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El Zowalaty ME, Abdelgadir A, Borkenhagen LK, Ducatez MF, Bailey ES, Gray GC. Influenza A viruses are likely highly prevalent in South African swine farms. Transbound Emerg Dis 2021; 69:2373-2383. [PMID: 34327845 DOI: 10.1111/tbed.14255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 07/14/2021] [Accepted: 07/20/2021] [Indexed: 11/30/2022]
Abstract
Growth in pork production during the last decade in South Africa has escalated the risk of zoonotic pathogen emergence. This cross-sectional study was conducted to evaluate evidence for transmission of influenza A virus between pigs and swine workers. Between February and October 2018, samples from swine workers and pigs were collected from three farms in KwaZulu-Natal Province, South Africa. Workers nasal washes and serum samples, and swine oral secretion samples (rope sampling method) were studied for evidence of swine influenza A virus infection using molecular and serological methods. Among 84 human nasal washes and 51 swine oral secretion specimens, 44 (52.4%) and 6 (11.8%) had molecular evidence of influenza A virus. Microneutralization assays with workers' enrolment sera against swine H1N1 and H3N2 viruses revealed a high prevalence of elevated antibodies. Multivariate risk factor analysis showed that male workers from the age-group quartile 23-32 years, who self-reported a recent history of exposure to someone with influenza disease and seldom use of personal protective equipment were at highest risk of molecular detection of influenza A virus. These pilot study data suggest that influenza A viruses are likely highly prevalent in South African swine farms. South Africa would benefit from periodic surveillance for novel influenza viruses in swine farms as well as education and seasonal influenza vaccine programmes for swine workers.
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Affiliation(s)
- Mohamed E El Zowalaty
- Zoonosis Science Center, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.,Duke One Health, Duke University School of Medicine, Duke University, Durham, North Carolina, USA
| | - Anfal Abdelgadir
- Division of Infectious Diseases, Duke University School of Medicine, Durham, North Carolina, USA.,Duke Global Health Institute, Duke University, Durham, North Carolina, USA
| | - Laura K Borkenhagen
- Division of Infectious Diseases, Duke University School of Medicine, Durham, North Carolina, USA.,Duke Global Health Institute, Duke University, Durham, North Carolina, USA
| | | | - Emily S Bailey
- Division of Infectious Diseases, Duke University School of Medicine, Durham, North Carolina, USA.,Duke Global Health Institute, Duke University, Durham, North Carolina, USA
| | - Gregory C Gray
- Division of Infectious Diseases, Duke University School of Medicine, Durham, North Carolina, USA.,Duke Global Health Institute, Duke University, Durham, North Carolina, USA.,Global Health Research Center, Duke-Kunshan University, Kunshan, China.,Emerging Infectious Diseases Program, Duke-NUS Medical School, Singapore
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2
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Bakre AA, Jones LP, Murray J, Reneer ZB, Meliopoulos VA, Cherry S, Schultz-Cherry S, Tripp RA. Innate Antiviral Cytokine Response to Swine Influenza Virus by Swine Respiratory Epithelial Cells. J Virol 2021; 95:e0069221. [PMID: 33980596 PMCID: PMC8274599 DOI: 10.1128/jvi.00692-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 05/06/2021] [Indexed: 11/20/2022] Open
Abstract
Swine influenza virus (SIV) can cause respiratory illness in swine. Swine contribute to influenza virus reassortment, as avian, human, and/or swine influenza viruses can infect swine and reassort, and new viruses can emerge. Thus, it is important to determine the host antiviral responses that affect SIV replication. In this study, we examined the innate antiviral cytokine response to SIV by swine respiratory epithelial cells, focusing on the expression of interferon (IFN) and interferon-stimulated genes (ISGs). Both primary and transformed swine nasal and tracheal respiratory epithelial cells were examined following infection with field isolates. The results show that IFN and ISG expression is maximal at 12 h postinfection (hpi) and is dependent on cell type and virus genotype. IMPORTANCE Swine are considered intermediate hosts that have facilitated influenza virus reassortment events that have given rise pandemics or genetically related viruses have become established in swine. In this study, we examine the innate antiviral response to swine influenza virus in primary and immortalized swine nasal and tracheal epithelial cells, and show virus strain- and host cell type-dependent differential expression of key interferons and interferon-stimulated genes.
