The CDC just pulled the biggest lever in its emergency toolkit. On Friday, the agency raised its Ebola response to Level 1 — the highest internal alert — as the outbreak ravaging the Democratic Republic of Congo and Uganda shows no signs of slowing. More than 1,100 people have tested positive since May, and at least 250 have died, though officials concede the real number is likely far higher since the virus spread undetected for months. "We are very concerned about the...