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Fichant A, Lanceleur R, Hachfi S, Brun-Barale A, Blier AL, Firmesse O, Gallet A, Fessard V, Bonis M. New Approach Methods to Assess the Enteropathogenic Potential of Strains of the Bacillus cereus Group, including Bacillus thuringiensis. Foods 2024; 13:1140. [PMID: 38672813 PMCID: PMC11048917 DOI: 10.3390/foods13081140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 04/03/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024] Open
Abstract
Bacillus cereus (Bc) is a wide group of Gram-positive and spore-forming bacteria, known to be the etiological agents of various human infections, primarily food poisoning. The Bc group includes enteropathogenic strains able to germinate in the digestive tract and to produce enterotoxins such as Nhe, Hbl, and CytK. One species of the group, Bacillus thuringiensis (Bt), has the unique feature of producing insecticidal crystals during sporulation, making it an important alternative to chemical pesticides to protect crops from insect pest larvae. Nevertheless, several studies have suggested a link between the ingestion of pesticide strains and human cases of food poisoning, calling their safety into question. Consequently, reliable tools for virulence assessment are worth developing to aid decision making in pesticide regulation. Here, we propose complementary approaches based on two biological models, the human intestinal Caco-2 cell line and the insect Drosophila melanogaster, to assess and rank the enteric virulence potency of Bt strains in comparison with other Bc group members. Using a dataset of 48 Bacillus spp. strains, we showed that some Bc group strains, including Bt, were able to induce cytotoxicity in Caco-2 cells with concomitant release of IL-8 cytokine, a landmark of pro-inflammatory response. In the D. melanogaster model, we were able to sort a panel of 39 strains into four different classes of virulence, ranging from no virulence to strong virulence. Importantly, for the most virulent strains, mortality was associated with a loss of intestinal barrier integrity. Interestingly, although strains can share a common toxinotype, they display different degrees of virulence, suggesting the existence of specific mechanisms of virulence expression in vivo in the intestine.
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Affiliation(s)
- Arnaud Fichant
- Laboratory for Food Safety, University Paris-Est, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), 94700 Maisons-Alfort, France; (A.F.); (O.F.)
- Université Côte d’Azur, CNRS, INRAE, ISA, 06903 Sophia-Antipolis, France; (S.H.); (A.B.-B.); (A.G.)
| | - Rachelle Lanceleur
- Fougères Laboratory, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), 35306 Fougères, France; (R.L.); (A.-L.B.); (V.F.)
| | - Salma Hachfi
- Université Côte d’Azur, CNRS, INRAE, ISA, 06903 Sophia-Antipolis, France; (S.H.); (A.B.-B.); (A.G.)
| | - Alexandra Brun-Barale
- Université Côte d’Azur, CNRS, INRAE, ISA, 06903 Sophia-Antipolis, France; (S.H.); (A.B.-B.); (A.G.)
| | - Anne-Louise Blier
- Fougères Laboratory, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), 35306 Fougères, France; (R.L.); (A.-L.B.); (V.F.)
| | - Olivier Firmesse
- Laboratory for Food Safety, University Paris-Est, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), 94700 Maisons-Alfort, France; (A.F.); (O.F.)
| | - Armel Gallet
- Université Côte d’Azur, CNRS, INRAE, ISA, 06903 Sophia-Antipolis, France; (S.H.); (A.B.-B.); (A.G.)
| | - Valérie Fessard
- Fougères Laboratory, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), 35306 Fougères, France; (R.L.); (A.-L.B.); (V.F.)
| | - Mathilde Bonis
- Laboratory for Food Safety, University Paris-Est, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), 94700 Maisons-Alfort, France; (A.F.); (O.F.)
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2
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Leong SS, Korel F, King JH. Bacillus cereus: A review of "fried rice syndrome" causative agents. Microb Pathog 2023; 185:106418. [PMID: 37866551 DOI: 10.1016/j.micpath.2023.106418] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 10/19/2023] [Accepted: 10/19/2023] [Indexed: 10/24/2023]
Abstract
"Fried rice syndrome" originated from the first exposure to a fried rice dish contaminated with Bacillus cereus. This review compiles available data on the prevalence of B. cereus outbreak cases that occurred between 1984 and 2019. The outcome of B. cereus illness varies dramatically depending on the pathogenic strain encounter and the host's immune system. B. cereus causes a self-limiting, diarrheal illness caused by heat-resistant enterotoxin proteins, and an emetic illness caused by the deadly toxin named cereulide. The toxins together with their extrinsic factors are discussed. The possibility of more contamination of B. cereus in protein-rich food has also been shown. Therefore, the aim of this review is to summarize the available data, focusing mainly on B. cereus physiology as the causative agent for "fried rice syndrome." This review emphasizes the prevalence of B. cereus in starchy food contamination and outbreak cases reported, the virulence of both enterotoxins and emetic toxins produced, and the possibility of contaminated in protein-rich food. The impact of emetic or enterotoxin-producing B. cereus on public health cannot be neglected. Thus, it is essential to constantly monitor for B. cereus contamination during food handling and hygiene practices for food product preparation.
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Affiliation(s)
- Sui Sien Leong
- Department of Animal Sciences and Fishery, Faculty of Agricultural and Forestry Sciences, Universiti Putra Malaysia, Nyabau Road, Bintulu, 97008, Sarawak, Malaysia; Institute of Ecosystem Science Borneo, Universiti Putra Malaysia Bintulu Sarawak Campus, Nyabau Road, Bintulu, 97008, Sarawak, Malaysia.
| | - Figen Korel
- Food Engineering Department, Faculty of Engineering, Izmir Institute of Technology, Urla, 35430, İzmir, Turkey
| | - Jie Hung King
- Department of Crop Science, Faculty of Agricultural and Forestry Sciences, Universiti Putra Malaysia, Nyabau Road, Bintulu, 97008, Sarawak, Malaysia
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3
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Bacillus cereus Invasive Infections in Preterm Neonates: an Up-to-Date Review of the Literature. Clin Microbiol Rev 2022; 35:e0008821. [PMID: 35138121 PMCID: PMC8826972 DOI: 10.1128/cmr.00088-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus cereus group species are widespread, Gram-positive, spore-forming environmental bacteria. B. cereus sensu stricto is one of the major causes of food poisoning worldwide. In high-risk individuals, such as preterm neonates, B. cereus infections can cause fatal infections. It is important to note that the phenotypic identification methods commonly used in clinical microbiology laboratories make no distinction between B. cereus sensu stricto and the other members of the group (Bacillus anthracis excluded). As a result, all the invasive infections attributed to B. cereus are not necessarily due to B. cereus sensu stricto but likely to other closely related species of the B. cereus group. Next-generation sequencing (NGS) should be used to characterize the whole genome of the strains belonging to the B. cereus group. This could confirm whether the strains involved in previously reported B. cereus invasive infections preferentially belong to formerly known or emerging individual species. Moreover, infections related to B. cereus group species have probably been overlooked, since their isolation in human bacteriological samples has for a long time been regarded as an environmental contaminant of the cultures. Recent studies have questioned the emergence or reemergence of B. cereus invasive infections in preterm infants. This review reports our current understanding of B. cereus infections in neonates, including taxonomical updates, microbiological characteristics, bacterial identification, clinical features, host-pathogen interactions, environmental sources of contamination, and antimicrobial resistance.
