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Chen S, Sanderson MW, Lee C, Cernicchiaro N, Renter DG, Lanzas C. Basic Reproduction Number and Transmission Dynamics of Common Serogroups of Enterohemorrhagic Escherichia coli. Appl Environ Microbiol 2016; 82:5612-20. [PMID: 27401976 PMCID: PMC5007764 DOI: 10.1128/aem.00815-16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 07/01/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Understanding the transmission dynamics of pathogens is essential to determine the epidemiology, ecology, and ways of controlling enterohemorrhagic Escherichia coli (EHEC) in animals and their environments. Our objective was to estimate the epidemiological fitness of common EHEC strains in cattle populations. For that purpose, we developed a Markov chain model to characterize the dynamics of 7 serogroups of enterohemorrhagic Escherichia coli (O26, O45, O103, O111, O121, O145, and O157) in cattle production environments based on a set of cross-sectional data on infection prevalence in 2 years in two U.S. states. The basic reproduction number (R0) was estimated using a Bayesian framework for each serogroup based on two criteria (using serogroup alone [the O-group data] and using O serogroup, Shiga toxin gene[s], and intimin [eae] gene together [the EHEC data]). In addition, correlations between external covariates (e.g., location, ambient temperature, dietary, and probiotic usage) and prevalence/R0 were quantified. R0 estimates varied substantially among different EHEC serogroups, with EHEC O157 having an R0 of >1 (∼1.5) and all six other EHEC serogroups having an R0 of less than 1. Using the O-group data substantially increased R0 estimates for the O26, O45, and O103 serogroups (R0 > 1) but not for the others. Different covariates had distinct influences on different serogroups: the coefficients for each covariate were different among serogroups. Our modeling and analysis of this system can be readily expanded to other pathogen systems in order to estimate the pathogen and external factors that influence spread of infectious agents. IMPORTANCE In this paper we describe a Bayesian modeling framework to estimate basic reproduction numbers of multiple serotypes of Shiga toxin-producing Escherichia coli according to a cross-sectional study. We then coupled a compartmental model to reconstruct the infection dynamics of these serotypes and quantify their risk in the population. We incorporated different sensitivity levels of detecting different serotypes and evaluated their potential influence on the estimation of basic reproduction numbers.
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Affiliation(s)
- Shi Chen
- Department of Public Health Sciences, University of North Carolina Charlotte, Charlotte, North Carolina, USA Department of Population Health and Pathobiology, North Carolina State University, Raleigh, North Carolina, USA
| | - Michael W Sanderson
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas, USA
| | - Chihoon Lee
- School of Business, Stevens Institute of Technology, Hoboken, New Jersey, USA Department of Statistics, Colorado State University, Fort Collins, Colorado, USA
| | - Natalia Cernicchiaro
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas, USA
| | - David G Renter
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas, USA
| | - Cristina Lanzas
- Department of Population Health and Pathobiology, North Carolina State University, Raleigh, North Carolina, USA
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Venegas-Vargas C, Henderson S, Khare A, Mosci RE, Lehnert JD, Singh P, Ouellette LM, Norby B, Funk JA, Rust S, Bartlett PC, Grooms D, Manning SD. Factors Associated with Shiga Toxin-Producing Escherichia coli Shedding by Dairy and Beef Cattle. Appl Environ Microbiol 2016; 82:5049-56. [PMID: 27342555 PMCID: PMC4968536 DOI: 10.1128/aem.00829-16] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 06/01/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Shiga toxin-producing Escherichia coli (STEC) is an important foodborne pathogen that can cause hemorrhagic colitis and hemolytic-uremic syndrome. Cattle are the primary reservoir for STEC, and food or water contaminated with cattle feces is the most common source of infections in humans. Consequently, we conducted a cross-sectional study of 1,096 cattle in six dairy herds (n = 718 animals) and five beef herds (n = 378 animals) in the summers of 2011 and 2012 to identify epidemiological factors associated with shedding. Fecal samples were obtained from each animal and cultured for STEC. Multivariate analyses were performed to identify risk factors associated with STEC positivity. The prevalence of STEC was higher in beef cattle (21%) than dairy cattle (13%) (odds ratio [OR], 1.76; 95% confidence interval [CI], 1.25, 2.47), with considerable variation occurring across herds (range, 6% to 54%). Dairy cattle were significantly more likely to shed STEC when the average temperature was >28.9°C 1 to 5 days prior to sampling (OR, 2.5; 95% CI, 1.25, 4.91), during their first lactation (OR, 1.8; 95% CI, 1.1, 2.8), and when they were <30 days in milk (OR, 3.9; 95% CI, 2.1, 7.2). These data suggest that the stress or the negative energy balance associated with lactation may result in increased STEC shedding frequencies in Michigan during the warm summer months. Future prevention strategies aimed at reducing stress during lactation or isolating high-risk animals could be implemented to reduce herd-level shedding levels and avoid transmission of STEC to susceptible animals and people. IMPORTANCE STEC shedding frequencies vary considerably across cattle herds in Michigan, and the shedding frequency of strains belonging to non-O157 serotypes far exceeds the shedding frequency of O157 strains, which is congruent with human infections in the state. Dairy cattle sampled at higher temperatures, in their first lactation, and early in the milk production stage were significantly more likely to shed STEC, which could be due to stress or a negative energy balance. Future studies should focus on the isolation of high-risk animals to decrease herd shedding levels and the potential for contamination of the food supply.
