A deadly food-borne bacteria linked to cantaloupes in more than a dozen states is suspected of killing one person in Maryland and sickening another in Virginia, health officials confirmed on Thursday.

Officials in Maryland and Virginia declined to identify the two people affected, but they said that each tested positive for a strain of listeria associated with the national outbreak that has killed eight people and sickened 55 in 14 states since early August. Most of the victims were older than 60, the Centers for Disease Control and Prevention said.

Earlier this week, the Food and Drug Administration determined that the listeria-infected cantaloupes were produced at Jensen Farms, a Colorado operation that has voluntarily recalled the 300,000 cases of cantaloupes it shipped from July 29 through Sept. 10.

Cantaloupes from other farms in Colorado, or elsewhere in the country, have not been linked to this outbreak, and none of the fruit at issue was shipped directly to the Washington area. But wholesalers who did business with Jensen Farms could have sold the cantaloupes to retailers in this region.

The Maryland victim lived in the central part of the state, according to David Blythe, state epidemiologist at the Maryland Department of Health and Mental Hygiene. But investigators have yet to determine where and when the cantaloupe was purchased. “Exactly how this case patient got ill is as yet unknown and may never be determined,” Blythe said in an e-mail through a spokeswoman.

In Virginia, the person who fell ill is an elderly Northern Virginia resident who was exposed to tainted cantaloupes while visiting Colorado, said Jun Yang, senior epidemiologist at the Virginia Department of Health. That person had underlying conditions that made her more vulnerable to the listeria bug, Yang said.

Listeria is an uncommon bacteria rarely found in produce. Infections from this bug are rare, but the elderly and people with weakened immune systems are vulnerable to them. Pregnant women who are infected could suffer devastating consequences, as listeria can result in still births or birth defects.

The number of deaths and infections tied to the listeria outbreak has jumped in recent days. The numbers will most likely climb, because listeria has a long incubation period, said Erik Olson, a director at the Pew Health Group. Illness can manifest itself up to two months after the bacteria is consumed. “There’s a long wait-and-see period,” he said.

The FDA added Thursday: “Because a shelf life of a cantaloupe can last about two weeks, it is also possible that some of the recalled product could still be in commerce or in home refrigerators.”