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Gaudino M, Nagamine B, Ducatez MF, Meyer G. Understanding the mechanisms of viral and bacterial coinfections in bovine respiratory disease: a comprehensive literature review of experimental evidence. Vet Res 2022; 53:70. [PMID: 36068558 PMCID: PMC9449274 DOI: 10.1186/s13567-022-01086-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 07/11/2022] [Indexed: 11/17/2022] Open
Abstract
Bovine respiratory disease (BRD) is one of the most important diseases impacting the global cattle industry, resulting in significant economic loss. Commonly referred to as shipping fever, BRD is especially concerning for young calves during transport when they are most susceptible to developing disease. Despite years of extensive study, managing BRD remains challenging as its aetiology involves complex interactions between pathogens, environmental and host factors. While at the beginning of the twentieth century, scientists believed that BRD was only caused by bacterial infections (“bovine pasteurellosis”), we now know that viruses play a key role in BRD induction. Mixtures of pathogenic bacteria and viruses are frequently isolated from respiratory secretions of animals with respiratory illness. The increased diagnostic screening data has changed our understanding of pathogens contributing to BRD development. In this review, we aim to comprehensively examine experimental evidence from all existing studies performed to understand coinfections between respiratory pathogens in cattle. Despite the fact that pneumonia has not always been successfully reproduced by in vivo calf modelling, several studies attempted to investigate the clinical significance of interactions between different pathogens. The most studied model of pneumonia induction has been reproduced by a primary viral infection followed by a secondary bacterial superinfection, with strong evidence suggesting this could potentially be one of the most common scenarios during BRD onset. Different in vitro studies indicated that viral priming may increase bacterial adherence and colonization of the respiratory tract, suggesting a possible mechanism underpinning bronchopneumonia onset in cattle. In addition, a few in vivo studies on viral coinfections and bacterial coinfections demonstrated that a primary viral infection could also increase the pathogenicity of a secondary viral infection and, similarly, dual infections with two bacterial pathogens could increase the severity of BRD lesions. Therefore, different scenarios of pathogen dynamics could be hypothesized for BRD onset which are not limited to a primary viral infection followed by a secondary bacterial superinfection.
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Affiliation(s)
- Maria Gaudino
- IHAP, Université de Toulouse, INRAE, ENVT, Toulouse, France
| | | | | | - Gilles Meyer
- IHAP, Université de Toulouse, INRAE, ENVT, Toulouse, France.
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2
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Longo AV. Metabarcoding approaches in amphibian disease ecology: Disentangling the functional contributions of skin bacteria on disease outcome. Integr Comp Biol 2022; 62:252-261. [PMID: 35640913 DOI: 10.1093/icb/icac062] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 05/10/2022] [Accepted: 05/25/2022] [Indexed: 01/09/2023] Open
Abstract
Molecular technologies have revolutionized the field of wildlife disease ecology, allowing the detection of outbreaks, novel pathogens, and invasive strains. In particular, metabarcoding approaches, defined here as tools used to amplify and sequence universal barcodes from a single sample (e.g., 16S rRNA for bacteria, ITS for fungi, 18S rRNA for eukaryotes), are expanding our traditional view of host-pathogen dynamics by integrating microbial interactions that modulate disease outcome. Here, I provide an analysis from the perspective of the field of amphibian disease ecology, where the emergence of multi-host pathogens has caused global declines and species extinctions. I re-analyzed an experimental mesocosm dataset to infer the functional profiles of the skin microbiomes of coqui frogs (Eleutherodactylus coqui), an amphibian species that is consistently found infected with the fungal pathogen Batrachochytrium dendrobatidis and has high turnover of skin bacteria driven by seasonal shifts. I found that the metabolic activities of microbiomes operate at different capacities depending on the season. Global enrichment of predicted functions was more prominent during the warm-wet season, indicating that microbiomes during the cool-dry season were either depauperate, resistant to new bacterial colonization, or that their functional space was more saturated. These findings suggest important avenues to investigate how microbes regulate population growth and contribute to host physiological processes. Overall, this study highlights the current challenges and future opportunities in the application of metabarcoding to investigate the causes and consequences of disease in wild systems.
