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2. Complete Genome Sequence of Yersinia pestis Strains Antiqua and Nepal516: Evidence of Gene Reduction in an Emerging Pathogen

Author

Chain, Patrick S.G., Hu, Ping, Malfatti, Stephanie A., Radnedge, Lyndsay, Larimer, Frank, Vergez, Lisa M., Worsham, Patricia, Chu, May C., and Andersen, Gary L.

Subjects
Environmental sciences, Applied life sciences, Yersinia pestis genome
Abstract

Yersinia pestis, the causative agent of bubonic and pneumonic plague, has undergone detailed study at the molecular level. To further investigate the genomic diversity among this group and to help characterize lineages of the plague organism that have no sequenced members, we present here the genomes of two isolates of the "classical" Antiqua biovar, strains Antiqua and Nepal516. The genomes of Antiqua and Nepal516 are 4.7 Mb and 4.5 Mb and encode 4,138 and 3,956 open reading frames respectively. Though both strains belong to one of the three classical biovars, they represent separate lineages defined by recent phylogenetic studies. We compare all five currently sequenced Y. pestis genomes and the corresponding features in Y. pseudotuberculosis. There are strain-specific rearrangements, insertions, deletions, single nucleotide polymorphisms and a unique distribution of insertion sequences. We found 453 single nucleotide polymorphisms in protein coding regions, which were used to assess evolutionary relationships of these Y. pestis strains. Gene reduction analysis revealed that the gene deletion processes are under selective pressure and many of the inactivations are probably related to the organism s interaction with its host environment. The results presented here clearly demonstrate the differences between the two Antiqua lineages and support the notion that grouping Y. pestis strains based strictly on the classical definition of biovars (predicated upon two biochemical assays) does not accurately reflect the phylogenetic relationships within this species. Comparison of four virulent Y. pestis strains with the human-avirulent strain 91001 provides further insight into the genetic basis of virulence to humans.

Published
2006

4. Lessons from the pandemic: Responding to emerging zoonotic viral diseases—a Keystone Symposia report

Author

Cable, Jennifer, primary, Fauci, Anthony, additional, Dowling, William E., additional, Günther, Stephan, additional, Bente, Dennis A., additional, Yadav, Pragya Dhruv, additional, Madoff, Lawrence C., additional, Wang, Lin‐Fa, additional, Arora, Rahul K., additional, Van Kerkhove, Maria, additional, Chu, May C., additional, Jaenisch, Thomas, additional, Epstein, Jonathan H., additional, Frost, Simon David William, additional, Bausch, Daniel G., additional, Hensley, Lisa E., additional, Bergeron, Éric, additional, Sitaras, Ioannis, additional, Gunn, Michael D., additional, Geisbert, Thomas W., additional, Muñoz‐Fontela, César, additional, Krammer, Florian, additional, de Wit, Emmie, additional, Nordenfelt, Pontus, additional, Saphire, Erica Ollmann, additional, Gilbert, Sarah C., additional, Corbett, Kizzmekia S., additional, Branco, Luis M., additional, Baize, Sylvain, additional, van Doremalen, Neeltje, additional, Krieger, Marco A., additional, Clemens, Sue Ann Costa, additional, Hesselink, Renske, additional, and Hartman, Dan, additional

Published
2022
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6. COVID-19 Serology Control Panel Using the Dried-Tube Specimen Method

Author

Windsor, William J., primary, Knight, Vijaya, additional, Merkel, Patricia A., additional, Lamb, Molly M., additional, Tucker, Heidi R., additional, Carson, Kyle, additional, Howard, Kelly M., additional, Yates, Jennifer L., additional, Santiago, Mario L., additional, McCarthy, Mary K., additional, Morrison, Thomas E., additional, Kedl, Ross M., additional, Frazer-Abel, Ashley, additional, Guo, Kejun, additional, Andersen, Gillian, additional, Huey, Leah, additional, Barrett, Bradley S., additional, Colón-Franco, Jessica M., additional, Lee, William T., additional, and Chu, May C., additional

