The latest on the vaccine

Stat News reports that the patient that caused the one-week delay in the Astrazeneca vaccine trial had a serious neurological symptom but he's improving and could be discharge from hospital today.

The general thinking today is that one adverse event is very likely a coincidence in a trial that aims to enroll 30,000 participants -- someone is bounce to get sick.

On the negative side, it highlights how vaccines could take longer than hoped to finish trials. It also raises the risks for this particular vaccine, which is one of the more promising. A second or third outcome like this could take it out of the running.