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Affiliation(s)
- Ana V Longo
- University of Florida, Department of Biology, PO Box 118525, Gainesville, FL
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Ticha L, Kykalova B, Sadlova J, Gramiccia M, Gradoni L, Volf P. Development of Various Leishmania ( Sauroleishmania) tarentolae Strains in Three Phlebotomus Species. Microorganisms 2021; 9:2256. [PMID: 34835382 DOI: 10.3390/microorganisms9112256] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 01/10/2023] Open
Abstract
Leishmania (Sauroleishmania) tarentolae is transmitted by reptile-biting sand flies of the genus Sergentomyia, but the role of Phlebotomus sand flies in circulation of this parasite is unknown. Here, we compared the development of L. (S.) tarentolae strains in three Phlebotomus species: P. papatasi, P. sergenti, and P. perniciosus. Laboratory-bred sand flies were membrane-fed on blood with parasite suspension and dissected on days 1 and 7 post blood meal. Parasites were measured on Giemsa-stained gut smears and five morphological forms were distinguished. In all parasite-vector combinations, promastigotes were found in Malpighian tubules, often in high numbers, which suggests that this tissue is a typical location for L. (S.) tarentolae development in sand flies. All three studied strains colonized the hindgut, but also migrated anteriorly to both parts of the midgut and colonized the stomodeal valve. Significant differences were demonstrated between sand fly species: highest infection rates, high parasite loads, and the most frequent anterior migration with colonization of the stomodeal valve were found in P. perniciosus, while all these parameters were lowest in P. sergenti. In conclusion, the peripylarian type of development was demonstrated for three L. (S.) tarentolae strains in three Phlebotomus sand flies. We suggest paying more attention to Phlebotomus species, particularly P. perniciosus and P. papatasi, as potential secondary vectors of Sauroleishmania.
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Calisher CH. Pathogen-Reservoir Interactions: What We Do Not Know Likely Will Hurt Us. Viruses 2021; 13:195. [PMID: 33525437 DOI: 10.3390/v13020195] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 01/23/2021] [Accepted: 01/26/2021] [Indexed: 11/16/2022] Open
Abstract
The establishment of selective colonies of potential vertebrate hosts for viruses would provide experimental models for the understanding of pathogen-host interactions. This paper briefly surveys the reasons to conduct such studies and how the results might provide information that could be applied to disease prevention activities.
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5
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Bakhshi H, Mousson L, Vazeille M, Zakeri S, Raz A, de Lamballerie X, Dinparast-Djadid N, Failloux AB. High Transmission Potential of West Nile Virus Lineage 1 for Cx. pipiens s.l. of Iran. Viruses 2020; 12:E397. [PMID: 32260215 PMCID: PMC7232300 DOI: 10.3390/v12040397] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 03/31/2020] [Accepted: 04/02/2020] [Indexed: 12/15/2022] Open
Abstract
: Vector competence is an important parameter in evaluating whether a species plays a role in transmission of an arbovirus. Although the protocols are similar, interpretation of results is unique given the specific interactions that exist between a mosquito population and a viral genotype. Here, we assessed the infection (IR), dissemination (DR), and transmission (TR) rates of Cx. pipiens s.l., collected from Iran, for West Nile virus (WNV) lineage 1a. We showed that Cx. pipiens s.l. mosquitoes in Iran were susceptible to WNV with IR up to 89.7%, 93.6%, and 83.9% at 7, 14, and 21 days post-infection (dpi) respectively. In addition, DR and TR reached respectively 92.3% and 75.0% at 21 dpi, and the number of viral particles delivered with saliva reached up to 1.33 × 105 particles. Therefore, an unexpected high risk of WNV dissemination in the region where Cx. pipiens s.l. mosquitoes are well established should be considered carefully and surveillance measures implemented accordingly.
