Outbreaks Associated with Cantaloupe, Watermelon, and Honeydew in the United States, 1973–2011

Abstract

Fresh fruits and vegetables are an important part of a healthy diet. Melons have been associated with enteric infections. We reviewed outbreaks reported to the Centers for Disease Control and Prevention’s Foodborne Disease Outbreak Surveillance System during 1973–2011 in which the implicated food was a single melon type. We also reviewed published literature and records obtained from investigating agencies. During 1973–2011, 34 outbreaks caused by a single melon type were reported, resulting in 3602 illnesses, 322 hospitalizations, 46 deaths, and 3 fetal losses. Cantaloupes accounted for 19 outbreaks (56%), followed by watermelons (13, 38%) and honeydew (2, 6%). Melon-associated outbreaks increased from 0.5 outbreaks per year during 1973–1991 to 1.3 during 1992–2011. Salmonella was the most common etiology reported (19, 56%), followed by norovirus (5, 15%). Among 13 outbreaks with information available, melons imported from Mexico and Central America were implicated in 9 outbreaks (69%) and domestically grown melons were implicated in 4 outbreaks (31%). The point of contamination was known for 20 outbreaks; contamination occurred most commonly during growth, harvesting, processing, or packaging (13, 65%). Preventive measures focused on reducing bacterial contamination of melons both domestically and internationally could decrease the number and severity of melon-associated outbreaks.

Meta-analysis of the Effects of Sanitizing Treatments on Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes Inactivation in Fresh Produce

“…Since cluster analysis is a multivariate data analysis techniquehence, it requires continuous variables as inputs-it is necessary to first obtain some measurements of the characteristics of each sanitizer in the form of a continuous variable. In a regression analysis of the type (6) adjusted to the whole data from a given sanitizer, the parameter estimates ␤ 0 , ␤ 1 , ␤ 2 , and ␤ 3 can be thought of as the continuous variables characterizing the disinfectant capacity of the sanitizer. This is because for a sanitizer, the higher the intercept ␤ 0 (representing the mean log reduction R at the mean log concentration C, the mean temperature T, and the mean time t), the higher the microbial mean log reduction R. Similarly, a sanitizer with higher slopes ␤ 1 , ␤ 2 , and ␤ 3 will produce a greater mean log reduction R for a given log concentration C, temperature T, and time t, respectively.…”

“…One of the chief concerns related to the safety of these products is their recurrent and increased association with disease outbreaks (3)(4)(5)(6). Epidemiological investigations indicate that Salmonella, pathogenic Escherichia coli, and Listeria monocytogenes stand out as the most important bacterial agents linked to fresh-produce disease outbreaks (3,(5)(6)(7). Recent studies have reported the occurrence and high diversity of these microorganisms in the environment or in close areas of produce farming areas (8)(9)(10)(11)(12)(13).…”

“…Considering the capabilities of the meta-analysis and the significance of Salmonella, pathogenic E. coli, and L. monocytogenes for the microbial safety of fresh produce and for the public health (3,(5)(6)(7), the objective of this study is 4-fold: (i) first, to compile all publicly accessible published findings on the effects of sanitizers on the mean reduction in the log counts of Salmonella spp., E. coli O157:H7, and L. monocytogenes on fresh produce and quantitatively summarize the outcomes by means of meta-analytical models based on mixed-effects linear regressions; (ii) second, to explain a proportion of the total between-study heterogeneity in the reduction of the pathogens' populations by incorporating available study characteristics, such as type of fresh produce, type of sanitizer, concentration, and treatment time and temperature, into the basic meta-analysis model; (iii) third, to assess possible differences in the susceptibilities of Salmonella spp., E. coli O157: H7, and L. monocytogenes to selected sanitizers, as well as differences in the overall microbial log reduction among fresh produce for a given disinfectant treatment; and (iv) finally, to evaluate the effectiveness of the sanitizers to reduce each of the pathogen's populations using a common disinfectant treatment and to propose a classification of sanitizers according to their bactericidal efficacies by means of a meta-analytical dendrogram. The resulting meta-analysis models have the capability to provide overall log reduction estimates for a particular pathogen when using a given sanitizer and sanitizing treatment.…”

Cetylpyridinium chloride direct spray treatments reduce Salmonella on cantaloupe rough surfaces

“…Cases of foodborne illness and illness outbreaks caused by Salmonella and other pathogenic bacteria, associated with consumption of fruits and vegetables from both domestic and imported sources, have increased over the last two decades (Bowen, Fry, Richards, & Beuchat, 2006; Centers for Disease Control & Prevention (CDC), 2013; USFDA, 2003a). Specifically, during 1973–2011, 19 illness outbreaks caused by the consumption of cantaloupes were reported, resulting in 1,012 illnesses and 215 hospitalizations (Walsh, Bennett, Mahovic, & Gould, 2014). Most of the outbreaks have been linked to poor or inappropriate cleaning and sanitation at the packing houses.…”

“…have been implicated in many outbreaks of foodborne illness linked to the consumption of fresh fruits, including cantaloupe melons. And, several serotypes of Salmonella have been responsible for multi‐state illness outbreaks and other illness cases associated with consumption of cantaloupe (Richards & Beuchat, 2004; Walsh et al, 2014). Because Salmonella can attach to rough surfaces and build biofilm complexes, these organisms can be hard to remove using just chlorine and tap water.…”