Also for anyone having difficulty it's really not that hard to just get 6000. Just keep your velocity as high as possible but under red. I leave my resistance at 0% and then tilt back up when i'm about to hit the water. That way you get to about 5500 at 150 mph and then reduce speed until you get to 6000
vaccines aren't 100% effective and development does adjust when you evolve the disease. I just had a round where they developed the vaccine and it said that it didn't work so they had to use another 500 days to make a new one