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Affiliation(s)
- Hasan Bakhshi
- Malaria and Vector Research Group, Biotechnology Research Center, Pasteur Institute of Iran, Tehran P.O. Box 1316943551, Iran; (H.B.); (S.Z.); (A.R.)
| | - Laurence Mousson
- Institut Pasteur, Arboviruses and Insect Vectors, 75724 Paris, France; (L.M.); (M.V.)
| | - Marie Vazeille
- Institut Pasteur, Arboviruses and Insect Vectors, 75724 Paris, France; (L.M.); (M.V.)
| | - Sedigheh Zakeri
- Malaria and Vector Research Group, Biotechnology Research Center, Pasteur Institute of Iran, Tehran P.O. Box 1316943551, Iran; (H.B.); (S.Z.); (A.R.)
| | - Abbasali Raz
- Malaria and Vector Research Group, Biotechnology Research Center, Pasteur Institute of Iran, Tehran P.O. Box 1316943551, Iran; (H.B.); (S.Z.); (A.R.)
| | - Xavier de Lamballerie
- Unité des Virus Emergents (UVE), Aix Marseille Université, IRD 190, INSERM 1207, IHU Méditerranée Infection, 13005 Marseille, France;
| | - Navid Dinparast-Djadid
- Malaria and Vector Research Group, Biotechnology Research Center, Pasteur Institute of Iran, Tehran P.O. Box 1316943551, Iran; (H.B.); (S.Z.); (A.R.)
| | - Anna-Bella Failloux
- Institut Pasteur, Arboviruses and Insect Vectors, 75724 Paris, France; (L.M.); (M.V.)
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6
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Sanderink D, Cassisa V, Chenouard R, Mahieu R, Kempf M, Dubée V, Eveillard M. Colistin-glycopeptide combinations against multidrug-resistant Acinetobacter baumannii in a mouse model of pneumonia. Future Microbiol 2019; 14:581-586. [PMID: 31172805 DOI: 10.2217/fmb-2019-0022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: To assess the effect of colistin-glycopeptide combination against a multidrug-resistant strain of Acinetobacter baumannii. Materials & methods: We used in vitro procedures (Etest method, checkerboard test and kill-time assays) and a mouse model of a carbapenem-resistant A. baumannii pneumonia. Results: The colistin-teicoplanin combination allowed a 74% increase of the survival in the mouse model within the 4 days following bacterial inoculation as compared with saline or colistin alone (p = 0.06). Concurrently, the colistin-vancomycin combination presented a similar efficacy as compared with saline or colistin alone in the mouse model. Conclusion: According to those preliminary results, using the colistin-teicoplanin combination in therapeutic deadlocks encountered in certain multiresistant A. baumannii pneumonia could be envisaged if the results are confirmed.
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Affiliation(s)
- Diane Sanderink
- CRCINA, Inserm, Université de Nantes, Université d'Angers, Angers, 44200 Nantes, France.,Service des Maladies Infectieuses et Tropicales, Centre Hospitalier Universitaire, 4 Rue Larrey, 49100 Angers, France
| | - Viviane Cassisa
- Laboratoire de Bactériologie, Centre Hospitalier Universitaire, 4 Rue Larrey, 49100 Angers, France
| | - Rachel Chenouard
- CRCINA, Inserm, Université de Nantes, Université d'Angers, Angers, 44200 Nantes, France.,Laboratoire de Bactériologie, Centre Hospitalier Universitaire, 4 Rue Larrey, 49100 Angers, France
| | - Rafael Mahieu
- Service des Maladies Infectieuses et Tropicales, Centre Hospitalier Universitaire, 4 Rue Larrey, 49100 Angers, France
| | - Marie Kempf
- CRCINA, Inserm, Université de Nantes, Université d'Angers, Angers, 44200 Nantes, France.,Laboratoire de Bactériologie, Centre Hospitalier Universitaire, 4 Rue Larrey, 49100 Angers, France
| | - Vincent Dubée
- CRCINA, Inserm, Université de Nantes, Université d'Angers, Angers, 44200 Nantes, France.,Service des Maladies Infectieuses et Tropicales, Centre Hospitalier Universitaire, 4 Rue Larrey, 49100 Angers, France
| | - Matthieu Eveillard
- CRCINA, Inserm, Université de Nantes, Université d'Angers, Angers, 44200 Nantes, France.,Laboratoire de Bactériologie, Centre Hospitalier Universitaire, 4 Rue Larrey, 49100 Angers, France
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Montiel N, Buckley A, Guo B, Kulshreshtha V, VanGeelen A, Hoang H, Rademacher C, Yoon KJ, Lager K. Vesicular Disease in 9-Week-Old Pigs Experimentally Infected with Senecavirus A. Emerg Infect Dis 2018; 22:1246-8. [PMID: 27315363 PMCID: PMC4918149 DOI: 10.3201/eid2207.151863] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Senecavirus A has been infrequently associated with vesicular disease in swine since 1988. However, clinical disease has not been reproduced after experimental infection with this virus. We report vesicular disease in 9-week-old pigs after Sencavirus A infection by the intranasal route under experimental conditions.
