The death toll caused by Listeria has risen to 16 in the U.S., reports CBS News.

According to Center of Disease Control and Prevention, the Colorado cantaloupe caused 13 deaths and 72 illnesses but the state and local health officials reported three additional deaths suspecting Listeria as the cause, making this food outbreak as the deadliest in more than a decade.

The death toll report released by the CDC confirmed four deaths in Mexico, two in Texas, one death each in Kansas, Nebraska, Colorado, Oklahoma, Missouri and Maryland.

However, the number of deaths is likely to increase. As the incubation period is long for the bacteria, finding the actual number of affected people is tough, says Dr. Robert Tauxe of the CDC.

Listeria - The Deadly Bacteria

According to CDC, Listeriosis, a serious infection usually caused by eating food contaminated with the bacterium Listeria monocytogenes, is an important public health problem in the United States. The disease primarily affects older adults, pregnant women, newborns, and adults with weakened immune systems. However, rarely, persons without these risk factors can also be affected.

Investigators have traced the outbreak to cantaloupes grown at Jensen Farms in Granada, Co., following the finding of listeria monocytogenes in a sample from there. The Food and Drug Administration has advised consumers to scrap the recalled cantaloupe.

There are about 800 reported cases a year in the United States, most of them linked to meat and soft cheese. Although other pathogens such as salmonella and E.coli create more number of illnesses but Listeria is the deadliest one, believe scientists.