The CDC, several states, and USDA/FSIS are investigating a multistate outbreak of Listeria monocytogenes. While the source of the outbreak was not identified, Whole Genome Sequencing (WGS) showed that bacteria isolated from ill people were closely related genetically. This means that people in this outbreak are more likely to share a common source of infection. At the same time, the Public Health Agency of Canada is also investigating a Listeria monocytogenes outbreak in several Canadian provinces linked to cooked diced chicken. WGS shows that the type of Listeria making people sick in Canada is closely related genetically to the Listeria, making people sick in the United States. As of August 23, 2019, a total of 24 people infected with the outbreak strain of Listeria monocytogenes have been reported from 13 states, with 22 hospitalizations and 2 deaths. In Canada as of August 23, 2019, there have been 7 confirmed cases of Listeria monocytogenes illness with 6 hospitalizations in three provinces: British Columbia (1), Manitoba (1) and Ontario (5). A specific food item, grocery store, or restaurant chain has not been identified as the source of infections in the United States. @ https://www.cdc.gov/listeria/outbreaks/monocytogenes-08-19/index.html
ruth
Multistate Outbreak of Listeria Infections
Dan-W
CNN Reported that Spain’s health ministry had issued an international health warning for an outbreak of listeriosis in Seville province tied to pork meatloaf that has infected 175 people (161 in Andalucia), with another 500 cases pending confirmation. Fifty people remained in hospital by Wednesday, 23 of whom were pregnant women, according to Reuters. A 90-year-old woman has died from the Listeria infection. The outbreak is linked to pork meatloaf, known as Carne mechada, produced by Magrudis S.L. in the southern Spanish province. Spain has informed the World Health Organization (WHO) and the European Commission about the outbreak. There have been no reports of international distribution of implicated products. This should limit the possibility of cases in other countries. At the beginning of August a Listeria outbreak in the UK had killed six people who had eaten contaminated hospital food. @ https://www.cnn.com/2019/08/22/health/spain-listeria-alert-scli-intl/index.html
Spain’s health ministry has issued an international health warning over a listeria outbreak that has infected 175 people.
ruth
The Canadian food inspection Agency (CFIA) issued an update after expanding Listeria monocytogenes outbreak related to the U.S. company Tip Top Poultry. CFIA has issued a recall (August 18) to Rosemount brand cooked diced chicken. Now another recall, this one for Reuven International Ltd. brand Natural Proportion Cooked Chicken Meat (Diced) and Sysco brand Natural Proportions Cooked Shredded Chicken was issued. The additional products were identified during the CFIA’s food safety investigation of an outbreak that was initiated due to an increase of Listeria illnesses that were reported in June 2019. The recalled products were distributed nationally to hotels, restaurants, hospitals, nursing homes and retail outlets, the CFIA said. The products have been sold in British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, Newfoundland and Labrador and may have been distributed to other provinces and territories. Both the Reuven and Sysco products are in the 4.54-kilogram package with pack dates of Jan. 21, 2019. @ https://www.inspection.gc.ca/about-the-cfia/newsroom/food-recall-warnings/complete-listing/2019-08-21/eng/1566441064966/1566441070819
The food recall warning issued on August, 18, 2019 has been updated to include additional product information.
Doug-B
In the September 2019 issue of Applied and Environmental Microbiology, an article was published on a study investigating the microbial dynamics in multispecies biofilms of Escherichia coli O157:H7 strain 1934 (O157) or Salmonella enterica serovar Typhimurium ATCC 14028 (ST) and 40 strains of meat processing surface bacteria (MPB). Biofilms of O157 or ST with/without MPB were developed on stainless steel coupons at 15°C for up to 6 days. In suspensions, levels of O157 and ST were ∼2 log higher in single-species than in multispecies cultures on both sampling days. ST was 3 log higher in single-species than in multispecies biofilms. A similar trend, though to a lesser extent, was observed for O157 in biofilms on day 2 but not on day 6. No difference (P > 0.05) in bacterial counts was noted for the two MPB-pathogen co-cultures at any time during incubation. Results of this study demonstrate that Salmonella enterica serovar Typhimurium and E. coli O157:H7 can integrate into biofilms when co-cultured with bacteria from meat plant processing surfaces. However, the degree of biofilm formation for both pathogens was substantially reduced in the presence of the competing microbiota, with S. Typhimurium more greatly affected than E. coli O157:H7. The expression of extracellular determinants such as curli and cellulose appears to be less important for biofilm formation of the pathogens in multispecies cultures than in monoculture. In contrast to previous reports regarding food processing surface bacteria, data collected here also demonstrate that facultative anaerobes may have a competitive edge over strict aerobes in establishing multispecies biofilms. @ https://aem.asm.org/content/85/17/e01123-19
This study investigated the microbial dynamics in multispecies biofilms of Escherichia coli O157:H7 strain 1934 (O157) or Salmonella enterica serovar Typhimurium ATCC 14028 (ST) and 40 strains of meat processing surface bacteria (MPB). Biofilms of O157 or ST with/without MPB were developed on stainless steel coupons at 15°C for up to 6 days. Bacteria in suspensions (inoculum, days 2 and 6) and biofilms (days 2 and 6) were enumerated by plating. The composition of multispecies cultures was determined by 16S rRNA gene sequencing. In suspensions, levels of O157 and ST were ∼2 log higher in single-species than in multispecies cultures on both sampling days. ST was 3 log higher in single-species than in multispecies biofilms. A similar trend, though to a lesser extent, was observed for O157 in biofilms on day 2 but not on day 6. No difference ( P > 0.05) in bacterial counts was noted for the two MPB-pathogen cocultures at any time during incubation. Bacterial diversity in multispecies cultures decreased with incubation time, irrespective of the pathogen or culture type. The changes in the relative abundance of MPB were similar for the two MPB-pathogen cocultures, though different interbacterial interactions were noted. Respective fractions of ST and O157 were 2.1% and 0.97% initially and then 0.10% and 0.07% on day 2, and 0.60% and 0.04% on day 6. The relative proportions of facultative anaerobes in both multispecies cultures were greater in both suspensions and biofilms than in the inoculum. Citrobacter , Hafnia , Aeromonas , and Carnobacterium predominated in biofilms but not always in the planktonic cultures.
IMPORTANCE Results of this study demonstrate that Salmonella enterica serovar Typhimurium and E. coli O157:H7 can integrate into biofilms when cocultured with bacteria from meat plant processing surfaces. However, the degree of biofilm formation for both pathogens was substantially reduced in the presence of the competing microbiota, with S. Typhimurium more greatly affected than E. coli O157:H7. The expression of extracellular determinants such as curli and cellulose appears to be less important for biofilm formation of the pathogens in multispecies cultures than in monoculture. In contrast to previous reports regarding food processing surface bacteria, data collected here also demonstrate that facultative anaerobes may have a competitive edge over strict aerobes in establishing multispecies biofilms. It would be important to take into account the presence of background bacteria when evaluating the potential persistence of a pathogen in food processing facilities.