Published
2022
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8. COVID-19 Serology Control Panel Using the Dried Tube Specimen Method

Author

Windsor, William J., primary, Knight, Vijaya, additional, Merkel, Patricia A., additional, Lamb, Molly M., additional, Santiago, Mario L., additional, McCarthy, Mary K., additional, Morrison, Thomas E., additional, Kedl, Ross M., additional, Frazer-Abel, Ashley, additional, Guo, Kejun, additional, Andersen, Gillian, additional, Huey, Leah, additional, Barrett, Bradley S., additional, Colón-Franco, Jessica M., additional, and Chu, May C., additional

Published
2021
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10. Addressing personal protective equipment (PPE) decontamination: Methylene blue and light inactivates severe acute respiratory coronavirus virus 2 (SARS-CoV-2) on N95 respirators and medical masks with maintenance of integrity and fit

Author

Lendvay, Thomas Sean, primary, Chen, James, additional, Harcourt, Brian H., additional, Scholte, Florine E. M., additional, Lin, Ying Ling, additional, Kilinc-Balci, F. Selcen, additional, Lamb, Molly M., additional, Homdayjanakul, Kamonthip, additional, Cui, Yi, additional, Price, Amy, additional, Heyne, Belinda, additional, Sahni, Jaya, additional, Kabra, Kareem B., additional, Lin, Yi-Chan, additional, Evans, David, additional, Mores, Christopher N., additional, Page, Ken, additional, Chu, Larry F., additional, Haubruge, Eric, additional, Thiry, Etienne, additional, Ludwig-Begall, Louisa F., additional, Wielick, Constance, additional, Clark, Tanner, additional, Wagner, Thor, additional, Timm, Emily, additional, Gallagher, Thomas, additional, Faris, Peter, additional, Macia, Nicolas, additional, Mackie, Cyrus J., additional, Simmons, Sarah M., additional, Reader, Susan, additional, Malott, Rebecca, additional, Hope, Karen, additional, Davies, Jan M., additional, Tritsch, Sarah R., additional, Dams, Lorène, additional, Nauwynck, Hans, additional, Willaert, Jean-Francois, additional, De Jaeger, Simon, additional, Liao, Lei, additional, Zhao, Mervin, additional, Laperre, Jan, additional, Jolois, Olivier, additional, Smit, Sarah J., additional, Patel, Alpa N., additional, Mayo, Mark, additional, Parker, Rod, additional, Molloy-Simard, Vanessa, additional, Lemyre, Jean-Luc, additional, Chu, Steven, additional, Conly, John M., additional, and Chu, May C., additional

Published
2021
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11. Phenotypic and molecular characterizations of Yersinia pestis isolates from Kazakhstan and adjacent regions

Author

Lowell, Jennifer L., Zhansarina, Aigul, Yockey, Brook, Meka-Mechenko, Tatyana, Stybayeva, Gulnaz, Atshabar, Bakyt, Nekrassova, Larissa, Tashmetov, Rinat, Kenghebaeva, Kuralai, Chu, May C., Kosoy, Michael, Antolin, Michael F., and Gage, Kenneth L.

Subjects
Yersinia pestis -- Genetic aspects, Bioterrorism -- Analysis, Biological sciences
Abstract

