This document is intended to serve as a reference for everyone interested in the safety of melons by providing a comprehensive list of melon-related outbreaks in the United States.
In recent years, foodborne illness outbreaks have become increasingly associated with produce (Walsh et al. 2014). One such commodity linked to foodborne illness are melons (specifically cantaloupe, honeydew, and watermelon), which are consumed around the world. Melons can be eaten alone or combined with other fruit and vegetables to make salads. Regardless of the way they are prepared, melons are typically consumed raw. This lack of a processing step increases the risk a foodborne pathogen making it to the consumer (Carstens et al. 2019).
While in the field, melons may be in direct contact with the soil, irrigation water, and insects, all of which are a potential source of contamination (Carstens et al. 2019; Walsh et al. 2014). Melons may also becom contaminated with foodborne pathogens during harvesting, packing, shipping, or preparation for consumption. During harvesting, mechanical damage resulting in wounds (e.g., punctures, cracks, bruising) may allow pathogen entry into the melon mesocarp tissue (i.e., edible flesh of the fruit) (US Food and Drug Administration 2013). Pathogen infiltration and adherence at the stem scar tissue (the end of the melon where the vine was removed), especially in cantaloupe, also can be problematic for food safety (US Food and Drug Administration 2013).
The characteristics and maturity of the melons can also influence the susceptibility to foodborne pathogen contamination. The characteristics of the melon rind, specifically the netted surfaces (cantaloupes), create a favorable environment for bacteria to grow and make it difficult to remove pathogens (Fu et al. 2020; Walsh et al. 2014). The maturity of the melon also can play a role in susceptibility because ripe melons may allow for better growth and survival of pathogens on their surfaces (Suslow 1997). Contamination on the surface of a melon may then be able to spread to the inside of the fruit once the melon is cut (Walsh et al. 2014).
This document serves as a reference for those concerned about the safety of melons, including cantaloupe, honeydew, and watermelon in the fresh and fresh-cut market. Outbreaks associated with melons in the United States, Canada, and Europe are highlighted with information regarding the location, pathogen, and incidence of illness. Six tables are presented, representing different melon types (Table 1, cantaloupe; Table 2, honeydew; and Table 3, watermelon), unspecified melon and mixed fruits including melon (Table 4), outbreaks suspected to be associated with different melon types, unspecified melon, and mixed fruits including melon (Table 5), and outbreaks associated with multiple foods including melons (Table 6).
Table 1. Outbreaks of foodborne disease associated with cantaloupe, 1997–2016*
a Pathogens abbreviated and associated with outbreaks include E. (Escherichia), L. (Listeria)
b NR: Not Reported
*Table was last updated on 5-3-2021. The most recent data published by the CDC indicates that there have been no outbreaks since 2016.
Table 2. Outbreaks of foodborne disease associated with honeydew, 2003*
*Table was last updated on 5-3-2021. The most recent data published by the CDC indicates that there have been no outbreaks since 2003.
Table 3. Outbreaks of foodborne disease associated with watermelon, 1950–2017*
a Pathogens abbreviated and associated with outbreaks include E. (Escherichia)
*Table was last updated on 5-3-2021. The most recent data published by the CDC indicates that there have been no outbreaks since 2017.
Table 4. Foodborne Illness Outbreaks Associated with Unspecified Melons and Mixed Fruit (including melon), 1998–2019*
*Table was last updated on 5-3-2021. The most recent data published by the CDC indicates that there have been no outbreaks since 2019.
Table 5. Foodborne illness outbreaks suspected to be associated with cantaloupe, honeydew, or watermelon or with unspecified melons, or mixed fruit (including melon), 1987–2017*
a Pathogens abbreviated and associated with outbreaks include E. (Escherichia)
b NR: Not Reported
*Table was last updated on 5-3-2021. The most recent data published by the CDC indicates that there have been no outbreaks since 2017.
Table 6. Foodborne illness outbreaks associated with multiple foods (including melons), 2000–2016*
a Pathogens abbreviated and associated with outbreaks include E. (Escherichia)
*Table was last updated on 5-3-2021. The most recent data published by the CDC indicates that there have been no outbreaks since 2016.
References
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