The vaccine is known to cause Gilliam Barre syndrome/GBS (rare but it happens). It also is known to trigger other underlying conditions, including nerve disorders. This has been confirmed by my own doctor and my pharmacist. I had the first (of 2) doses a week ago and it triggered the worst case of sciatica ever. I am in so much pain, and I've been advised not to take the second dose (due in 2 months). I am also very afraid that this sciatica pain will radiate outward to the rest of my body which will then be diagnosed as GBS. I know 2 people who had the first shot and one now has sciatica, and the other is very sick. This is a terrible vaccine. It replaces a previous version that was very dangerous.