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4
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Zhang R, Zhuang Y, Xiao ZH, Li CY, Zhang F, Huang WQ, Zhang M, Peng XM, Liu C. Diagnosis and Surveillance of Neonatal Infections by Metagenomic Next-Generation Sequencing. Front Microbiol 2022; 13:855988. [PMID: 35401464 PMCID: PMC8989347 DOI: 10.3389/fmicb.2022.855988] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 03/07/2022] [Indexed: 12/21/2022] Open
Abstract
Microbial infections cause significant morbidity and mortality in neonates. Metagenomic next-generation sequencing is a hypothesis-free and culture-free test that enables broad identification of pathogens and antimicrobial resistance genes directly from clinical samples within 24 h. In this study, we used mNGS for etiological diagnosis and monitoring the efficacy of antibiotic treatment in a cohort of neonatal patients with severe infections. The median age was 19.5 (3–52) days, median gestational age was 37.96 (31–40+3) weeks, and the median birth weight was 3,261 (1,300–4,300) g. The types of infectious diseases included pneumonia, sepsis, and meningitis. mNGS reported microbial findings in all cases, which led to changes in antibiotic treatment. These included cases of Mycobacterium tuberculosis, Legionella pneumophila, and Bacillus cereus. Eight of ten infants recovered after antibiotic adjustment and showed normal development during follow-up. On the other hand, neurological retardation was seen in two infants with meningitis. mNGS enabled etiological diagnosis and guided antibiotic therapy when all conventional methods failed to discover the culprit. It has the potential to cut down the overall cost and burden of disease management in neonatal infections.
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Affiliation(s)
- Rong Zhang
- Department of Neonatology, Hunan Children’s Hospital, Changsha, China
| | - Yan Zhuang
- Department of Neonatology, Hunan Children’s Hospital, Changsha, China
| | - Zheng-hui Xiao
- Department of Emergency, Hunan Children’s Hospital, Changsha, China
| | - Cai-yun Li
- Department of Medical, Hangzhou Matridx Biotechnology Co., Ltd., Hangzhou, China
| | - Fan Zhang
- Department of Neonatology, Hunan Children’s Hospital, Changsha, China
| | - Wei-qing Huang
- Department of Neonatology, Hunan Children’s Hospital, Changsha, China
| | - Min Zhang
- Department of Neonatology, Hunan Children’s Hospital, Changsha, China
| | - Xiao-Ming Peng
- Department of Neonatology, Hunan Children’s Hospital, Changsha, China
- *Correspondence: Xiao-Ming Peng,
| | - Chao Liu
- Department of Medical, Hangzhou Matridx Biotechnology Co., Ltd., Hangzhou, China
- Chao Liu,
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5
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Mallardi D, Piemontese P, Liotto N, Colombo RM, Dodaro A, Schiavello A, Tabasso C, Plevani L, Bezze E, Menis C, Roggero P, Mosca F. New Operating Approach to Limit Bacillus Cereus Contamination of Donor Human Milk. J Hum Lact 2022; 38:102-107. [PMID: 33745375 DOI: 10.1177/08903344211002563] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Domenica Mallardi
- 9339 NICU, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Pasqua Piemontese
- 9339 NICU, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Nadia Liotto
- 9339 NICU, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Rosaria M Colombo
- 9339 Unit of Microbiology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Antonella Dodaro
- 9339 Unit of Microbiology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | | | - Chiara Tabasso
- 9339 NICU, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Laura Plevani
- 9339 NICU, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Elena Bezze
- 9339 NICU, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Camilla Menis
- 9339 NICU, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Department of Clinical Science and Community Health, University of Milan, Milan, Italy
| | - Paola Roggero
- 9339 NICU, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Department of Clinical Science and Community Health, University of Milan, Milan, Italy
| | - Fabio Mosca
- 9339 NICU, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,Department of Clinical Science and Community Health, University of Milan, Milan, Italy
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6
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Kavanaugh DW, Porrini C, Dervyn R, Ramarao N. The pathogenic biomarker alcohol dehydrogenase protein is involved in Bacillus cereus virulence and survival against host innate defence. PLoS One 2022; 17:e0259386. [PMID: 34982789 PMCID: PMC8726459 DOI: 10.1371/journal.pone.0259386] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 10/18/2021] [Indexed: 11/19/2022] Open
Abstract
Bacillus cereus is a spore forming bacteria recognized among the leading agents responsible for foodborne outbreaks in Europe. B. cereus is also gaining notoriety as an opportunistic human pathogen inducing local and systemic infections. The real incidence of such infection is likely underestimated and information on genetic and phenotypic characteristics of the incriminated strains is generally scarce. We have recently analyzed a large strain collection of varying pathogenic potential. Screening for biomarkers to differentiate among clinical and non-clinical strains, a gene encoding an alcohol dehydrogenase-like protein was identified among the leading candidates. This family of proteins has been demonstrated to be involved in the virulence of several bacterial species. The relevant gene was knocked out to elucidate its function with regards to resistance to host innate immune response, both in vitro and in vivo. Our results demonstrate that the adhB gene plays a significant role in resistance to nitric oxide and oxidative stress in vitro, as well as its pathogenic ability with regards to in vivo toxicity. These properties may explain the pathogenic potential of strains carrying this newly identified virulence factor.
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Affiliation(s)
- Devon W. Kavanaugh
- Micalis Institute, INRAE, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Constance Porrini
- Micalis Institute, INRAE, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Rozenn Dervyn
- Micalis Institute, INRAE, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Nalini Ramarao
- Micalis Institute, INRAE, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
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7
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ZHANG R, ZHANG Y, ZHANG T, XU M, WANG H, ZHANG S, ZHANG T, ZHOU W, SHI G. Establishing a MALDI-TOF-TOF-MS method for rapid identification of three common Gram-positive bacteria (Bacillus cereus, Listeria monocytogenes, and Micrococcus luteus) associated with foodborne diseases. FOOD SCIENCE AND TECHNOLOGY 2022. [DOI: 10.1590/fst.117021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Rui ZHANG
- Hebei Food Inspection and Research Institute, China
| | - Yalun ZHANG
- Hebei Food Inspection and Research Institute, China
| | - Tao ZHANG
- Hebei Food Inspection and Research Institute, China
| | - Miaomiao XU
- Hebei Food Inspection and Research Institute, China
| | - Hui WANG
- Hebei Food Inspection and Research Institute, China
| | - Shuang ZHANG
- Hebei Food Inspection and Research Institute, China
| | - Tonghe ZHANG
- Hebei Food Inspection and Research Institute, China
| | - Wei ZHOU
- Hebei Food Inspection and Research Institute, China
| | - Guohua SHI
- Hebei Food Inspection and Research Institute, China
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8
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Gamage NW, Bamforth J, Ashfaq T, Bernard K, Gräfenhan T, Walkowiak S. Profiling of Bacillus cereus on Canadian grain. PLoS One 2021; 16:e0259209. [PMID: 34735500 PMCID: PMC8568128 DOI: 10.1371/journal.pone.0259209] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 10/14/2021] [Indexed: 11/18/2022] Open
Abstract
Microorganisms that cause foodborne illnesses challenge the food industry; however, environmental studies of these microorganisms on raw grain, prior to food processing, are uncommon. Bacillus cereus sensu lato is a diverse group of bacteria that is common in our everyday environment and occupy a wide array of niches. While some of these bacteria are beneficial to agriculture due to their entomopathogenic properties, others can cause foodborne illness; therefore, characterization of these bacteria is important from both agricultural and food safety standpoints. We performed a survey of wheat and flax grain samples in 2018 (n = 508) and 2017 (n = 636) and discovered that B. cereus was present in the majority of grain samples, as 56.3% and 85.2%, in two years respectively. Whole genome sequencing and comparative genomics of 109 presumptive B. cereus isolates indicates that most of the isolates were closely related and formed two genetically distinct groups. Comparisons to the available genomes of reference strains suggested that the members of these two groups are not closely related to strains previously reported to cause foodborne illness. From the same data set, another, genetically more diverse group of B. cereus was inferred, which had varying levels of similarity to previously reported strains that caused disease. Genomic analysis and PCR amplification of genes linked to toxin production indicated that most of the isolates carry the genes nheA and hbID, while other toxin genes and gene clusters, such as ces, were infrequent. This report of B. cereus on grain from Canada is the first of its kind and demonstrates the value of surveillance of bacteria naturally associated with raw agricultural commodities such as cereal grain and oilseeds.
