Table 5.

Changes of serum levels of selenium and zinc in the study groups among participants in the COVID-19 vaccine and influenza vaccine cohorts.

Study Cohort	Selenium, µg/dL Mean (95% CI)	Zinc, µg/dL Mean (95% CI)
COVID-19 vaccine
ABB C1® supplement
Baseline (n = 18)	15.98 (13.99–17.98)	102.33 (91.79–112.88)
Day 35 (n = 18)	17.57 (15.57–19.57)	119.28 (108.71–129.85)
Placebo
Baseline (n = 15)	17.45 (15.26–19.64)	106.20 (94.63–117.77)
Day 35 (n = 14)	14.90 (12.67–17.13)	102.64 (90.66–114.63)
Influenza vaccine
ABB C1® supplement
Baseline (n = 15)	12.33 (11.15–13.51)	91.40 (79.07–103–73)
Day 30 (n = 14)	16.94 (15.74–18.14)	116.75 (104.04–139.47)
Placebo
Baseline (n = 19)	13.07 (12.02–14.12)	91.32 (80.35–102.28)
Day 30 (n = 18)	13.41 (12.35–14.47)	102.23 (91.01–113.45)

CI: confidence interval.