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Affiliation(s)
- Abhijeet A. Bakre
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Les P. Jones
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Jackelyn Murray
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Z. Beau Reneer
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | | | - Sean Cherry
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis Tennessee
| | - Stacey Schultz-Cherry
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis Tennessee
| | - Ralph A. Tripp
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
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3
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Salvesen HA, Whitelaw CBA. Current and prospective control strategies of influenza A virus in swine. Porcine Health Manag 2021; 7:23. [PMID: 33648602 PMCID: PMC7917534 DOI: 10.1186/s40813-021-00196-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 01/21/2021] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Influenza A Viruses (IAV) are endemic pathogens of significant concern in humans and multiple keystone livestock species. Widespread morbidity in swine herds negatively impacts animal welfare standards and economic performance whilst human IAV pandemics have emerged from pigs on multiple occasions. To combat the rising prevalence of swine IAV there must be effective control strategies available. MAIN BODY The most basic form of IAV control on swine farms is through good animal husbandry practices and high animal welfare standards. To control inter-herd transmission, biosecurity considerations such as quarantining of pigs and implementing robust health and safety systems for workers help to reduce the likelihood of swine IAV becoming endemic. Closely complementing the physical on-farm practices are IAV surveillance programs. Epidemiological data is critical in understanding regional distribution and variation to assist in determining an appropriate response to outbreaks and understanding the nature of historical swine IAV epidemics and zoonoses. Medical intervention in pigs is restricted to vaccination, a measure fraught with the intrinsic difficulties of mounting an immune response against a highly mutable virus. It is the best available tool for controlling IAV in swine but is far from being a perfect solution due to its unreliable efficacy and association with an enhanced respiratory disease. Because IAV generally has low mortality rates there is a reticence in the uptake of vaccination. Novel genetic technologies could be a complementary strategy for IAV control in pigs that confers broad-acting resistance. Transgenic pigs with IAV resistance are useful as models, however the complexity of these reaching the consumer market limits them to research models. More promising are gene-editing approaches to prevent viral exploitation of host proteins and modern vaccine technologies that surpass those currently available. CONCLUSION Using the suite of IAV control measures that are available for pigs effectively we can improve the economic productivity of pig farming whilst improving on-farm animal welfare standards and avoid facing the extensive social and financial costs of a pandemic. Fighting 'Flu in pigs will help mitigate the very real threat of a human pandemic emerging, increase security of the global food system and lead to healthier pigs.
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Affiliation(s)
- Hamish A. Salvesen
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Edinburgh, UK
| | - C. Bruce A. Whitelaw
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Edinburgh, UK
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4
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Bakre AA, Jones LP, Bennett HK, Bobbitt DE, Tripp RA. Detection of swine influenza virus in nasal specimens by reverse transcription-loop-mediated isothermal amplification (RT-LAMP). J Virol Methods 2021; 288:114015. [PMID: 33271254 PMCID: PMC7799534 DOI: 10.1016/j.jviromet.2020.114015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 11/11/2020] [Accepted: 11/12/2020] [Indexed: 12/31/2022]
Abstract
Detection of swine influenza virus (SIV) in commercial swine herds is important for understanding the infection status of the herd and for controlling disease. Current molecular diagnostics require that specimens be submitted to a laboratory which provides results to the growers after some time which is generally too late to intercede in disease control. Moreover, current diagnostic assays are time-consuming, typically costly, and require skilled technical expertise. We have instituted a reverse transcription loop-mediated isothermal amplification (RT-LAMP) diagnostic assay based on conserved regions of the SIV matrix (M) gene and H1N1 hemagglutinin (HA) sequences. The RT-LAMP assay was optimized to use both colorimetric and fluorescent endpoints and was validated. The M and HA RT-LAMP assays have a limit-of-detection (LOD) sensitive to 11 and 8-log-fold dilutions of viral RNA, respectively, and are capable of discriminating between H1 and H3 strains of SIV. Additionally, the RT-LAMP assay was optimized for direct amplification of SIV from field samples without the need for viral RNA isolation. The direct RT-LAMP detected >86 % of qRT-PCR validated SIV samples, and >66 % of negative samples when spiked with viral RNA or SIV. The diagnostic RT-LAMP assay is a rapid, sensitive, specific, and cost-effective method for the detection of SIV in herds substantially aiding diagnosis and surveillance.
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Affiliation(s)
- Abhijeet A Bakre
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Les P Jones
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Hailey K Bennett
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Davis E Bobbitt
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Ralph A Tripp
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States.
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5
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Sobolev I, Kurskaya O, Leonov S, Kabilov M, Alikina T, Alekseev A, Yushkov Y, Saito T, Uchida Y, Mine J, Shestopalov A, Sharshov K. Novel reassortant of H1N1 swine influenza virus detected in pig population in Russia. Emerg Microbes Infect 2020; 8:1456-1464. [PMID: 31603050 PMCID: PMC6818105 DOI: 10.1080/22221751.2019.1673136] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Pigs play an important role in interspecies transmission of the influenza virus, particularly as "mixing vessels" for reassortment. Two influenza A/H1N1 virus strains, A/swine/Siberia/1sw/2016 and A/swine/Siberia/4sw/2017, were isolated during a surveillance of pigs from private farms in Russia from 2016 to 2017. There was a 10% identity difference between the HA and NA nucleotide sequences of isolated strains and the most phylogenetically related sequences (human influenza viruses of 1980s). Simultaneously, genome segments encoding internal proteins were found to be phylogenetically related to the A/H1N1pdm09 influenza virus. In addition, two amino acids (129-130) were deleted in the HA of A/swine/Siberia/4sw/2017 compared to that of A/swine/Siberia/1sw/2016 HA.
