measured at 55.2% for people who recently received their second vaccine dose and 36.7% for those who had not received the vaccination.
During the five-month period, the researchers noted that that protection soon waned.
In this study, study author Palle Valentiner-Branth observed that the protection against Omicron was lower and decreased faster than against the delta variant.
People 60 or older who had been inoculated 14 to 44 days earlier with Pfizer-BioNTech’s vaccine returned to 54.6% protection after receiving the third dose versus those who had only received two doses.
Pfizer-BioNTech’s vaccine increases protection following a booster dose. A recent British study also demonstrated a rapid decline in protection against Omicron over time and an increase following a booster with a booster dose of the vaccine.
Researchers said the findings underline the importance of massive vaccination campaigns and booster shots in light of the exponential rise in Omicron cases.