Unintentional intravenous vaccination may cause thrombocytopenia

No.13350342 ViewReplyOriginalReport
https://www.biorxiv.org/content/10.1101/2021.06.29.450356v1.abstract?%3Fcollection

TL:DR
The rare heart inflammation caused by covid vaccines are because the nurse inadvertently injected intravenously instead of intramuscularly causing an autoimmune response and platelet clumping. Some countries aspirate the needle (see below) to check the tissue they are injecting into isn't vascular but most DON'T and the world health organisation don't recommend it.

https://ed-areyouprepared.com/wp-content/uploads/2018/12/Do-you-need-to-aspirate-when-giving-intramuscular.pdf