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Affiliation(s)
- Cristina Venegas-Vargas
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Scott Henderson
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Akanksha Khare
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Rebekah E Mosci
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Jonathan D Lehnert
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Pallavi Singh
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Lindsey M Ouellette
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Bo Norby
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Julie A Funk
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Steven Rust
- Department of Animal Science, Michigan State University, East Lansing, Michigan, USA
| | - Paul C Bartlett
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Daniel Grooms
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Shannon D Manning
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
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Stanford K, Johnson RP, Alexander TW, McAllister TA, Reuter T. Influence of Season and Feedlot Location on Prevalence and Virulence Factors of Seven Serogroups of Escherichia coli in Feces of Western-Canadian Slaughter Cattle. PLoS One 2016; 11:e0159866. [PMID: 27482711 PMCID: PMC4970752 DOI: 10.1371/journal.pone.0159866] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 07/08/2016] [Indexed: 11/19/2022] Open
Abstract
Pooled feces collected over two years from 1749 transport trailers hauling western-Canadian slaughter cattle were analysed by PCR for detection of Escherichia coli serogroups O26, O45, O103, O111, O121, O145, and O157. Sequential immunomagnetic separation was then used to collect bacterial isolates (n = 1035) from feces positive for target serogroups. Isolated bacteria were tested by PCR to confirm serogroup and the presence of eae, ehxA, stx1, and stx2 virulence genes. Based on PCR screening, serogroup prevalence in feces ranged from 7.0% (O145) to 94.4% (O103) with at least 3 serogroups present in 79.5% of samples. Origin of cattle affected serogroup PCR prevalence and O157 was most prevalent in feces from south-west Alberta (P < 0.001). All serogroups demonstrated seasonal variations in PCR prevalence, with O26, O45, O103, O121, and O157 least prevalent (P < 0.001) in cooler winter months, while uncommon serogroups O111 and O145 increased in prevalence during winter (P < 0.001). However, isolates collected during winter were predominantly from serogroups O103 and O45. No seasonal variation was noted in proportion of isolates which were Shiga toxin containing E. coli (STEC; P = 0.18) or positive for Shiga toxin and eae (enterohemorrhagic E. coli; EHEC; P = 0.29). Isolates of serogroups O111, O145, and O157 were more frequently EHEC than were others, although 37.6–54.3% of isolates from other serogroups were also EHEC. Shiga-toxin genes present also varied by geographic origin of cattle (P < 0.05) in all serogroups except O157. As cattle within feedlots are sourced from multiple regions, locational differences in serogroup prevalence and virulence genes imply existence of selection pressures for E. coli and their virulence in western-Canadian cattle. Factors which reduce carriage or expression of virulence genes, particularly in non-O157 serogroups, should be investigated.
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Affiliation(s)
- Kim Stanford
- Alberta Agriculture and Forestry, Lethbridge, Alberta, Canada
- * E-mail:
| | | | | | | | - Tim Reuter
- Alberta Agriculture and Forestry, Lethbridge, Alberta, Canada
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Molecular characterization and antimicrobial resistance of STEC strains isolated from healthy cattle in 2011 and 2013 in Spain. Epidemiol Infect 2016; 144:2956-2966. [DOI: 10.1017/s0950268816001370] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
SUMMARYPrevention of Shiga toxin-producingEscherichia coli(STEC) foodborne outbreaks is hampered by its complex epidemiology. We assessed the distribution of virulence genes (VGs), main serogroups/serotypes for public health [haemolytic uraemic syndrome (HUS)-related], antimicrobial resistance (AMR) profiles and pulsed-field gel electrophoresis (PFGE) patterns in a collection of STEC isolates obtained from cattle hide (n= 149) and faecal (n= 406) samples collected during a national survey conducted in Spain in 2011 and 2013. Isolates were cultured using McConkey and CT-SMAC agar after enrichment, and confirmed as STEC by PCR. STEC prevalence in hides (15·4%) was higher than in faeces (10·7%) and O157:H7 was more frequent in the former (2·7%vs. 0·99%). Non-O157 HUS-related serogroups were present albeit at low frequencies. The non-O157 isolates were more heterogeneous than O157:H7 in their VG patterns, with 25/64 presenting VGs from both STEC and enterotoxigenic pathotypes (hybrid isolates). Of the STEC isolates, 62·5% were resistant at least to one antimicrobial, and no differences in AMR between O157:H7 and non-O157 were detected. All isolates had different profiles by PFGE and did not form a cluster. Overall, our results demonstrated that STEC in the cattle reservoir is still a matter of concern for human health due to the presence of HUS-related serogroups, the occurrence of certain VGs, AMR and the additional risks that hybrid isolates may pose, and thus warrants further investigation.