Recent interest in characterizing infectious agents associated with bioterrorism has resulted in the development of effective pathogen genotyping systems, but this information is rarely combined with phenotypic data. Yersinia pestis, the aetiological agent of plague, has been well defined genotypically on local and worldwide scales using multi-locus variable number tandem repeat analysis (MLVA), with emphasis on evolutionary patterns using old isolate collections from countries where Y. pestis has existed the longest. Worldwide MLVA studies are largely based on isolates that have been in long-term laboratory culture and storage, or on field material from parts of the world where Y. pestis has potentially circulated in nature for thousands of years. Diversity in these isolates suggests that they may no longer represent the wild-type organism phenotypically, including the possibility of altered pathogenicity. This study focused on the phenotypic and genotypic properties of 48 Y. pestis isolates collected from 10 plague foci in and bordering Kazakhstan. Phenotypic characterization was based on diagnostic tests typically performed in reference laboratories working with Y. pestis. MLVA was used to define the genotypic relationships between the central-Asian isolates and a group of North American isolates, and to examine Kazakh Y. pestis diversity according to predefined plague foci and on an intermediate geographical scale. Phenotypic properties revealed that a large portion of this collection lacks one or more plasmids necessary to complete the blocked flea/mammal transmission cycle, has lost Congo red binding capabilities ([Pgm.sup.-]), or both. MLVA analysis classified isolates into previously identified biovars, and in some cases groups of isolates collected within the same plague focus formed a clade. Overall, MLVA did not distinguish unique phylogeographical groups of Y. pestis isolates as defined by plague foci and indicated higher genetic diversity among older biovars.

Published
2007

12. Addressing Personal Protective Equipment (PPE) Decontamination: Methylene Blue and Light Inactivates SARS-CoV-2 on N95 Respirators and Masks with Maintenance of Integrity and Fit

Author

Lendvay, Thomas S., primary, Chen, James, additional, Harcourt, Brian H., additional, Scholte, Florine E.M., additional, Kilinc-Balci, F. Selcen, additional, Lin, Ying Ling, additional, Lamb, Molly M., additional, Chu, Larry F., additional, Price, Amy, additional, Evans, David, additional, Lin, Yi-Chan, additional, Mores, Christopher N., additional, Sahni, Jaya, additional, Kabra, Kareem B., additional, Haubruge, Eric, additional, Thiry, Etienne, additional, Heyne, Belinda, additional, Laperre, Jan, additional, Simmons, Sarah, additional, Davies, Jan M., additional, Cui, Yi, additional, Wagner, Thor, additional, Clark, Tanner, additional, Smit, Sarah J., additional, Parker, Rod, additional, Gallagher, Thomas, additional, Timm, Emily, additional, Ludwig-Begall, Louisa F., additional, Macia, Nicolas, additional, Mackie, Cyrus, additional, Hope, Karen, additional, Page, Ken, additional, Reader, Susan, additional, Faris, Peter, additional, Jolois, Olivier, additional, Patel, Alpa, additional, Lemyre, Jean-Luc, additional, Molloy-Simard, Vanessa, additional, Homdayjanakul, Kamonthip, additional, Tritsch, Sarah R., additional, Wielick, Constance, additional, Mayo, Mark, additional, Malott, Rebecca, additional, Willaert, Jean-Francois, additional, Nauwynck, Hans, additional, Dams, Lorène, additional, De Jaeger, Simon, additional, Liao, Lei, additional, Zhao, Mervin, additional, Chu, Steven, additional, Conly, John M., additional, and Chu, May C., additional

Published
2020
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13. Laboratory analysis of tularemia in wild-trapped, commercially traded prairie dogs, Texas, 2002

Author

Petersen, Jeannine M., Schriefer, Martin E., Carter, Leon G., Zhou, Yan, Sealy, Tara, Bawiec, Darcy, Yockey, Brook, Urich, Sandra, Zeidner, Nordin S., Avashia, Swati, Kool, Jacob L., Buck, Jan, Lindley, Connie, Celeda, Leos, Monteneiri, John A., Gage, Kenneth L., and Chu, May C.

Subjects
Tularemia -- Research
Abstract

Oropharyngeal tularemia was identified as the cause of a die-off in captured wild prairie dogs at a commercial exotic animal facility in Texas. From this point source, Francisella tularensis--infected prairie [...]

