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Epi Curves
Multistate Outbreak of Listeriosis Linked to Whole Cantaloupes from Jensen Farms, Colorado (FINAL UPDATE)
This investigation is closed.Listeria monocytogenes infection (listeriosis) is an important cause of illness in the United States. More information about listeriosis, and steps people can take to reduce their risk of infection, can be found on the CDC Listeria website.
The outbreak can be visually described with a chart showing the number of persons who became ill each day. This chart is called an epidemic curve or epi curve.
Persons infected with an outbreak-associated subtype of Listeria monocytogenes, by date of illness onset (Figure A) and date of clinical specimen collection (Figure B), 2011 (147 cases reported to CDC as outbreak-associated)*
* Onset date not currently available for all persons with reported illness. Excludes a newborn diagnosed with listeriosis with a specimen date in November whose mother was reported as a case earlier in the outbreak.
Among persons for whom information was available, reported illness onset ranged from July 31, 2011 through October 27, 2011. Ages ranged from <1 to 96 years, with a median age of 78 years. Most ill persons were over 60 years old. Fifty-eight percent of ill persons were female. Among the 145 ill persons with available information on whether they were hospitalized, 143 (99%) were hospitalized.
Thirty-three outbreak-associated deaths were reported: Colorado (9), Indiana (1), Kansas (3), Louisiana (2), Maryland (1), Missouri (3), Montana (1), Nebraska (1), New Mexico (5), New York (2), Oklahoma (1), Texas (2), and Wyoming (2). Among persons who died, ages ranged 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.
Seven of the illnesses were related to a pregnancy; three were diagnosed in newborns and four were diagnosed in pregnant women. One miscarriage was reported.
Previous Epi Curves
Persons infected with the outbreak-associated strains of Listeria monocytogenes, by date of illness onset (Figure A) and date of clinical specimen collection (Figure B), 2011*
Onset date not currently available for all persons with reported illness
* n= 144 for whom complete information was reported to CDC by December 2, 2011. Excludes a newborn diagnosed with listeriosis with a specimen date in November whose mother was reported as a case earlier in the outbreak.
Among persons for whom information was available, reported illness onset ranged from July 31, 2011 through October 27, 2011. Ages ranged from <1 to 96 years, with a median age of 77 years. Most ill persons were over 60 years old. Fifty-eight percent of ill persons were female. Among the 144 ill persons with available information on whether they were hospitalized, 142 (99%) were hospitalized.
Thirty deaths were reported: Colorado (8), Indiana (1), Kansas (3), Louisiana (2), Maryland (1), Missouri (3), Nebraska (1), New Mexico (5), New York (2), Oklahoma (1), Texas (2), and Wyoming (1). Among persons who died, ages ranged from 48 to 96 years, with a median age of 82.5 years. In addition, one woman pregnant at the time of illness had a miscarriage.
Seven of the illnesses were related to a pregnancy; three were diagnosed in newborns and four were diagnosed in pregnant women. One miscarriage was reported.
Persons infected with the outbreak-associated strains of Listeria monocytogenes, by date of illness onset (Figure A) and date of clinical specimen collection (Figure B), 2011*
Onset date not currently available for all persons with reported illness
*n= 139 for whom information was reported to CDC by 9am EDT on November 1, 2011
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. Among the 134 ill persons with available information on whether they were hospitalized, 132 (99%) were hospitalized. State and local health departments in these and other states are investigating other listeriosis illnesses to determine if they are part of this outbreak.
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.
Five of the illnesses were related to a pregnancy; two were diagnosed in newborns and three were diagnosed in pregnant women. One miscarriage has been reported. Other outcomes are being monitored.
Persons infected with the outbreak-associated strains of Listeria monocytogenes, by date of illness onset (Figure A) and date of clinical specimen collection (Figure B), 2011*
Onset date not currently available for all persons with reported illness
* n= 133 for whom information was reported to CDC by 9am EDT on October 24, 2011
Among persons for whom information is available, illnesses began on or after July 31, 2011. Ages range from <1 to 96 years, with a median age of 77 years. Most ill persons are over 60 years old. Fifty-six percent of ill persons are female. Among the 130 ill persons with available information on whether they were hospitalized, 128 (98%) were hospitalized. State and local health departments in these and other states are investigating other listeriosis illnesses to determine if they are part of this outbreak. Twenty-eight deaths have been reported: Colorado (7), 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 84 years. In addition, one woman pregnant at the time of illness had a miscarriage. Four of the illnesses were related to a pregnancy; one was diagnosed in a newborn and three were diagnosed in pregnant women. One miscarriage has been reported. Other outcomes are being monitored.
Persons infected with the outbreak-associated strain of Listeria monocytogenes, by date of illness onset*
Onset date not currently available for all persons with reported illness
*n=123 for whom information on illness onset was reported to CDC by 9am EDT on October 17, 2011
Among persons for whom information is available, illnesses began on or after July 31, 2011. Ages range from <1 to 96 years, with a median age of 78 years. Most ill persons are over 60 years old. Fifty-eight percent of ill persons are female. Among the 120 ill persons with available information on whether they were hospitalized, 118 (98%) were hospitalized. Four of the illnesses were related to a pregnancy; one was diagnosed in a newborn and three were diagnosed in pregnant women. One miscarriage has been reported. Other outcomes are being monitored. Illnesses that occurred after September 23, 2011, might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported.
