2013 multistate outbreaks ofCyclospora cayetanensisinfections associated with fresh produce: focus on the Texas investigations

Abstract

SUMMARYThe 2013 multistate outbreaks contributed to the largest annual number of reported US cases of cyclosporiasis since 1997. In this paper we focus on investigations in Texas. We defined an outbreak-associated case as laboratory-confirmed cyclosporiasis in a person with illness onset between 1 June and 31 August 2013, with no history of international travel in the previous 14 days. Epidemiological, environmental, and traceback investigations were conducted. Of the 631 cases reported in the multistate outbreaks, Texas reported the greatest number of cases, 270 (43%). More than 70 clusters were identified in Texas, four of which were further investigated. One restaurant-associated cluster of 25 case-patients was selected for a case-control study. Consumption of cilantro was most strongly associated with illness on meal date-matched analysis (matched odds ratio 19·8, 95% confidence interval 4·0–∞). All case-patients in the other three clusters investigated also ate cilantro. Traceback investigations converged on three suppliers in Puebla, Mexico. Cilantro was the vehicle of infection in the four clusters investigated; the temporal association of these clusters with the large overall increase in cyclosporiasis cases in Texas suggests cilantro was the vehicle of infection for many other cases. However, the paucity of epidemiological and traceback information does not allow for a conclusive determination; moreover, molecular epidemiological tools for cyclosporiasis that could provide more definitive linkage between case clusters are needed.

Comparative sequence analysis of Cyclospora cayetanensis apicoplast genomes originating from diverse geographical regions

“…Without molecular epidemiologic tools, it can be difficult to link cases to particular food vehicles and sources, thereby hampering the timely implementation of measures to control and prevent outbreaks. The development of molecular methods for the detection and characterization of C. cayetanensis isolates is therefore a priority for US public health agencies [9]. …”

Cyclospora cayetanensis

“…The 2013 multistate outbreaks in the US affected 25 states (primarily Texas, Iowa, and Nebraska) with 631 laboratory confirmed cases of disease. These outbreaks contributed to the largest annual number of reported US cases of cyclosporiasis since 1997 (Abanyie et al, 2013). The 2014 and 2015 multistate epidemics in this country involved 304 and 546 confirmed cases in 19 and 31 states, respectively; most of the cases were reported among Texas residents (CDC, 2014(CDC, , 2015.…”

“…Sporadic outbreaks of cyclosporiasis, including the multistate outbreaks in the USA in 2013-2015 (Abanyie et al, 2013;CDC, 2014CDC, , 2015 and Canada in 2015 (PHAC, 2015), underscore the continued burden of illness this protist presents in developed countries. Cyclosporiasis might have long-term negative consequences since early childhood diarrheal illness could have serious impacts on children's growth and cognitive development and may predispose them to chronic metabolic disease in later life (Guerrant et al, 2013).…”

“…Additional outbreaks of cyclosporiasis in both countries, and Europe were associated with consumption of basil, lettuce, field greens and snow peas (Herwald et al, 1997;Ho et al, 2002;Doller et al, 2002;Hoang et al, 2005;Insulander et al, 2010;Kozak et al, 2013;Gibbs et al, 2013;Abanyie et al, 2015;CDC, 2014CDC, , 2015Buss et al, 2016) (Table 2). In the US, outbreaks occurred in 25 states in the summer of 2013, with most cases in Texas, Iowa, and Nebraska (Abanyie et al, 2013). In June-July 2014 and May-September 2015, epidemics affected 19 and 31 states, respectively; most of the cases were reported from Texas (CDC, 2014(CDC, , 2015.…”

Review of Telemicrobiology

“…cyclposporiasis or trichinellosis) from clinical, environmental, and/or food samples during outbreak investigations. (37, 38) Some areas of the world face constant health threats but lack the expertise that is required to provide optimal diagnostic care. Developing an infrastructure that would enable these areas to gain access to services such as DPDx could greatly improve the areas’ healthcare, but establishing and maintaining front end quality (e.g.…”