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Affiliation(s)
- Ivan Sobolev
- Department of Experimental Modeling and Pathogenesis of Infectious Diseases, Federal Research Center of Fundamental and Translational Medicine , Novosibirsk , Russia
| | - Olga Kurskaya
- Department of Experimental Modeling and Pathogenesis of Infectious Diseases, Federal Research Center of Fundamental and Translational Medicine , Novosibirsk , Russia
| | - Sergey Leonov
- Siberian Federal Scientific Centre of Agro- BioTechnologies , Krasnoobsk , Russia
| | - Marsel Kabilov
- Institute of Chemical Biology and Fundamental Medicine , Novosibirsk , Russia
| | - Tatyana Alikina
- Institute of Chemical Biology and Fundamental Medicine , Novosibirsk , Russia
| | - Alexander Alekseev
- Department of Experimental Modeling and Pathogenesis of Infectious Diseases, Federal Research Center of Fundamental and Translational Medicine , Novosibirsk , Russia
| | - Yuriy Yushkov
- Siberian Federal Scientific Centre of Agro- BioTechnologies , Krasnoobsk , Russia
| | - Takehiko Saito
- Division of Transboundary Animal Disease, National Institute of Animal Health , Tsukuba , Japan
| | - Yuko Uchida
- Division of Transboundary Animal Disease, National Institute of Animal Health , Tsukuba , Japan
| | - Junki Mine
- Division of Transboundary Animal Disease, National Institute of Animal Health , Tsukuba , Japan
| | - Alexander Shestopalov
- Department of Experimental Modeling and Pathogenesis of Infectious Diseases, Federal Research Center of Fundamental and Translational Medicine , Novosibirsk , Russia
| | - Kirill Sharshov
- Department of Experimental Modeling and Pathogenesis of Infectious Diseases, Federal Research Center of Fundamental and Translational Medicine , Novosibirsk , Russia
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6
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Borkenhagen LK, Salman MD, Ma MJ, Gray GC. Animal influenza virus infections in humans: A commentary. Int J Infect Dis 2019; 88:113-119. [PMID: 31401200 DOI: 10.1016/j.ijid.2019.08.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 07/29/2019] [Accepted: 08/04/2019] [Indexed: 12/19/2022] Open
Abstract
Here we review evidence for influenza A viruses (IAVs) moving from swine, avian, feline, equine, and canine species to infect humans. We review case reports, sero-epidemiological, archeo-epidemiological, environmental, and historical studies and consider trends in livestock farming. Although this focused review is not systematic, the aggregated data point to industrialized swine farming as the most likely source of future pandemic viruses, yet IAV surveillance on such farms is remarkably sparse. We recommend increased biosafety and biosecurity training for farm administrators and swine workers with One Health-oriented virus surveillance throughout industrialized farming and meat production lines. Collaborative partnerships with human medical researchers could aid in efforts to mitigate emerging virus threats by offering new surveillance and diagnostic technologies to livestock farming industries.
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Affiliation(s)
- Laura K Borkenhagen
- Division of Infectious Diseases, School of Medicine, & Global Health Institute, Duke University, Durham, NC, USA
| | - Mo D Salman
- Animal Population Health Institute, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Mai-Juan Ma
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Gregory C Gray
- Division of Infectious Diseases, School of Medicine, & Global Health Institute, Duke University, Durham, NC, USA; Global Health Research Center, Duke Kunshan University, Kunshan, China; Emerging Infectious Diseases Program, Duke-NUS Medical School, Singapore.
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7
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Eurasian Avian-Like Swine Influenza A Viruses Escape Human MxA Restriction through Distinct Mutations in Their Nucleoprotein. J Virol 2019; 93:JVI.00997-18. [PMID: 30355693 DOI: 10.1128/jvi.00997-18] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
To cross the human species barrier, influenza A viruses (IAV) of avian origin have to overcome the interferon-induced host restriction factor MxA by acquiring distinct mutations in their nucleoprotein (NP). We recently demonstrated that North American classical swine IAV are able to partially escape MxA restriction. Here we investigated whether the Eurasian avian-like swine IAV lineage currently circulating in European swine would likewise evade restriction by human MxA. We found that the NP of the influenza virus isolate A/Swine/Belzig/2/2001 (Belzig-NP) exhibits increased MxA escape, similar in extent to that with human IAV NPs. Mutational analysis revealed that the MxA escape mutations in Belzig-NP differ from the known MxA resistance cluster of the North American classical swine lineage and human-derived IAV NPs. A mouse-adapted avian IAV of the H7N7 subtype encoding Belzig-NP showed significantly greater viral growth in both MxA-expressing cells and MxA-transgenic mice than control viruses lacking the MxA escape mutations. Similarly, the growth of the recombinant Belzig virus was only marginally affected in MxA-expressing cells and MxA-transgenic mice, in contrast to that of Belzig mutant viruses lacking MxA escape mutations in the NP. Phylogenetic analysis of the Eurasian avian-like swine IAV revealed that the NP amino acids required for MxA escape were acquired successively and were maintained after their introduction. Our results suggest that the circulation of IAV in the swine population can result in the selection of NP variants with a high degree of MxA resistance, thereby increasing the zoonotic potential of these viruses.
IMPORTANCE The human MxA protein efficiently blocks the replication of IAV from nonhuman species. In rare cases, however, these IAV overcome the species barrier and become pandemic. All known pandemic viruses have acquired and maintained MxA escape mutations in the viral NP and thus are not efficiently controlled by MxA. Intriguingly, partial MxA resistance can also be acquired in other hosts that express antivirally active Mx proteins, such as swine. To perform a risk assessment of IAV circulating in the European swine population, we analyzed the degree of MxA resistance of Eurasian avian-like swine IAV. Our data demonstrate that these viruses carry formerly undescribed Mx resistance mutations in the NP that mediate efficient escape from human MxA. We conclude that Eurasian avian-like swine IAV possess substantial zoonotic potential.
