An outbreak of listeria has killed at least 13 people and infected 72 across 18 states, the U.S. Centers for Disease Control and Prevention said.

The figures may place the outbreak - traced to cantaloupe at Jensen Farms’ production fields in Granada, Colorado – as possibly the worst the worst food-borne outbreak in the U.S. in the past decade, according to the Associated Press.

The death toll was 2 in Colorado, 1 in Kansas, 1 in Maryland, 1 in Missouri, 1 in Nebraska, 4 in New Mexico, 1 in Oklahoma, and 2 in Texas.

New Mexico, Kansas and Wyoming are investigating further deaths linked to the disease - bringing a possible total of 16, 12 more than last week, AP reported.

The CDC said two weeks ago that Jensen Farms issued a voluntary recall of its Rocky Ford-brand cantaloupes after being linked to the outbreak.

Listeria is caused by eating food contaminated with the bacterium Listeria monocytogenes. It usually affects older adults, pregnant women, newborns and adults with weakened immune systems, according to the CDC.

Symptoms can include fever, muscle aches, diarrhea and other stomach problems. Pregnant women may only experience a mild-flu-like illness, however the infection could lead to miscarriage, stillbirth, premature delivery, or life-threatening infection of the newborn.