This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated.

The monthlong outbreak of a virulent E. coli strain tied to romaine lettuce has now sent 42 people to hospitals in 19 states, federal health officials said Wednesday.

The U.S. Centers for Disease Control and Prevention added 31 people to its tally of victims in the outbreak. The agency has linked the outbreak to the Imperial Valley growing region centered around Yuma, Ariz., where more than 90% of the nation’s winter lettuce is cultivated.

Half the 84 cases have resulted in hospitalizations, including nine for treatment of kidney failure, according to the CDC.

No grower, packer or distributor has been implicated thus far, the agency said.

Read the full story on LATimes.com.