Date of Award

January 2020

Document Type

Open Access Thesis

Degree Name

Master of Public Health (MPH)


School of Public Health

First Advisor

James Hadler

Second Advisor

Linda Niccolai


Introduction: Cyclosporiasis is a foodborne, parasitic infection, causing prolonged debilitating diarrhea, especially in immunosuppressed persons. Exposure to Cyclospora occurs mainly through ingestion of contaminated fresh produce, often during international travel. Nationally, it has been increasing in the United States. Connecticut surveillance data have yet to be systematically analyzed.

Methods: Active surveillance of cyclosporiasis in Connecticut has been conducted since 1997, including follow up of laboratory-confirmed cases by chart review and interview. Data collected include patient demographics, symptoms, severity of illness, and exposures. Data from 1997-2019 were analyzed to identify trends in incidence and changing demographics and sources of exposure.

Results: Overall, incidence of cyclosporiasis in Connecticut was relatively stable from 1997-2012, but significantly increased from 2013-2019 (p < 0.001) from <10 cases/year to 101 in 2019. Increases were seen among all demographic groups, except for children (<18 years). The proportions of cases identifying as Hispanic, most recently 13.4%, and of cases domestically acquired, most recently 79%, have been increasing (p < 0.01). Most internationally-acquired cases (89.6%) traveled to Latin America. Introduction of culture independent diagnostic testing (CIDT) in 2015 was associated with a doubling of cases, but the proportion diagnosed by CIDT has remained stable since.

Conclusions: Cyclosporiasis incidence in Connecticut is increasing, most now due to domestic acquisition. Use of CIDT contributed to an initial increase in cases in 2015, but not to the increase in cases since. Clinicians should increasingly test for Cyclospora in persons without international travel who present with prolonged watery diarrhea.


This is an Open Access Thesis.

Open Access

This Article is Open Access