1
|
Andrews JR, Yu AT, Saha S, Shakya J, Aiemjoy K, Horng L, Qamar F, Garrett D, Baker S, Saha S, Luby SP. Environmental Surveillance as a Tool for Identifying High-risk Settings for Typhoid Transmission. Clin Infect Dis 2021; 71:S71-S78. [PMID: 32725227 PMCID: PMC7446943 DOI: 10.1093/cid/ciaa513] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Enteric fever remains a major cause of morbidity in developing countries with poor sanitation conditions that enable fecal contamination of water distribution systems. Historical evidence has shown that contamination of water systems used for household consumption or agriculture are key transmission routes for Salmonella Typhi and Salmonella Paratyphi A. The World Health Organization now recommends that typhoid conjugate vaccines (TCV) be used in settings with high typhoid incidence; consequently, governments face a challenge regarding how to prioritize typhoid against other emerging diseases. A key issue is the lack of typhoid burden data in many low- and middle-income countries where TCV could be deployed. Here we present an argument for utilizing environmental sampling for the surveillance of enteric fever organisms to provide data on community-level typhoid risk. Such an approach could complement traditional blood culture-based surveillance or even replace it in settings where population-based clinical surveillance is not feasible. We review historical studies characterizing the transmission of enteric fever organisms through sewage and water, discuss recent advances in the molecular detection of typhoidal Salmonella in the environment, and outline challenges and knowledge gaps that need to be addressed to establish environmental sampling as a tool for generating actionable data that can inform public health responses to enteric fever.
Collapse
Affiliation(s)
- Jason R Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - Alexander T Yu
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - Senjuti Saha
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Jivan Shakya
- Dhulikhel Hospital, Kathmandu University Hospital, Dhulikhel, Nepal
| | - Kristen Aiemjoy
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - Lily Horng
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - Farah Qamar
- Department of Pediatrics and Child Health, Aga Khan University Hospital Karachi, Karachi, Pakistan
| | | | - Stephen Baker
- Department of Medicine, Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID) University of Cambridge, Cambridge, United Kingdom
| | - Samir Saha
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Stephen P Luby
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA
| |
Collapse
|
2
|
Reviving the "Moore Swab": a Classic Environmental Surveillance Tool Involving Filtration of Flowing Surface Water and Sewage Water To Recover Typhoidal Salmonella Bacteria. Appl Environ Microbiol 2020; 86:AEM.00060-20. [PMID: 32332133 PMCID: PMC7301852 DOI: 10.1128/aem.00060-20] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The “Moore swab” is a classic environmental surveillance tool whereby a gauze pad tied with string is suspended in flowing water or wastewater contaminated with human feces and harboring enteric pathogens that pose a human health threat. In contrast to single volume “grab” samples, Moore swabs act as continuous filters to “trap” microorganisms, which are subsequently isolated and confirmed using appropriate laboratory methods. Continuous filtration is valuable for the isolation of transiently present pathogens such as human-restricted Salmonella enterica serovars Typhi and Paratyphi A and B. The “Moore swab” is a classic environmental surveillance tool whereby a gauze pad tied with string is suspended in flowing water or wastewater contaminated with human feces and harboring enteric pathogens that pose a human health threat. In contrast to single volume “grab” samples, Moore swabs act as continuous filters to “trap” microorganisms, which are subsequently isolated and confirmed using appropriate laboratory methods. Continuous filtration is valuable for the isolation of transiently present pathogens such as human-restricted Salmonella enterica serovars Typhi and Paratyphi A and B. The technique was first proposed (1948) to trace Salmonella Paratyphi B systematically through sewers to pinpoint the residence of a chronic carrier responsible for sporadic outbreaks of paratyphoid fever. From 1948 to 1986, Moore swabs proved instrumental to identify long-term human reservoirs (chronic carriers) and long-cycle environmental transmission pathways of S. Typhi and Paratyphi, for example, to decipher endemic transmission in Santiago, Chile, during the 1980s. Despite limitations such as intermittent shedding of typhoidal Salmonella by humans and the effects of dilution, S. Typhi and S. Paratyphi have been recovered from sewers, surface waters, irrigation canals, storm drains, flush toilets, and septic tanks by using Moore swabs. Driven by the emergence of multiple antibiotic-resistant S. Typhi and S. Paratyphi A strains that limit treatment options, several countries are embarking on accelerated typhoid control programs using vaccines and environmental interventions. Moore swabs, which are regaining appreciation as important components of the public health/environmental microbiology toolbox, can enhance environmental surveillance for typhoidal Salmonella, thereby contributing to the control of typhoid fever.