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Affiliation(s)
| | - Janice Bamforth
- Canadian Grain Commission, Government of Canada, Winnipeg, Canada
| | - Tehreem Ashfaq
- Canadian Grain Commission, Government of Canada, Winnipeg, Canada
| | - Kathryn Bernard
- Public Health Agency of Canada, National Microbiology Laboratory, Government of Canada, Winnipeg, Canada
| | - Tom Gräfenhan
- Canadian Grain Commission, Government of Canada, Winnipeg, Canada
- Public Health Agency of Canada, National Microbiology Laboratory, Government of Canada, Winnipeg, Canada
- * E-mail: (TG); (SW)
| | - Sean Walkowiak
- Canadian Grain Commission, Government of Canada, Winnipeg, Canada
- * E-mail: (TG); (SW)
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Complete Circular Genome Sequences of Three Bacillus cereus Group Strains Isolated from Positive Blood Cultures from Preterm and Immunocompromised Infants Hospitalized in France. Microbiol Resour Announc 2021; 10:e0059721. [PMID: 34647805 PMCID: PMC8515894 DOI: 10.1128/mra.00597-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We report here the complete genome sequences of three Bacillus cereus group strains isolated from blood cultures from premature and immunocompromised infants hospitalized in intensive care units in three French hospitals. These complete genome sequences were obtained from a combination of Illumina HiSeq X Ten short reads and Oxford Nanopore MinION long reads.
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10
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Investigation of a cluster of Bacillus cereus bacteremia in neonatal care units. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2021; 55:494-502. [PMID: 34340907 DOI: 10.1016/j.jmii.2021.07.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 07/01/2021] [Accepted: 07/10/2021] [Indexed: 11/23/2022]
Abstract
BACKGROUND Bacillus cereus is a well-known pathogen for self-limited foodborne illness, and rarely an opportunistic pathogen associated with invasive infections among immunocompromised patients. Nosocomial outbreaks have been rarely reported. METHODS Between August and November 2019, four preterm neonates in neonatal care units of a medical center developed late-onset B. cereus bacteremia. An investigation was carried out. Forty-eight environmental specimens were obtained from these neonatal units, skin surface and environmental objects of Patient 4 for the detection of this organism 19 days after the onset of illness of Patient 4. B. cereus isolates from Patient 4, five unrelated patients and environmental objects if identified were further characterized by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). RESULTS All four infants survived after vancomycin-containing treatment. Patient 4 developed diffuse cerebritis, brain abscess with severe neurologic sequelae. Of the 48 environmental samplings, 26 specimens showed positive for B. cereus, with one major clone (sequence type 365) accounting for 73%. The isolate from Patient 4 (ST427) was identical to one isolate collected from environmental objects in the same unit. After extensive cleaning of the environment and re-institution of the sterilization procedure of hospital linens, which was ceased since two months before the outbreak, no more cases was identified in these units for at least one year. CONCLUSIONS We documented a cluster of B. cereus bacteremia involving four preterm infants, which might be associated with cessation of the procedure for linen sterilization and was successfully controlled by re-institution of this procedure.
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Shea S, Paniz-Mondolfi A, Sordillo E, Nowak M, Dekio F. Florid Bacillus cereus Infection of the Placenta Associated With Intrauterine Fetal Demise. Pediatr Dev Pathol 2021; 24:361-365. [PMID: 33729850 DOI: 10.1177/1093526621999026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Bacillus cereus is a gram-positive, rod-shaped bacterium that is commonly implicated in foodborne illness but has also become increasingly recognized as a source of serious non-gastrointestinal infections, including sepsis, meningitis, and pneumonia. Non-gastrointestinal B. cereus infections have been identified in children, especially in neonates; however, there are no previously described cases of fetal demise associated with B. cereus placental infection. We present a case of acute chorioamnionitis-related intrauterine fetal demise of twin A at 17 weeks gestation, noted two days after selective termination of twin B. Histological examination revealed numerous gram-positive bacilli in placental tissue, as well as fetal vasculature, in the setting of severe acute necrotizing chorioamnionitis and subchorionitis, intervillous abscesses, acute villitis, and peripheral acute funisitis. Cultures of maternal blood and placental tissue both yielded growth of B. cereus. This case underscores the importance of B. cereus as a human pathogen, and specifically demonstrates its potential as an agent of severe intraamniotic and placental infection with poor outcomes for the fetus.
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Affiliation(s)
- Stephanie Shea
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York
| | | | - Emilia Sordillo
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Michael Nowak
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Fumiko Dekio
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, New York
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12
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Kavanaugh DW, Glasset B, Dervyn R, Guérin C, Plancade S, Herbin S, Brisabois A, Nicolas P, Ramarao N. New genetic biomarkers to differentiate non-pathogenic from clinically relevant Bacillus cereus strains. Clin Microbiol Infect 2021; 28:137.e1-137.e8. [PMID: 34111580 DOI: 10.1016/j.cmi.2021.05.035] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 05/18/2021] [Accepted: 05/22/2021] [Indexed: 01/14/2023]
Abstract
OBJECTIVES Bacillus cereus is responsible for food poisoning and rare but severe clinical infections. The pathogenicity of strains varies from harmless to lethal strains. However, there are currently no markers, either alone or in combination, to differentiate pathogenic from non-pathogenic strains. The objective of the study was to identify new genetic biomarkers to differentiate non-pathogenic from clinically relevant B. cereus strains. METHODS A first set of 15 B. cereus strains were compared by RNAseq. A logistic regression model with lasso penalty was applied to define combination of genes whose expression was associated with strain pathogenicity. The identified markers were checked for their presence/absence in a collection of 95 B. cereus strains with varying pathogenic potential (food-borne outbreaks, clinical and non-pathogenic). Receiver operating characteristic area under the curve (AUC) analysis was used to determine the combination of biomarkers, which best differentiate between the "disease" versus "non-disease" groups. RESULTS Seven genes were identified during the RNAseq analysis with a prediction to differentiate between pathogenic and non-pathogenic strains. The validation of the presence/absence of these genes in a larger collection of strains coupled with AUC prediction showed that a combination of four biomarkers was sufficient to accurately discern clinical strains from harmless strains, with an AUC of 0.955, sensitivity of 0.9 and specificity of 0.86. CONCLUSIONS These new findings help in the understanding of B. cereus pathogenic potential and complexity and may provide tools for a better assessment of the risks associated with B. cereus contamination to improve patient health and food safety.
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Affiliation(s)
| | | | - Rozenn Dervyn
- INRAE, Micalis, University Paris-Sacly, Jouy-en-Josas, France
| | - Cyprien Guérin
- INRAE, MaIAGE, Université Paris-Saclay, Jouy-en-Josas, France
| | - Sandra Plancade
- INRAE, MaIAGE, Université Paris-Saclay, Jouy-en-Josas, France
| | - Sabine Herbin
- ANSES, Universtité Paris-Est, Laboratory of Food Safety, Maisons-Alfrot, France
| | - Anne Brisabois
- ANSES, Universtité Paris-Est, Laboratory of Food Safety, Maisons-Alfrot, France
| | - Pierre Nicolas
- INRAE, MaIAGE, Université Paris-Saclay, Jouy-en-Josas, France
| | - Nalini Ramarao
- INRAE, Micalis, University Paris-Sacly, Jouy-en-Josas, France.
