Listeria, the gastrointestinal bacteria that is of particular danger to pregnant women, has been documented in Colorado, Texas, and Nebraska, leading health officials to declare an "outbreak" and warn at-risk individuals to take precautions.  Two patients in Colorado died from the infection.

The outbreak, according to the Colorado Department of Public Health and Environment, can be traced to tainted cantaloupe melons.  Though the bacteria is most often spread through unpasteurized soft cheeses, refrigerated smoked seafood, and deli meats, officials urge pregnant women, people over 60, and those with compromised immune systems to avoid eating cantaloupe as well as those other foods until the source of the contamination can be determined.  Officials note that deli meat can be safely consumed by pregnant women if it is reheated to 165 degrees Fahrenheit.

Pregnant women who contract listeria are at risk for convulsions, miscarriage, or stillbirth.