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8
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Henritzi D, Hoffmann B, Wacheck S, Pesch S, Herrler G, Beer M, Harder TC. A newly developed tetraplex real-time RT-PCR for simultaneous screening of influenza virus types A, B, C and D. Influenza Other Respir Viruses 2019; 13:71-82. [PMID: 30264926 PMCID: PMC6304318 DOI: 10.1111/irv.12613] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 09/12/2018] [Accepted: 09/13/2018] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Human- or avian-to-swine transmissions have founded several autonomously circulating influenza A virus (IAV) lineages in swine populations that cause economically important respiratory disease. Little is known on other human influenza virus types, like B (IBV) and C (ICV) in European swine, and of the recently detected novel animal influenza virus type D (IDV). OBJECTIVES Development of a cost-effective diagnostic tool for large-scale surveillance programmes targeting all four influenza virus types. METHODS An influenza ABCD tetraplex real-time RT-PCR (RT-qPCR) was developed in the frame of this study. A selection of reference virus strains and more than 4000 porcine samples from a passive IAV surveillance programme in European swine with acute respiratory disease were examined. RESULTS Two IBV, a single IDV but no ICV infections were identified by tetraplex RT-qPCR. IBV and IDV results were confirmed by conventional RT-PCR and partial sequence analysis. CONCLUSIONS The tetraplex RT-qPCR proved fit for purpose as a sensitive, specific and high-throughput tool to study influenza virus transmission at the human-animal interface. Complementing close-meshed active virological and serological surveillance is required to better understand the true incidence and prevalence of influenza virus type B, C and D infections in swine.
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Affiliation(s)
- Dinah Henritzi
- Institute of Diagnostic VirologyFriedrich‐Loeffler‐Institut (FLI)Greifswald‐Insel RiemsGermany
| | - Bernd Hoffmann
- Institute of Diagnostic VirologyFriedrich‐Loeffler‐Institut (FLI)Greifswald‐Insel RiemsGermany
| | | | | | - Georg Herrler
- University of Veterinary Medicine Hannover, FoundationHannoverGermany
| | - Martin Beer
- Institute of Diagnostic VirologyFriedrich‐Loeffler‐Institut (FLI)Greifswald‐Insel RiemsGermany
| | - Timm C. Harder
- Institute of Diagnostic VirologyFriedrich‐Loeffler‐Institut (FLI)Greifswald‐Insel RiemsGermany
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9
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Rovida F, Piralla A, Marzani FC, Moreno A, Campanini G, Mojoli F, Pozzi M, Girello A, Chiapponi C, Vezzoli F, Prati P, Percivalle E, Pavan A, Gramegna M, Iotti GA, Baldanti F. Swine influenza A (H1N1) virus (SIV) infection requiring extracorporeal life support in an immunocompetent adult patient with indirect exposure to pigs, Italy, October 2016. ACTA ACUST UNITED AC 2017; 22. [PMID: 28183395 PMCID: PMC5388119 DOI: 10.2807/1560-7917.es.2017.22.5.30456] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 02/02/2017] [Indexed: 11/20/2022]
Abstract
We describe a case of severe swine influenza A(H1N1) virus infection in an immunocompetent middle-aged man in October 2016 in Italy who had only indirect exposure to pigs. The patient developed a severe acute distress respiratory syndrome which was successfully supported by extracorporeal membrane oxygenation and treated with antiviral therapy. The sole risk factor for influenza was a body mass index > 30 kg/m2. After a month of hospitalisation, the patient was discharged in good health.
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Affiliation(s)
- Francesca Rovida
- These authors contributed equally to this work.,SS Virologia Molecolare, SC Microbiologia e Virologia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Antonio Piralla
- These authors contributed equally to this work.,SS Virologia Molecolare, SC Microbiologia e Virologia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Federico Capra Marzani
- Anestesia e Rianimazione, Dipartimento di Emergenza ed Urgenza, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy
| | - Ana Moreno
- Istituto Zooprofilattico Sperimentale della Lombardia ed Emilia Romagna, Brescia, Italy
| | - Giulia Campanini
- SS Virologia Molecolare, SC Microbiologia e Virologia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Francesco Mojoli
- Unità di Anestesia, Rianimazione e Terapia Antalgica, Dipartimento di Scienze Clinico-Chirurgiche, Diagnostiche e Pediatriche, Università degli Studi di Pavia, Pavia, Italy.,Anestesia e Rianimazione, Dipartimento di Emergenza ed Urgenza, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy
| | - Marco Pozzi
- Anestesia e Rianimazione, Dipartimento di Emergenza ed Urgenza, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy
| | - Alessia Girello
- SS Virologia Molecolare, SC Microbiologia e Virologia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Chiara Chiapponi
- Istituto Zooprofilattico Sperimentale della Lombardia ed Emilia Romagna, Parma, Italy
| | - Fausto Vezzoli
- Istituto Zooprofilattico Sperimentale della Lombardia ed Emilia Romagna, Lodi, Italy
| | - Paola Prati
- Istituto Zooprofilattico Sperimentale della Lombardia ed Emilia Romagna, Pavia, Italy
| | - Elena Percivalle
- SS Virologia Molecolare, SC Microbiologia e Virologia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Anna Pavan
- Agenzia di Tutela della Salute, Pavia, Italy
| | - Maria Gramegna