Persons infected with the outbreak-associated strain of Listeria monocytogenes, by date of illness onset*
*n= 99 for whom information on illness onset was reported to CDC by 11am EDT on October 3, 2011
Among persons for whom information is available, illnesses began on or after July 31, 2011. Ages range from 35 to 96 years, with a median age of 79 years. Most ill persons are over 60 years old. Forty-nine percent of ill persons are female. Among the 93 ill persons with available information on whether they were hospitalized, 91 (98%) were hospitalized. Two women were pregnant at the time of illness and the outcome of each pregnancy is being monitored. Illnesses that occurred after September 7, 2011, might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported.
Persons infected with the outbreak-associated strain of Listeria monocytogenes, by date of illness onset*
Onset date not currently available for all persons with reported illness
*n=108 for whom information on illness onset was reported to CDC by 9am EDT on October 6, 2011
Among persons for whom information is available, illnesses began on or after July 31, 2011. Ages range from 22 to 96 years, with a median age of 77 years. Most ill persons are over 60 years old. Fifty-five percent of ill persons are female. Among the 107 ill persons with available information on whether they were hospitalized, 105 (98%) were hospitalized. Three of the ill persons were pregnant women, and one miscarriage has been reported. The outcome of the other two pregnancies is being monitored. Illnesses that occurred after September 11, 2011, might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported.
Persons infected with the outbreak-associated strain of Listeria monocytogenes, by date of illness onset*
*n= 99 for whom information on illness onset was reported to CDC by 11am EDT on October 3, 2011
Among persons for whom information is available, illnesses began on or after July 31, 2011. Ages range from 35 to 96 years, with a median age of 79 years. Most ill persons are over 60 years old. Forty-nine percent of ill persons are female. Among the 93 ill persons with available information on whether they were hospitalized, 91 (98%) were hospitalized. Two women were pregnant at the time of illness and the outcome of each pregnancy is being monitored. Illnesses that occurred after September 7, 2011, might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported.
Persons infected with the outbreak-associated strain of Listeria monocytogenes, by date of illness onset*
Onset data not currently available for all persons with reported illness.
*n=83 for whom information on illness onset was reported to CDC by 11am EDT on September 29, 2011
Among persons for whom information is available, illnesses began on or after July 31, 2011. Ages range from 35 to 96 years, with a median age of 78 years old. Most ill persons are over 60 years old. Fifty-five percent of ill persons are female. Among the 79 ill persons with available information on whether they were hospitalized, 78 (99%) were hospitalized. Two women were pregnant at the time of illness and the outcome of each pregnancy is being monitored. Illnesses that occurred after September 3, 2011, might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported.
Persons infected with the outbreak-associated strain of Listeria monocytogenes, by date of illness onset*
Onset data not currently available for all persons with reported illness.
*n=55 for whom information on illness onset was reported as of 5pm EDT on September 20, 2011
Among persons for whom information is available, illnesses began on or after August 4, 2011. Ages range from 35 to 96 years, with a median age of 78 years old. Most ill persons are over 60 years old or have health conditions that weaken the immune system. Fifty-nine percent of ill persons are female. Among the 43 ill persons with available information on whether they were hospitalized, all were hospitalized. Eight deaths have been reported, 2 in Colorado, 1 in Maryland, 4 in New Mexico, and 1 in Oklahoma. Illnesses that occurred after August 28, 2011, might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported.
Persons infected with the outbreak-associated strain of Listeria monocytogenes, by date of illness onset*
Onset data not currently available for all persons with reported illness.
*n=31 for whom information on illness onset was reported as of September 19, 2011
Among persons for whom information is available, illnesses began on or after August 4, 2011. Ages range from 35 to 96 years, with a median age of 81 years old. Most ill persons are over 60 years old or have health conditions that weaken the immune system. Sixty-five percent of ill persons are female. Among the 28 ill persons with available information on whether they were hospitalized, all were hospitalized. Four deaths have been reported, one in Colorado, one in Oklahoma, and two in New Mexico. Illnesses that occurred after August 28, 2011, might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported.
Persons infected with the outbreak-associated strain of Listeria monocytogenes, by date of illness onset*
Onset data not currently available for all persons with reported illness.
*n=21 for whom information on illness onset was reported as of 9/14/2011
Among persons for whom information is available, illnesses began on or after August 15, 2011. Ages range from 38 to 96 years, with a median age of 81 years old. Most ill persons are over 60 years old or have health conditions that weaken the immune system. Sixty-two percent of ill persons are female. Among the 20 ill persons with available information on whether they were hospitalized, all were hospitalized. Two deaths have been reported, one in Colorado and one in New Mexico. Illnesses that occurred after August 25, 2011, might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported.
Persons infected with the outbreak-associated strain of Listeria monocytogenes, by date of illness onset*
Onset data not currently available for all persons with reported illness.
*n=16 for whom information on illness onset was reported as of 9/13/2011
Among persons for whom information is available, illnesses began on or after August 15, 2011. Ages range from 38 to 96 years, with a median age of 83 years old. Most ill persons are over 60 years old or have health conditions that weaken the immune system. Sixty-nine percent of ill persons are female. Among the 15 with information available, all were hospitalized. One death has been reported. Illnesses that occurred after August 28, 2011, might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported.
Persons infected with the outbreak-associated strain of Listeria monocytogenes, by date of illness onset*
Onset data not currently available for all persons with reported illness.
*n=15 for whom information on illness onset was reported as of 9/12/2011
Among persons for whom information is available, illnesses began on or after August 15, 2011. Ages range from 38 to 96 years, with a median age of 84 years old. Most ill persons are over 60 years old or have health conditions that weaken the immune system. Seventy-three percent of ill persons are female. All 15 (100%) patients were hospitalized, and one death has been reported. Illnesses that occurred after August 26, 2011, might not be reported yet due to the time it takes between when a person becomes ill and when the illness is reported.