Published
2004

14. First reported prairie dog-to-human tularemia transmission, Texas, 2002

Author

Avashia, Swati B., Petersen, Jeannine M., Lindley, Connie M., Schriefer, Martin E., Gage, Kenneth L., Cetron, Marty, DeMarcus, Thomas A., Kim, David K., Buck, Jan, Montenieri, John A., Lowell, Jennifer L., Antolin, Michael F., Kosoy, Michael Y., Carter, Leon G., Chu, May C., Hendricks, Katherine A., Dennis, David T., and Kool, Jacob L.

Subjects
Tularemia -- Research
Abstract

A tularemia outbreak, caused by Francisella tularensis type B, occurred among wild-caught, commercially traded prairie dogs. F. tularensis microagglutination titers in one exposed person indicated recent infection. These findings represent [...]

Published
2004

15. Addressing personal protective equipment (PPE) decontamination: Methylene blue and light inactivates severe acute respiratory coronavirus virus 2 (SARS-CoV-2) on N95 respirators and medical masks with maintenance of integrity and fit

Author

Lendvay, Thomas Sean, Chen, James, Harcourt, Brian H., Scholte, Florine E. M., Lin, Ying Ling, Kilinc-Balci, F. Selcen, Lamb, Molly M., Homdayjanakul, Kamonthip, Cui, Yi, Price, Amy, Heyne, Belinda, Sahni, Jaya, Kabra, Kareem B., Lin, Yi-Chan, Evans, David, Mores, Christopher N., Page, Ken, Chu, Larry F., Haubruge, Eric, Thiry, Etienne, Ludwig-Begall, Louisa F., Wielick, Constance, Clark, Tanner, Wagner, Thor, Timm, Emily, Gallagher, Thomas, Faris, Peter, Macia, Nicolas, Mackie, Cyrus J., Simmons, Sarah M., Reader, Susan, Malott, Rebecca, Hope, Karen, Davies, Jan M., Tritsch, Sarah R., Dams, Lorène, Nauwynck, Hans, Willaert, Jean-Francois, De Jaeger, Simon, Liao, Lei, Zhao, Mervin, Laperre, Jan, Jolois, Olivier, Smit, Sarah J., Patel, Alpa N., Mayo, Mark, Parker, Rod, Molloy-Simard, Vanessa, Lemyre, Jean-Luc, Chu, Steven, Conly, John M., and Chu, May C.

Abstract

AbstractObjective:The coronavirus disease 2019 (COVID-19) pandemic has resulted in shortages of personal protective equipment (PPE), underscoring the urgent need for simple, efficient, and inexpensive methods to decontaminate masks and respirators exposed to severe acute respiratory coronavirus virus 2 (SARS-CoV-2). We hypothesized that methylene blue (MB) photochemical treatment, which has various clinical applications, could decontaminate PPE contaminated with coronavirus.Design:The 2 arms of the study included (1) PPE inoculation with coronaviruses followed by MB with light (MBL) decontamination treatment and (2) PPE treatment with MBL for 5 cycles of decontamination to determine maintenance of PPE performance.Methods:MBL treatment was used to inactivate coronaviruses on 3 N95 filtering facepiece respirator (FFR) and 2 medical mask models. We inoculated FFR and medical mask materials with 3 coronaviruses, including SARS-CoV-2, and we treated them with 10 µM MB and exposed them to 50,000 lux of white light or 12,500 lux of red light for 30 minutes. In parallel, integrity was assessed after 5 cycles of decontamination using multiple US and international test methods, and the process was compared with the FDA-authorized vaporized hydrogen peroxide plus ozone (VHP+O3) decontamination method.Results:Overall, MBL robustly and consistently inactivated all 3 coronaviruses with 99.8% to >99.9% virus inactivation across all FFRs and medical masks tested. FFR and medical mask integrity was maintained after 5 cycles of MBL treatment, whereas 1 FFR model failed after 5 cycles of VHP+O3.Conclusions:MBL treatment decontaminated respirators and masks by inactivating 3 tested coronaviruses without compromising integrity through 5 cycles of decontamination. MBL decontamination is effective, is low cost, and does not require specialized equipment, making it applicable in low- to high-resource settings.