- Direzione Generale Sanità, Regione Lombardia, Milan, Italy
| | - Giorgio Antonio Iotti
- Unità di Anestesia, Rianimazione e Terapia Antalgica, Dipartimento di Scienze Clinico-Chirurgiche, Diagnostiche e Pediatriche, Università degli Studi di Pavia, Pavia, Italy.,Anestesia e Rianimazione, Dipartimento di Emergenza ed Urgenza, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy
| | - Fausto Baldanti
- Dipartimento di Scienze Clinico-Chirurgiche, Diagnostiche e Pediatriche, Università degli Studi di Pavia, Pavia, Italy.,SS Virologia Molecolare, SC Microbiologia e Virologia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
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10
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Takemae N, Shobugawa Y, Nguyen PT, Nguyen T, Nguyen TN, To TL, Thai PD, Nguyen TD, Nguyen DT, Nguyen DK, Do HT, Le TQA, Hua PT, Van Vo H, Nguyen DT, Nguyen DH, Uchida Y, Saito R, Saito T. Effect of herd size on subclinical infection of swine in Vietnam with influenza A viruses. BMC Vet Res 2016; 12:227. [PMID: 27724934 PMCID: PMC5057248 DOI: 10.1186/s12917-016-0844-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 02/18/2016] [Indexed: 01/14/2023] Open
Abstract
Background Influenza A viruses of swine (IAV-S) cause acute and subclinical respiratory disease. To increase our understanding of the etiology of the subclinical form and thus help prevent the persistence of IAV-S in pig populations, we conducted active virologic surveillance in Vietnam, the second-largest pig-producing country in Asia, from February 2010 to December 2013. Results From a total of 7034 nasal swabs collected from clinically healthy pigs at 250 farms and 10 slaughterhouses, we isolated 172 IAV-S from swine at the weaning and early-fattening stages. The isolation rate of IAV-S was significantly higher among pigs aged 3 weeks to 4.5 months than in older and younger animals. IAV-S were isolated from 16 large, corporate farms and 6 family-operated farms from among the 250 farms evaluated. Multivariate logistic regression analysis revealed that “having more than 1,000 pigs” was the most influential risk factor for IAV-S positivity. Farms affected by reassortant IAV-S had significantly larger pig populations than did those where A(H1N1)pdm09 viruses were isolated, thus suggesting that large, corporate farms serve as sites of reassortment events. Conclusions We demonstrate the asymptomatic circulation of IAV-S in the Vietnamese pig population. Raising a large number of pigs on a farm has the strongest impact on the incidence of subclinical IAV-S infection. Given that only some of the corporate farms surveyed were IAV-S positive, further active monitoring is necessary to identify additional risk factors important in subclinical infection of pigs with IAV-S in Vietnam. Electronic supplementary material The online version of this article (doi:10.1186/s12917-016-0844-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nobuhiro Takemae
- Influenza and Prion Diseases Research Center, National Institute of Animal Health, NARO, Ibaraki, Japan.,Thailand-Japan Zoonotic Diseases Collaboration Center, Bangkok, Thailand
| | - Yugo Shobugawa
- Division of International Health, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
| | - Phuong Thanh Nguyen
- Department of Animal Health, Center for Veterinary Diagnostics, Regional Animal Health Office No. 6, Ho Chi Minh City, Vietnam
| | - Tung Nguyen
- Department of Animal Health, Epidemiology Division, Hanoi, Vietnam
| | - Tien Ngoc Nguyen
- Department of Animal Health, Epidemiology Division, Hanoi, Vietnam
| | - Thanh Long To
- Department of Animal Health, National Centre for Veterinary Diagnostics, Hanoi, Vietnam
| | - Phuong Duy Thai
- Department of Animal Health, Center for Veterinary Diagnostics, Regional Animal Health Office No. 6, Ho Chi Minh City, Vietnam
| | - Tho Dang Nguyen
- Department of Animal Health, National Centre for Veterinary Diagnostics, Hanoi, Vietnam
| | - Duy Thanh Nguyen
- Department of Animal Health, Center for Veterinary Diagnostics, Regional Animal Health Office No. 6, Ho Chi Minh City, Vietnam
| | - Dung Kim Nguyen
- Department of Animal Health, Center for Veterinary Diagnostics, Regional Animal Health Office No. 6, Ho Chi Minh City, Vietnam
| | - Hoa Thi Do
- Department of Animal Health, National Centre for Veterinary Diagnostics, Hanoi, Vietnam
| | - Thi Quynh Anh Le
- Department of Animal Health, Center for Veterinary Diagnostics, Regional Animal Health Office No. 6, Ho Chi Minh City, Vietnam
| | - Phan Truong Hua
- Department of Animal Health, Center for Veterinary Diagnostics, Regional Animal Health Office No. 6, Ho Chi Minh City, Vietnam
| | - Hung Van Vo
- Department of Animal Health, Center for Veterinary Diagnostics, Regional Animal Health Office No. 6, Ho Chi Minh City, Vietnam
| | - Diep Thi Nguyen
- Department of Animal Health, Epidemiology Division, Hanoi, Vietnam
| | - Dang Hoang Nguyen
- Department of Animal Health, National Centre for Veterinary Diagnostics, Hanoi, Vietnam
| | - Yuko Uchida
- Influenza and Prion Diseases Research Center, National Institute of Animal Health, NARO, Ibaraki, Japan.,Thailand-Japan Zoonotic Diseases Collaboration Center, Bangkok, Thailand
| | - Reiko Saito
- Division of International Health, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
| | - Takehiko Saito
- Influenza and Prion Diseases Research Center, National Institute of Animal Health, NARO, Ibaraki, Japan. .,Thailand-Japan Zoonotic Diseases Collaboration Center, Bangkok, Thailand. .,United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan.
