Domestically Acquired Cases of Cyclosporiasis — United States, May–June 2019

Last Updated JUNE 27, 2019 4:00 PM EDT

While cyclosporiasis cases are reported year-round in the United States, cyclosporiasis acquired in the United States (i.e., “domestically acquired,” or cases of cyclosporiasis that are not associated with travel to a country that is considered endemic for Cyclospora) is most common during the spring and summer months. The exact timing and duration of U.S. cyclosporiasis seasons can vary, but reports tend to increase starting in May. In previous years the reported number of cases peaked between June and July, although activity can last as late as September. The overall health impact (e.g., number of infections or hospitalizations) and the number of identified clusters of cases (i.e., cases that can be linked to a common exposure) also vary from season to season.

Latest Information

  • The number of reported cases of domestically acquired cyclosporiasis has increased from the previous month and remains elevated in the United States since May 1, 2019.
  • As of June 24, 2019, 23 laboratory-confirmed cases of cyclosporiasis were reported to CDC by 10 states and New York City in people who became ill since May 1, 2019 and who had no history of international travel during the 14-day period before illness onset.
    • The median illness onset date was May 13, 2019 (range: May 3–June 10, 2019).
    • At least two people were hospitalized; no deaths were reported.
    • At this time, no specific vehicle of interest has been identified, and investigations to identify a potential source (or sources) of infection are ongoing. It is not currently known whether reported cases are related to each other or represent one or more outbreaks.
At a Glance
  • States reporting cases: 11
  • Deaths: 0
  • Hospitalizations: 2
Case Count Map

Geographic Distribution of Reported Cases of Domestically Acquired Cyclosporiasis with Illness Onset on or after May 1, 2019*

outbreak map

Click map to view case count map.

Progression of the Outbreak Investigation

While cyclosporiasis cases are reported year-round in the United States, cyclosporiasis acquired in the United States (i.e., “domestically acquired”, or cases of cyclosporiasis that are not associated with travel to a country that is considered endemic for Cyclospora) is most common during the spring and summer months. The exact timing and duration of U.S. cyclosporiasis seasons can vary, but reports tend to increase starting in May. In previous years the reported number of cases peaked between June and July, although activity can last as late as September. The overall health impact (e.g., number of infections or hospitalizations) and the number of identified clusters of cases (i.e., cases that can be linked to a common exposure) also vary from season to season.

Latest Information

  • As of May 29, 2019, 2 laboratory-confirmed cases of cyclosporiasis were reported to CDC by two states in people who became ill since May 1, 2019 and who had no history of international travel during the 14-day period before illness onset.
    • The median illness onset date was May 5, 2019 (range: May 4–May 6, 2019).
    • No hospitalizations or deaths have been reported.
    • At this time, no specific vehicle of interest has been identified, and investigations to identify a potential source (or sources) of infection are ongoing. It is not currently known whether reported cases are related to each other or represent one or more outbreaks.

 

Page last reviewed: June 27, 2019