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Dubois A, Castel G, Murri S, Pulido C, Pons JB, Benoit L, Loiseau A, Lakhdar L, Galan M, Marianneau P, Charbonnel N. Bank vole immunoheterogeneity may limit Nephropatia Epidemica emergence in a French non-endemic region. Parasitology 2018; 145:393-407. [PMID: 28931451 DOI: 10.1017/S0031182017001548] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Ecoevolutionary processes affecting hosts, vectors and pathogens are important drivers of zoonotic disease emergence. In this study, we focused on nephropathia epidemica (NE), which is caused by Puumala hantavirus (PUUV) whose natural reservoir is the bank vole, Myodes glareolus. We questioned the possibility of NE emergence in a French region that is considered to be NE-free but that is adjacent to a NE-endemic region. We first confirmed the epidemiology of these two regions and we demonstrated the absence of spatial barriers that could have limited dispersal, and consequently, the spread of PUUV into the NE-free region. We next tested whether regional immunoheterogeneity could impact PUUV chances to circulate and persist in the NE-free region. We showed that bank voles from the NE-free region were sensitive to experimental PUUV infection. We observed high levels of immunoheterogeneity between individuals and also between regions. Antiviral gene expression (Tnf and Mx2) reached higher levels in bank voles from the NE-free region. During experimental infections, anti-PUUV antibody production was higher in bank voles from the NE-endemic region. These results indicated a lower susceptibility to PUUV for bank voles from this NE-free region, which might limit PUUV persistence and therefore, the risk of NE.
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9
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Abstract
Host manipulation is a common parasite strategy to alter host behavior in a manner to enhance parasite fitness usually by increasing the parasite's transmission to the next host. In nature, hosts often harbor multiple parasites with agreeing or conflicting interests over host manipulation. Natural selection might drive such parasites to cooperation, compromise, or sabotage. Sabotage would occur if one parasite suppresses the manipulation of another. Experimental studies on the effect of multi-parasite interactions on host manipulation are scarce, clear experimental evidence for sabotage is elusive. We tested the effect of multiple infections on host manipulation using laboratory-bred copepods experimentally infected with the trophically transmitted tapeworm Schistocephalus solidus. This parasite is known to manipulate its host depending on its own developmental stage. Coinfecting parasites with the same aim enhance each other's manipulation but only after reaching infectivity. If the coinfecting parasites disagree over host manipulation, the infective parasite wins this conflict: the noninfective one has no effect. The winning (i.e., infective) parasite suppresses the manipulation of its noninfective competitor. This presents conclusive experimental evidence for both cooperation in and sabotage of host manipulation and hence a proof of principal that one parasite can alter and even neutralize manipulation by another.
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Affiliation(s)
- Nina Hafer
- Department of Evolutionary Ecology, Max-Planck-Institute for Evolutionary Biology, August-Thienemann-Strasse 2, D-24306 Ploen, Germany.