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11
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Ma M, Anderson BD, Wang T, Chen Y, Zhang D, Gray GC, Lu J. Serological Evidence and Risk Factors for Swine Influenza Infections among Chinese Swine Workers in Guangdong Province. PLoS One 2015; 10:e0128479. [PMID: 26016740 PMCID: PMC4446356 DOI: 10.1371/journal.pone.0128479] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 04/27/2015] [Indexed: 01/15/2023] Open
Abstract
During July to September 2014, we performed a controlled, cross-sectional, seroepidemiologic study among 203 swine workers and 115 control subjects in Guangdong Province. Sera were tested using a hemagglutination inhibition assay against locally-isolated swine H3N2 and H1N1 viruses and commercially-obtained human influenza viral antigens. We found swine workers had a greater prevalence and odds of seropositivity against the swine H3N2 virus (17.3% vs. 7.0%; adjusted OR, 3.4; 95% CI, 1.1 -10.7). Younger age, self-report of a respiratory illness during the last 12 months, and seropositivity against seasonal H3N2 virus were identified as significant risk factors for seropositivity against swine H3N2 virus. As swine workers in China may be exposed to novel influenza viruses, it seems prudent for China to conduct special surveillance for such viruses among them. It also seems wise to offer such workers seasonal influenza vaccines with a goal to reduce cross-species influenza virus transmission.
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Affiliation(s)
- Mengmeng Ma
- Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Benjamin D. Anderson
- Infectious Diseases Division, Global Health Institute, Duke University, Durham, North Carolina, United States of America
| | - Tao Wang
- Zhongshan Center for Disease Control and Prevention, Zhongshan, Guangdong Province, China
- Zhongshan Institute, School of Public Health, Sun Yat-sen University, Zhongshan, Guangdong Province, China
| | - Yingan Chen
- Guangzhou Baiyun Center for Disease Control and Prevention, Guangzhou, Guangdong Province, China
| | - Dingmei Zhang
- Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong Province, China
- Key Laboratory for Tropical Disease Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong Province, China
| | - Gregory C. Gray
- Infectious Diseases Division, Global Health Institute, Duke University, Durham, North Carolina, United States of America
- * E-mail: (JL); (GCG)
| | - Jiahai Lu
- Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong Province, China
- Zhongshan Institute, School of Public Health, Sun Yat-sen University, Zhongshan, Guangdong Province, China
- Key Laboratory for Tropical Disease Control, Sun Yat-sen University, Ministry of Education, Guangzhou, Guangdong Province, China
- * E-mail: (JL); (GCG)
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12
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Visualizing real-time influenza virus infection, transmission and protection in ferrets. Nat Commun 2015; 6:6378. [PMID: 25744559 PMCID: PMC4366512 DOI: 10.1038/ncomms7378] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 01/23/2015] [Indexed: 11/29/2022] Open
Abstract
Influenza transmission efficiency in ferrets is vital for risk-assessment studies. However, the inability to monitor viral infection and transmission dynamics in real time only provides a glimpse into transmissibility. Here we exploit a replication-competent influenza reporter virus to investigate dynamics of infection/transmission in ferrets. Bioluminescent imaging of ferrets infected with A/California/04/2009 H1N1 virus (CA/09) encoding NanoLuc (NLuc) luciferase provides the first real-time snapshot of influenza infection/transmission. Luminescence in the respiratory tract and in less well-characterized extra-pulmonary sites is observed, and imaging identifies infections in animals that would have otherwise been missed by traditional methods. Finally, the reporter virus significantly increases the speed and sensitivity of virological and serological assays. Thus, bioluminescent imaging of influenza infections rapidly determines intra-host dissemination, inter-host transmission and viral load, revealing infection dynamics and pandemic potential of the virus. These results have important implications for antiviral drug susceptibility, vaccine efficacy, transmissibility and pathogenicity studies. Ferrets are the main animal model used for research on influenza transmission. Here, the authors investigate the dynamics of infection and transmission in ferrets using a replication-competent influenza reporter virus and real-time bioluminescence imaging.