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13
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Amin HM, Tawfick MM. High Risk of Potential Diarrheagenic Bacillus cereus in Diverse Food Products in Egypt. J Food Prot 2021; 84:1033-1039. [PMID: 33465240 DOI: 10.4315/jfp-20-384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 01/11/2021] [Indexed: 11/11/2022]
Abstract
ABSTRACT Bacillus cereus is one of the important foodborne pathogens that can be found in various foodstuffs, causes diarrheal and/or emetic syndromes, and can cause severe systemic diseases that may lead to death. This study was conducted to evaluate the prevalence, antimicrobial susceptibility profile, pathogenic potential, and genotypic diversity of B. cereus isolates recovered from diverse food products collected from markets in Cairo, Egypt. Of 165 food samples investigated in this study, 39 (24%) were positive for B. cereus, with contamination levels of 2 to 6 log CFU/g or mL and a higher prevalence of levels >3 log CFU. Antimicrobial susceptibility testing revealed that the B. cereus isolates were fully sensitive to all tested antimicrobial agents except β-lactams. The pathogenic potential of the 39 B. cereus isolates was assessed by detecting and profiling genes encoding virulence factors or toxins: the chromosomal genes hblA, bceT, plc, sph, nheA, entFM, and cytK associated with the diarrheal syndrome and the plasmid ces gene associated with the emetic syndrome. The most frequently detected genes were hblA, nheA, and entFM. All isolates harbored more than one of the diarrheal enterotoxin genes, and the genetic profile hblA-bceT-nheA-entFM-cytK-plc-sph was the most prevalent (20 of 39 isolates). The emetic toxin gene ces was not detected in any isolate. Enterobacterial repetitive intergenic consensus analysis of the 20 B. cereus isolates harboring the most prevalent genetic profile revealed that these isolates were genetically distinct, with a Simpson index of diversity value of 0.989. These findings provide useful information for public health management and serve as a warning of the potential risk of diarrheagenic B. cereus in diverse food products. Therefore, extensive study of the epidemiology of this food pathogen in Egypt is warranted. Strict procedures should be developed to monitor, protect, and safely handle food products, particularly ready-to-eat foodstuffs that are usually consumed without heat treatment. HIGHLIGHTS
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Affiliation(s)
- Heba M Amin
- Department of Microbiology and Immunology, Faculty of Pharmacy, October University for Modern Sciences and Arts (MSA), 6th of October City, Giza, Egypt
| | - Mahmoud M Tawfick
- Department of Microbiology and Immunology, Faculty of Pharmacy (Boys), Al-Azhar University, Nasr City, Cairo, Egypt; and
- Department of Microbiology and Public Health, Faculty of Pharmacy, Heliopolis University, Cairo, Egypt
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Glasset B, Sperry M, Dervyn R, Herbin S, Brisabois A, Ramarao N. The cytotoxic potential of Bacillus cereus strains of various origins. Food Microbiol 2021; 98:103759. [PMID: 33875199 DOI: 10.1016/j.fm.2021.103759] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 01/10/2021] [Accepted: 01/29/2021] [Indexed: 12/21/2022]
Abstract
B. cereus is a human pathogen associated with food poisoning leading to gastrointestinal disorders, as well as local and severe systemic infections. The pathogenic spectrum of B. cereus ranges from strains used as probiotics in humans to lethal highly toxic strains. In this study, we gathered a collection of 100 strains representative of the pathological diversity of B. cereus in humans, and characterized these strains for their cytotoxic potential towards human cells. We analyzed the correlation between cytotoxicity to epithelial and macrophage cells and the combination of 10 genes suspected to play a role during B. cereus virulence. We highlight genetic differences among isolates and studied correlations between genetic signature, cytotoxicity and strain pathological status. We hope that our findings will improve our understanding of the pathogenicity of B. cereus, thereby making it possible to improve both clinical diagnosis and food safety.
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Affiliation(s)
- Benjamin Glasset
- Micalis Institute, INRAE, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France; Université Paris-Est, Anses, Laboratory for Food Safety, 94700, Maisons-Alfort, France
| | - Mylène Sperry
- Micalis Institute, INRAE, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Rozenn Dervyn
- Micalis Institute, INRAE, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Sabine Herbin
- Université Paris-Est, Anses, Laboratory for Food Safety, 94700, Maisons-Alfort, France
| | - Anne Brisabois
- Université Paris-Est, Anses, Laboratory for Food Safety, 94700, Maisons-Alfort, France
| | - Nalini Ramarao
- Micalis Institute, INRAE, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France.
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15
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Bonis M, Felten A, Pairaud S, Dijoux A, Maladen V, Mallet L, Radomski N, Duboisset A, Arar C, Sarda X, Vial G, Mistou MY, Firmesse O, Hennekinne JA, Herbin S. Comparative phenotypic, genotypic and genomic analyses of Bacillus thuringiensis associated with foodborne outbreaks in France. PLoS One 2021; 16:e0246885. [PMID: 33607651 PMCID: PMC7895547 DOI: 10.1371/journal.pone.0246885] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 01/28/2021] [Indexed: 11/18/2022] Open
Abstract
Bacillus thuringiensis (Bt) belongs to the Bacillus cereus (Bc) group, well known as an etiological agent of foodborne outbreaks (FBOs). Bt distinguishes itself from other Bc by its ability to synthesize insecticidal crystals. However, the search for these crystals is not routinely performed in food safety or clinical investigation, and the actual involvement of Bt in the occurrence of FBOs is not known. In the present study, we reveal that Bt was detected in the context of 49 FBOs declared in France between 2007 and 2017. In 19 of these FBOs, Bt was the only microorganism detected, making it the most likely causal agent. Searching for its putative origin of contamination, we noticed that more than 50% of Bt isolates were collected from dishes containing raw vegetables, in particular tomatoes (48%). Moreover, the genomic characterization of isolates showed that most FBO-associated Bt isolates exhibited a quantified genomic proximity to Bt strains, used as biopesticides, especially those from subspecies aizawai and kurstaki. Taken together, these results strengthen the hypothesis of an agricultural origin for the Bt contamination and call for further investigations on Bt pesticides.
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Affiliation(s)
- Mathilde Bonis
- Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Arnaud Felten
- Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Sylvie Pairaud
- Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Angélie Dijoux
- Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Véronique Maladen
- Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Ludovic Mallet
- Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Nicolas Radomski
- Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Arnaud Duboisset
- Regulated Products Assessment Department, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Chantal Arar
- Regulated Products Assessment Department, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Xavier Sarda
- Regulated Products Assessment Department, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Gaelle Vial
- Regulated Products Assessment Department, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Michel-Yves Mistou
- Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Olivier Firmesse
- Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
- * E-mail:
| | - Jacques-Antoine Hennekinne
- Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
| | - Sabine Herbin
- Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, Maisons-Alfort, France
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Bacillus cereus Induces Severe Infections in Preterm Neonates: Implication at the Hospital and Human Milk Bank Level. Toxins (Basel) 2021; 13:toxins13020123. [PMID: 33562185 PMCID: PMC7915446 DOI: 10.3390/toxins13020123] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/18/2021] [Accepted: 02/02/2021] [Indexed: 12/15/2022] Open
Abstract
Human breast milk (HBM) is a source of essential nutrients for infants and is particularly recommended for preterm neonates when their own mother’s milk is not available. It provides protection against infections and decreases necrotizing enterocolitis and cardiovascular diseases. Nevertheless, HBM spoilage can occur due to contamination by pathogens, and the risk of a shortage of HBM is very often present. B. cereus is the most frequent ubiquitous bacteria responsible for HBM being discarded. It can contaminate HBM at all stages, from its collect point to the storage and delivery. B. cereus can induce severe infection in newborns with very low birth weight, with sometimes fatal outcomes. Although the source of contamination is rarely identified, in some cases, HBM was suspected as a potential source. Even if the risk is low, as infection due to B. cereus in preterm infants should not be overlooked, human milk banks follow strict procedures to avoid contamination, to accurately identify remaining bacteria following pasteurization and to discard non-compliant milk samples. In this review, we present a literature overview of B. cereus infections reported in neonates and the suspected sources of contamination. We highlight the procedures followed by the human milk banks from the collection of the milk to its microbiological characterization in Europe. We also present improved detection and decontamination methods that might help to decrease the risk and to preserve the public’s confidence in this vital biological product for infants whose mothers cannot breastfeed.