Published
2022
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16. The genome sequence of Yersinia pestis bacteriophage [phi]A1122 reveals an intimate history with the coliphage T3 and T7 genomes

Author

Garcia, Emilio, Elliott, Jeffrey M., Ramanculov, Erlan, Chain, Patrick S.G., Chu, May C., and Molineux, Ian J.

Subjects
Plague -- Causes of, Yersinia pestis -- Genetic aspects, Genomes -- Genetic aspects, Bacteriophages -- Genetic aspects, Bacteriology -- Research, Biological sciences
Abstract

The genome sequence of bacteriophage [phi]A1122 has been determined. [phi]A1122 grows on almost all isolates of Yersinia pestis and is used by the Centers for Disease Control and Prevention as a diagnostic agent for the causative agent of plague. [phi]A1122 is very closely related to coliphage T7; the two genomes are colinear, and the genome-wide level of nucleotide identity is about 89%. However, a quarter of the [phi]A1122 genome, one that includes about half of the morphogenetic and maturation functions, is significantly more closely related to coliphage T3 than to T7. It is proposed that the yersiniophage [phi]A1122 recombined with a close relative of the Y. enterocolitica phage [phi]YeO3-12 to yield progeny phages, one of which became the classic T3 coliphage of Demerec and Fano (M. Demerec and U. Fano, Genetics 30:119-136, 1945).

Published
2003

17. Tularemia on Martha's Vineyard: seroprevalence and occupational risk. (Research)

Author

Feldman, Katherine A., Stiles-Enos, Donna, Julian, Kathleen, Matyas, Bela T., Telford, Sam R., III, Chu, May C., Petersen, Lyle R., and Hayes, Edward B.

Subjects
Communicable diseases -- Research, Communicable diseases -- Risk factors, Epidemiology -- Research, Gardeners -- Health aspects, Tularemia -- Risk factors, Tularemia -- Research, Tularemia -- Development and progression
Abstract

We conducted a serosurvey of landscapers to determine if they were at increased risk for exposure to Francisella tularensis and to determine risk factors for infection. In Martha's Vineyard, Massachusetts, [...]

Published
2003

18. Household Materials Selection for Homemade Cloth Face Coverings and Their Filtration Efficiency Enhancement with Triboelectric Charging

Author

Zhao, Mervin, primary, Liao, Lei, additional, Xiao, Wang, additional, Yu, Xuanze, additional, Wang, Haotian, additional, Wang, Qiqi, additional, Lin, Ying Ling, additional, Kilinc-Balci, F. Selcen, additional, Price, Amy, additional, Chu, Larry, additional, Chu, May C., additional, Chu, Steven, additional, and Cui, Yi, additional

Published
2020
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21. Serologic Testing for Lyme Disease

Author

Schriefer, Martin E., Dennis, David T., Gubler, Duane J., Hayes, Edward B., Johnson, Barbara J. B., and Chu, May C.

Published
2000

22. Francisella tularensis in rodents, China

Author

Zhang, Fang, Liu, Wei, Chu, May C., He, Jun, Duan, Qing, Wu, Xiao-Ming, Zhang, Pan-He, Zhao, Qiu-Min, Yang, Hong, Xin, Zhong-Tao, and Cao, Wu-Chun

Subjects
Communicable diseases -- Research, Rodents -- Research, Tularemia -- Research, China -- Health policy, China -- Research
Abstract

A total of 420 rodents in China were examined for Francisella tularensis by polymerase chain reaction. The infection rates were 4.76% in total, and 11.65%, 10.00%, 6.56%, 1.77%, and 0% [...]

