Epi Curve

Vibrio parahaemolyticus illnesses associated with consumption of shellfish, United States, 2013

Posted October 21, 2013 11:45 AM ET

Cases can be visually described with a chart showing the number of persons with illnesses beginning each week. This chart is called an epi curve.

Persons infected with the outbreak strain of Vibrio parahaemolyticus, by date of illness onset

Date of specimen collection was used if Illness onset date was not known

Because of the time needed for diagnosis and reporting, these 103 cases were reported to PulseNet from May 31 through September 30, 2013; during the same timeframe in 2012 and 2011, 52 isolates and 6 isolates, respectively, were reported with this DNA “fingerprint.”  The DNA “fingerprint” associated with this cluster has accounted for an increasing percentage of all Vibrio parahaemolyticus “fingerprints” in the PulseNet database in recent years.  To date in 2013, it accounts for 50%, compared with 30% in 2012, and 10% in 2011

Among persons for whom information is available, ill persons range in age from 22 years to 85 years, with a median of 51 years, and 62% of ill persons are male. Six ill persons have reported being hospitalized. No deaths have been reported.