Abstract
Introduction: Many countries are administering a third dose of COVID-19 vaccines, but the evaluation of vaccine-induced immunity is insufficient. In addition, there are few reports of long-term observation of anti-spike IgG antibody titers after the vaccination in the Japanese population. This study aimed to evaluate anti-spike IgG levels in the Japanese health care workers six months after the BNT162b2 vaccination.
Methods: Dynamics of anti-spike IgG levels were assessed over a six-month period following the second vaccination in 49 participants (Analysis-1). A cross-sectional assessment of anti-spike IgG levels six months after the second vaccination was performed in 373 participants (Analysis-2).
Results: In Analysis-1, the geometric mean titer of anti-spike IgG was lower in the older age group and decreased consistently after the second vaccination regardless of age. In Analysis-2, the anti-spike IgG level was significantly negatively associated with age (r = -0.35, p < 0.01). This correlation remained statistically significant (r = -0.28, p < 0.01) after adjustment for sex, BMI, smoking habits, alcohol drinking habits, allergies, and fever or other adverse reactions at the time of vaccination. Additionally, participants who drank alcohol daily had significantly lower anti-spike IgG levels than participants who had never drunk alcohol. Sex, smoking habits, allergy, and fever and other side effects after vaccination did not show a significant association with anti-spike IgG levels.
Conclusions: Six months post-vaccination, the anti-spike IgG level was substantially lower in older persons and daily alcohol drinkers. This may be an indication for an additional vaccine dose for these at-risk categories.
Keywords: Anti-spike IgG antibody; BNT162b2; COVID-19.
【저자키워드】 COVID-19, BNT162b2, Anti-spike IgG antibody, 【초록키워드】 COVID-19, IgG, vaccination, cross-sectional, Dynamics, Sex, smoking, alcohol, vaccine dose, COVID-19 vaccines, anti-Spike IgG, Fever, Older age, Antibody titer, Health care worker, allergy, age, Japanese, BMI, correlation, association, dose, Adverse reaction, Vaccine-induced immunity, observation, Older, Side effect, second vaccination, categories, allergies, participant, geometric mean titer, significantly lower, country, anti-spike IgG levels, evaluate, significantly, addition, remained, was performed, statistically significant, anti-spike IgG level, were assessed, 【제목키워드】 Dynamics, IgG antibody, COVID-19 vaccination, Health care worker,