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Adjidé CC, Léké A, Mullié C. Bacillus cereus contamination of pasteurized human milk donations: frequency, origin, seasonal distribution, molecular typing of strains and proposed corrective/preventive actions. J Matern Fetal Neonatal Med 2020; 35:1554-1561. [PMID: 32393084 DOI: 10.1080/14767058.2020.1763295] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Objectives: An increase in pasteurized human milk contamination with Bacillus cereus was witnessed in milk donated to the Amiens-Picardie Human Milk Bank over the 2017-2018 period. To better understand the origin of such an increase, this study aimed to describe the frequency of Bacillus cereus contamination in anonymous and personalized human milk donations of Amiens Human Milk Bank in 2018, compare the genetic profiles of Bacillus cereus strains found in pasteurized human milk and set up corrective/preventive actions to reduce Bacillus cereus contamination.Study design: A retrospective cohort study of human milk donated from January to December 2018 was set. Data on the microbiological quality of donated human milk and genetic profiles of Bacillus cereus strains isolated from pasteurized donated human milk and the environment were collected.Results: The overall noncompliance rate related to the microbiological quality in the 1585 batches of analyzed human milk donations was of 27.3%. Post-Holder pasteurization, rejection rates were significantly higher for anonymous donations as compared to personalized ones. Bacillus cereus was the main cause of noncompliance. Bacillus cereus contaminations could not be attributed to a single strain spreading through Amiens human milk bank and Amiens hospital environment as the genetic profiles of the collected strains were different. Corrective actions led to a decrease in the noncompliance rate due to Bacillus cereus (37.7-9.7%) post-Holder pasteurization.Conclusion: Bacillus cereus was the primary cause of rejection for pasteurized human milk donations over the investigated period. These contaminations did not originate from the spread of a single strain. A first round of corrective actions enabled a fair decrease in Bacillus cereus contaminations.
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Affiliation(s)
- Crespin C Adjidé
- Laboratoire Hygiène Risque Biologique & Environnement, Centre Hospitalier Universitaire Amiens-Picardie, Amiens, France
| | - André Léké
- Lactarium-Biberonnerie, Unité des soins intensifs de néonatologie et de médecine néonatale, Centre Hospitalier Universitaire Amiens-Picardie, Amiens, France
| | - Catherine Mullié
- Laboratoire Hygiène Risque Biologique & Environnement, Centre Hospitalier Universitaire Amiens-Picardie, Amiens, France.,Laboratoire AGIR UR UPJV 4294, UFR de Pharmacie, Université de Picardie Jules Verne, Amiens, France
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18
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Ramarao N, Tran SL, Marin M, Vidic J. Advanced Methods for Detection of Bacillus cereus and Its Pathogenic Factors. SENSORS (BASEL, SWITZERLAND) 2020; 20:E2667. [PMID: 32392794 PMCID: PMC7273213 DOI: 10.3390/s20092667] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/02/2020] [Accepted: 05/05/2020] [Indexed: 12/21/2022]
Abstract
Bacillus cereus is an opportunistic foodborne pathogen causing food intoxication and infectious diseases. Different toxins and pathogenic factors are responsible for diarrheal syndrome, like nonhemolytic enterotoxin Nhe, hemolytic enterotoxin Hbl, enterotoxin FM and cytotoxin K, while emetic syndrome is caused by the depsipeptide cereulide toxin. The traditional method of B. cereus detection is based on the bacterial culturing onto selective agars and cells enumeration. In addition, molecular and chemical methods are proposed for toxin gene profiling, toxin quantification and strain screening for defined virulence factors. Finally, some advanced biosensors such as phage-based, cell-based, immunosensors and DNA biosensors have been elaborated to enable affordable, sensitive, user-friendly and rapid detection of specific B. cereus strains. This review intends to both illustrate the state of the B. cereus diagnostic field and to highlight additional research that is still at the development level.
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Affiliation(s)
- Nalini Ramarao
- INRAE, AgroParisTech, Micalis Institute, Université Paris-Saclay, 78350 Jouy-en-Josas, France; (S.-L.T.); (M.M.)
| | | | | | - Jasmina Vidic
- INRAE, AgroParisTech, Micalis Institute, Université Paris-Saclay, 78350 Jouy-en-Josas, France; (S.-L.T.); (M.M.)
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19
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Bacillus cereus infection in neonates and the absence of evidence for the role of banked human milk: Case reports and literature review. Infect Control Hosp Epidemiol 2020; 40:787-793. [PMID: 31172903 DOI: 10.1017/ice.2019.110] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Banked human milk (BHM) has inherent infectious risks, even when pasteurized. Because of the ubiquity of Bacillus cereus in the environment and its ability to resist the Holder pasteurization process, there is a concern that BHM might lead to severe B. cereus infections. OBJECTIVE We reviewed observed and published cases to determine the potential causal role of BHM as the source of these infections. METHODS Two infants in the province of Québec (Canada) developed a B. cereus neonatal infection, and both had received BHM. We conducted bacteriological studies to compare clinical isolates and those found in these cases. RESULTS After extended culture of BHM retention lots, B. cereus was found to have been involved in batches related to the first case. However, molecular typing showed that the strain was different from the clinical isolate, therefore excluding BHM as the source of contamination. In the second case, a Brevibacillus spp was isolated, a species distinct from the clinical isolate. CONCLUSION Based on these cases and others reported in the literature, a causal link between B. cereus contaminated BHM and preterm neonatal infection has never been documented. Therefore, the risk that BHM can cause this infection remains theoretical. Given the widespread presence of B. cereus in the hospital environment and its capacity to resist standard cleaning procedures, it seems likely that airborne or direct or indirect contact are the main sources of most, if not all, cases of severe B. cereus neonatal infections, even in babies exposed to BHM.
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Abstract
The Bacillus cereus group includes several Bacillus species with closely related phylogeny. The most well-studied members of the group, B. anthracis, B. cereus, and B. thuringiensis, are known for their pathogenic potential. Here, we present the historical rationale for speciation and discuss shared and unique features of these bacteria. Aspects of cell morphology and physiology, and genome sequence similarity and gene synteny support close evolutionary relationships for these three species. For many strains, distinct differences in virulence factor synthesis provide facile means for species assignment. B. anthracis is the causative agent of anthrax. Some B. cereus strains are commonly recognized as food poisoning agents, but strains can also cause localized wound and eye infections as well as systemic disease. Certain B. thuringiensis strains are entomopathogens and have been commercialized for use as biopesticides, while some strains have been reported to cause infection in immunocompromised individuals. In this article we compare and contrast B. anthracis, B. cereus, and B. thuringiensis, including ecology, cell structure and development, virulence attributes, gene regulation and genetic exchange systems, and experimental models of disease.
