Safety and Immunogenicity of Pfizer-BioNTech COVID-19 Vaccine among Healthcare Workers in Lithuania

Strategic Insights -

A study conducted at the Lithuanian University of Health Sciences aimed to investigate the safety and immunogenicity of the Pfizer-BioNTech COVID-19 vaccine among healthcare workers 21 days after the first dose. Researchers analyzed data from 4,181 vaccine recipients and found that the first dose was associated with a 53.6% incidence of adverse events, mainly local reactions. Younger participants and women experienced adverse events more frequently. The study concluded that despite some moderate adverse events, no safety concerns or anaphylaxis were identified, and the vaccine induced an immune response in the majority of recipients.

Key Takeaways:

  • The study involved 4,181 healthcare workers in Lithuania who received the Pfizer-BioNTech COVID-19 vaccine and were analyzed 21 days after the first dose.
  • The first dose of the vaccine was associated with a 53.6% incidence of adverse events, mainly local reactions.
  • Adverse events occurred more frequently in younger participants and women, with 1.4% of participants experiencing moderate adverse events and 6.2% being incapacitated.
  • Seroconversion rates were lower in participants older than 47 years, with 94.5% of participants testing positive for IgG antibodies after the first vaccine dose.
  • The study concluded that the Pfizer-BioNTech vaccine induced an immune response in the overwhelming majority of recipients and identified no safety concerns or anaphylaxis.
  • The study emphasized the importance of future research into long-term adverse reactions and immune system programming.

Statistics:

  • 4,181 healthcare workers participated in the study.
  • 53.6% of participants experienced adverse events after the first dose of the vaccine.
  • 1.4% of participants experienced moderate adverse events.
  • 6.2% of participants were incapacitated after the first dose.
  • 94.5% of participants testing positive for IgG antibodies after the first vaccine dose.
  • Seroconversion rates were lower in participants older than 47 years.

Sources:

  • Adverse Events and Immunogenicity of mRNA-Based COVID-19 Vaccine among Healthcare Workers: A Single-Centre Experience. Medicina, 2022, 58(441): 441. (Medicina - http://www.mdpi.com/journal/medicina)
  • NewsRx. New COVID-19 Data Have Been Reported by Researchers at Lithuanian University of Health Sciences (Adverse Events and Immunogenicity of mRNA-Based COVID-19 Vaccine among Healthcare Workers: A Single-Centre Experience). Vaccine Weekly. April 13, 2022; p 414.