The number of Boston College students stricken with stomach symptoms grew to 80 on Tuesday, and all say they ate at a nearby Chipotle restaurant.
Although many of the students said they feared they'd been struck with the same E. coli bacteria that made 52 people in nine states sick this fall, Chipotle officials say they doubt it's E. coli this time.
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"Health officials in Boston believe this is likely a norovirus, which seems consistent with the pattern, in our estimation," Chipotle spokesman Chris Arnold told NBC News.