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Waning effectiveness of the third dose of the BNT162b2 mRNA COVID-19 vaccine
Tal Patalon1,2, Yaki Saciuk3, Asaf Peretz4,5
1Kahn Sagol Maccabi (KSM) Research & Innovation Center, Maccabi Healthcare Services, Tel Aviv, 68125, Israel. patalon_t@mac.org.il.
Abstract:
The duration of protection of the third (booster) dose of the BioNTech/Pfizer BNT162b2 mRNA Coronavirus Disease 2019 vaccine has been the subject of recent investigations, as global discussions around the necessity and effectiveness of a fourth dose are already underway. By conducting a retrospective study implementing a test-negative case-control design, analyzing 546,924 PCR tests performed throughout January 2022 by 389,265 persons who received at least two doses, we find that the effectiveness in each month-since-vaccination decreases significantly. Compared to those vaccinated five months prior to the outcome period, on August 2021, relative protection against infection waned from 53.4% a month after vaccination to 16.5% three months after vaccination. These results suggest that there is a significant waning of vaccine effectiveness against the Omicron variant of the third dose of the BNT162b2 vaccine within a few months after administration. Additional information could assist to comprehensively estimate the effectiveness of the three-dose-strategy.
Insights
Protection from the BioNTech/Pfizer COVID-19 vaccine booster wanes significantly within months. Effectiveness against the Omicron variant decreased notably, suggesting a need for further study on booster duration.
Area of Science:
- Immunology
- Vaccinology
- Epidemiology
Background:
- Booster doses of mRNA vaccines like BioNTech/Pfizer BNT162b2 are crucial for sustained COVID-19 protection.
- Ongoing global discussions address the need for fourth vaccine doses due to waning immunity.
Purpose of the Study:
- To investigate the duration of protection offered by the third (booster) dose of the BNT162b2 mRNA vaccine.
- To assess the waning effectiveness of the COVID-19 vaccine booster against the Omicron variant.
Main Methods:
- Retrospective study utilizing a test-negative case-control design.
- Analysis of 546,924 PCR tests from 389,265 individuals vaccinated with at least two doses.
- Data collected in January 2022.
Main Results:
- Vaccine effectiveness significantly decreased each month after vaccination.
- Protection waned from 53.4% one month post-vaccination to 16.5% three months post-vaccination against infection.
- Observed waning effectiveness specifically against the Omicron variant.
Conclusions:
- The third dose of the BNT162b2 vaccine shows significant waning effectiveness against the Omicron variant within months.
- Further research is needed to fully understand the long-term effectiveness of the three-dose COVID-19 vaccination strategy.
