How deadly is this cantaloupe Listeria monocytogenes outbreak and when will it end?

As of November 1, 2011, the CDC has reported that a total of 139 persons infected with any of the four outbreak-associated strains of Listeria monocytogenes have been reported to CDC from 28 states. 

The number of infected persons identified in each state is as follows:

Alabama (1), Arkansas (1), California (2), Colorado (39), Idaho (2), Illinois (3), Indiana (3), Iowa (1), Kansas (10), Louisiana (2), Maryland (1), Missouri (6), Montana (1), Nebraska (6), Nevada (1), New Mexico (15), New York (2), North Dakota (2), Oklahoma (11), Oregon (1), Pennsylvania (1), South Dakota (1), Texas (18), Utah (1), Virginia (1), West Virginia (1), Wisconsin (2), and Wyoming (4). 

 2011-11-05 at 1.17.56 PM.png

Among persons for whom information is available, reported illness onset ranges from July 31, 2011 through October 21, 2011. Ages range from <1 to 96 years, with a median age of 77 years. Most ill persons are over 60 years old. Fifty-seven percent of ill persons are female.

Twenty-nine deaths have been reported:

Colorado (8), Indiana (1), Kansas (3), Louisiana (2), Maryland (1), Missouri (2), Nebraska (1), New Mexico (5), New York (2), Oklahoma (1), Texas (2), and Wyoming (1).

Among persons who died, ages range from 48 to 96 years, with a median age of 81 years. In addition, one woman pregnant at the time of illness had a miscarriage.

 2011-11-05 at 2.33.26 PM.pngElaine Scallan, and others, reported earlier this year in “Foodborne Illness Acquired 
in the United States—Major Pathogens,” that if a Listeria monocytogenes illness (Listeriosis) is diagnosed, it will likely be reported to health officials (See, Table 2 – multiplier for underreporting is 1.0 and for underdiagnosis 2.1).  Therefore, there may be as many as 292 ill and 61 dead.

Jensen Farms recalled its whole cantaloupes (300,000 cases – six cantaloupes per case) on September 14 in response to the multi-state outbreak of Listeriosis.  According to the FDA, the recalled cantaloupes were produced from the end of July to September 10, 2011.

If you assume that all Listeria monocytogenes-tainted cantaloupe were off store shelves and were not consumed by customers after September 14, 2011 (given past recalls and outbreaks, not a great assumption), illnesses may well still occur through November 23, 2011 given that Listeria monocytogenes has an incubation period (ingestion to onset) from three to 70 days.

Deadly Fruit – far deadlier and not over yet.