Published
2006

25. Methods of enhanced culture recovery of francisella tularensis

Author

Petersen, Jeannine M., Schriefer, Martin E., Gage, Kenneth L., Montenieri, John A., Chu, May C., Carter, Leon G., and Stanley, Miles

Subjects
Tularemia -- Research, Tissues -- Research, Biological sciences
Abstract

Improved recovery times and a sensitivity of 90 percent of francisella tularensis is demonstrated when cultures are inoculated using fresh tissues. Here, comparisons are also performed using samples from a tularemia outbreak in prairie dogs.

Published
2004

27. The complete genome sequence of Francisella tularensis, the causative agent of tularemia.

Author

Larsson, Pär, Oyston, Petra C .F., Chain, Patrick, Chu, May C., Duffield, Melanie, Fuxelius, Hans-Erik, Garcia, Emilio, Hälltorp, Greger, Johansson, Daniel, Isherwood, Karen E., Karp, Peter D, Larsson, Eva, Liu, Ying, Michell, Stephen, Prior, Joann, Prior, Richard, Malfatti, Stephanie, Sjöstedt, Anders, Svensson, Kerstin, Thompson, Nick, Vergez, Lisa, Wagg, Jonathan K., Wren, Brendan W., Lindler, Luther E., Andersson, Siv G. E., Forsman, Mats, Titball, Richard W., Larsson, Pär, Oyston, Petra C .F., Chain, Patrick, Chu, May C., Duffield, Melanie, Fuxelius, Hans-Erik, Garcia, Emilio, Hälltorp, Greger, Johansson, Daniel, Isherwood, Karen E., Karp, Peter D, Larsson, Eva, Liu, Ying, Michell, Stephen, Prior, Joann, Prior, Richard, Malfatti, Stephanie, Sjöstedt, Anders, Svensson, Kerstin, Thompson, Nick, Vergez, Lisa, Wagg, Jonathan K., Wren, Brendan W., Lindler, Luther E., Andersson, Siv G. E., Forsman, Mats, and Titball, Richard W.

Published
2005
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31. Francisella tularensisin Rodents, China

Author

Zhang, Fang, primary, Liu, Wei, additional, Chu, May C., additional, He, Jun, additional, Duan, Qing, additional, Wu, Xiao-Ming, additional, Zhang, Pan-He, additional, Zhao, Qiu-Min, additional, Yang, Hong, additional, Xin, Zhong-Tao, additional, and Cao, Wu-Chun, additional

Published
2006
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32. Identifying Sources of Human Exposure to Plague

Author

Lowell, Jennifer L., primary, Wagner, David M., additional, Atshabar, Bakyt, additional, Antolin, Michael F., additional, Vogler, Amy J., additional, Keim, Paul, additional, Chu, May C., additional, and Gage, Kenneth L., additional

Published
2005
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33. The complete genome sequence of Francisella tularensis, the causative agent of tularemia

Author

Larsson, Pär, primary, Oyston, Petra C F, additional, Chain, Patrick, additional, Chu, May C, additional, Duffield, Melanie, additional, Fuxelius, Hans-Henrik, additional, Garcia, Emilio, additional, Hälltorp, Greger, additional, Johansson, Daniel, additional, Isherwood, Karen E, additional, Karp, Peter D, additional, Larsson, Eva, additional, Liu, Ying, additional, Michell, Stephen, additional, Prior, Joann, additional, Prior, Richard, additional, Malfatti, Stephanie, additional, Sjöstedt, Anders, additional, Svensson, Kerstin, additional, Thompson, Nick, additional, Vergez, Lisa, additional, Wagg, Jonathan K, additional, Wren, Brendan W, additional, Lindler, Luther E, additional, Andersson, Siv G E, additional, Forsman, Mats, additional, and Titball, Richard W, additional

Published
2005
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43. Analysis of Dengue Virus Enhancing Epitopes Using Peptide Antigens Derived From the Envelope Glycoprotein Gene Sequence.

