The U.S. Centers for Disease Control and Prevention headquarters are shown in Atlanta. A report by the CDC said Wednesday that the number of suspected cyclosporiasis cases has risen to more than 18,000. File photo by Erik S. Lesser/EPA-EFE/

July 29 (UPI) -- The number of suspected cyclosporiasis cases in the United States have risen to more than 18,000, with more than 6,700 lab-confirmed cases since May 1, the U.S. Centers for Disease Control and Prevention said Wednesday.

Cases of the gastrointestinal infection, which causes explosive diarrhea, have now been recorded in 45 states as part of this outbreak, the CDC said. The number of confirmed cases marks an increase of more than 2,500 since its last report July 21.

It is now considered the largest known outbreak of cyclosporiasis in U.S. history, The Hill reported. There have been 423 hospitalizations and no deaths, the CDC said.

Michigan has the most cases, with more than 10,000 reported in that state alone. It is followed by Ohio, which has more than 2,600 reported cases. Health officials in other states, including Kentucky, Illinois and Indiana, have also said that cases are on the rise.