The Centers for Disease Control and Prevention (CDC) Wednesday said the outbreak linked to Listeria-tainted cantaloupe has killed 23 of the 116 people sickened, and that four of the illnesses are related to pregnancies.

Pregnant women infected with Listeria typically experience only flu-like symptoms but the bacteria can be life-threatening to fetuses or newborn children. The CDC said that one outbreak-related illness had been diagnosed in a newborn, and three were diagnosed in pregnant women. One pregnant woman with listeriosis had a miscarriage.

In its latest update, current as of Oct. 11, the CDC added 7 more confirmed cases and two deaths, both from Louisiana, to the outbreak toll. Illnesses associated with eating contaminated cantaloupe from the single, implicated grower — Jensen Farms of Colorado — have now been reported by 25 states.

The confirmed cases so far since July 31:

Alabama: 1 illness

Arkansas: 1 illness

California: 1 illness

Colorado: 34 illnesses, 5 deaths

Idaho: 1 illness

Illinois: 1 illness

Indiana: 3 illnesses, 1 death

Iowa: 1 illness

Kansas: 7 illnesses, 2 deaths

Louisiana: 2 illnesses, 2 deaths

Maryland: 1 illness, 1 death

Missouri: 4 illnesses, 1 death

Montana: 1 illness

Nebraska: 6 illnesses, 1 death

New Mexico: 13 illnesses, 5 deaths

New York: 1 illness, 1 death

North Dakota: 1 illness

Oklahoma: 11 illnesses, 1 death

Oregon: 1 illness

South Dakota: 1 illness

Texas: 17 illnesses, 2 deaths

Virginia: 1 illness

West Virginia: 1 illness

Wisconsin: 2 illnesses

Wyoming: 3 illnesses, 1 death

Lab-confirmed cases of Listeria infection remain relatively rare in the U.S. – about 800 cases are reported each year – but Listeria monoctyogenes is a particularly virulent species of bacteria that can be fatal. The high cost of this outbreak, in terms of the ordeal for those stricken, is evident by the 20 percent death rate as well as the overwhelming need for medical treatment. 

Of 111 patients with available information, 109 have had symptoms so severe they had to be admitted to the hospital, the CDC said.

The CDC update did not include any new information about how the Colorado-grown cantaloupes were exposed to Listeria, which is more typically a factor in outbreaks involving deli meats, hot dogs or soft cheeses made with unpasteurized milk.  However, produce has been identified before as a source of Listeria infection and contaminated sprouts, celery and cabbage have caused previous outbreaks.

Investigators have said that in this case, outbreak strains of Listeria were found on equipment at Jensen Farms, but they have not said whether the cantaloupes contaminated the equipment or whether the equipment contaminated the melons.

CDC Outbreak Map: