Origin and spread 2011 United States listeriosis outbreak

listeria monocytogenes, bacterium responsible listeriosis

listeriosis infection caused bacterium listeria monocytogenes. outbreak determined originate jensen farms in holly, colorado after listeria monocytogenes found in cantaloupe samples @ jensen farms store in denver, colorado , @ farm s packaging plant. batch of cantaloupes had been shipped out on period july 29 through september 10 twenty-five states, including arkansas, arizona, california, colorado, idaho, illinois, kansas, minnesota, missouri, montana, nebraska, new jersey, new mexico, new york, north dakota, ohio, oklahoma, pennsylvania, south dakota, tennessee, texas, utah, virginia, , wyoming.

the outbreak first reported centers disease control on september 12, stated fifteen people in 4 states had been infected . on september 21, new report released cdc, bringing number of deaths 13 , number of confirmed cases 72. report stated further deaths being investigated determine if had been caused listeria infection. cdc report stated that, listeria sickens elderly, pregnant women , others compromised immune systems , median age of people had been infected 78. on september 30, update released cdc, reporting of 11 am (edt) sep 29, 2011 number of confirmed cases 84, number of deaths 15 , number of states involved 19. on october 4, cdc updated report 100 infected individuals in 20 states , total of 18 deaths outbreak. outbreak shown have continued spread new states, cdc update on october 7 stating number of cases had risen 109 in 23 states , 3 more people had died bring death toll 21. cdc update on october 12 put number of cases @ 116 23 deaths. update on october 18 increased number of cases 123 , number of deaths 25. october 25 update raised number of cases 133, 3 more people dying raise total 28. final update on december 8 confirmed 146 cases , 30 deaths. fatalities occurred in colorado (8), indiana (1), kansas (3), louisiana (2), maryland (1), missouri (3), nebraska (1), new mexico (5), new york (2), oklahoma (1), texas (2), , wyoming (1). among persons died, ages ranged 48 96 years, median age of 82.5 years. in addition, 1 woman pregnant @ time of illness had miscarriage.

listeria infections can cause pregnant women miscarry; first miscarriage attributed 2011 outbreak reported in october, in woman living in iowa. pregnant women advised avoid foods, such unpasteurized cheese , hot dogs, known have potential carry listeria, fruits such cantaloupe had not been identified sources of concern.

no list of retailers selling infected cantaloupes released either government or jensen farms. although last shipment september 10 , fruit had two-week shelf life, of september 29, number of illnesses , deaths expected continue rising, because incubation period exceed 1 month.

recalls retailers had sold jensen farms cantaloupes included kroger (september 15), safeway (september 15), aldi (september 16), , foods (september 16).

fda investigation

an investigation food , drug administration (fda) found contaminated cantaloupe harvest contained 4 separate listeria monocytogenes strains, governmental agency found unusual , still trying determine reason. on october 20, reported fda officials had found listeria on dirty, corroded equipment used jensen farms, had been bought used , utilized potato farming. stated government equipment s past use may have played role in contamination . water contaminated listeria found on floor of packing plant , determined workers moving around plant had spread it, contaminated water found on cantaloupe conveyor belt. noted officials jensen farms had passed food safety audit outside contractor 6 days before outbreak.

the method of how listeria bacteria first came in plant remains unknown, soil on farm determined clear of bacteria. suspected, however, dump truck used take culled melons cattle farm...could have brought bacteria facility . furthermore, bacteria growth may have been caused condensation stemming lack of pre-cooling step remove field heat cantaloupe before cold storage.

house energy , commerce committee investigation

on october 21, house energy , commerce committee, committee panel of united states house of representatives, began own investigation outbreak. committee requested staff briefing jensen farms , of documents had on incident. requested information fda, cdc, , other governmental groups.