Author

CENTERS FOR DISEASE CONTROL ATLANTA GA, Chu, May C., CENTERS FOR DISEASE CONTROL ATLANTA GA, and Chu, May C.

Abstract

The biological events leading to the development of severe disease manifestations of dengue infections (dengue hemorrhagic fever/dengue shock syndrome, DHF/DSS) has been the focus of many investigations. Though DHF/DSS cases occur during primary dengue infections, the majority of severe dengue disease has been associated with persons experiencing a secondary heterotypic dengue infection. What do we know about the pathogenic processes that result in the exacerbation of dengue symptoms? Can these factors be identified in vitro and then correlated with clinical disease? The results of previous studies suggest that preexisting DEN antibodies circulating in a person may be a risk factor in the development of DHF/DSS. However, other host and viral factors must be involved since only a small proportion of the population residing in endemic dengue disease regions develop severe dengue disease.... Dengue fever, Nucleotide sequencing, Peptides, Enhancing epitopes, RA I, PO, Antigens, Dengue virus, Analysis.

Published
1991

44. Analysis of Dengue Virus Enhancing Epitopes Using Peptide Antigens Derived from the Envelope Glycoprotein Gene Sequence

Author

CENTERS FOR DISEASE CONTROL ATLANTA GA, Chu, May C., CENTERS FOR DISEASE CONTROL ATLANTA GA, and Chu, May C.

Abstract

Antibody-dependent enhancement (ADE) of dengue (DEN) virus infection in human mononuclear cells in vitro has been standardized using a human promonocytic cell line HL-CZ, purified monoclonal antibodies (MAbs), and select DEN viruses. Characterization of the FC-receptors (FcRs) expressed on HL-CZ cells have indicated that subsets of FcR mediate ADE better than others. Using this standardized system, we have compared the ability of mouse anti-DEN 2 envelope (E) peptides to elicit virus neutralization and ADE. Peptides 1-2, 437 appear to elicit ADE activity in contrast to other peptides that appear to elicit neutralization but not ADE. Though these assays need to be repeated, it appears that differential functions may be attributed to particular E genomic regions. The comparison of the nucleotide sequences of Den-1 RNA encoding the non-structural proteins to the other DEN sequences has revealed that DEN-4 and Den-1 share > 90% similarity in NS3 and NS4a, 4b genome regions. DEN-3 and DEN-1 have a deletion in NS5 that is conserved in other DEN-1 and DEN-3 isolates. These genomic sequence comparisons indicate that non-structural region differences need to be studied as well for our understanding of DEN replication and pathogenesis.

Published
1990

47. Development of a Multitarget Real-Time TaqMan PCR Assay for Enhanced Detection of Francisella tularensisin Complex Specimens

Author

Versage, Jessica L., Severin, Darlena D. M., Chu, May C., and Petersen, Jeannine M.

Abstract

ABSTRACTTularemia is the zoonotic disease caused by the gram-negative coccobacillus Francisella tularensis.Its wide distribution in the environment poses a challenge for understanding the transmission, ecology, and epidemiology of the disease. F. tularensisis also considered a potential biological weapon due to its extreme infectivity. We have developed a multitarget real-time TaqMan PCR assay capable of rapidly and accurately detecting F. tularensisin complex specimens. Targeted regions included the ISFtu2element and the 23kDa, fopA, and tul4genes. Analysis of the four TaqMan assays demonstrated that three (ISFtu2, 23kDa, and tul4) performed within our established criterion of a detection limit of one organism. The combined use of the three assays was highly specific, displaying no cross-reactivity with the non-Francisellabacteria tested and capable of differentially diagnosing both F. tularensisand Francisella philomiragia. When the multitarget TaqMan assay (ISFtu2, 23kDa, and tul4) was compared to culturing, using environmentally contaminated specimens, the TaqMan PCR assay was significantly more sensitive than culturing (P= 0.05). The sensitive and specific nature of this rapid multitarget TaqMan assay provides a valuable new tool that with future evaluations can be used for analyzing clinical specimens, field samples during bioterrorism threat assessment, and samples from outbreaks and for improving our understanding of the ecology and environmental prevalence of F. tularensis.

