A recent paper from Brigham and Women’s Hospital published in Clinical Infectious Disease documents presence of the S1 portion of the spike protein in blood soon after a jab with the mRNA vaccine, developing as early as one day.
Crucially, the S1 protein is not restricted to the shoulder receiving the injection or the draining lymph nodes, but is found in the blood stream. The protein peaks at 5 days to persist till 14 days. The clinical implications are unclear as per the researchers, but one must bear in mind reports from Israel and the US of more than expected myocarditis in young males soon after RNA vaccination.
The myocarditis albeit so far has been mild, but has necessitated administration of intravenous immunoglobulin and oral steroids.