Well, first of all if they had used more geographical regions (I don't know what the official amazon buzzword), they shouldn't have real bad problems. I don't know about you, but I believe mission critical systems should be hosted in at least 2 physically different data centers. When it's life critical, this should be a no brainer.

Second of all, according to Amazon PR speak this failure should not be possible. Every person in IT worth their salt should know PR speak is not to be trusted. Being reliant on AWS for your average business app is completely okay though. However, hosting apps which might endanger peoples lives on black box technology over which you have little influence is moronic imo.

Last but not least I seriously question the privacy implications of this. Hosting parts of your medical app in the cloud is fine and I don't know the details of this app, but I wouldn't be happy to know that my medical history is stored by some third party I don't entirely trust with such sensitive data.