evidence: The spike protein found on the surface of Covid-19 virus cells causes changes to cells in the small blood vessels of the heart, according to early findings presented at the European Society of Cardiology Congress. [...] There is some previous evidence to suggest that following Covid-19 illness, the spike protein can remain in the bloodstream after the virus has gone and travel far from the site of infection. This research could help explain and ultimately treat some of the effects of severe Covid-19 infection, where levels of the virus are particularly high. [...] Being fully vaccinated against Covid-19 means that your immune system will rapidly produce antibodies against the spike protein if it encounters the virus. These antibodies will work to neutralise any circulating spike protein.