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13
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Powell JD, Dlugolenski D, Nagy T, Gabbard J, Lee C, Tompkins SM, Tripp RA. Polymerase discordance in novel swine influenza H3N2v constellations is tolerated in swine but not human respiratory epithelial cells. PLoS One 2014; 9:e110264. [PMID: 25330303 PMCID: PMC4199677 DOI: 10.1371/journal.pone.0110264] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 09/04/2014] [Indexed: 12/03/2022] Open
Abstract
Swine-origin H3N2v, a variant of H3N2 influenza virus, is a concern for novel reassortment with circulating pandemic H1N1 influenza virus (H1N1pdm09) in swine because this can lead to the emergence of a novel pandemic virus. In this study, the reassortment prevalence of H3N2v with H1N1pdm09 was determined in swine cells. Reassortants evaluated showed that the H1N1pdm09 polymerase (PA) segment occurred within swine H3N2 with ∼80% frequency. The swine H3N2-human H1N1pdm09 PA reassortant (swH3N2-huPA) showed enhanced replication in swine cells, and was the dominant gene constellation. Ferrets infected with swH3N2-huPA had increased lung pathogenicity compared to parent viruses; however, swH3N2-huPA replication in normal human bronchoepithelial cells was attenuated - a feature linked to expression of IFN-β and IFN-λ genes in human but not swine cells. These findings indicate that emergence of novel H3N2v influenza constellations require more than changes in the viral polymerase complex to overcome barriers to cross-species transmission. Additionally, these findings reveal that while the ferret model is highly informative for influenza studies, slight differences in pathogenicity may not necessarily be indicative of human outcomes after infection.
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Affiliation(s)
- Joshua D. Powell
- Department of Infectious Diseases, Animal Health Research Center, University of Georgia, Athens, Georgia, United States of America
| | - Daniel Dlugolenski
- Department of Infectious Diseases, Animal Health Research Center, University of Georgia, Athens, Georgia, United States of America
| | - Tamas Nagy
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, Georgia, United States of America
| | - Jon Gabbard
- Department of Infectious Diseases, Animal Health Research Center, University of Georgia, Athens, Georgia, United States of America
| | - Christopher Lee
- Department of Infectious Diseases, Animal Health Research Center, University of Georgia, Athens, Georgia, United States of America
| | - Stephen M. Tompkins
- Department of Infectious Diseases, Animal Health Research Center, University of Georgia, Athens, Georgia, United States of America
| | - Ralph A. Tripp
- Department of Infectious Diseases, Animal Health Research Center, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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14
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Uddin Khan S, Atanasova KR, Krueger WS, Ramirez A, Gray GC. Epidemiology, geographical distribution, and economic consequences of swine zoonoses: a narrative review. Emerg Microbes Infect 2013; 2:e92. [PMID: 26038451 PMCID: PMC3880873 DOI: 10.1038/emi.2013.87] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 11/22/2013] [Accepted: 11/25/2013] [Indexed: 01/19/2023]
Abstract
We sought to review the epidemiology, international geographical distribution, and economic consequences of selected swine zoonoses. We performed literature searches in two stages. First, we identified the zoonotic pathogens associated with swine. Second, we identified specific swine-associated zoonotic pathogen reports for those pathogens from January 1980 to October 2012. Swine-associated emerging diseases were more prevalent in the countries of North America, South America, and Europe. Multiple factors were associated with the increase of swine zoonoses in humans including: the density of pigs, poor water sources and environmental conditions for swine husbandry, the transmissibility of the pathogen, occupational exposure to pigs, poor human sanitation, and personal hygiene. Swine zoonoses often lead to severe economic consequences related to the threat of novel pathogens to humans, drop in public demand for pork, forced culling of swine herds, and international trade sanctions. Due to the complexity of swine-associated pathogen ecology, designing effective interventions for early detection of disease, their prevention, and mitigation requires an interdisciplinary collaborative “One Health” approach from veterinarians, environmental and public health professionals, and the swine industry.
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Affiliation(s)
- Salah Uddin Khan
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida , Gainesville, FL 32611, USA ; Emerging Pathogens Institute, University of Florida , Gainesville, FL 32611, USA
| | - Kalina R Atanasova
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida , Gainesville, FL 32611, USA ; Emerging Pathogens Institute, University of Florida , Gainesville, FL 32611, USA
| | - Whitney S Krueger
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida , Gainesville, FL 32611, USA ; Emerging Pathogens Institute, University of Florida , Gainesville, FL 32611, USA
| | - Alejandro Ramirez
- Veterinary Diagnosis and Production Animal Medicine, Iowa State University , Iowa, IA 5011, USA
| | - Gregory C Gray
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida , Gainesville, FL 32611, USA ; Emerging Pathogens Institute, University of Florida , Gainesville, FL 32611, USA
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15
