Cyclospora cayetanensis Infection in Developed Countries: Potential Endemic Foci?

Abstract

Cyclospora cayetanensis infection has emerged as a significant public health concern worldwide. Developed countries are generally considered non-endemic for infection. However, sporadic cases and non-travel-related outbreaks of C. cayetanensis infections associated with domestically grown produce are becoming more common in developed countries. Cyclospora cayetanensis has been detected in fresh produce, surface water, wastewater, irrigation water, and soil in these countries, suggesting that the parasite may be more common in areas with advanced sanitation than previously thought and illustrating the potential risk for exposure and indigenous/autochthonous infections. The evidence suggests the possibility of foci of endemicity in developed countries, particularly in communities where sanitary conditions are compromised, and raises transmission issues that require further research to better define the risks for infection, how widespread C. cayetanensis may be in these areas, and to guide interventions against this infection. The main purpose of the present opinion was to evaluate the presence of cyclosporiasis in developed countries, which is a very important and ongoing issue in food safety.

Protozoan Infections Acquired from Food or Drinking Water: An Update

“…C. cayetanensis was detected in 0.3% samples of imported leafy greens, herbs, and berry samples in the USA and [208] in 0.28% of samples tested in Canada, of which spinach, cilantro, and blueberries were grown in the USA [208,215].…”

“…Outbreaks were linked to berries, cilantro, basil, and, more recently, ready-to-eat bagged salads imported or grown in the USA [207]. The first reported outbreak of cyclosporiasis in the USA was in Chicago and was possibly linked to a hospital water supply [208]. From 2018 to 2022 annual summertime outbreaks became regular in people who had no recent history of international travel and laboratory-confirmed cases of cyclosporiasis were linked to both imported and locally grown fresh produce [203,208].…”

“…The first reported outbreak of cyclosporiasis in the USA was in Chicago and was possibly linked to a hospital water supply [208]. From 2018 to 2022 annual summertime outbreaks became regular in people who had no recent history of international travel and laboratory-confirmed cases of cyclosporiasis were linked to both imported and locally grown fresh produce [203,208]. Outbreaks occurred between 1 May and 31 August 2021, with 1123 laboratory-confirmed cases in 36 states and 561 isolates were distinguished in 31 temporal genetic clusters (TGC) and 10 of these were associated with epidemiological clusters.…”

“…A foodborne outbreak in Stockholm, Sweden, was linked to sugar snap peas imported from Guatemala based on information obtained from laboratory-confirmed C. cayetanensis infected patients. In Europe, the sources of a foodborne outbreak in Germany were epidemiologically traced to lettuce and herbs from Germany, France, and Italy; the contamination of food crops probably derived from agricultural workers who had no access to sanitary facilities [208]. The long incubation period of up to two weeks and intermittent remissions confound case recognition and make it difficult to identify the infection source in the outbreaks [72].…”

Cyclospora cayetanensis: A Perspective (2020–2023) with Emphasis on Epidemiology and Detection Methods

“…There is a relationship between cyclosporiasis with poverty that carries implications for targeted public health interventions in resource-poor countries. Longitudinal and spatial analysis will be crucial to ascertain the impact of poverty on cyclosporiasis and the potential role of soil as a reservoir of infection to guide its prevention and control in endemic areas [ 122 ].…”