From Our 2013 Archives

CDC: Investigation of an Outbreak of Cyclosporiasis in the United States

On June 28, 2013, CDC was notified of 2 laboratory-confirmed cases of Cyclospora infection in Iowa residents who had become ill in June and did not have a history of international travel during the 14 days before the onset of illness. Since that date, CDC has been collaborating with public health officials in multiple states and the US Food and Drug Administration (FDA) to investigate an outbreak of cyclosporiasis. Preliminary details of the ongoing investigation are highlighted below.

Epidemiologic Investigation

  • As of July 24, 2013 (5pm EDT), CDC has been notified of 285 cases of Cyclospora infection in residents of multiple states, including Iowa, Nebraska, Texas, Wisconsin, Georgia, Connecticut, New Jersey, Minnesota, and Ohio. Illinois and Kansas have also notified CDC of one case each that may have been acquired out of state but in the United States.
  • Most of the illness onset dates have ranged from mid-June through early July.
  • At least 18 persons reportedly have been hospitalized in three states.
  • No food items have been implicated to date, but public health authorities are pursuing all leads. Previous outbreak investigations have implicated various types of fresh produce.
  • It is not yet clear whether the cases from all of the states are part of the same outbreak.
  • No common events (e.g., social gatherings) have been identified among the case patients.
  • Additional cases are currently under investigation and will be included on this page as states confirm them.

Laboratory Investigation

  • To date, CDC has confirmed 5 cases of Cyclospora infection in CDC laboratories. One of those cases was confirmed via telediagnosis.
  • CDC encourages laboratories to obtain confirmation of cases using telediagnosis. Telediagnosis allows for rapid laboratory confirmation. State health laboratories may submit images showing suspected Cyclospora oocysts to CDC. Images may be captured from modified acid-fast stained smears or from wet mounts examined by UV fluorescence microscopy. Both techniques require concentrated stool specimens. Instructions for submitting images for telediagnosis are found on the DPDx site.

SOURCE: CDC, July 25, 2013