"A major change in the security architecture of Europe was been made without Russian consent, " Professor Michael Mandelbaum of Johns Hopkins University said.

CNN: AllPolitics - Big Issues Confront NATO At Madrid Summit

CNN's Adam Reiss, Ted Metzger, Raelyn Johnson, Joe Johns and Michael Martinez contributed to this report.

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"The advantage of using these social media tools and Google is they're much faster than the CDC, " said Michael Paul, a doctoral student working on the Johns Hopkins Twitter research.

CNN: Tracking the flu with technology and Twitter