"We're having a lot of companies report really great quarters and no one cares," Cramer said. "And I think that has a lot to do with Ebola, and less to do with the fact that interest rates went below 2 [percent]."
The "Squawk on the Street" anchor said he watched Wednesday's U.S. market futures take a sharp negative turn as soon as the first reports came out that a second Texas nurse tested positive for the virus.
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And while the U.S. government and the Centers for Disease Control and Prevention assure the public they can keep the virus under control, Cramer said some traders' fears are not entirely irrational.
"I think that when the government creates some confidence it's not rational," he said. "I think the government has created a lack of confidence in its response."
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