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21
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Virulence potentials of Bacillus strains recovered from edible snails and survival during culinary preparation. Food Control 2020. [DOI: 10.1016/j.foodcont.2019.106834] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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A Cluster of Bacillus cereus Infections in the Neonatal Intensive Care Unit: Epidemiologic and Whole-genome Sequencing Analysis. Pediatr Infect Dis J 2019; 38:e301-e306. [PMID: 31626047 DOI: 10.1097/inf.0000000000002441] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Bacillus cereus isolates causing an outbreak in the neonatal intensive care unit were investigated using whole-genome sequencing. The outbreak coincided with construction work performed adjacent to the neonatal intensive care unit and ceased after strict sealing of the construction area. We found the outbreak to be polyclonal, however, the clonality did not correlate with the virulence in vivo. Genotypically similar isolates were associated with both lethal/severe infection and colonization/environmental contamination. Environmental bacterial load may be a major determinant of infection, especially in high-risk patients. Clinicians should be alert to unusual increase in B. cereus isolations from clinical cultures to facilitate early recognition and investigations of Bacillus outbreaks and pseudo-outbreaks. The integration of genomics into the classical infectious disease work can augment our understanding of pathogen transmission and virulence, and can rapidly assist our response to unusual disease trends.
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Multifaceted toxin profile of Bacillus probiotic in newly isolated Bacillus spp. from soil rhizosphere. Biologia (Bratisl) 2019. [DOI: 10.2478/s11756-019-00357-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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The PlyB Endolysin of Bacteriophage vB_BanS_Bcp1 Exhibits Broad-Spectrum Bactericidal Activity against Bacillus cereus Sensu Lato Isolates. Appl Environ Microbiol 2019; 85:AEM.00003-19. [PMID: 30850428 DOI: 10.1128/aem.00003-19] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Accepted: 02/27/2019] [Indexed: 12/15/2022] Open
Abstract
Lytic bacteriophages (or phages) drive bacterial mortality by elaborating exquisite abilities to bind, breach, and destroy bacterial cell membranes and subjugate critical bacterial cell functions. These antimicrobial activities make phages ideal candidates to serve as, or provide sources of, biological control measures for bacterial pathogens. In this study, we isolated the Myoviridae phage vB_BanS_Bcp1 (here referred to as Bcp1) from landfill soil, using a Bacillus anthracis host. The antimicrobial activities of both Bcp1 and its encoded endolysin, PlyB, were examined across different B. cereus sensu lato group species, including B. cereus sensu stricto, Bacillus thuringiensis, and Bacillus anthracis, with pathogenic potential in humans and multiple different uses in biotechnological applications. The Bcp1 phage infected only a subset (11 to 66%) of each B. cereus sensu lato species group tested. In contrast, functional analysis of purified PlyB revealed a potent bacteriolytic activity against all B. cereus sensu lato isolates tested (n = 79). PlyB was, furthermore, active across broad temperature, pH, and salt ranges, refractory to the development of resistance, bactericidal as a single agent, and synergistic with a second endolysin, PlyG. To confirm the potential for PlyB as an antimicrobial agent, we demonstrated the efficacy of a single intravenous treatment with PlyB alone or combination with PlyG in a murine model of lethal B. anthracis infection. Overall, our findings show exciting potential for the Bcp1 bacteriophage and the PlyB endolysin as potential new additions to the antimicrobial armamentarium.IMPORTANCE Organisms of the Bacillus cereus sensu lato lineage are ubiquitous in the environment and are responsible for toxin-mediated infections ranging from severe food poisoning (B. cereus sensu stricto) to anthrax (Bacillus anthracis). The increasing incidence of many of these infections, combined with the specter of antibiotic resistance, has created a need for novel antimicrobials with potent activity, including bacteriophages (or phages) and phage-encoded products (i.e., endolysins). In this study, we describe a broadly infective phage, Bcp1, and its encoded endolysin, PlyB, which exhibited a rapidly bacteriolytic effect against all B. cereus sensu lato isolates tested with no evidence of evolving resistance. Importantly, PlyB was highly efficacious in a mouse model of lethal bacteremia with B. anthracis Both the Bcp1 phage and the PlyB endolysin represent novel mechanisms of action compared to antibiotics, with potential applications to address the evolving problem of antimicrobial resistance.
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Carroll LM, Wiedmann M, Mukherjee M, Nicholas DC, Mingle LA, Dumas NB, Cole JA, Kovac J. Characterization of Emetic and Diarrheal Bacillus cereus Strains From a 2016 Foodborne Outbreak Using Whole-Genome Sequencing: Addressing the Microbiological, Epidemiological, and Bioinformatic Challenges. Front Microbiol 2019; 10:144. [PMID: 30809204 PMCID: PMC6379260 DOI: 10.3389/fmicb.2019.00144] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 01/21/2019] [Indexed: 12/21/2022] Open
Abstract
The Bacillus cereus group comprises multiple species capable of causing emetic or diarrheal foodborne illness. Despite being responsible for tens of thousands of illnesses each year in the U.S. alone, whole-genome sequencing (WGS) is not yet routinely employed to characterize B. cereus group isolates from foodborne outbreaks. Here, we describe the first WGS-based characterization of isolates linked to an outbreak caused by members of the B. cereus group. In conjunction with a 2016 outbreak traced to a supplier of refried beans served by a fast food restaurant chain in upstate New York, a total of 33 B. cereus group isolates were obtained from human cases (n = 7) and food samples (n = 26). Emetic (n = 30) and diarrheal (n = 3) isolates were most closely related to B. paranthracis (group III) and B. cereus sensu stricto (group IV), respectively. WGS indicated that the 30 emetic isolates (24 and 6 from food and humans, respectively) were closely related and formed a well-supported clade distinct from publicly available emetic group III genomes with an identical sequence type (ST 26). The 30 emetic group III isolates from this outbreak differed from each other by a mean of 8.3 to 11.9 core single nucleotide polymorphisms (SNPs), while differing from publicly available emetic group III ST 26 B. cereus group genomes by a mean of 301.7-528.0 core SNPs, depending on the SNP calling methodology used. Using a WST-1 cell proliferation assay, the strains isolated from this outbreak had only mild detrimental effects on HeLa cell metabolic activity compared to reference diarrheal strain B. cereus ATCC 14579. We hypothesize that the outbreak was a single source outbreak caused by emetic group III B. cereus belonging to the B. paranthracis species, although food samples were not tested for presence of the emetic toxin cereulide. In addition to showcasing how WGS can be used to characterize B. cereus group strains linked to a foodborne outbreak, we also discuss potential microbiological and epidemiological challenges presented by B. cereus group outbreaks, and we offer recommendations for analyzing WGS data from the isolates associated with them.