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10
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Finol HJ, Roschman-González A. Ultrastructural study on tissue alterations caused by trypanosomatids in experimental murine infections. Front Public Health 2014; 2:75. [PMID: 25072046 PMCID: PMC4085721 DOI: 10.3389/fpubh.2014.00075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 06/25/2014] [Indexed: 11/13/2022] Open
Abstract
The ultrastructural study in different tissues of mice experimentally infected with isolates of Trypanosoma evansi, Trypanosoma cruzi, and Leishmania mexicana reveals changes in cardiac myocytes, skeletal muscle fibers, and hepatic, adrenal, kidney, and spleen cells. Some of these changes were cytoarchitectural and others consisted of necrosis. Alterations in the microvasculature were also found. The mononuclear cell infiltrate included neutrophils, eosinophils, and macrophages. This work shows that diverse mice tissues are important target for trypanosomatids.
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Affiliation(s)
- Héctor J Finol
- Center for Electron Microscopy, Faculty of Sciences, Central University of Venezuela , Caracas , Venezuela
| | - Antonio Roschman-González
- Center for Electron Microscopy, Faculty of Sciences, Central University of Venezuela , Caracas , Venezuela
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11
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Lourenço-de-Oliveira R, Rua AV, Vezzani D, Willat G, Vazeille M, Mousson L, Failloux AB. Aedes aegypti from temperate regions of South America are highly competent to transmit dengue virus. BMC Infect Dis 2013; 13:610. [PMID: 24373423 PMCID: PMC3929315 DOI: 10.1186/1471-2334-13-610] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Accepted: 12/24/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Aedes aegypti is extensively spread throughout South America where it has been responsible for large dengue epidemics during the last decades. Intriguingly, dengue transmission has not been reported in Uruguay and is essentially prevalent in subtropical northern Argentina which borders Uruguay. METHODS We assessed vector competence for dengue virus (DENV) of Ae. aegypti populations collected in subtropical Argentina (Corrientes) as well as temperate Uruguay (Salto) and Argentina (Buenos Aires) in 2012 using experimental oral infections with DENV-2. Mosquitoes were incubated at 28 °C and examined at 14 and 21 days p.i. to access viral dissemination and transmission. Batches of the Buenos Aires mosquitoes were also incubated at 15 °C and 20 °C. RESULTS Although mosquitoes from temperate Uruguay and Argentina were competent to transmit DENV, those from subtropical Argentina were more susceptible, displaying the highest virus titters in the head and presenting the highest dissemination of infection and transmission efficiency rates when incubated at 28 °C. Interestingly, infectious viral particles could be detected in saliva of mosquitoes from Buenos Aires exposed to 15 °C and 20 °C. CONCLUSIONS There is a potential risk of establishing DENV transmission in Uruguay and for the spread of dengue outbreaks to other parts of subtropical and temperate Argentina, notably during spring and summer periods.