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Chopyk J, Moore RM, DiSpirito Z, Stromberg ZR, Lewis GL, Renter DG, Cernicchiaro N, Moxley RA, Wommack KE. Presence of pathogenic Escherichia coli is correlated with bacterial community diversity and composition on pre-harvest cattle hides. MICROBIOME 2016; 4:9. [PMID: 27000779 PMCID: PMC4802634 DOI: 10.1186/s40168-016-0155-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 02/10/2016] [Indexed: 05/10/2023]
Abstract
BACKGROUND Since 1982, specific serotypes of Shiga toxin-producing Escherichia coli (STEC) have been recognized as significant foodborne pathogens acquired from contaminated beef and, more recently, other food products. Cattle are the major reservoir hosts of these organisms, and while there have been advancements in food safety practices and industry standards, STEC still remains prevalent within beef cattle operations with cattle hides implicated as major sources of carcass contamination. To investigate whether the composition of hide-specific microbial communities are associated with STEC prevalence, 16S ribosomal RNA (rRNA) bacterial community profiles were obtained from hide and fecal samples collected from a large commercial feedlot over a 3-month period. These community data were examined amidst an extensive collection of prevalence data on a subgroup of STEC that cause illness in humans, referred to as enterohemorrhagic E. coli (EHEC). Fecal 16S rRNA gene OTUs (operational taxonomic units) were subtracted from the OTUs found within each hide 16S rRNA amplicon library to identify hide-specific bacterial populations. RESULTS Comparative analysis of alpha diversity revealed a significant correlation between low bacterial diversity and samples positive for the presence of E. coli O157:H7 and/or the non-O157 groups: O26, O111, O103, O121, O45, and O145. This trend occurred regardless of diversity metric or fecal OTU presence. The number of EHEC serogroups present in the samples had a compounding effect on the inverse relationship between pathogen presence and bacterial diversity. Beta diversity data showed differences in bacterial community composition between samples containing O157 and non-O157 populations, with certain OTUs demonstrating significant changes in relative abundance. CONCLUSIONS The cumulative prevalence of the targeted EHEC serogroups was correlated with low bacterial community diversity on pre-harvest cattle hides. Understanding the relationship between indigenous hide bacterial communities and populations may provide strategies to limit EHEC in cattle and provide biomarkers for EHEC risk assessment.
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Affiliation(s)
- Jessica Chopyk
- Delaware Biotechnology Institute, University of Delaware, Delaware Biotechnology Inst., 15 Innovation Way, Newark, DE, 19711, USA
| | - Ryan M Moore
- Delaware Biotechnology Institute, University of Delaware, Delaware Biotechnology Inst., 15 Innovation Way, Newark, DE, 19711, USA
| | - Zachary DiSpirito
- Delaware Biotechnology Institute, University of Delaware, Delaware Biotechnology Inst., 15 Innovation Way, Newark, DE, 19711, USA
| | - Zachary R Stromberg
- Delaware Biotechnology Institute, University of Delaware, Delaware Biotechnology Inst., 15 Innovation Way, Newark, DE, 19711, USA
| | - Gentry L Lewis
- Delaware Biotechnology Institute, University of Delaware, Delaware Biotechnology Inst., 15 Innovation Way, Newark, DE, 19711, USA
| | - David G Renter
- College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | | | - Rodney A Moxley
- School of Veterinary Medicine & Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - K Eric Wommack
- Delaware Biotechnology Institute, University of Delaware, Delaware Biotechnology Inst., 15 Innovation Way, Newark, DE, 19711, USA.