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Affiliation(s)
- Laura M. Carroll
- Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Martin Wiedmann
- Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Manjari Mukherjee
- Department of Food Science, The Pennsylvania State University, University Park, PA, United States
| | - David C. Nicholas
- New York State Department of Health, Corning Tower, Empire State Plaza, Albany, NY, United States
| | - Lisa A. Mingle
- New York State Department of Health, Wadsworth Center, Albany, NY, United States
| | - Nellie B. Dumas
- New York State Department of Health, Wadsworth Center, Albany, NY, United States
| | - Jocelyn A. Cole
- New York State Department of Health, Wadsworth Center, Albany, NY, United States
| | - Jasna Kovac
- Department of Food Science, The Pennsylvania State University, University Park, PA, United States
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Banked Human Milk and Quantitative Risk Assessment of Bacillus cereus Infection in Premature Infants: A Simulation Study. CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY 2019; 2019:6348281. [PMID: 30863469 PMCID: PMC6378033 DOI: 10.1155/2019/6348281] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 12/31/2018] [Indexed: 11/17/2022]
Abstract
Background Banked human milk (BHM) offers potential health benefits to premature babies. BHM is pasteurized to mitigate infectious risks, but pasteurization is ineffective against sporulating bacteria such as Bacillus cereus. Sepsis related to Bacillus cereus in premature infants is severe and can often be fatal. Even if a causal link has never been established, BHM has been suggested as a potential source of infection in premature infants. Objective Our aim was to estimate the potential risk of Bacillus cereus infection in preterm infants caused by the ingestion of contaminated pasteurized BHM using different post-pasteurization release criteria (i.e., 9 sampling of 100 microliters versus the HMBANA guideline of 1 sampling of 100 microliters per pool). Methods In the absence of scientific evidence regarding the risk of Bacillus cereus infection by the ingestion of BHM in premature infants, risk assessment using Monte Carlo simulation with the exponential dose-response model was performed. Three scenarios of infectious risk (annual incidence rate of 0.01%, 0.13%, and 0.2%) with 18 variations of the B. cereus virulent dose (from 0.5 CFU/ml to 200 CFU/ml) were simulated. Results The mean risk differential between the two methods of post-pasteurization bacteriological control for realistic infectious doses of 30 to 200 CFU/ml ranges from 0.036 to 0.0054, 0.47 to 0.070, and 0.72 to 0.11 per million servings, for each of the three scenarios. Conclusion Simulation highlights the very small risk of Bacillus cereus infection following the ingestion of pasteurized BHM, even in the worst case scenarios, and suggests that a 100-microliter sample for post-pasteurization culture is sufficient.
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Identification and Containment of a Cluster of Two Bacillus cereus Infections in a Neonatal Intensive Care Unit. CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY 2019; 2019:1506583. [PMID: 30805067 PMCID: PMC6360598 DOI: 10.1155/2019/1506583] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 01/02/2019] [Indexed: 11/18/2022]
Abstract
We report a cluster of invasive Bacillus cereus infections in a neonatal intensive care unit. We describe the clinical course of two infected patients, one of whom died of severe pneumonia after successfully being weaned from ECMO. Environmental analyses failed to yield a common source. Molecular characterization confirmed the homogeneity of both isolates. Rigorous hygiene control and adequate therapy enabled the containment of the cluster.
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Picaud JC, Buffin R, Gremmo‐Feger G, Rigo J, Putet G, Casper C. Review concludes that specific recommendations are needed to harmonise the provision of fresh mother's milk to their preterm infants. Acta Paediatr 2018; 107:1145-1155. [PMID: 29412475 PMCID: PMC6032854 DOI: 10.1111/apa.14259] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Revised: 01/02/2018] [Accepted: 01/30/2018] [Indexed: 01/27/2023]
Abstract
AIM There are no specific recommendations for using a mother's fresh milk for her preterm infant. We reviewed the available evidence on its collection, storage and administration. METHODS The working group of the French Neonatal Society on fresh human milk use in preterm infants searched the MEDLINE database and Cochrane Library up to June 2017 for papers published in English or French. They specifically analysed 282 papers providing information on prospective, retrospective and clinical studies and examined guidelines from various countries. RESULTS The review concluded that fresh mother's own milk should be favoured in accordance with the latest recommendations. However, it must be carried out under stringent conditions so that the expected benefits are not offset by risks related to different practices. The working group has summarised the best conditions for feeding preterm infants with human milk, balancing high nutritional and immunological quality with adequate virological and bacteriological safety. Professionals must provide parents with the necessary conditions to establish breastfeeding, together with specific and strong support. CONCLUSION Based on their review, the working group has made specific recommendations for using fresh mother's own milk under careful conditions, so that the expected benefits are not offset by risks related to practices.
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Affiliation(s)
- JC Picaud
- Neonatal UnitHôpital de la Croix RousseHospices Civils de LyonLyonFrance
- Faculté de médecine Lyon‐Sud Charles MérieuxUniversité Claude Bernard Lyon 1VilleurbanneFrance
| | - R Buffin
- Neonatal UnitHôpital de la Croix RousseHospices Civils de LyonLyonFrance
| | - G Gremmo‐Feger
- Neonatal UnitPôle de la Femme, de la Mère et de l'EnfantCHU BrestBrestFrance
| | - J Rigo
- Neonatal UnitChU Liège Hopital de la CitadelleUniversité de LiègeLiègeBelgium
| | - G Putet
- Neonatal UnitHôpital de la Croix RousseHospices Civils de LyonLyonFrance
| | - C Casper
- Neonatal UnitPaul Sabatier UniversityToulouseFrance
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Haydar A, Tran SL, Guillemet E, Darrigo C, Perchat S, Lereclus D, Coquet L, Jouenne T, Ramarao N. InhA1-Mediated Cleavage of the Metalloprotease NprA Allows Bacillus cereus to Escape From Macrophages. Front Microbiol 2018; 9:1063. [PMID: 29875760 PMCID: PMC5974196 DOI: 10.3389/fmicb.2018.01063] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 05/04/2018] [Indexed: 12/20/2022] Open
Abstract
Bacillus cereus is a Gram-positive spore-forming bacterium causing food poisoning and serious opportunistic infections. These infections are characterized by bacterial accumulation in the host despite the induction of inflammation. To circumvent inflammation, bacteria must resist the bactericidal activity of professional phagocytes, which constitute a first line of host defense against pathogens. Interactions between phagocytic cells and B. cereus are still poorly characterized and the mechanism of resistance to the host immune system is not known yet. We have previously shown that the spores are phagocytosed by macrophages but survive and escape from these cells. The metalloprotease InhA1 is a key effector involved in these processes. inhA1-deficient spores are retained intracellularly, in contrast to the wild type strain spores. NprA is also a B. cereus metalloprotease able to cleave tissue components such as fibronectin, laminin, and collagen. Here, we show that NprA, concomitantly secreted with InhA1 in the B. cereus secretome, is essential to promote bacterial escape from macrophages. We show that InhA1 cleaves NprA at specific sites. This cleavage allows liberation of the mature form of the NprA protein in the supernatant of the wild type strain. This mature form of NprA is actually the principal effector allowing bacterial escape from host macrophages.
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Affiliation(s)
- Abbass Haydar
- INRA, Micalis Institute, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Seav-Ly Tran
- INRA, Micalis Institute, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Elisabeth Guillemet
- INRA, Micalis Institute, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Claire Darrigo
- INRA, Micalis Institute, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Stéphane Perchat
- INRA, Micalis Institute, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Didier Lereclus
- INRA, Micalis Institute, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Laurent Coquet
- CNRS, UMR 6270, Normandy University, UNIROUEN, Plate-forme PISSARO, Mont-Saint-Aignan, France
| | - Thierry Jouenne
- CNRS, UMR 6270, Normandy University, UNIROUEN, Plate-forme PISSARO, Mont-Saint-Aignan, France
| | - Nalini Ramarao
- INRA, Micalis Institute, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
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Glasset B, Herbin S, Granier SA, Cavalié L, Lafeuille E, Guérin C, Ruimy R, Casagrande-Magne F, Levast M, Chautemps N, Decousser JW, Belotti L, Pelloux I, Robert J, Brisabois A, Ramarao N. Bacillus cereus, a serious cause of nosocomial infections: Epidemiologic and genetic survey. PLoS One 2018; 13:e0194346. [PMID: 29791442 PMCID: PMC5966241 DOI: 10.1371/journal.pone.0194346] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 03/01/2018] [Indexed: 11/19/2022] Open
Abstract
Bacillus cereus is the 2nd most frequent bacterial agent responsible for food-borne outbreaks in France and the 3rd in Europe. In addition, local and systemic infections have been reported, mainly describing individual cases or single hospital setting. The real incidence of such infection is unknown and information on genetic and phenotypic characteristics of the incriminated strains is generally scarce. We performed an extensive study of B. cereus strains isolated from patients and hospital environments from nine hospitals during a 5-year study, giving an overview of the consequences, sources and pathogenic patterns of B. cereus clinical infections. We demonstrated the occurrence of several hospital-cross-contaminations. Identical B. cereus strains were recovered from different patients and hospital environments for up to 2 years. We also clearly revealed the occurrence of inter hospital contaminations by the same strain. These cases represent the first documented events of nosocomial epidemy by B. cereus responsible for intra and inter hospitals contaminations. Indeed, contamination of different patients with the same strain of B. cereus was so far never shown. In addition, we propose a scheme for the characterization of B. cereus based on biochemical properties and genetic identification and highlight that main genetic signatures may carry a high pathogenic potential. Moreover, the characterization of antibiotic resistance shows an acquired resistance phenotype for rifampicin. This may provide indication to adjust the antibiotic treatment and care of patients.