Collapse
|
3
|
Viable-but-Nonculturable Listeria monocytogenes and Salmonella enterica Serovar Thompson Induced by Chlorine Stress Remain Infectious. mBio 2018; 9:mBio.00540-18. [PMID: 29666286 PMCID: PMC5904417 DOI: 10.1128/mbio.00540-18] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The microbiological safety of fresh produce is monitored almost exclusively by culture-based detection methods. However, bacterial food-borne pathogens are known to enter a viable-but-nonculturable (VBNC) state in response to environmental stresses such as chlorine, which is commonly used for fresh produce decontamination. Here, complete VBNC induction of green fluorescent protein-tagged Listeria monocytogenes and Salmonella enterica serovar Thompson was achieved by exposure to 12 and 3 ppm chlorine, respectively. The pathogens were subjected to chlorine washing following incubation on spinach leaves. Culture data revealed that total viable L. monocytogenes and Salmonella Thompson populations became VBNC by 50 and 100 ppm chlorine, respectively, while enumeration by direct viable counting found that chlorine caused a <1-log reduction in viability. The pathogenicity of chlorine-induced VBNC L. monocytogenes and Salmonella Thompson was assessed by using Caenorhabditis elegans Ingestion of VBNC pathogens by C. elegans resulted in a significant life span reduction (P = 0.0064 and P < 0.0001), and no significant difference between the life span reductions caused by the VBNC and culturable L. monocytogenes treatments was observed. L. monocytogenes was visualized beyond the nematode intestinal lumen, indicating resuscitation and cell invasion. These data emphasize the risk that VBNC food-borne pathogens could pose to public health should they continue to go undetected.IMPORTANCE Many bacteria are known to enter a viable-but-nonculturable (VBNC) state in response to environmental stresses. VBNC cells cannot be detected by standard laboratory culture techniques, presenting a problem for the food industry, which uses these techniques to detect pathogen contaminants. This study found that chlorine, a sanitizer commonly used for fresh produce, induces a VBNC state in the food-borne pathogens Listeria monocytogenes and Salmonella enterica It was also found that chlorine is ineffective at killing total populations of the pathogens. A life span reduction was observed in Caenorhabditis elegans that ingested these VBNC pathogens, with VBNC L. monocytogenes as infectious as its culturable counterpart. These data show that VBNC food-borne pathogens can both be generated and avoid detection by industrial practices while potentially retaining the ability to cause disease.
Collapse
|
4
|
Park S, Navratil S, Gregory A, Bauer A, Srinath I, Szonyi B, Nightingale K, Anciso J, Jun M, Han D, Lawhon S, Ivanek R. Multifactorial effects of ambient temperature, precipitation, farm management, and environmental factors determine the level of generic Escherichia coli contamination on preharvested spinach. Appl Environ Microbiol 2015; 81:2635-50. [PMID: 25636850 PMCID: PMC4357951 DOI: 10.1128/aem.03793-14] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 01/27/2015] [Indexed: 11/20/2022] Open
Abstract
A repeated cross-sectional study was conducted to identify farm management, environment, weather, and landscape factors that predict the count of generic Escherichia coli on spinach at the preharvest level. E. coli was enumerated for 955 spinach samples collected on 12 farms in Texas and Colorado between 2010 and 2012. Farm management and environmental characteristics were surveyed using a questionnaire. Weather and landscape data were obtained from National Resources Information databases. A two-part mixed-effect negative binomial hurdle model, consisting of a logistic and zero-truncated negative binomial part with farm and date as random effects, was used to identify factors affecting E. coli counts on spinach. Results indicated that the odds of a contamination event (non-zero versus zero counts) vary by state (odds ratio [OR] = 108.1). Odds of contamination decreased with implementation of hygiene practices (OR = 0.06) and increased with an increasing average precipitation amount (mm) in the past 29 days (OR = 3.5) and the application of manure (OR = 52.2). On contaminated spinach, E. coli counts increased with the average precipitation amount over the past 29 days. The relationship between E. coli count and the average maximum daily temperature over the 9 days prior to sampling followed a quadratic function with the highest bacterial count at around 24°C. These findings indicate that the odds of a contamination event in spinach are determined by farm management, environment, and weather factors. However, once the contamination event has occurred, the count of E. coli on spinach is determined by weather only.