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Jhung MA, Epperson S, Biggerstaff M, Allen D, Balish A, Barnes N, Beaudoin A, Berman L, Bidol S, Blanton L, Blythe D, Brammer L, D'Mello T, Danila R, Davis W, de Fijter S, Diorio M, Durand LO, Emery S, Fowler B, Garten R, Grant Y, Greenbaum A, Gubareva L, Havers F, Haupt T, House J, Ibrahim S, Jiang V, Jain S, Jernigan D, Kazmierczak J, Klimov A, Lindstrom S, Longenberger A, Lucas P, Lynfield R, McMorrow M, Moll M, Morin C, Ostroff S, Page SL, Park SY, Peters S, Quinn C, Reed C, Richards S, Scheftel J, Simwale O, Shu B, Soyemi K, Stauffer J, Steffens C, Su S, Torso L, Uyeki TM, Vetter S, Villanueva J, Wong KK, Shaw M, Bresee JS, Cox N, Finelli L. Outbreak of variant influenza A(H3N2) virus in the United States. Clin Infect Dis 2013; 57:1703-12. [PMID: 24065322 PMCID: PMC5733625 DOI: 10.1093/cid/cit649] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Background. Variant influenza virus infections are rare but may have pandemic potential if person-to-person transmission is efficient. We describe the epidemiology of a multistate outbreak of an influenza A(H3N2) variant virus (H3N2v) first identified in 2011. Methods. We identified laboratory-confirmed cases of H3N2v and used a standard case report form to characterize illness and exposures. We considered illness to result from person-to-person H3N2v transmission if swine contact was not identified within 4 days prior to illness onset. Results. From 9 July to 7 September 2012, we identified 306 cases of H3N2v in 10 states. The median age of all patients was 7 years. Commonly reported signs and symptoms included fever (98%), cough (85%), and fatigue (83%). Sixteen patients (5.2%) were hospitalized, and 1 fatal case was identified. The majority of those infected reported agricultural fair attendance (93%) and/or contact with swine (95%) prior to illness. We identified 15 cases of possible person-to-person transmission of H3N2v. Viruses recovered from patients were 93%–100% identical and similar to viruses recovered from previous cases of H3N2v. All H3N2v viruses examined were susceptible to oseltamivir and zanamivir and resistant to adamantane antiviral medications. Conclusions. In a large outbreak of variant influenza, the majority of infected persons reported exposures, suggesting that swine contact at an agricultural fair was a risk for H3N2v infection. We identified limited person-to-person H3N2v virus transmission, but found no evidence of efficient or sustained person-to-person transmission. Fair managers and attendees should be aware of the risk of swine-to-human transmission of influenza viruses in these settings.
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Affiliation(s)
- Michael A Jhung
- Influenza Division, National Center for Immunization and Respiratory Disease
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16
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Karlsson EA, Ciuoderis K, Freiden PJ, Seufzer B, Jones JC, Johnson J, Parra R, Gongora A, Cardenas D, Barajas D, Osorio JE, Schultz-Cherry S. Prevalence and characterization of influenza viruses in diverse species in Los Llanos, Colombia. Emerg Microbes Infect 2013; 2:e20. [PMID: 26038461 PMCID: PMC3636595 DOI: 10.1038/emi.2013.20] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 03/05/2013] [Accepted: 03/11/2013] [Indexed: 11/27/2022]
Abstract
While much is known about the prevalence of influenza viruses in North America and Eurasia, their prevalence in birds and mammals in South America is largely unknown. To fill this knowledge gap and provide a baseline for future ecology and epidemiology studies, we conducted 2 years of influenza surveillance in the eastern plains (Los Llanos) region of Colombia. Real-time reverse transcriptase polymerase chain reaction (RT-PCR) identified influenza viruses in wild birds, domestic poultry, swine and horses. Prevalence ranged from 2.6% to 13.4% across species. Swine showed the highest prevalence and were infected primarily with 2009 pandemic H1N1 (pH1N1) viruses genetically related to those in humans. In addition, we isolated H5N2 viruses from two resident species of whistling ducks (genus Dendrocygna) that differed completely from previous South American isolates, instead genetically resembling North American wild bird viruses. Both strains caused low pathogenicity in chickens and mammals. The prevalence and subtype diversity of influenza viruses isolated from diverse species within a small area of Colombia highlights the need for enhanced surveillance throughout South America, including monitoring of the potential transmissibility of low-pathogenic H5N2 viruses from wild birds to domestic poultry and the emergence of reassortant viruses in domestic swine.
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Affiliation(s)
- Erik A Karlsson
- Department of Infectious Diseases, St Jude Children's Research Hospital , Memphis, TN 38105, USA
| | - Karl Ciuoderis
- Department of Pathobiological Sciences, University of Wisconsin-Madison School of Veterinary Medicine , Madison, WI 53706, USA
| | - Pamela J Freiden
- Department of Infectious Diseases, St Jude Children's Research Hospital , Memphis, TN 38105, USA
| | - Bradley Seufzer
- Department of Infectious Diseases, St Jude Children's Research Hospital , Memphis, TN 38105, USA
| | - Jeremy C Jones
- Department of Infectious Diseases, St Jude Children's Research Hospital , Memphis, TN 38105, USA
| | - Jordan Johnson
- Department of Infectious Diseases, St Jude Children's Research Hospital , Memphis, TN 38105, USA
| | - Rocio Parra
- GIRGA Group, University de los Llanos School of Veterinary Medicine , Villavicencio 500001, Colombia
| | - Agustin Gongora
- GIRGA Group, University de los Llanos School of Veterinary Medicine , Villavicencio 500001, Colombia
| | - Dario Cardenas
- University Cooperativa de Colombia School of Veterinary Medicine , Villavicencio 500001, Colombia
| | - Diana Barajas
- University Cooperativa de Colombia School of Veterinary Medicine , Villavicencio 500001, Colombia
| | - Jorge E Osorio
- Department of Pathobiological Sciences, University of Wisconsin-Madison School of Veterinary Medicine , Madison, WI 53706, USA
| | - Stacey Schultz-Cherry
- Department of Infectious Diseases, St Jude Children's Research Hospital , Memphis, TN 38105, USA
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