Published
2003
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48. Genotyping of a Homogeneous Group of Yersinia pestisStrains Isolated in the United States

Author

Huang, Xiao-Zhe, Chu, May C., Engelthaler, Dave M., and Lindler, Luther E.

Abstract

ABSTRACTYersinia pestis, the causative agent of deadly plague, is considered a reemerging infectious disease and a significant biological terrorism threat. The present project focused on epidemiological investigation of the genetic variability of well-documented strains of Y. pestisfrom the United States by pulsed-field gel electrophoresis (PFGE) and restriction fragment length polymorphism (RFLP) analysis with insertion sequences IS100and IS285as probes. We examined 37 U.S. Y. pestisstrains and isolates of a single ribotype, ribotype B, recovered between 1939 and 1998 from patients, animals, and fleas. Our results showed that all isolates had similar PFGE patterns, but minor differences such as missing, additional, and shifted bands were found among almost all strains if they came from different parent strains. The 37 strains and isolates were divided into 26 PFGE types. RFLP analysis with IS100as a probe divided these strains and isolates into 16 types, with 43% belonging to IS100type 1. Typing with IS285as a probe was less specific and led to only four RFLP types, with 81% belonging to type 1. Similarity analysis with BioNumerics software showed that all strains shared =80, 86, and 91% similarities on dendrograms prepared from digitized PFGE, IS100RFLP analysis, and IS285RFLP analysis images, respectively. Our results demonstrate that PFGE offers an increased ability to discriminate between strains (Simpson's index of diversity, 0.98) and therefore can significantly improve epidemiological studies related to the origin of new plague isolates.

Published
2002
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49. Francisella tularensis in Rodents, China.

Author

Fang Zhang, Wei Liu, Chu, May C., Jun He, Qing Duan, Xiao-Ming Wu, Pan-He Zhang, Qiu-Min Zhao, Hong Yang, Zhong-Tao Xin, and Wu-Chun Cao

Subjects
FRANCISELLA tularensis, LABORATORY rodents, POLYMERASE chain reaction, FRANCISELLA
Abstract

A total of 420 rodents in China were examined for Francisella tularensis by polymerase chain reaction. The infection rates were 4.76% in total, and 11.65%, 10.00%, 6.56%, 1.77%, and 0% in Jilin, Xinjiang, Heilongjiang, Inner Mongolia, and Zhejiang, respectively. Sequence analysis showed that all the detected agents belonged to F. tularensis subsp. holarctica. [ABSTRACT FROM AUTHOR]

Published
2006
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50. An Outbreak of Francisella Tularensisin Captive Prairie Dogs: An Immunohistochemical Analysis

Author

Zeidner, Nordin S., Carter, Leon G., Monteneiri, John A., Petersen, Jeannine M., Schriefer, Martin, Gage, Kenneth L., Hall, Greg, and Chu, May C.

Abstract

An immunohistochemical assay was developed and tested for detection of Francisella tularensislipopolysaccaride antigen in tissues of captive prairie dogs (Cynomys ludovicianus). Tissues from 59 cases of F. tularensiswere examined by this technique, which was corroborated by direct fluorescent antibody assay and direct isolation of the organism. In infected prairie dogs, studies indicated multiple, severe, necroprurulent foci occurring in the liver, lung, spleen, terminal ileum, and mandibular lymph node. Immunohistochemical analysis of the same formalin-fixed tissues indicated the presence of F. tularensisantigen in neutrophils and macrophages of these lesions and occurring extracellularly in areas of necrosis. This report demonstrates that immunohistochemical analysis is a rapid procedure that can be used to determine the pathogenesis of F. tularensisin rodent populations.

Published
2004
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