Collapse
Affiliation(s)
- Sangshin Park
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA Center for International Health Research, Rhode Island Hospital, The Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA
| | - Sarah Navratil
- Department of Animal Sciences, Colorado State University, Fort Collins, Colorado, USA Department of Animal and Food Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Ashley Gregory
- Department of Horticultural Sciences, Texas A&M AgriLife Extension Service, Weslaco, Texas, USA
| | - Arin Bauer
- Department of Horticultural Sciences, Texas A&M AgriLife Extension Service, Weslaco, Texas, USA
| | - Indumathi Srinath
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA Tarleton State University, Stephenville, Texas, USA
| | - Barbara Szonyi
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Kendra Nightingale
- Department of Animal Sciences, Colorado State University, Fort Collins, Colorado, USA Department of Animal and Food Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Juan Anciso
- Department of Horticultural Sciences, Texas A&M AgriLife Extension Service, Weslaco, Texas, USA
| | - Mikyoung Jun
- Department of Statistics, Texas A&M University, College Station, Texas, USA
| | - Daikwon Han
- Department of Epidemiology and Biostatistics, School of Public Health, Texas A&M Health Science Center, College Station, Texas, USA
| | - Sara Lawhon
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Renata Ivanek
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| |
Collapse
|
5
|
Habimana O, Nesse L, Møretrø T, Berg K, Heir E, Vestby L, Langsrud S. The persistence of Salmonella
following desiccation under feed processing environmental conditions: a subject of relevance. Lett Appl Microbiol 2014; 59:464-70. [DOI: 10.1111/lam.12308] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 07/15/2014] [Accepted: 07/15/2014] [Indexed: 10/25/2022]
Affiliation(s)
- O. Habimana
- Nofima AS; Norwegian Institute of Food, Fishery and Aquaculture; Ås Norway
| | - L.L. Nesse
- Norwegian Veterinary Institute; Oslo Norway
| | - T. Møretrø
- Nofima AS; Norwegian Institute of Food, Fishery and Aquaculture; Ås Norway
| | - K. Berg
- Norwegian Veterinary Institute; Oslo Norway
| | - E. Heir
- Nofima AS; Norwegian Institute of Food, Fishery and Aquaculture; Ås Norway
| | | | - S. Langsrud
- Nofima AS; Norwegian Institute of Food, Fishery and Aquaculture; Ås Norway
| |
Collapse
|
6
|
Saeki EK, Alves J, Bonfante RC, Hirooka EY, de Oliveira TCRM. Multiplex PCR (mPCR) for the Detection of Salmonella
spp. and the Differentiation of the Typhimurium and Enteritidis Serovars in Chicken Meat. J Food Saf 2012. [DOI: 10.1111/jfs.12019] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Erika Kushikawa Saeki
- Department of Food Science and Technology; State University of Londrina; Rodovia Celso Garcia Cid, PR 445, Km 380, Campus Universitário, Caixa Postal 6001 CEP: 86051-990 Londrina Paraná Brasil
| | - Juliane Alves
- Department of Food Science and Technology; State University of Londrina; Rodovia Celso Garcia Cid, PR 445, Km 380, Campus Universitário, Caixa Postal 6001 CEP: 86051-990 Londrina Paraná Brasil
| | - Raissa Curti Bonfante
- Department of Food Science and Technology; State University of Londrina; Rodovia Celso Garcia Cid, PR 445, Km 380, Campus Universitário, Caixa Postal 6001 CEP: 86051-990 Londrina Paraná Brasil
| | - Elisa Yoko Hirooka
- Department of Food Science and Technology; State University of Londrina; Rodovia Celso Garcia Cid, PR 445, Km 380, Campus Universitário, Caixa Postal 6001 CEP: 86051-990 Londrina Paraná Brasil
| | - Tereza Cristina Rocha Moreira de Oliveira
- Department of Food Science and Technology; State University of Londrina; Rodovia Celso Garcia Cid, PR 445, Km 380, Campus Universitário, Caixa Postal 6001 CEP: 86051-990 Londrina Paraná Brasil
| |
Collapse
|
7
|
Waldner LL, MacKenzie KD, Köster W, White AP. From Exit to Entry: Long-term Survival and Transmission of Salmonella. Pathogens 2012; 1:128-55. [PMID: 25436767 PMCID: PMC4235688 DOI: 10.3390/pathogens1020128] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 09/15/2012] [Accepted: 10/10/2012] [Indexed: 02/01/2023] Open
Abstract
Salmonella spp. are a leading cause of human infectious disease worldwide and pose a serious health concern. While we have an improving understanding of pathogenesis and the host-pathogen interactions underlying the infection process, comparatively little is known about the survival of pathogenic Salmonella outside their hosts. This review focuses on three areas: (1) in vitro evidence that Salmonella spp. can survive for long periods of time under harsh conditions; (2) observations and conclusions about Salmonella persistence obtained from human outbreaks; and (3) new information revealed by genomic- and population-based studies of Salmonella and related enteric pathogens. We highlight the mechanisms of Salmonella persistence and transmission as an essential part of their lifecycle and a prerequisite for their evolutionary success as human pathogens.