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Affiliation(s)
- Benjamin Glasset
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
- Université Paris-Est, Anses, Laboratory for Food Safety, Maisons-Alfort, France
| | - Sabine Herbin
- Université Paris-Est, Anses, Laboratory for Food Safety, Maisons-Alfort, France
| | - Sophie A. Granier
- Université Paris-Est, Anses, Laboratory for Food Safety, Maisons-Alfort, France
| | - Laurent Cavalié
- CHU Toulouse, Service de Bactériologie-Hygiène, IRSD, Université de Toulouse, INSERM, INRA, ENVT, UPS, Toulouse, France
| | - Emilie Lafeuille
- Sorbonne Universités, UPMC Univ Paris 06, Inserm, U1135, Centre d’Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
- Laboratoire de Bactériologie-Hygiène, Hôpitaux Universitaires Pitié-Salpêtrière-Charles Foix, APHP, Paris, France
| | - Cyprien Guérin
- MaiAGE, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
| | - Raymond Ruimy
- CHU Nice, Laboratoire de bactériologie, Nice, France
| | | | - Marion Levast
- Hôpital de Chambéry, Laboratoire de Biologie Médicale, Chambéry, France
| | | | - Jean-Winoc Decousser
- Hôpitaux Universitaires Paris-Sud Antoine Béclère, Laboratoire Hygiène, Clamart, France
| | - Laure Belotti
- CHU Strasbourg, Laboratoire d’hygiène hospitalière, Strasbourg, France
| | | | - Jerôme Robert
- Sorbonne Universités, UPMC Univ Paris 06, Inserm, U1135, Centre d’Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
- Laboratoire de Bactériologie-Hygiène, Hôpitaux Universitaires Pitié-Salpêtrière-Charles Foix, APHP, Paris, France
| | - Anne Brisabois
- Université Paris-Est, Anses, Laboratory for Food Safety, Maisons-Alfort, France
| | - Nalini Ramarao
- Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France
- * E-mail:
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Escuder-Vieco D, Espinosa-Martos I, Rodríguez JM, Corzo N, Montilla A, Siegfried P, Pallás-Alonso CR, Fernández L. High-Temperature Short-Time Pasteurization System for Donor Milk in a Human Milk Bank Setting. Front Microbiol 2018; 9:926. [PMID: 29867837 PMCID: PMC5958646 DOI: 10.3389/fmicb.2018.00926] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 04/20/2018] [Indexed: 12/05/2022] Open
Abstract
Donor milk is the best alternative for the feeding of preterm newborns when mother's own milk is unavailable. For safety reasons, it is usually pasteurized by the Holder method (62.5°C for 30 min). Holder pasteurization results in a microbiological safe product but impairs the activity of many biologically active compounds such as immunoglobulins, enzymes, cytokines, growth factors, hormones or oxidative stress markers. High-temperature short-time (HTST) pasteurization has been proposed as an alternative for a better preservation of some of the biological components of human milk although, at present, there is no equipment available to perform this treatment under the current conditions of a human milk bank. In this work, the specific needs of a human milk bank setting were considered to design an HTST equipment for the continuous and adaptable (time-temperature combination) processing of donor milk. Microbiological quality, activity of indicator enzymes and indices for thermal damage of milk were evaluated before and after HTST treatment of 14 batches of donor milk using different temperature and time combinations and compared to the results obtained after Holder pasteurization. The HTST system has accurate and simple operation, allows the pasteurization of variable amounts of donor milk and reduces processing time and labor force. HTST processing at 72°C for, at least, 10 s efficiently destroyed all vegetative forms of microorganisms present initially in raw donor milk although sporulated Bacillus sp. survived this treatment. Alkaline phosphatase was completely destroyed after HTST processing at 72 and 75°C, but γ-glutamil transpeptidase showed higher thermoresistance. Furosine concentrations in HTST-treated donor milk were lower than after Holder pasteurization and lactulose content for HTST-treated donor milk was below the detection limit of analytical method (10 mg/L). In conclusion, processing of donor milk at 72°C for at least 10 s in this HTST system allows to achieve the microbiological safety objectives established in the milk bank while having a lower impact regarding the heat damage of the milk.
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Affiliation(s)
- Diana Escuder-Vieco
- Banco Regional de Leche Materna, Hospital Universitario 12 de Octubre, Instituto de Investigación i+12, Madrid, Spain
| | | | - Juan M Rodríguez
- Departamento de Nutrición, Bromatología y Tecnología de los Alimentos, Universidad Complutense de Madrid, Madrid, Spain
| | - Nieves Corzo
- Departamento de Bioactividad y Análisis de Alimentos, Instituto de Investigación en Ciencias de la Alimentación, CIAL (CSIC-UAM), Madrid, Spain
| | - Antonia Montilla
- Departamento de Bioactividad y Análisis de Alimentos, Instituto de Investigación en Ciencias de la Alimentación, CIAL (CSIC-UAM), Madrid, Spain
| | | | - Carmen R Pallás-Alonso
- Banco Regional de Leche Materna, Hospital Universitario 12 de Octubre, Instituto de Investigación i+12, Madrid, Spain.,Servicio de Neonatología, Hospital Universitario 12 de Octubre, Instituto de Investigación i+12, Universidad Complutense de Madrid, Madrid, Spain
| | - Leónides Fernández
- Departamento de Nutrición, Bromatología y Tecnología de los Alimentos, Universidad Complutense de Madrid, Madrid, Spain
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Recent actuality about Bacillus cereus and human milk bank: a new sensitive method for microbiological analysis of pasteurized milk. Eur J Clin Microbiol Infect Dis 2018; 37:1297-1303. [PMID: 29725957 DOI: 10.1007/s10096-018-3249-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 03/28/2018] [Indexed: 10/17/2022]
Abstract
Three cases of Bacillus cereus infection or colonization occurred in the same region in France, and milk from the milk bank was suspected as a possible common source of contamination. All Batches delivered to the three cases complied with the requirements of the bacteriological reference method recommended by good practices guidelines. Still, a retrospective analysis with a more sensitive method showed one batch to contain B. cereus, however straincomparison revealed no epidemiological link betweenisolates from patients and those from the milk. Consequently, in accordance with the precautionary principle, we developed a new sensitive method for the screening of pasteurized milk for pathogenic bacteria. From January 1 to August 31, 2017, 2526 samples of pasteurized milk were prospectively included in the study. We showed that a 20 mL sample of pasteurized milk incubated for 18 h at 37 °C under aerobic conditions was favoring the detection of B. Cereus. The nonconformity rate was 6.3% for the reference method and 12.6% for the improved method (p < 0.0001). Nonconformity was due to the presence of B. cereus in 88.5% of cases for the improved method and 53% of cases for the reference method (p < 0.0001). Thus our new method is improves the microbiological safety of the product distributed and only moderately increases the rate of bacteriological nonconformity .
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