Food Safety News
For the final day of Food Safety Month, we bring you these popular — and dangerous — myths and their factual counterparts from the Partnership for Food Safety Education.
A norovirus recombinant GII.P4_NewOrleans_2009/GII.4_Sydney_2012 was first detected in Victoria, Australia, in August 2015 at low frequency, and then re-emerged in June 2016, having undergone genetic changes. Analysis of 14 years’ surveillance data from Victoria suggests a typical delay of two to seven months between first detection of a new variant and occurrence of a subsequent epidemic linked to that variant. We consider that the current recombinant strain has the potential to become a pandemic variant.
Food Safety News
Federal health officials have concluded their investigation involving General Mills flour implicated in an E. coli outbreak that sickened at least 63 between December 2015 and now, but they say more people are expected to become ill.
Both the Food and Drug Administration and the Centers for Disease Control and Prevention again urged consumers nationwide to check their homes for the recalled flour and a variety of recalled foods made with it in final outbreak reports posted Thursday.
“Although the outbreak investigation is over, illnesses are expected to continue for some time,” according to the CDC report. “Consumers who don’t know about the recalls could continue to eat the products and get sick. A list of the recalled products and how to identify them is available on the Advice to Consumers page.”
In September 2015, PulseNet, the national molecular subtyping network for foodborne disease surveillance, identified a cluster of Listeria monocytogenes (Listeria) clinical isolates indistinguishable by two-enzyme pulsed-field gel electrophoresis (PFGE) pattern combination and highly related by whole-genome multilocus sequence typing (wgMLST). A case was defined as isolation of Listeria with the outbreak PFGE pattern and highly related by wgMLST with an isolation date on or after July 5, 2015, the isolate date of the earliest case in this cluster.
A standardized Listeria Initiative questionnaire (1) was used to gather information about foods consumed in the 4 weeks before illness from seven persons identified by November 30, 2015, with isolation dates occurring July 5, 2015–October 30, 2015. This tool did not include leafy green vegetables and failed to identify a common source for the infections. During December 2015 and January 2016, eight new or previously interviewed patients or their surrogates participated in open-ended interviews or provided shopper card records, and all reported consuming leafy greens in the month before illness onset. Among these, seven (88%) reported romaine and six (75%) reported spinach, higher than national food consumption estimates of 47% (p = 0.022) and 24% (p = 0.003), respectively (2). Six patients (75%) recalled consuming packaged salad, and three patients (38%) who recalled brands reported packaged salad brands processed by Company A.
The disinfectant and antimicrobial susceptibility profiles of 138 non-O157 Shiga toxin–producing Escherichia coli strains (STECs) from food animals and humans were determined. Antimicrobial resistance (AMR) was moderate (39.1% of strains) in response to 15 antimicrobial agents. Animal strains had a lower AMR prevalence (35.6%) than did human strains (43.9%) but a higher prevalence of the resistance profile GEN-KAN-TET. A decreasing prevalence of AMR was found among animal strains from serogroups O45 > O145 > O121 > O111 > O26 > O103 and among human strains from serogroups O145 > O103 > O26 > O111 > O121 > O45. One animal strain from serogroups O121 and O145 and one human strain from serogroup O26 had extensive drug resistance. A high prevalence of AMR in animal O45 and O121 strains and no resistance or a low prevalence of resistance in human strains from these serogroups suggests a source other than food animals for human exposure to these strains. Among the 24 disinfectants evaluated, all strains were susceptible to triclosan. Animal strains had a higher prevalence of resistance to chlorhexidine than did human strains. Both animal and human strains had a similar low prevalence of low-level benzalkonium chloride resistance, and animal and human strains had similar susceptibility profiles for most other disinfectants. Benzyldimethylammonium chlorides and C10AC were the primary active components in disinfectants DC&R and P-128, respectively, against non-O157 STECs. A disinfectant FS512 MIC ≥ 8 μg/ml was more prevalent among animal O121 strains (61.5%) than among human O121 strains (25%), which may also suggest a source of human exposure to STEC O121 other than food animals. Bacterial inhibition was not dependent solely on pH but was correlated with the presence of dissociated organic acid species and some undissociated acids.
A significant number of pathogens can be transmitted to humans through meat and poultry, and the risks have changed over time. The public health threat posed by some pathogens has diminished, while others have persisted for decades. New, often more virulent strains of existing disease agents continue to emerge, along with previously unknown pathogens such as the Middle East respiratory syndrome coronavirus (MERS-CoV). When such truly new pathogens emerge in one part of the world, many questions remain initially unanswered, including how they are transmitted, which animal species they can infect, whether they may extend their geographic range, and whether transmission through meat and poultry may be possible. MERS-CoV, for instance, is currently emerging in camels and humans in the Middle East; what, if any, risk this virus may pose to the U.S. meat supply going forward is difficult to predict. Some emerging pathogens, such as E. coli O157:H7, have eventually developed into major food safety concerns. For others, such as the hepatitis E virus (HEV), the importance of exposure through meat is still uncertain. Given the dynamic properties of foodborne pathogens, one thing appears certain: New foodborne risks inevitably will develop.
This study reviews microbial hazards and risks in the U.S. meat and poultry supply that have emerged, are emerging, or that evidence suggests may emerge in the future. The study’s goals are to identify factors that favor the occurrence of emerging pathogens (EPs) and pinpoint traits that EPs transmitted through meat and poultry may share; characterize the challenges these pose, be they scientific, technological, or regulatory; and determine mechanisms that might facilitate the expeditious detection, characterization, and control of such EPs.