Collapse
Affiliation(s)
- Landon L Waldner
- Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5E3, Canada.
| | - Keith D MacKenzie
- Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5E3, Canada.
| | - Wolfgang Köster
- Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5E3, Canada.
| | - Aaron P White
- Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5E3, Canada.
| |
Collapse
|
8
|
Salmonella can reach tomato fruits on plants exposed to aerosols formed by rain. Int J Food Microbiol 2012; 158:140-6. [PMID: 22831820 DOI: 10.1016/j.ijfoodmicro.2012.07.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 07/05/2012] [Accepted: 07/08/2012] [Indexed: 11/20/2022]
Abstract
Outbreaks of Salmonella enterica have been associated with tomatoes and traced back to production areas but the spread of Salmonella in agricultural fields is still poorly understood. Post-rain Salmonella transfer from a point source to the air and then to tomato plants was evaluated. GFP-labeled kanamycin-resistant S. enterica serovar Typhimurium (10(8)CFU/mL) with and without expression of the rdar morphotype (rough colonies; cells with fimbriae and cellulose) was used as the point source in the center of a rain simulator. Rain intensities of 60 and 110 mm/h were applied for 5, 10, 20, and 30 min. Petri dishes with lactose broth and tomato plants with fruit (50-80 cm high) were placed in the simulator after the rain had ceased. Salmonella recovery from air was maximum (300 CFU/plate) after a rain episode of 60 mm/h for 10 min at distances of at least 85.5 cm above the source and when the rdar morphotype strain was used. Small scale experiments showed that the smooth-colony strain without fimbriae precipitated from the air in significantly higher numbers than the rdar strain. Transfer of aerial Salmonella with the rdar morphotype to tomato fruits on plants followed a beta distribution (2.5950, 4.7393) within the generalized range from 0 to 30 min of rain. Results show for the first time that Salmonella may transfer from rain to the air and contaminate tomato fruits at levels that could possibly be infectious to humans.
Collapse
|
9
|
Boateng M, Price S, Huddersman K, Walsh S. Antimicrobial activities of hydrogen peroxide and its activation by a novel heterogeneous Fenton’s-like modified PAN catalyst. J Appl Microbiol 2011; 111:1533-43. [DOI: 10.1111/j.1365-2672.2011.05158.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
10
|
Simultaneous detection of Salmonella spp., Salmonella Typhi and Salmonella Typhimurium in sliced fruits using multiplex PCR. Food Control 2011. [DOI: 10.1016/j.foodcont.2010.05.021] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
11
|
Respective roles of culturable and viable-but-nonculturable cells in the heterogeneity of Salmonella enterica serovar typhimurium invasiveness. Appl Environ Microbiol 2009; 75:5179-85. [PMID: 19525274 DOI: 10.1128/aem.00334-09] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The existence of Salmonella enterica serovar Typhimurium viable-but-nonculturable (VBNC) cells is a public health concern since they could constitute unrecognized sources of infection if they retain their pathogenicity. To date, many studies have addressed the ability of S. Typhimurium VBNC cells to remain infectious, but their conclusions are conflicting. An assumption could explain these conflicting results. It has been proposed that infectivity could be retained only temporarily after entry into the VBNC state and that most VBNC cells generated under intense stress could exceed the stage where they are still infectious. Using a Radioselectan density gradient centrifugation technique makes it possible to increase the VBNC-cell/culturable-cell ratio without increasing the exposure to stress and, consequently, to work with a larger proportion of newly VBNC cells. Here, we observed that (i) in the stationary phase, the S. Typhimurium population comprised three distinct subpopulations at 10, 24, or 48 h of culture; (ii) the VBNC cells were detected at 24 and 48 h; (iii) measurement of invasion gene (hilA, invF, and orgA) expression demonstrated that cells are highly heterogeneous within a culturable population; and (iv) invasion assays of HeLa cells showed that culturable cells from the different subpopulations do not display the same invasiveness. The results also suggest that newly formed VBNC cells are either weakly able or not able to successfully initiate epithelial cell invasion. Finally, we propose that at entry into the stationary phase, invasiveness may be one way for populations of S. Typhimurium to escape stochastic alteration leading to cell death.
