Analysis of Outbreak Data Reveals Factors Contributing to Salmonellosis Outbreaks Linked to Cantaloupes

Over the last thirty years, the presence of Salmonella spp. on cantaloupes has been linked to multiple large and deadly foodborne outbreaks in multiple countries. To identify factors associated with the number of cases and risk of severe illness in these outbreaks, information from previous melon-associated salmonellosis outbreaks was analyzed. Data were collected from sixty outbreak investigations. Compared to other melon types, such as watermelon, honeydew, and Galia melon, cantaloupes had the highest public health burden. Cantaloupes were implicated in 43% of reported melon-related outbreaks, 51% of melon-related laboratory-confirmed cases, 54% of melon-related hospitalizations, and 76% of melon-related deaths. In the United States, imported cantaloupes were associated with higher rates of severe salmonellosis and a greater diversity of Salmonella spp. serovars compared to domestically grown cantaloupes. Cantaloupes implicated in outbreaks were equally likely to have been consumed in either private or public settings. Larger outbreaks were associated with the consumption of precut cantaloupe and/or the consumption of cantaloupes in public settings. With the identification of these contributing factors, a literature search was conducted to assess the state of knowledge concerning Salmonella and cantaloupes. Several gaps in the literature were noted and are discussed in the context of reducing the number of illnesses associated with the presence of Salmonella on cantaloupes.