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Affiliation(s)
- Ricardo Lourenço-de-Oliveira
- Laboratório de Transmissores de Hematozoários, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil 4365, Rio de Janeiro 21045-900, Brazil
- Department of Virology, Arboviruses and Insect Vectors, Institut Pasteur, Paris, France
| | - Anubis Vega Rua
- Department of Virology, Arboviruses and Insect Vectors, Institut Pasteur, Paris, France
| | - Darío Vezzani
- CONICET Instituto de Ecología, Genética y Evolución de Buenos Aires, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Gabriela Willat
- Unidad de Zoonosis y Vectores, Dirección General de la Salud, Ministerio de Salud Pública, Montevideo, Uruguay
| | - Marie Vazeille
- Department of Virology, Arboviruses and Insect Vectors, Institut Pasteur, Paris, France
| | - Laurence Mousson
- Department of Virology, Arboviruses and Insect Vectors, Institut Pasteur, Paris, France
| | - Anna Bella Failloux
- Department of Virology, Arboviruses and Insect Vectors, Institut Pasteur, Paris, France
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Neou E, Michail G, Tsakris A, Pournaras S. Virulence of Acinetobacter baumannii Exhibiting Phenotypic Heterogeneous Growth against Meropenem in a Murine Thigh Infection Model. Antibiotics (Basel) 2013; 2:73-82. [PMID: 27029293 DOI: 10.3390/antibiotics2010073] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 02/16/2013] [Accepted: 03/01/2013] [Indexed: 11/17/2022] Open
Abstract
Acinetobacter baumannii may exhibit phenotypic heterogeneous growth under exposure to antibiotics. We investigated the in vitro characteristics of A. baumannii isolates grown heterogeneously in the presence of meropenem and their virulence evaluated in experimental infections treated with meropenem. Five clinical A. baumannii isolates and the respective heterogeneously grown subpopulations were tested by agar dilution minimum inhibitory concentration (MIC) testing, pulsed field gel electrophoresis (PFGE), population analysis using meropenem and growth curves. The virulence of isolates and the therapeutic efficacy of three meropenem dosing schemes was evaluated in a neutropenic murine thigh infection model. The clinical isolates were meropenem-susceptible (MICs 1 to 4 mg/liter) and exhibited three distinct PFGE patterns. In all clinical isolates, population analysis yielded heterogeneously grown colonies. After seven subcultures in antibiotic-free media, resistant MIC levels were retained in two isolates (heteroresistant), while three isolates were reversed to susceptible MICs (persisters). Clinical isolates and heterogeneous subpopulations had similar growth rates. The heterogeneously grown A. baumannii subpopulations had reduced virulence, killing considerably fewer animals than the respective clinical isolates without treatment. The meropenem treatment outcome was similar in infections caused by the clinical and the heterogeneous isolates, irrespective to their MICs. In vitro meropenem exposure induces phenotypic heterogeneous growth in A. baumannii. Compared with the parental clinical isolates, the heterogeneously grown subpopulations exhibited lower virulence, killing fewer mice and responding equally to meropenem treatment, despite their higher MICs.
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Leemans I, Brown D, Hooshmand-Rad P, Kirvar E, Uggla A. Infectivity and cross-immunity studies of Theileria lestoquardi and Theileria annulata in sheep and cattle: I. In vivo responses. Vet Parasitol 1999; 82:179-92. [PMID: 10348097 PMCID: PMC7131390 DOI: 10.1016/s0304-4017(99)00013-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In a series of experiments, sporozoite stabilates of a Theileria lestoquardi (Lahr) and a T. annulata (Ankara) stock prepared from Hyalomma anatolicum anatolicum ticks, were used to examine the infectivity of both parasite species for sheep and cattle and to study the development of cross-immunity between these parasite species. In the first experiment sheep and cattle were inoculated with T. lestoquardi sporozoites. Surviving animals and naive sheep and cattle were, in the second experiment, inoculated with T. annulata. In the third experiment, naive sheep and sheep previously infected with T. annulata, were inoculated with T. lestoquardi. The following responses to inoculations were monitored: clinical and haematological signs of infection, appearance of parasitic stages of the parasites in lymph node biopsies and in peripheral blood and serological response to T. lestoquardi and T. annulata schizont antigens. While T. lestoquardi readily infected sheep and caused severe disease, it did not infect cattle. On the other hand, T. annulata infected both cattle and sheep. However, whereas cattle became severely affected, infected sheep showed mild clinical symptoms only and piroplasms did not develop. Despite their different behaviour in the host species examined, cross-immunity studies suggested that the parasite species are very closely related. Experiments in sheep indicated that T. lestoquardi infection protected against subsequent T. annulata infection. On the other hand, recovery from T. annulata infection did not prevent infection by sporozoites of T. lestoquardi, resulting in the establishment of schizonts and their subsequent development into piroplasms, although it protected against the major clinical effects of T. lestoquardi infection.
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Affiliation(s)
- I Leemans
- Department of Parasitology, Swedish University of Agricultural Sciences and National Veterinary Institute, Uppsala.
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