Collapse
|
12
|
Dinu LD, Delaquis P, Bach S. Nonculturable response of animal enteropathogens in the agricultural environment and implications for food safety. J Food Prot 2009; 72:1342-54. [PMID: 19610353 DOI: 10.4315/0362-028x-72.6.1342] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Concerns about animal enteropathogen contamination of fresh horticultural products have,increased worldwide and are mainly due to the ability of bacteria to survive under stress conditions in the agricultural environment and during raw-vegetable processing. This review challenges the idea that the viable but nonculturable phenomenon that has been proven to occur in plant-associated environments contributes to human pathogen survival and might be correlated with foodborne infection. Factors associated with the nonculturable response of bacteria in the field and during postharvest processing and distribution are discussed, specifically for the most common animal enteropathogens linked with the consumption of raw products: Escherichia coli O157:H7, Salmonella, Listeria monocytogenes, and Shigella spp. The accurate detection of live bacterial populations is essential for pathogen screening in food and environmental safety control and in epidemiological analysis and may have to be considered for identification of critical control points at the time of food inspection.
Collapse
Affiliation(s)
- Laura-Dorina Dinu
- Agriculture and Agri-Food Canada, Pacific Agri-Food Research Centre, 4200 Highway 97 South, Summerland, British Columbia, Canada
| | | | | |
Collapse
|
13
|
Long-term survival of Salmonella enterica serovar Typhimurium reveals an infectious state that is underrepresented on laboratory media containing bile salts. Appl Environ Microbiol 2009; 75:4923-5. [PMID: 19482950 DOI: 10.1128/aem.00363-09] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cells in desiccated Salmonella enterica serovar Typhimurium rdar (red, dry, and rough) morphotype colonies were examined for culturability and infectivity after 30 months. Culturability decreased only 10-fold; however, cells were underrepresented on Salmonella selective media containing bile salts. These cells were mildly attenuated compared to the infectivity of freshly grown cells but still able to cause systemic infections in mice.
Collapse
|
14
|
Ziprin RL, Harvey RB. Inability of cecal microflora to promote reversion of viable nonculturable Campylobacter jejuni. Avian Dis 2005; 48:647-50. [PMID: 15529989 DOI: 10.1637/7153-010504r1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Campylobacter jejuni cells are able to enter a viable but nonculturable (VBNC) state when they are suspended in water. In the present experiments we inoculated day-of-hatch leghorn and broiler chicks with normal gut microflora and subsequently challenged these with high doses of VBNC C. jejuni. The objective was to determine if the pre-establishment of a normal gut flora would enable VBNC Campylobacter to recover, revert to the vibrionic form, and colonize the cecum. Day-of-hatch leghorn and broiler chicks were gavaged through the esophagus with 0.75 ml of a continuous-flow culture of normal cecal organisms. Two days after gavage, the same chicks were gavaged with 0.75 ml (greater than 10(9) colony-forming units) of a VBNC suspension of C. jejuni. Seven days later, cecal contents were collected, serially diluted, and examined for the presence of viable culturable C. jejuni. Our results demonstrated that the VBNC C. jejuni cells were unable to revert to a vibrionic culturable form capable of colonizing the cecum.
Collapse
Affiliation(s)
- Richard L Ziprin
- Food and Feed Safety Research Unit, Southern Plains Agricultural Research Center, Agricultural Research Service, USDA, College Station, TX 77845, USA
| | | |
Collapse
|
15
|
Mukamolova GV, Kaprelyants AS, Kell DB, Young M. Adoption of the transiently non-culturable state — a bacterial survival strategy? Adv Microb Physiol 2003; 47:65-129. [PMID: 14560663 DOI: 10.1016/s0065-2911(03)47002-1] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Microbial culturability can be ephemeral. Cells are not merely either dead or alive but can adopt physiological states in which they appear to be (transiently) non-culturable under conditions in which they are known normally to be able to grow and divide. The reacquisition of culturability from such states is referred to as resuscitation. We here develop the idea that this "transient non-culturability" is a consequence of a special survival strategy, and summarise the morphological, physiological and genetic evidence underpinning such behaviour and its adaptive significance.
Collapse
Affiliation(s)
- Galina V Mukamolova
- Institute of Biological Sciences, University of Wales, Aberystwyth, Ceredigion SY23 3DD, UK
| | | | | | | |
Collapse
|