As of 14.15 BST. today the 9th of September, AstraZeneca put the brakes on the phase III trials of their new COVID vaccine as part of Operation Warp Speed. There are some 30,000 people around the United States involved in these trials. AstraZeneca published a press release on their website, claiming to a... " [...] voluntary pause of vaccination across all trials to allow an independent committee to review the safety data of a single event of an unexplained illness that occurred in the UK Phase III trial." That unexplained illness was suspected highly to be Traverse Myelitis, and it is fairly serious and 'rare' condition of a inflamed spinal cord, it effects the autonomic nervous system and can lead to high blood pressure. It has been connected to a vaccine a decade ago.