title: Population-based active surveillance for Cyclospora infection--United States, Foodborne Diseases Active Surveillance Network (FoodNet), 1997-2009.
abstract: BACKGROUND
  Cyclosporiasis is an enteric disease caused by the parasite Cyclospora cayetanensis. Since the mid-1990 s, the Centers for Disease Control and Prevention has been notified of cases through various reporting and surveillance mechanisms.
  
  
  METHODS
  We summarized data regarding laboratory-confirmed cases of Cyclospora infection reported during 1997-2009 via the Foodborne Diseases Active Surveillance Network (FoodNet), which gradually expanded to include 10 sites (Connecticut, Georgia, Maryland, Minnesota, New Mexico, Oregon, Tennessee, and selected counties in California, Colorado, and New York) that represent approximately 15% of the US population. Since 2004, the number of sites has remained constant and data on the international travel history and outbreak status of cases have been collected.
  
  
  RESULTS
  A total of 370 cases were reported, 70.3% (260) of which were in residents of Connecticut (134 [36.2%]) and Georgia (126 [34.1%]), which on average during this 13-year period accounted for 29.0% of the total FoodNet population under surveillance. Positive stool specimens were collected in all months of the year, with a peak in June and July (208 cases [56.2%]). Approximately half (48.6%) of the 185 cases reported during 2004-2009 were associated with international travel, known outbreaks, or both.
  
  
  CONCLUSIONS
  The reported cases were concentrated in time (spring and summer) and place (2 of 10 sites). The extent to which the geographic concentration reflects higher rates of testing, more sensitive testing methods, or higher exposure/infection rates is unknown. Clinicians should include Cyclospora infection in the differential diagnosis of prolonged or relapsing diarrheal illness and explicitly request stool examinations for this parasite.
authors.affiliation: LifeSource Biomedical, LLC, Moffett Field, California, USA. rhall4@cdc.gov
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Hall
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Jones
authors.forename: Sharon
authors.initials: S
authors.lastname: Hurd
authors.forename: Glenda
authors.initials: G
authors.lastname: Smith
authors.forename: Barbara E
authors.initials: BE
authors.lastname: Mahon
authors.forename: Barbara L
authors.initials: BL
authors.lastname: Herwaldt
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002487:Centers for Disease Control and Prevention, U.S.; D002648:Child; D002675:Child, Preschool; D021744:Cyclospora / Q000254:growth & development / Q000302:isolation & purification*; D021866:Cyclosporiasis / Q000453:epidemiology* / Q000469:parasitology / Q000635:transmission; D003967:Diarrhea / Q000453:epidemiology* / Q000209:etiology; D004196:Disease Outbreaks; D005260:Female; D005517:Foodborne Diseases / Q000453:epidemiology* / Q000469:parasitology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D012621:Seasons; D014481:United States / Q000453:epidemiology; D055815:Young Adult