Major insurers felt the impact of Coventry Health Care Inc.'s announcement it would reduce its projected earnings because of unforeseen costs and more claims under Medicare Advantage, Bloomberg reports.

Aetna Inc., WellPoint Inc. and other insurers saw shares fall after the announcement.

"In this case, if Coventry has pneumonia, everyone else has at least a cold," said Sheryl Skolnick, an analyst with CRT Capital Group in Stamford, Connecticut, in a telephone interview with Bloomberg. "Now you have to start thinking about what are the implications for bad news in 2009. The 2009 estimates haven't come down as hard or as fast as the 2008 estimates, and they have to start coming down right away."

To read the full story by Bloomberg, click here.