Sky News. 11 June 2021: Airlines are now advising people who have been vaccinated NOT to fly. Yep, you heard me correctly. Airlines in Spain and Russia are warning people who’ve been vaccinated against Coronavirus NOT to travel because of the risk of BLOOD CLOTS. Now, this is a well known risk of long-haul flights. But, it apparently is exacerbated by the potential side effects — the clotting side effects — of the Covid-19 vaccines.