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56
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Puri-Giri R, Ghosh A, Zurek L. Stable Flies (Stomoxys calcitrans L.) from Confined Beef Cattle Do Not Carry Shiga-Toxigenic Escherichia coli (STEC) in the Digestive Tract. Foodborne Pathog Dis 2016; 13:65-7. [DOI: 10.1089/fpd.2015.2056] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Rukmini Puri-Giri
- Department of Entomology, Kansas State University, Manhattan, Kansas
| | - Anuradha Ghosh
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas
| | - Ludek Zurek
- Department of Entomology, Kansas State University, Manhattan, Kansas
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas
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57
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Shridhar PB, Noll LW, Shi X, An B, Cernicchiaro N, Renter DG, Nagaraja TG, Bai J. Multiplex Quantitative PCR Assays for the Detection and Quantification of the Six Major Non-O157 Escherichia coli Serogroups in Cattle Feces. J Food Prot 2016; 79:66-74. [PMID: 26735031 DOI: 10.4315/0362-028x.jfp-15-319] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) serogroups O26, O45, O103, O111, O121, and O145, called non-O157 STEC, are important foodborne pathogens. Cattle, a major reservoir, harbor the organisms in the hindgut and shed them in the feces. Although limited data exist on fecal shedding, concentrations of non-O157 STEC in feces have not been reported. The objectives of our study were (i) to develop and validate two multiplex quantitative PCR (mqPCR) assays, targeting O-antigen genes of O26, O103, and O111 (mqPCR-1) and O45, O121, and O145 (mqPCR-2); (ii) to utilize the two assays, together with a previously developed four-plex qPCR assay (mqPCR-3) targeting the O157 antigen and three virulence genes (stx1, stx2, and eae), to quantify seven serogroups and three virulence genes in cattle feces; and (iii) to compare the three mqPCR assays to a 10-plex conventional PCR (cPCR) targeting seven serogroups and three virulence genes and culture methods to detect seven E. coli serogroups in cattle feces. The two mqPCR assays (1 and 2) were shown to be specific to the target genes, and the detection limits were 4 and 2 log CFU/g of pure culture-spiked fecal samples, before and after enrichment, respectively. A total of 576 fecal samples collected from a feedlot were enriched in E. coli broth and were subjected to quantification (before enrichment) and detection (after enrichment). Of the 576 fecal samples subjected, before enrichment, to three mqPCR assays for quantification, 175 (30.4%) were quantifiable (≥4 log CFU/g) for at least one of the seven serogroups, with O157 being the most common serogroup. The three mqPCR assays detected higher proportions of postenriched fecal samples (P > 0.01) as positive for one or more serogroups compared with cPCR and culture methods. This is the first study to assess the applicability of qPCR assays to detect and quantify six non-O157 serogroups in cattle feces and to generate data on fecal concentration of the six serogroups.
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Affiliation(s)
- P B Shridhar
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA
| | - L W Noll
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA
| | - X Shi
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA
| | - B An
- Veterinary Diagnostic Laboratory, Kansas State University, Manhattan, Kansas 66506, USA
| | - N Cernicchiaro
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA
| | - D G Renter
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA
| | - T G Nagaraja
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA.
| | - J Bai
- Veterinary Diagnostic Laboratory, Kansas State University, Manhattan, Kansas 66506, USA.
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Noll LW, Baumgartner WC, Shridhar PB, Cull CA, Dewsbury DM, Shi X, Cernicchiaro N, Renter DG, Nagaraja TG. Pooling of Immunomagnetic Separation Beads Does Not Affect Detection Sensitivity of Six Major Serogroups of Shiga Toxin-Producing Escherichia coli in Cattle Feces. J Food Prot 2016; 79:59-65. [PMID: 26735030 DOI: 10.4315/0362-028x.jfp-15-236] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) of the serogroups O26, O45, O103, O111, O121, and O145, often called non-O157 STEC, are foodborne pathogens. Cattle are asymptomatic reservoirs for STEC; the organisms reside in the hindgut and are shed in the feces, which serve as the source of food product contaminations. Culture-based detection of non-O157 STEC involves an immunomagnetic separation (IMS) step to capture the specific serogroups in complex matrices, such as feces. The IMS procedure is time consuming and labor intensive because of the need to subject each fecal sample to six individual beads. Therefore, our objective was to evaluate whether pooling of IMS beads affects sensitivity of non-O157 STEC detection compared with using individual IMS beads. The evaluation was done by comparing detection of serogroups in feces spiked with pure cultures (experiments 1 and 2) and from feces (n = 384) of naturally shedding cattle (experiment 3). In spiked fecal samples, detection with pools of three, four, six, or seven beads was similar to, or at times higher than, detection with individual IMS beads. In experiment 3, the proportions of fecal samples that tested positive for the six serogroups as detected by individual or pooled beads were similar. Based on noninferiority tests, detection with pooled beads was not substantially inferior to detection with individual beads (P > 0.05). In conclusion, the pooling of IMS beads is a better option for detection of STEC serogroups in fecal samples compared with individual beads because the procedure saves time and labor and has the prospect of a higher throughput.
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Affiliation(s)
- Lance W Noll
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - William C Baumgartner
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - Pragathi B Shridhar
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - Charley A Cull
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - Diana M Dewsbury
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - Xiaorong Shi
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - Natalia Cernicchiaro
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - David G Renter
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - T G Nagaraja
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA.
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