Food Poisoning Bulletin
A Chinese New Year banquet in Philadelphia’s Chinatown triggered one of the largest food poisoning outbreaks in the city’s history, according to Philly.com. Nearly 100 lawyers and law students who attended the banquet were sickened.
There were 250 guests at the Feb. 27 celebration at Joy Tsin Lau, a dim sum restaurant. Two days later, dozens of them fell ill, some ended up in the emergency room, according to the report.
|Name of Importer
|Product name and Description
||Product name: Smoked salmon
Manufacturer: Polyfood Food Service Co Ltd
Weight: 100g / 200g / 227g per pack
Date of Manufacture: March 17, 2015
Use by dates: April 2, 2015 / April 9, 2015
|Reason For Issuing Alert
– The CFS received a notification from the Macao authorities that the batch of smoked salmon imported from Hong Kong was contaminated with Listeria monocytogenes.
– Listeria monocytogenes can be easily destroyed by cooking but can survive and multiply at refrigerator temperatures. Most healthy individuals do not develop symptoms or only have mild symptoms like fever, muscle pain, headache, nausea, vomiting or diarrhoea when infected. However, severe complications such as septicemia, meningitis or even death may occur in newborns, elderly and those with a weaker immune system. Although infected pregnant women may just experience mild symptoms generally, the infection of Listeria monocytogenes may cause miscarriage, infant death, preterm birth, or severe infection in the newborns.
A salmonella outbreak at Kirkby takeaway Woks Cooking has been linked to German eggs and poor hygiene.
Health bosses have completed their final investigations into the fast food outlet which was shut down by Knowsley council last July but opened again in August and is now under new management.
The report by Public Health England (PHE) confirms food safety experts have found signs that the salmonella illnesses at Woks Cooking, as well as a series of other cases across Europe, were linked to eggs from a German supplier.
Applied and Environmental Microbiology
The food-borne pathogenic bacterium Listeria is known for relatively low morbidity and high mortality rates, reaching up to 25 to 30%. Listeria is a hardy organism, and its control in foods represents a significant challenge. Many naturally occurring compounds, including the bacteriocin nisin and a number of plant essential oils, have been widely studied and are reported to be effective as antimicrobial agents against spoilage and pathogenic microorganisms. The aim of this study was to investigate the ability of semipurified preparations (SPP) containing either nisin A or an enhanced bioengineered derivative, nisin V, alone and in combination with low concentrations of the essential oils thymol, carvacrol, and trans-cinnamaldehyde, to control Listeria monocytogenes in both laboratory media and model food systems. Combinations of nisin V-containing SPP (25 μg/ml) with thymol (0.02%), carvacrol (0.02%), or cinnamaldehyde (0.02%) produced a significantly longer lag phase than any of the essential oil-nisin A combinations. In addition, the log reduction in cell counts achieved by the nisin V-carvacrol or nisin V-cinnamaldehyde combinations was twice that of the equivalent nisin A-essential oil treatment. Significantly, this enhanced activity was validated in model food systems against L. monocytogenes strains of food origin. We conclude that the fermentate form of nisin V in combination with carvacrol and cinnamaldehyde offers significant advantages as a novel, natural, and effective means to enhance food safety by inhibiting food-borne pathogens such as L. monocytogenes.
Applied and Environmental Microbiology
The formation of bacterial spoilage communities in food is influenced by both extrinsic and intrinsic environmental factors. Although many reports describe how these factors affect bacterial growth, much less is known about interactions among bacteria, which may influence community structure. This study investigated interactions among representative species of bacteria isolated from vacuum-packaged (VP) beef. Thirty-nine effectors and 20 target isolates were selected, representing 10 bacterial genera: Carnobacterium, Pseudomonas, Hafnia, Serratia, Yersinia, Rahnella, Brochothrix, Bacillus, Leuconostoc, and Staphylococcus. The influence of live effectors on growth of target isolates was measured by spot-lawn agar assay and also in liquid culture medium broth using live targets and effector cell-free supernatants. Inhibition on agar was quantified by diameter of inhibition zone and in broth by measuring detection time, growth rate, and maximum population density. A number of interactions were observed, with 28.6% of isolates inhibiting and 4.2% promoting growth. The majority of Pseudomonas isolates antagonized growth of approximately one-half of target isolates. Two Bacillus spp. each inhibited 16 targets. Among lactic acid bacteria (LAB), Carnobacterium maltaromaticum inhibited a wider range of isolates compared to other LAB. The majority of effector isolates enhancing target isolate growth were Gram-negative, including Pseudomonas spp. and Enterobacteriaceae. These findings markedly improve the understanding of potential interactions among spoilage bacteria, possibly leading to more mechanistic descriptions of bacterial community formation in VP beef and other foods.
Applied and Environmental Microbiology
Human norovirus (NoV) is the leading cause of foodborne disease in the United States, and epidemiological studies have shown that fresh produce is one of the major vehicles for the transmission of human NoV. However, the mechanisms of norovirus contamination and persistence in fresh produce are poorly understood. The objective of this study is to determine whether human NoV surrogates, murine norovirus (MNV-1) and Tulane virus (TV), can attach and become internalized and disseminated in strawberries grown in soil. The soil of growing strawberry plants was inoculated with MNV-1 and TV at a level of 108 PFU/plant. Leaves and berries were harvested over a 14-day period, and the viral titer was determined by plaque assay. Over the course of the study, 31.6% of the strawberries contained internalized MNV-1, with an average titer of 0.81 ± 0.33 log10 PFU/g. In comparison, 37.5% of strawberries were positive for infectious TV, with an average titer of 1.83 ± 0.22 log10 PFU/g. A higher percentage (78.7%) of strawberries were positive for TV RNA, with an average titer of 3.15 ± 0.51 log10 RNA copies/g as determined by real-time reverse transcriptase quantitative PCR (RT-qPCR). In contrast, no or little virus internalization and dissemination were detected when TV was inoculated into bell peppers grown in soil. Collectively, these data demonstrate (i) virally contaminated soils can lead to the internalization of virus via plant roots and subsequent dissemination to the leaf and fruit portions of growing strawberry plants and (ii) the magnitude of internalization is dependent on the type of virus and plant.
Food Safety News
The state with the largest retail sales of raw milk in the United States is warning consumers that the consumption of unpasteurized (raw) dairy products may cause serious illness.
The warning from Dr. Karen Smith, director of the California Department of Public Health (CDPH) and State Health Officer, was issued because six Northern California residents have recently been diagnosed with campylobacteriosis, a bacterial infection that can come from consuming contaminated raw milk.
A recent investigation conducted by CDPH identified multiple bottles of Claravale Farm raw milk that tested positive for Campylobacter. Under the direction of the California Department of Food and Agriculture (CDFA), Claravale Farm initiated a recall of the affected product.
California, where the sale of raw milk at the retail level is legal, continued with a public health warning that states: