201
|
Schnitzler SU, Schnitzler P. An update on swine-origin influenza virus A/H1N1: a review. Virus Genes 2009; 39:279-92. [PMID: 19809872 PMCID: PMC7088521 DOI: 10.1007/s11262-009-0404-8] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2009] [Accepted: 09/21/2009] [Indexed: 11/30/2022]
Abstract
Influenza viruses cause annual epidemics and occasional pandemics that have claimed the lives of millions. The emergence of new strains will continue to pose challenges to public health and the scientific communities. The recent flu pandemic caused by a swine-origin influenza virus A/H1N1 (S-OIV) presents an opportunity to examine virulence factors, the spread of the infection and to prepare for major influenza outbreaks in the future. The virus contains a novel constellation of gene segments, the nearest known precursors being viruses found in swine and it probably arose through reassortment of two viruses of swine origin. Specific markers for virulence can be evaluated in the viral genome, PB1-F2 is a molecular marker of pathogenicity but is not present in the new S-OIV. While attention was focused on a threat of an avian influenza H5N1 pandemic emerging from Asia, a novel influenza virus of swine origin emerged in North America, and is now spreading worldwide. However, S-OIV demonstrates that even serotypes already encountered in past human pandemics may constitute new pandemic threats. There are concerns that this virus may mutate or reassort with existing influenza viruses giving rise to more transmissible or more pathogenic viruses. The 1918 Spanish flu pandemic virus was relatively mild in its first wave and acquired more virulence when it returned in the winter. Thus preparedness on a global scale against a potential more virulent strain is highly recommended. Most isolates of the new S-OIVs are susceptible to neuraminidase inhibitors, and currently a vaccine against the pandemic strain is being manufactured and will be available this fall. This review summarizes the current information on the new pandemic swine-origin influenza virus A/H1N1.
Collapse
Affiliation(s)
- Sebastian U. Schnitzler
- Department of Virology, Hygiene Institute, University of Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Paul Schnitzler
- Department of Virology, Hygiene Institute, University of Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| |
Collapse
|
202
|
Acute respiratory distress syndrome induced by H9N2 virus in mice. Arch Virol 2009; 155:187-95. [PMID: 19946715 PMCID: PMC7101852 DOI: 10.1007/s00705-009-0560-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Accepted: 10/29/2009] [Indexed: 01/06/2023]
Abstract
H9N2 avian influenza viruses have repeatedly caused infections in swine and humans in some countries. The purpose of the present study was to evaluate the pulmonary pathology caused by H9N2 viral infection in mice. Six- to eight-week-old BALB/c mice were infected intranasally with 1 × 104 MID50 of A/Chicken/Hebei/4/2008(H9N2) virus. Clinical signs, pathological changes and viral replication in lungs, arterial blood gas, and cytokines in bronchoalveolar lavage fluid (BALF) were observed at different time points after infection. A control group was infected intranasally with noninfectious allantoic fluid. H9N2-infected mice exhibited severe respiratory syndrome, with a mortality rate of 60%. Gross observations showed that infected lungs were highly edematous. Major histopathological changes in infected lungs included diffuse pneumonia and alveolar damage, with neutrophil-dominant inflammatory cellular infiltration, interstitial and alveolar edema, hemorrhage, and severe bronchiolitis/peribronchiolitis. In addition, H9N2 viral infection resulted in severe progressive hypoxemia, lymphopenia, and a significant increase in neutrophils, tumor necrosis factor-α and interleukin-6 in BALF. The features described above satisfy the criteria for acute respiratory distress syndrome (ARDS). Our data show that H9N2 viral infection resulted in ARDS in mice, and this may facilitate studies of the pathogenesis of future potential H9N2 disease in humans.
Collapse
|
203
|
Liu W, Wei MT, Tong Y, Tang F, Zhang L, Fang L, Yang H, Cao WC. Seroprevalence and genetic characteristics of five subtypes of influenza A viruses in the Chinese pig population: a pooled data analysis. Vet J 2009; 187:200-6. [PMID: 19945318 DOI: 10.1016/j.tvjl.2009.10.026] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Revised: 10/22/2009] [Accepted: 10/23/2009] [Indexed: 11/25/2022]
Abstract
A literature review and pooled data analysis were carried out to examine the prevalence of antibodies against five influenza virus subtypes in pigs in China over a 10-year period (1999-2009). The average seropositive frequencies of subtypes H1, H3, H5, H7 and H9 were 3478/11,168 (31.1%), 2900/10,139 (28.6%), 77/5945 (1.3%), 0/1440 (0%) and 86/3619 (2.4%), respectively. There was a geographical variation in the seroprevalence of subtype H1, with the highest seroprevalence in pigs in South and East China. BLAST analysis of genetic sequences revealed that genome segments with moderate homology to the 2009 pandemic influenza A (H1N1) virus were present among swine influenza viruses isolated in China, especially in South and East China. It was concluded from both serological and genetic studies that subtypes H1, H3, H5 and H9 are currently co-circulating in pigs in China, with the H1 subtype most commonly detected, followed by H3.
Collapse
Affiliation(s)
- Wei Liu
- Beijing Institute of Microbiology and Epidemiology, State Key Laboratory of Pathogen and Biosecurity, 100071 Beijing, PR China
| | | | | | | | | | | | | | | |
Collapse
|
204
|
Ge FF, Zhou JP, Liu J, Wang J, Zhang WY, Sheng LP, Xu F, Ju HB, Sun QY, Liu PH. Genetic evolution of H9 subtype influenza viruses from live poultry markets in Shanghai, China. J Clin Microbiol 2009; 47:3294-300. [PMID: 19656985 PMCID: PMC2756938 DOI: 10.1128/jcm.00355-09] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Revised: 05/21/2009] [Accepted: 07/22/2009] [Indexed: 11/20/2022] Open
Abstract
H9N2 influenza viruses have become established and maintain long-term endemicity in poultry. The complete genomes of seven avian H9N2 influenza viruses were characterized. These seven influenza virus isolates were obtained from live poultry markets in Shanghai, China, in 2002 and from 2006 to 2008. Genetic analysis revealed that all seven isolates had an RSSR motif at the cleavage site of hemagglutinin (HA), indicating low pathogenicity in chickens. Phylogenetic analyses indicated that the seven avian H9N2 viruses belonged to the lineage represented by Duck/Hong Kong/Y280/97 (H9N2), a virus belonging to the Chicken/Beijing/1/94-like (H9N2) lineage, and that they are all quadruple reassortants consisting of genes from different lineages. The six internal genes of the isolates possessed H5N1-like sequences, indicating that they were reassortants of H9 and H5 viruses. All of the viruses had nonstructural (as well as HA and neuraminidase) genes derived from the Duck/Hong Kong/Y280/97-like virus lineage but also had other genes of mixed avian virus origin, including genes similar to those of H5N1 viruses (Gs/GD-like). The infected chickens showed no signs of disease. These results show the genetic and biological diversity of H9N2 viruses in Shanghai and support their potential role as pandemic influenza agents.
Collapse
Affiliation(s)
- Fei-Fei Ge
- Shanghai Animal Disease Control Center, Shanghai 201103, People's Republic of China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
205
|
Nicholson KG, Thompson CI, Klap JM, Wood JM, Batham S, Newman RW, Mischler R, Zambon MC, Stephenson I. Safety and immunogenicity of whole-virus, alum-adjuvanted whole-virus, virosomal, and whole-virus intradermal influenza A/H9N2 vaccine formulations. Vaccine 2009; 28:171-8. [PMID: 19799843 DOI: 10.1016/j.vaccine.2009.09.103] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2009] [Revised: 09/15/2009] [Accepted: 09/22/2009] [Indexed: 11/30/2022]
Abstract
Avian influenza H9N2 viruses are considered as a pandemic threat. We assessed the safety and immunogenicity of fourteen H9N2 vaccine formulations. A randomized, phase I trial was done in 353 adults, aged 18-82 years. Subjects received two doses of A/Hong Kong/1073/99 (H9N2) whole-virus, alum-adjuvanted whole-virus, virosomal, or intradermal whole-virus vaccine at four doses (1.7, 5, 15 or 45 microg haemagglutinin). Sera were obtained before and three weeks after each vaccination (days 0, 21, and 42) for haemagglutination-inhibition (HAI) and neutralization assays. All formulations were well tolerated. Pre-vaccination sera from subjects aged below or above 40 years had baseline antibody to H9N2 in 1% and 16% of samples. Compared to intramuscular whole-virus vaccine, alum-adjuvanted vaccine was more immunogenic, intradermal vaccine was comparable, and virosomal vaccine less immunogenic. Among subjects under 40 years, two doses (45, 15, and 5 microg) of alum-adjuvanted vaccine achieved seroprotective HAI titres in 50%, 41%, and 39% respectively, and neutralization seroconversions in 83%, 82%, and 78% of recipients. Among subjects over 40 years, one dose (45, 15, and 5 microg) of alum-adjuvanted vaccine achieved seroprotective HAI titres in 50%, 25% and 0% respectively, and neutralization seroconversions in 88%, 63% and 63% of recipients. Among immunologically naive subjects under 40 years, two doses of vaccine are required and alum-adjuvanted vaccines were most immunogenic. Among immunologically primed subjects over 40 years, one dose of whole-virus or alum-adjuvanted vaccine induced immune responses; the second dose provided less additional benefit. However, no vaccine formulation satisfied all European regulatory criteria for pandemic vaccines.
Collapse
Affiliation(s)
- Karl G Nicholson
- Infectious Diseases Unit, University Hospitals Leicester, Leicester, LE1 5WW, UK.
| | | | | | | | | | | | | | | | | |
Collapse
|
206
|
De Vleeschauwer A, Atanasova K, Van Borm S, van den Berg T, Rasmussen TB, Uttenthal Å, Van Reeth K. Comparative pathogenesis of an avian H5N2 and a swine H1N1 influenza virus in pigs. PLoS One 2009; 4:e6662. [PMID: 19684857 PMCID: PMC2722722 DOI: 10.1371/journal.pone.0006662] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2009] [Accepted: 07/15/2009] [Indexed: 12/21/2022] Open
Abstract
Pigs are considered intermediate hosts for the transmission of avian influenza viruses (AIVs) to humans but the basic organ pathogenesis of AIVs in pigs has been barely studied. We have used 42 four-week-old influenza naive pigs and two different inoculation routes (intranasal and intratracheal) to compare the pathogenesis of a low pathogenic (LP) H5N2 AIV with that of an H1N1 swine influenza virus. The respiratory tract and selected extra-respiratory tissues were examined for virus replication by titration, immunofluorescence and RT-PCR throughout the course of infection. Both viruses caused a productive infection of the entire respiratory tract and epithelial cells in the lungs were the major target. Compared to the swine virus, the AIV produced lower virus titers and fewer antigen positive cells at all levels of the respiratory tract. The respiratory part of the nasal mucosa in particular showed only rare AIV positive cells and this was associated with reduced nasal shedding of the avian compared to the swine virus. The titers and distribution of the AIV varied extremely between individual pigs and were strongly affected by the route of inoculation. Gross lung lesions and clinical signs were milder with the avian than with the swine virus, corresponding with lower viral loads in the lungs. The brainstem was the single extra-respiratory tissue found positive for virus and viral RNA with both viruses. Our data do not reject the theory of the pig as an intermediate host for AIVs, but they suggest that AIVs need to undergo genetic changes to establish full replication potential in pigs. From a biomedical perspective, experimental LP H5 AIV infection of pigs may be useful to examine heterologous protection provided by H5 vaccines or other immunization strategies, as well as for further studies on the molecular pathogenesis and neurotropism of AIVs in mammals.
Collapse
Affiliation(s)
| | - Kalina Atanasova
- Laboratory of Virology, Faculty of Veterinary Medicine Ghent University, Merelbeke, Belgium
| | - Steven Van Borm
- Avian Virology & Immunology, Veterinary & Agrochemical Research Centre, Brussels, Belgium
| | - Thierry van den Berg
- Avian Virology & Immunology, Veterinary & Agrochemical Research Centre, Brussels, Belgium
| | | | - Åse Uttenthal
- National Veterinary Institute, Technical University of Denmark, Kalvehave, Denmark
| | - Kristien Van Reeth
- Laboratory of Virology, Faculty of Veterinary Medicine Ghent University, Merelbeke, Belgium
- * E-mail:
| |
Collapse
|
207
|
Wallensten A. Influenza virus in wild birds and mammals other than man. MICROBIAL ECOLOGY IN HEALTH AND DISEASE 2009. [DOI: 10.1080/08910600701406786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Anders Wallensten
- Smedby Health Center, Kalmar County Council, Kalmar, Sweden
- Division of Molecular Virology, Department of Molecular and Clinical Medicine (IMK), Faculty of Health Sciences, Linköping University, Linköping, Sweden
| |
Collapse
|
208
|
Smith GJD, Vijaykrishna D, Bahl J, Lycett SJ, Worobey M, Pybus OG, Ma SK, Cheung CL, Raghwani J, Bhatt S, Peiris JSM, Guan Y, Rambaut A. Origins and evolutionary genomics of the 2009 swine-origin H1N1 influenza A epidemic. Nature 2009; 459:1122-5. [PMID: 19516283 DOI: 10.1038/nature08182] [Citation(s) in RCA: 1511] [Impact Index Per Article: 100.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2009] [Accepted: 06/04/2009] [Indexed: 12/13/2022]
Abstract
In March and early April 2009, a new swine-origin influenza A (H1N1) virus (S-OIV) emerged in Mexico and the United States. During the first few weeks of surveillance, the virus spread worldwide to 30 countries (as of May 11) by human-to-human transmission, causing the World Health Organization to raise its pandemic alert to level 5 of 6. This virus has the potential to develop into the first influenza pandemic of the twenty-first century. Here we use evolutionary analysis to estimate the timescale of the origins and the early development of the S-OIV epidemic. We show that it was derived from several viruses circulating in swine, and that the initial transmission to humans occurred several months before recognition of the outbreak. A phylogenetic estimate of the gaps in genetic surveillance indicates a long period of unsampled ancestry before the S-OIV outbreak, suggesting that the reassortment of swine lineages may have occurred years before emergence in humans, and that the multiple genetic ancestry of S-OIV is not indicative of an artificial origin. Furthermore, the unsampled history of the epidemic means that the nature and location of the genetically closest swine viruses reveal little about the immediate origin of the epidemic, despite the fact that we included a panel of closely related and previously unpublished swine influenza isolates. Our results highlight the need for systematic surveillance of influenza in swine, and provide evidence that the mixing of new genetic elements in swine can result in the emergence of viruses with pandemic potential in humans.
Collapse
Affiliation(s)
- Gavin J D Smith
- State Key Laboratory of Emerging Infectious Diseases & Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong SAR, China
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
209
|
Qi X, Pang B, Lu CP. Genetic characterization of H1N1 swine influenza A viruses isolated in eastern China. Virus Genes 2009; 39:193-9. [DOI: 10.1007/s11262-009-0375-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Accepted: 05/29/2009] [Indexed: 11/28/2022]
|
210
|
Peiris JSM, Poon LLM, Guan Y. Emergence of a novel swine-origin influenza A virus (S-OIV) H1N1 virus in humans. J Clin Virol 2009; 45:169-73. [PMID: 19540800 DOI: 10.1016/j.jcv.2009.06.006] [Citation(s) in RCA: 214] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Accepted: 06/05/2009] [Indexed: 10/20/2022]
Abstract
A recently emerged novel influenza A H1N1 virus continues to spread globally. The virus contains a novel constellation of gene segments, the nearest known precursors being viruses found in swine and it likely arose through reassortment of two or more viruses of swine origin. H1N1, H1N2 and H3N2 subtype swine influenza viruses have occasionally infected humans before but such zoonotic transmission events did not lead to sustained human-to-human transmission in the manner this swine-origin influenza virus (S-OIV) has done. Its transmission among humans appears to be higher than that observed with seasonal influenza. Children and young adults appear to those most affected and also those who appear to maintain transmission. Clinical disease generally appears mild but complications leading to hospitalization can occur, especially in those with underlying lung or cardiac disease, diabetes or those on immunosuppresive therapies. There are concerns that the virus may reassort with existing human influenza virus giving rise to more transmissible or more pathogenic viruses. The virus appears to retain the potential to transmit back to swine and thus continued reassortment with swine viruses is a cause for concern.
Collapse
Affiliation(s)
- J S Malik Peiris
- State Key Laboratory for Emerging Infectious Disease & Department of Microbiology, The University of Hong Kong, Hong Kong SAR, China.
| | | | | |
Collapse
|
211
|
Takemae N, Parchariyanon S, Damrongwatanapokin S, Uchida Y, Ruttanapumma R, Watanabe C, Yamaguchi S, Saito T. Genetic diversity of swine influenza viruses isolated from pigs during 2000 to 2005 in Thailand. Influenza Other Respir Viruses 2009; 2:181-9. [PMID: 19453423 PMCID: PMC4941901 DOI: 10.1111/j.1750-2659.2008.00062.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Background Recent studies have revealed the existence of genetic diversity in swine influenza viruses (SIVs) in the world. In Thailand, there has been a little information on the molecular characteristics of the SIVs since the first isolation of viruses of H1N1 and H3N2 subtypes in the late 1970s. Our previous study demonstrated that Thai H1N1 SIVs possessed the classical swine H1 and avian‐like swine N1 genes (Takemae et al., Proceedings of the Options for the Control of Influenza VI.2007;350–353). Objectives In the present study, we genetically characterized 12 SIVs including those of H1N1, H1N2 and H3N2 subtypes isolated between 2000 and 2005. Methods We determined the entire nucleotide sequences of the eight gene segments of those isolates. Results Phylogenetic analysis revealed the existence of nine distinct genotypes amongst the Thai SIVs. These genotypes arose from multiple introductions of classical swine, avian‐like swine and human viruses. The existence of two distinct sublineages within classical swine H1 and NS, avian‐like swine PA and M and human H3 and N2 genes of the Thai SIVs suggested that introduction of viruses of classical swine, avian‐like swine and human origins occurred twice respectively into the Thai pig population. The predominance of avian‐like swine genes amongst the Thai SIVs was evident. In particular, three polymerase (PB1, PB2 and PA) and matrix genes of avian‐like swine origin were retained in all the Thai SIVs examined. Conclusions These observations may suggest that genes of avian‐like swine lineages have some advantages to be maintained in pigs as seen in the SIVs established through multiple introductions in other regions.
Collapse
Affiliation(s)
- Nobuhiro Takemae
- Thailand-Japan Zoonotic Diseases Collaboration Center, Bangkok, Thailand
| | | | | | | | | | | | | | | |
Collapse
|
212
|
Yu H, Zhang PC, Zhou YJ, Li GX, Pan J, Yan LP, Shi XX, Liu HL, Tong GZ. Isolation and genetic characterization of avian-like H1N1 and novel ressortant H1N2 influenza viruses from pigs in China. Biochem Biophys Res Commun 2009; 386:278-83. [PMID: 19460353 DOI: 10.1016/j.bbrc.2009.05.056] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2009] [Accepted: 05/14/2009] [Indexed: 12/12/2022]
Abstract
As pigs are susceptible to both human and avian influenza viruses, they have been proposed to be intermediate hosts or mixing vessels for the generation of pandemic influenza viruses through reassortment or adaptation to the mammalian host. In this study, we reported avian-like H1N1 and novel ressortant H1N2 influenza viruses from pigs in China. Homology and phylogenetic analyses showed that the H1N1 virus (A/swine/Zhejiang/1/07) was closely to avian-like H1N1 viruses and seemed to be derived from the European swine H1N1 viruses, which was for the first time reported in China; and the two H1N2 viruses (A/swine/Shanghai/1/07 and A/swine/Guangxi/13/06) were novel ressortant H1N2 influenza viruses containing genes from the classical swine (HA, NP, M and NS), human (NA and PB1) and avian (PB2 and PA) lineages, which indicted that the reassortment among human, avian, and swine influenza viruses had taken place in pigs in China and resulted in the generation of new viruses. The isolation of avian-like H1N1 influenza virus originated from the European swine H1N1 viruses, especially the emergence of two novel ressortant H1N2 influenza viruses provides further evidence that pigs serve as intermediate hosts or "mixing vessels", and swine influenza virus surveillance in China should be given a high priority.
Collapse
Affiliation(s)
- Hai Yu
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai 200241, China
| | | | | | | | | | | | | | | | | |
Collapse
|
213
|
Isolation and genetic characterization of H5N2 influenza viruses from pigs in Korea. J Virol 2009; 83:4205-15. [PMID: 19359528 DOI: 10.1128/jvi.02403-09] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Due to dual susceptibility to both human and avian influenza A viruses, pigs are believed to be effective intermediate hosts for the spread and production of new viruses with pandemic potential. In early 2008, two swine H5N2 viruses were isolated from our routine swine surveillance in Korea. The sequencing and phylogenetic analysis of surface proteins revealed that the Sw/Korea/C12/08 and Sw/Korea/C13/08 viruses were derived from avian influenza viruses of the Eurasian lineage. However, although the Sw/Korea/C12/08 isolate is an entirely avian-like virus, the Sw/Korea/C13/08 isolate is an avian-swine-like reassortant with the PB2, PA, NP, and M genes coming from a 2006 Korean swine H3N1-like virus. The molecular characterization of the two viruses indicated an absence of significant mutations that could be associated with virulence or binding affinity. However, animal experiments showed that the reassortant Sw/Korea/C13/08 virus was more adapted and was more readily transmitted than the purely avian-like virus in a swine experimental model but not in ferrets. Furthermore, seroprevalence in swine sera from 2006 to 2008 suggested that avian H5 viruses have been infecting swine since 2006. Although there are no known potential clinical implications of the avian-swine reassortant virus for pathogenicity in pigs or other species, including humans, at present, the efficient transmissibility of the swine-adapted H5N2 virus could facilitate virus spread and could be a potential model for pandemic, highly pathogenic avian influenza (e.g., H5N1 and H7N7) virus outbreaks or a pandemic strain itself.
Collapse
|
214
|
Abstract
Due to dual susceptibility to both human and avian influenza A viruses, pigs are believed to be effective intermediate hosts for the spread and production of new viruses with pandemic potential. In early 2008, two swine H5N2 viruses were isolated from our routine swine surveillance in Korea. The sequencing and phylogenetic analysis of surface proteins revealed that the Sw/Korea/C12/08 and Sw/Korea/C13/08 viruses were derived from avian influenza viruses of the Eurasian lineage. However, although the Sw/Korea/C12/08 isolate is an entirely avian-like virus, the Sw/Korea/C13/08 isolate is an avian-swine-like reassortant with the PB2, PA, NP, and M genes coming from a 2006 Korean swine H3N1-like virus. The molecular characterization of the two viruses indicated an absence of significant mutations that could be associated with virulence or binding affinity. However, animal experiments showed that the reassortant Sw/Korea/C13/08 virus was more adapted and was more readily transmitted than the purely avian-like virus in a swine experimental model but not in ferrets. Furthermore, seroprevalence in swine sera from 2006 to 2008 suggested that avian H5 viruses have been infecting swine since 2006. Although there are no known potential clinical implications of the avian-swine reassortant virus for pathogenicity in pigs or other species, including humans, at present, the efficient transmissibility of the swine-adapted H5N2 virus could facilitate virus spread and could be a potential model for pandemic, highly pathogenic avian influenza (e.g., H5N1 and H7N7) virus outbreaks or a pandemic strain itself.
Collapse
|
215
|
Pappaioanou M. Highly pathogenic H5N1 avian influenza virus: cause of the next pandemic? Comp Immunol Microbiol Infect Dis 2009; 32:287-300. [PMID: 19318178 DOI: 10.1016/j.cimid.2008.01.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/11/2008] [Indexed: 12/09/2022]
Abstract
Since 1997, when human infections with a highly pathogenic (HP) avian influenza A virus (AIV) subtype H5N1 - previously infecting only birds - were identified in a Hong Kong outbreak, global attention has focused on the potential for this virus to cause the next pandemic. From December 2003, an unprecedented H5N1 epizootic in poultry and migrating wild birds has spread across Asia and into Europe, the Middle East, and Africa. Humans in close contact with sick poultry and on rare occasion with other infected humans, have become infected. As of early March 2007, 12 countries have reported 167 deaths among 277 laboratory-confirmed human infections to WHO. WHO has declared the world to be in Phase 3 of a Pandemic Alert Period. This paper reviews the evolution of HP AIV H5N1, molecular changes that enable AIVs to infect and replicate in human cells and spread efficiently from person-to-person, and strategies to prevent the emergence of a pandemic virus.
Collapse
Affiliation(s)
- Marguerite Pappaioanou
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, 1300 S. Second Street, Suite 300, Minneapolis, MN 55454, USA.
| |
Collapse
|
216
|
Minimal molecular constraints for respiratory droplet transmission of an avian-human H9N2 influenza A virus. Proc Natl Acad Sci U S A 2009; 106:7565-70. [PMID: 19380727 DOI: 10.1073/pnas.0900877106] [Citation(s) in RCA: 182] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Pandemic influenza requires interspecies transmission of an influenza virus with a novel hemagglutinin (HA) subtytpe that can adapt to its new host through either reassortment or point mutations and transmit by aerosolized respiratory droplets. Two previous pandemics of 1957 and 1968 resulted from the reassortment of low pathogenic avian viruses and human subtypes of that period; however, conditions leading to a pandemic virus are still poorly understood. Given the endemic situation of avian H9N2 influenza with human-like receptor specificity in Eurasia and its occasional transmission to humans and pigs, we wanted to determine whether an avian-human H9N2 reassortant could gain respiratory transmission in a mammalian animal model, the ferret. Here we show that following adaptation in the ferret, a reassortant virus carrying the surface proteins of an avian H9N2 in a human H3N2 backbone can transmit efficiently via respiratory droplets, creating a clinical infection similar to human influenza infections. Minimal changes at the protein level were found in this virus capable of respiratory droplet transmission. A reassortant virus expressing only the HA and neuraminidase (NA) of the ferret-adapted virus was able to account for the transmissibility, suggesting that currently circulating avian H9N2 viruses require little adaptation in mammals following acquisition of all human virus internal genes through reassortment. Hemagglutinin inhibition (HI) analysis showed changes in the antigenic profile of the virus, which carries profound implications for vaccine seed stock preparation against avian H9N2 influenza. This report illustrates that aerosolized respiratory transmission is not exclusive to current human H1, H2, and H3 influenza subtypes.
Collapse
|
217
|
Leibler JH, Otte J, Roland-Holst D, Pfeiffer DU, Soares Magalhaes R, Rushton J, Graham JP, Silbergeld EK. Industrial food animal production and global health risks: exploring the ecosystems and economics of avian influenza. ECOHEALTH 2009; 6:58-70. [PMID: 19437076 PMCID: PMC7087879 DOI: 10.1007/s10393-009-0226-0] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2008] [Revised: 01/27/2009] [Accepted: 02/02/2009] [Indexed: 05/26/2023]
Abstract
Many emerging infectious diseases in human populations are associated with zoonotic origins. Attention has often focused on wild animal reservoirs, but most zoonotic pathogens of recent concern to human health either originate in, or are transferred to, human populations from domesticated animals raised for human consumption. Thus, the ecological context of emerging infectious disease comprises two overlapping ecosystems: the natural habitats and populations of wild animals, and the anthropogenically controlled habitats and populations of domesticated species. Intensive food animal production systems and their associated value chains dominate in developed countries and are increasingly important in developing countries. These systems are characterized by large numbers of animals being raised in confinement with high throughput and rapid turnover. Although not typically recognized as such, industrial food animal production generates unique ecosystems -- environments that may facilitate the evolution of zoonotic pathogens and their transmission to human populations. It is often assumed that confined food animal production reduces risks of emerging zoonotic diseases. This article provides evidence suggesting that these industrial systems may increase animal and public health risks unless there is recognition of the specific biosecurity and biocontainment challenges of the industrial model. Moreover, the economic drivers and constraints faced by the industry and its participants must be fully understood in order to inform preventative policy. In order to more effectively reduce zoonotic disease risk from industrial food animal production, private incentives for the implementation of biosecurity must align with public health interests.
Collapse
MESH Headings
- Agricultural Workers' Diseases/epidemiology
- Agricultural Workers' Diseases/prevention & control
- Agricultural Workers' Diseases/virology
- Animal Husbandry/methods
- Animal Husbandry/standards
- Animals
- Animals, Domestic/virology
- Communicable Diseases, Emerging/epidemiology
- Communicable Diseases, Emerging/prevention & control
- Communicable Diseases, Emerging/transmission
- Disease Reservoirs/veterinary
- Ecosystem
- Food Microbiology
- Food-Processing Industry/methods
- Food-Processing Industry/standards
- Global Health
- Humans
- Influenza A Virus, H5N1 Subtype/genetics
- Influenza A Virus, H5N1 Subtype/pathogenicity
- Influenza in Birds/prevention & control
- Influenza in Birds/transmission
- Influenza in Birds/virology
- Influenza, Human/epidemiology
- Influenza, Human/prevention & control
- Influenza, Human/transmission
- Influenza, Human/virology
- Meat Products/virology
- Poultry/virology
- Risk Factors
- Swine/virology
- Zoonoses/transmission
- Zoonoses/virology
Collapse
Affiliation(s)
- Jessica H Leibler
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | | | | | | | | | | | | | | |
Collapse
|
218
|
Further evidence for infection of pigs with human-like H1N1 influenza viruses in China. Virus Res 2009; 140:85-90. [DOI: 10.1016/j.virusres.2008.11.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Revised: 11/06/2008] [Accepted: 11/07/2008] [Indexed: 11/18/2022]
|
219
|
Qi X, Jiao YJ, Pan H, Cui LB, Fan WX, Huang BX, Shi ZY, Wang H. Genetic analysis and rescue of a triple-reassortant H3N2 influenza A virus isolated from swine in eastern China. Virol Sin 2009. [DOI: 10.1007/s12250-009-3006-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
|
220
|
Hickman D, Hossain MJ, Song H, Araya Y, Solórzano A, Perez DR. An avian live attenuated master backbone for potential use in epidemic and pandemic influenza vaccines. J Gen Virol 2009; 89:2682-2690. [PMID: 18931063 PMCID: PMC2886961 DOI: 10.1099/vir.0.2008/004143-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
The unprecedented emergence in Asia of multiple avian influenza virus (AIV) subtypes with a broad host range poses a major challenge in the design of vaccination strategies that are both effective and available in a timely manner. The present study focused on the protective effects of a genetically modified AIV as a source for the preparation of vaccines for epidemic and pandemic influenza. It has previously been demonstrated that a live attenuated AIV based on the internal backbone of influenza A/Guinea fowl/Hong Kong/WF10/99 (H9N2), called WF10att, is effective at protecting poultry species against low- and high-pathogenicity influenza strains. More importantly, this live attenuated virus provided effective protection when administered in ovo. In order to characterize the WF10att backbone further for use in epidemic and pandemic influenza vaccines, this study evaluated its protective effects in mice. Intranasal inoculation of modified attenuated viruses in mice provided adequate protective immunity against homologous lethal challenges with both the wild-type influenza A/WSN/33 (H1N1) and A/Vietnam/1203/04 (H5N1) viruses. Adequate heterotypic immunity was also observed in mice vaccinated with modified attenuated viruses carrying H7N2 surface proteins. The results presented in this report suggest that the internal genes of a genetically modified AIV confer similar protection in a mouse model and thus could be used as a master donor strain for the generation of live attenuated vaccines for epidemic and pandemic influenza.
Collapse
Affiliation(s)
- Danielle Hickman
- Department of Veterinary Medicine, University of Maryland, College Park and Virginia-Maryland Regional College of Veterinary Medicine, 8075 Greenmead Drive, College Park, MD 20742-3711, USA
| | - Md Jaber Hossain
- Department of Veterinary Medicine, University of Maryland, College Park and Virginia-Maryland Regional College of Veterinary Medicine, 8075 Greenmead Drive, College Park, MD 20742-3711, USA
| | - Haichen Song
- Department of Veterinary Medicine, University of Maryland, College Park and Virginia-Maryland Regional College of Veterinary Medicine, 8075 Greenmead Drive, College Park, MD 20742-3711, USA
| | - Yonas Araya
- Department of Veterinary Medicine, University of Maryland, College Park and Virginia-Maryland Regional College of Veterinary Medicine, 8075 Greenmead Drive, College Park, MD 20742-3711, USA
| | - Alicia Solórzano
- Department of Veterinary Medicine, University of Maryland, College Park and Virginia-Maryland Regional College of Veterinary Medicine, 8075 Greenmead Drive, College Park, MD 20742-3711, USA
| | - Daniel R Perez
- Department of Veterinary Medicine, University of Maryland, College Park and Virginia-Maryland Regional College of Veterinary Medicine, 8075 Greenmead Drive, College Park, MD 20742-3711, USA
| |
Collapse
|
221
|
Abstract
Pandemics of influenza emerge from the aquatic bird reservoir, adapt to humans, modify their severity, and cause seasonal influenza. The catastrophic Spanish H1N1 virus may have obtained all of its eight gene segments from the avian reservoir, whereas the Asian H2N2 and the Hong Kong H3N2 pandemics emerged by reassortment between the circulating human virus and an avian H2 or H3 donor. Of the 16 hemagglutinin subtypes, the H2, H5, H6, H7, and H9 viruses are considered to have pandemic potential. While this chapter focuses on the evolution of the Asian highly pathogenic (HP) H5N1 influenza virus, other subtypes are also considered. The unique features of the HP H5N1 viruses that have devastated the domestic poultry of Eurasia are discussed. Although they transmit poorly to humans, they continue to kill more than 60% of infected persons. It is unknown whether HP H5N1 will acquire human pandemic status; if it does not, another subtype eventually will do so, for a future influenza pandemic is inevitable.
Collapse
|
222
|
Sun L, Zhang G, Shu Y, Chen X, Zhu Y, Yang L, Ma G, Kitamura Y, Liu W. Genetic correlation between H3N2 human and swine influenza viruses. J Clin Virol 2008; 44:141-4. [PMID: 19083267 DOI: 10.1016/j.jcv.2008.10.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2008] [Revised: 10/23/2008] [Accepted: 10/24/2008] [Indexed: 11/28/2022]
Abstract
BACKGROUND H3N2 is one of the main subtypes of influenza virus which circulates in human and swine population throughout the world. OBJECTIVES To investigate the genetic correlation between H3N2 human and swine influenza viruses from the same region during the same season. STUDY DESIGN Five H3N2 human and four H3N2 swine influenza viruses were isolated from Guangdong province of China in the winter of 2005. The molecular evolution of eight gene segments was analyzed. RESULTS In the phylogenetic trees of gene segments, all H3N2 human isolates along with the 2000's human isolates formed a cluster, and most of the H3N2 swine isolates along with the 1990's human isolates formed another cluster except that the M and NS gene of A/Swine/Guangdong/01/2005 and the PA gene of A/Swine/Guangdong/02/2005 fell into the cluster of the classical swine influenza virus, indicating the reassortment between H3N2 human and H1N1 swine influenza viruses. CONCLUSIONS In this study, H3N2 swine influenza viruses in 2005 did not originate from the 2000's H3N2 human influenza viruses, but from the 1990's H3N2 human isolates. In addition, the reassortment of H3N2 human and H1N1 swine influenza virus in pigs was common in recent years.
Collapse
Affiliation(s)
- Lei Sun
- Center for Molecular Virology, Institute of Microbiology, Chinese Academy of Sciences, Chaoyang District, Beijing 100101, China
| | | | | | | | | | | | | | | | | |
Collapse
|
223
|
PB2 protein of a highly pathogenic avian influenza virus strain A/chicken/Yamaguchi/7/2004 (H5N1) determines its replication potential in pigs. J Virol 2008; 83:1572-8. [PMID: 19052090 DOI: 10.1128/jvi.01879-08] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
It has been shown that not all but most of the avian influenza viruses replicate in the upper respiratory tract of pigs (H. Kida et al., J. Gen. Virol. 75:2183-2188, 1994). It was shown that A/chicken/Yamaguchi/7/2004 (H5N1) [Ck/Yamaguchi/04 (H5N1)] did not replicate in pigs (N. Isoda et al., Arch. Virol. 151:1267-1279, 2006). In the present study, the genetic basis for this host range restriction was determined using reassortant viruses generated between Ck/Yamaguchi/04 (H5N1) and A/swine/Hokkaido/2/1981 (H1N1) [Sw/Hokkaido/81 (H1N1)]. Two in vivo-generated single-gene reassortant virus clones of the H5N1 subtype (virus clones 1 and 2), whose PB2 gene was of Sw/Hokkaido/81 (H1N1) origin and whose remaining seven genes were of Ck/Yamaguchi/04 (H5N1) origin, were recovered from the experimentally infected pigs. The replicative potential of virus clones 1 and 2 was further confirmed by using reassortant virus (rg-Ck-Sw/PB2) generated by reverse genetics. Interestingly, the PB2 gene of Ck/Yamaguchi/04 (H5N1) did not restrict the replication of Sw/Hokkaido/81 (H1N1), as determined by using reassortant virus rg-Sw-Ck/PB2. The rg-Sw-Ck/PB2 virus replicated to moderate levels and for a shorter duration than parental Sw/Hokkaido/81 (H1N1). Sequencing of two isolates recovered from the pigs inoculated with rg-Sw-Ck/PB2 revealed either the D256G or the E627K amino acid substitution in the PB2 proteins of the isolates. The D256G and E627K mutations enhanced viral polymerase activity in the mammalian cells, correlating with replication of virus in pigs. These results indicate that the PB2 protein restricts the growth of Ck/Yamaguchi/04 (H5N1) in pigs.
Collapse
|
224
|
Zhang P, Tang Y, Liu X, Peng D, Liu W, Liu H, Lu S, Liu X. Characterization of H9N2 influenza viruses isolated from vaccinated flocks in an integrated broiler chicken operation in eastern China during a 5 year period (1998–2002). J Gen Virol 2008; 89:3102-3112. [DOI: 10.1099/vir.0.2008/005652-0] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In the current study, we characterized H9N2 influenza viruses isolated from vaccinated flocks in an integrated broiler chicken operation during a 5 year period (1998–2002). Phylogenetic analysis of the 8 genes of 11 representative viruses showed that they all shared high similarity to that of the first isolate, A/Chicken/Shanghai/F/1998 (Ck/SH/F/98), and clustered to the same lineages. Furthermore, all 11 viruses had a 9 nt deletion between positions 206 and 214 of the neuraminidase gene. These genetic characteristics strongly suggest that these viruses are descendants of the first isolate. In addition, our study also showed that the H9N2 viruses circulating in the operation during this 5 year period were evolving, as shown by antigenic variations between viruses manifested by reactivity with polyclonal antisera and monoclonal antibodies, by haemagglutination with erythrocytes from different animals, by amino acid differences in haemagglutinin and neuraminidase proteins, and by variation in their ability to replicate in the respiratory and intestinal tract and to be transmitted by aerosol. Phylogenetic analysis revealed that the internal genes from some H5N1 viruses of duck origin clustered together with those from H9N2 virus and that the RNP genes of these H5N1 viruses isolated after 2001 are more closely related to the genes of the Ck/SH/F/98-like H9N2 viruses, indicating more recent reassortment events between these two subtypes of viruses. Continuous surveillance of influenza virus in poultry and waterfowl is critical for monitoring the genesis and emergence of potentially pandemic strains in this region.
Collapse
Affiliation(s)
- Pinghu Zhang
- Jiangsu Center for Drug Screening, China Pharmaceutical University, Nanjing 210038, PR China
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, PR China
| | - Yinghua Tang
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, PR China
| | - Xiaowen Liu
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, PR China
| | - Daxin Peng
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, PR China
| | - Wenbo Liu
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, PR China
| | - Hongqi Liu
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, PR China
| | - Shan Lu
- Laboratory of Nucleic Acid Vaccines, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
- China–US Vaccine Research Center, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, PR China
| | - Xiufan Liu
- Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, Yangzhou 225009, PR China
| |
Collapse
|
225
|
Ma W, Kahn RE, Richt JA. The pig as a mixing vessel for influenza viruses: Human and veterinary implications. J Mol Genet Med 2008; 3:158-66. [PMID: 19565018 PMCID: PMC2702078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Revised: 11/05/2008] [Accepted: 11/09/2008] [Indexed: 11/20/2022] Open
Abstract
Influenza A viruses are highly infectious respiratory pathogens that can infect many species. Birds are the reservoir for all known influenza A subtypes; and novel influenza viruses can emerge from birds and infect mammalian species including humans. Because swine are susceptible to infection with both avian and human influenza viruses, novel reassortant influenza viruses can be generated in this mammalian species by reassortment of influenza viral segments leading to the "mixing vessel" theory. There is no direct evidence that the reassortment events culminating in the 1918, 1957 or 1968 pandemic influenza viruses originated from pigs. Genetic reassortment among avian, human and/or swine influenza virus gene segments has occurred in pigs and some novel reassortant swine viruses have been transmitted to humans. Notably, novel reassortant H2N3 influenza viruses isolated from the US pigs, most likely infected with avian influenza viruses through surface water collected in ponds for cleaning barns and watering animals, had a similar genetic make-up to early isolates (1957) of the H2N2 human pandemic. These novel H2N3 swine viruses were able to cause disease in swine and mice and were infectious and highly transmissible in swine and ferrets without prior adaptation. The preceding example shows that pigs could transmit novel viruses from an avian reservoir to other mammalian species. Importantly, H2 viruses pose a substantial risk to humans because they have been absent from mammalian species since 1968 and people born after 1968 have little preexisting immunity to the H2 subtype. It is difficult to predict which virus will cause the next human pandemic and when that pandemic might begin. Importantly, the establishment and spread of a reassorted mammalian-adapted virus from pigs to humans could happen anywhere in the world. Therefore, both human and veterinary research needs to give more attention to potential cross-species transmission capacity of influenza A viruses.
Collapse
Affiliation(s)
- Wenjun Ma
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, 66506, USA
| | - Robert E Kahn
- Avian Flu Action, Warrington, Cheshire, United Kingdom
| | - Juergen A Richt
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, 66506, USA,Correspondence to: Juergen Richt, , Tel: +785 532 2793, Fax: +785 532 4039
| |
Collapse
|
226
|
Okamatsu M, Sakoda Y, Kishida N, Isoda N, Kida H. Antigenic structure of the hemagglutinin of H9N2 influenza viruses. Arch Virol 2008; 153:2189-95. [PMID: 18989614 PMCID: PMC7087127 DOI: 10.1007/s00705-008-0243-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Accepted: 10/10/2008] [Indexed: 11/29/2022]
Abstract
The hemagglutinins (HAs) of H9 influenza viruses isolated from birds and mammals of different species were antigenically and genetically analyzed. Antigenic variants were selected from A/swine/Hong Kong/10/98 (H9N2) and A/duck/Hokkaido/13/00 (H9N2) in the presence of monoclonal antibodies (MAbs). Based on the reactivity patterns of these mutants with a panel of MAbs, at least five non-overlapping antigenic sites were defined using eight MAbs which recognized seven distinct epitopes on the H9 HA molecule. Based on the reactivity patterns with the panel of monoclonal antibodies, 21 H9N2 virus strains isolated from birds and mammals were divided into 7 antigenically distinct groups. The present findings indicate that it is important to monitor the antigenic variation in H9 influenza viruses. The panel of MAbs in the present study, thus, should be useful for detailed antigenic analysis of the H9 HAs for epidemiological studies, the selection of vaccine strains, and diagnosis.
Collapse
Affiliation(s)
- Masatoshi Okamatsu
- Laboratory of Microbiology, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, North 18, West 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan
| | | | | | | | | |
Collapse
|
227
|
Saito T, Suzuki H, Maeda K, Inai K, Takemae N, Uchida Y, Tsunemitsu H. Molecular characterization of an H1N2 swine influenza virus isolated in Miyazaki, Japan, in 2006. J Vet Med Sci 2008; 70:423-7. [PMID: 18460842 DOI: 10.1292/jvms.70.423] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Swine influenza virus (SIV) was isolated from a farm in Miyazaki Prefecture in Japan in July 2006. An isolate was genetically subtyped as H1N2 and was designated A/swine/Miyazaki/1/2006 (H1N2). The nucleotide sequences of all eight viral RNA segments were determined, and then phylogenetic analysis was performed using the neighbor-joining method. All segments were shown to be closely related to those of Japanese SIV H1N2 isolates, which have been circulating since the 1980s. The results indicate the persistence of the SIV H1N2 subtype in the Japanese pig population for more than two decades and emphasize the importance of continuous surveillance for SIV.
Collapse
Affiliation(s)
- Takehiko Saito
- Research Team for Zoonotic Diseases, National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki, Japan.
| | | | | | | | | | | | | |
Collapse
|
228
|
Greger M. The Human/Animal Interface: Emergence and Resurgence of Zoonotic Infectious Diseases. Crit Rev Microbiol 2008; 33:243-99. [DOI: 10.1080/10408410701647594] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
229
|
Hossain MJ, Hickman D, Perez DR. Evidence of expanded host range and mammalian-associated genetic changes in a duck H9N2 influenza virus following adaptation in quail and chickens. PLoS One 2008; 3:e3170. [PMID: 18779858 PMCID: PMC2525835 DOI: 10.1371/journal.pone.0003170] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Accepted: 08/09/2008] [Indexed: 11/20/2022] Open
Abstract
H9N2 avian influenza viruses continue to circulate worldwide; in Asia, H9N2 viruses have caused disease outbreaks and established lineages in land-based poultry. Some H9N2 strains are considered potentially pandemic because they have infected humans causing mild respiratory disease. In addition, some of these H9N2 strains replicate efficiently in mice without prior adaptation suggesting that H9N2 strains are expanding their host range. In order to understand the molecular basis of the interspecies transmission of H9N2 viruses, we adapted in the laboratory a wildtype duck H9N2 virus, influenza A/duck/Hong Kong/702/79 (WT702) virus, in quail and chickens through serial lung passages. We carried out comparative analysis of the replication and transmission in quail and chickens of WT702 and the viruses obtained after 23 serial passages in quail (QA23) followed by 10 serial passages in chickens (QA23CkA10). Although the WT702 virus can replicate and transmit in quail, it replicates poorly and does not transmit in chickens. In contrast, the QA23CkA10 virus was very efficient at replicating and transmitting in quail and chickens. Nucleotide sequence analysis of the QA23 and QA23CkA10 viruses compared to the WT702 virus indicated several nucleotide substitutions resulting in amino acid changes within the surface and internal proteins. In addition, a 21-amino acid deletion was found in the stalk of the NA protein of the QA23 virus and was maintained without further modification in the QA23CkA10 adapted virus. More importantly, both the QA23 and the QA23CkA10 viruses, unlike the WT702 virus, were able to readily infect mice, produce a large-plaque phenotype, showed faster replication kinetics in tissue culture, and resulted in the quick selection of the K627 amino acid mammalian-associated signature in PB2. These results are in agreement with the notion that adaptation of H9 viruses to land-based birds can lead to strains with expanded host range.
Collapse
Affiliation(s)
- Md Jaber Hossain
- Department of Veterinary Medicine, University of Maryland, College Park and Virginia-Maryland Regional College of Veterinary Medicine, College Park, Maryland, United States of America
| | - Danielle Hickman
- Department of Veterinary Medicine, University of Maryland, College Park and Virginia-Maryland Regional College of Veterinary Medicine, College Park, Maryland, United States of America
| | - Daniel R. Perez
- Department of Veterinary Medicine, University of Maryland, College Park and Virginia-Maryland Regional College of Veterinary Medicine, College Park, Maryland, United States of America
- * E-mail:
| |
Collapse
|
230
|
Wan H, Sorrell EM, Song H, Hossain MJ, Ramirez-Nieto G, Monne I, Stevens J, Cattoli G, Capua I, Chen LM, Donis RO, Busch J, Paulson JC, Brockwell C, Webby R, Blanco J, Al-Natour MQ, Perez DR. Replication and transmission of H9N2 influenza viruses in ferrets: evaluation of pandemic potential. PLoS One 2008; 3:e2923. [PMID: 18698430 PMCID: PMC2500216 DOI: 10.1371/journal.pone.0002923] [Citation(s) in RCA: 227] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Accepted: 07/14/2008] [Indexed: 12/04/2022] Open
Abstract
H9N2 avian influenza A viruses are endemic in poultry of many Eurasian countries and have caused repeated human infections in Asia since 1998. To evaluate the potential threat of H9N2 viruses to humans, we investigated the replication and transmission efficiency of H9N2 viruses in the ferret model. Five wild-type (WT) H9N2 viruses, isolated from different avian species from 1988 through 2003, were tested in vivo and found to replicate in ferrets. However these viruses achieved mild peak viral titers in nasal washes when compared to those observed with a human H3N2 virus. Two of these H9N2 viruses transmitted to direct contact ferrets, however no aerosol transmission was detected in the virus displaying the most efficient direct contact transmission. A leucine (Leu) residue at amino acid position 226 in the hemagglutinin (HA) receptor-binding site (RBS), responsible for human virus-like receptor specificity, was found to be important for the transmission of the H9N2 viruses in ferrets. In addition, an H9N2 avian-human reassortant virus, which contains the surface glycoprotein genes from an H9N2 virus and the six internal genes of a human H3N2 virus, showed enhanced replication and efficient transmission to direct contacts. Although no aerosol transmission was observed, the virus replicated in multiple respiratory tissues and induced clinical signs similar to those observed with the parental human H3N2 virus. Our results suggest that the establishment and prevalence of H9N2 viruses in poultry pose a significant threat for humans.
Collapse
Affiliation(s)
- Hongquan Wan
- Department of Veterinary Medicine, University of Maryland, College Park, Maryland, United States of America
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
231
|
Chen HT, Zhang J, Sun DH, Ma LN, Liu XT, Cai XP, Liu YS. Development of reverse transcription loop-mediated isothermal amplification for rapid detection of H9 avian influenza virus. J Virol Methods 2008; 151:200-203. [PMID: 18572258 DOI: 10.1016/j.jviromet.2008.05.009] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 05/04/2008] [Accepted: 05/12/2008] [Indexed: 11/16/2022]
Abstract
Reverse transcription loop-mediated isothermal amplification (RT-LAMP) is a unique gene amplification method that can be completed within 45 min at 63 degrees C. In this study, RT-LAMP was used to develop a rapid and sensitive laboratory diagnostic system for the H9 subtype of avian influenza virus (AIV). The experiment results from the reference strains demonstrated that the established RT-LAMP sensitivity was 10-fold higher than that of RT-PCR, with the detection limit of 10 copies per reaction, and no cross-reactivity was observed from the samples of other related viruses including H5N1, H3N2 subtype of AIV and Newcastle disease virus. Furthermore, a total of 112 clinical samples were tested by RT-LAMP, RT-PCR, and virus isolation, respectively. All of the 85 positive specimens identified by virus isolation were also positive by RT-LAMP, while 7 of these samples were missed by RT-PCR. These results suggest that the present RT-LAMP system may provide a new avenue for the recognition of H9 subtype virus, and may be employed to screen for potential carriers in wild and domestic birds.
Collapse
Affiliation(s)
- Hao-tai Chen
- Key Laboratory of Animal Virology of Ministry of Agriculture, State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, China
| | | | | | | | | | | | | |
Collapse
|
232
|
Amino acid 226 in the hemagglutinin of H4N6 influenza virus determines binding affinity for alpha2,6-linked sialic acid and infectivity levels in primary swine and human respiratory epithelial cells. J Virol 2008; 82:8204-9. [PMID: 18550676 DOI: 10.1128/jvi.00718-08] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Avian lineage H4N6 influenza viruses previously isolated from pigs differ at hemagglutinin amino acids 226 and 228 from H4 subtype viruses isolated from birds. Using a parental H4N6 swine isolate and hemagglutinin mutant viruses (at residues 226 and/or 228), we determined that viruses which contain L226 had a higher affinity for sialic acid alpha2,6 galactose (SAalpha2,6Gal) and a higher infectivity level for primary swine and human respiratory epithelial cells, whereas viruses which contain Q226 had lower SAalpha2,6Gal affinity and lower infectivity levels for both types of cells. Using specific neuraminidases, we found that irrespective of their relative binding preferences, all of the influenza viruses examined utilized SAalpha2,6Gal to infect swine and human cells.
Collapse
|
233
|
Animal health and welfare aspects of avian influenza and the risk of its introduction into the EU poultry holdings - Scientific opinion of the Panel on Animal Health and Welfare. EFSA J 2008. [DOI: 10.2903/j.efsa.2008.715] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
|
234
|
Swine infection with H9N2 influenza viruses in China in 2004. Virus Genes 2008; 36:461-9. [DOI: 10.1007/s11262-008-0227-z] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2007] [Accepted: 03/28/2008] [Indexed: 11/26/2022]
|
235
|
Xing Z, Cardona CJ, Li J, Dao N, Tran T, Andrada J. Modulation of the immune responses in chickens by low-pathogenicity avian influenza virus H9N2. J Gen Virol 2008; 89:1288-1299. [DOI: 10.1099/vir.0.83362-0] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Most low-pathogenicity avian influenza (LPAI) viruses cause no or mild disease in avian species. Little is known about the mechanisms of host defence and the immune responses of avian influenza-infected birds. This study showed that chicken macrophages are susceptible to infection with LPAI H9N2 and H6N2 viruses and that infection led to apoptosis. In H9N2 virus-infected chicken macrophages, Toll-like receptor 7 responded to infection and mediated the cytokine responses. Whilst pro-inflammatory cytokines were largely upregulated, the interferon (IFN) response was fairly weak and IFN-inducible genes were differentially regulated. Among the regulated genes, major histocompatibility complex (MHC) antigens II were downregulated, which also occurred in the lungs of H9N2-infected chickens. Additionally, interleukin (IL)-4, IL-4 receptor and CD74 (MHC class II invariable chain) were also downregulated, all of which are pivotal in the activation of CD4+ helper T cells and humoral immunity. Remarkably, in H9N2 virus-infected chickens, the antibody response was severely suppressed. This was in contrast to the robust antibody response in chickens infected with H6N2 virus, in which expression of MHC class II antigens was upregulated. These data suggest that neutralizing antibodies and humoral immunity may not be developed efficiently in H9N2-infected chickens. These findings raise questions about how some LPAI viruses differentially regulate avian immune responses and whether they have similar effects on mammalian immune function.
Collapse
Affiliation(s)
- Zheng Xing
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Carol J. Cardona
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Jinling Li
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Nguyet Dao
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Tu Tran
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Jason Andrada
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| |
Collapse
|
236
|
Capua I, Alexander DJ. Ecology, epidemiology and human health implications of avian influenza viruses: why do we need to share genetic data? Zoonoses Public Health 2008; 55:2-15. [PMID: 18201321 DOI: 10.1111/j.1863-2378.2007.01081.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Avian influenza (AI) is a listed disease of the World Organisation for Animal Health (OIE) that has become a disease of great importance both for animal and human health. Until recent times, AI was considered a disease of birds with zoonotic implications of limited significance. The emergence and spread of the Asian lineage highly pathogenic AI H5N1 virus has dramatically changed this perspective; not only has it been responsible of the death or culling of millions of birds, but this virus has also been able to infect a variety of non-avian hosts including human beings. The implications of such a panzootic reflect themselves in animal health issues, notably in the reduction of a protein source for developing countries and in the management of the pandemic potential. Retrospective studies have shown that avian progenitors play an important role in the generation of pandemic viruses for humans, and therefore these infections in the avian reservoir should be subjected to control measures aiming at eradication of the Asian H5N1 virus from all sectors rather than just eliminating or reducing the impact of the disease in poultry. Collection and analysis of information in a transparent environment and close collaboration between the medical and veterinary scientific community are crucial to support the global AI crisis.
Collapse
Affiliation(s)
- I Capua
- OIE, FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell'Università 10, 35020 Legnaro, Padova, Italy.
| | | |
Collapse
|
237
|
Draghia-Akli R, Khan AS, Brown PA, Pope MA, Wu L, Hirao L, Weiner DB. Parameters for DNA vaccination using adaptive constant-current electroporation in mouse and pig models. Vaccine 2008; 26:5230-7. [PMID: 18450333 DOI: 10.1016/j.vaccine.2008.03.071] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Enhancing the expression of DNA vaccines requires that specific conditions of delivery are optimized. We describe experiments using adaptive constant-current electroporation (EP) in mice and pigs examining parameters such as target muscle, delay between plasmid delivery and onset of EP pulses and DNA vaccine formulation; our studies show that concentrated formulations result in better expression and immunogenicity. Furthermore, various conditions of EP that limit the amount of muscle damage were measured. The results of these studies will help to advance the success of DNA vaccines in animals into success in human clinical trials.
Collapse
Affiliation(s)
- Ruxandra Draghia-Akli
- VGX Pharmaceuticals, 2700 Research Forest Drive, Suite 180, The Woodlands, TX 77381, United States.
| | | | | | | | | | | | | |
Collapse
|
238
|
Isolation and genetic characterization of avian origin H9N2 influenza viruses from pigs in China. Vet Microbiol 2008; 131:82-92. [PMID: 18403137 DOI: 10.1016/j.vetmic.2008.02.024] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2007] [Revised: 02/23/2008] [Accepted: 02/28/2008] [Indexed: 11/22/2022]
Abstract
As pigs are susceptible to infection with both avian and human influenza A viruses, they have been proposed to be an intermediate host for the adaptation of avian influenza viruses to humans. In April 2006, a disease caused by highly pathogenic porcine reproductive and respiratory syndrome virus (PRRSV) occurred in several pig farms and subsequently overwhelmed almost half of China with more than 2,000,000 cases of pig infection. Here we report a case in which four swine H9N2 influenza viruses were isolated from pigs infected by highly pathogenic PRRSVs in Guangxi province in China. All the eight gene segments of the four swine H9N2 viruses are highly homologous to A/Pigeon/Nanchang/2-0461/00 (H9N2) or A/Wild Duck/Nanchang/2-0480/00 (H9N2). Phylogenetic analyses of eight genes show that the swine H9N2 influenza viruses are of avian origin and may be the descendants of A/Duck/Hong Kong/Y280/97-like viruses. Molecular analysis of the HA gene indicates that our H9N2 isolates might have high-affinity binding to the alpha2,6-NeuAcGal receptor found in human cells. In conclusion, our finding provides further evidence about the interspecies transmission of avian influenza viruses to pigs and emphasizes the importance of reinforcing swine influenza virus (SIV) surveillance, especially after the emergence of highly pathogenic PRRSVs in pigs in China.
Collapse
|
239
|
Genetic evolution of swine influenza A (H3N2) viruses in China from 1970 to 2006. J Clin Microbiol 2008; 46:1067-75. [PMID: 18199784 DOI: 10.1128/jcm.01257-07] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pigs are susceptible to both human and avian influenza viruses and have been proposed to be intermediate hosts, or mixing vessels, for the generation of pandemic influenza viruses through reassortment or adaptation to the mammalian host. In this study, we summarize and report for the first time the coexistence of wholly human-like H3N2 viruses, double-reassortant H3N2 viruses, and triple-reassortant H3N2 viruses in pigs in China by analyzing the eight genes of swine influenza A (H3N2) viruses found in China from 1970 to 2006. In 1970, the first wholly human-like H3N2 (Hong Kong/68-like) viruses were isolated from pigs in Taiwan, and then in the next years Victoria/75-like, Sydney/97-like, New York/99-like, and Moscow/99-like swine H3N2 viruses were regularly isolated in China. In the 1980s, two triple-reassortant viruses were isolated from pigs. Recently, the double-reassortant viruses containing genes from the human (HA and NA) and avian (PB2, PB1, PA, NP, M, and NS) lineages and the triple-reassortant viruses containing genes from the human (HA and NA), classical swine (NP), and avian (PB2, PB1, PA, M, and NS) lineages emerged in pigs in China. The coexistence of wholly human-like and reassortant viruses provides further evidence that pigs serve as intermediate hosts, or mixing vessels, and emphasizes the importance of reinforcing swine influenza virus surveillance in China.
Collapse
|
240
|
Ahn I, Son HS. Comparative study of the hemagglutinin and neuraminidase genes of influenza A virus H3N2, H9N2, and H5N1 subtypes using bioinformatics techniques. Can J Microbiol 2008; 53:830-9. [PMID: 17898838 DOI: 10.1139/w07-044] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To investigate the genomic patterns of influenza A virus subtypes, such as H3N2, H9N2, and H5N1, we collected 1842 sequences of the hemagglutinin and neuraminidase genes from the NCBI database and parsed them into 7 categories: accession number, host species, sampling year, country, subtype, gene name, and sequence. The sequences that were isolated from the human, avian, and swine populations were extracted and stored in a MySQL database for intensive analysis. The GC content and relative synonymous codon usage (RSCU) values were calculated using JAVA codes. As a result, correspondence analysis of the RSCU values yielded the unique codon usage pattern (CUP) of each subtype and revealed no extreme differences among the human, avian, and swine isolates. H5N1 subtype viruses exhibited little variation in CUPs compared with other subtypes, suggesting that the H5N1 CUP has not yet undergone significant changes within each host species. Moreover, some observations may be relevant to CUP variation that has occurred over time among the H3N2 subtype viruses isolated from humans. All the sequences were divided into 3 groups over time, and each group seemed to have preferred synonymous codon patterns for each amino acid, especially for arginine, glycine, leucine, and valine. The bioinformatics technique we introduce in this study may be useful in predicting the evolutionary patterns of pandemic viruses.
Collapse
Affiliation(s)
- Insung Ahn
- Bioinformatics Team, Supercomputing Center, Korea Institute of Science and Technology Information, P.O. Box 122, Yusong-Gu, Daejon 305-806, Korea
| | | |
Collapse
|
241
|
Xu XJ, Xu GY, Zhou HB, Yu ZJ, Zhang AD, Song YF, Jin ML, Chen HC. Evolutionary characterization of influenza virus A/duck/Hubei/W1/2004 (H9N2) isolated from central China. Virus Genes 2007; 36:79-83. [PMID: 18027082 DOI: 10.1007/s11262-007-0123-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Accepted: 05/24/2007] [Indexed: 11/25/2022]
Abstract
Full-length eight gene segments of avian influenza virus A/duck/Hubei/W1/2004(H9N2) (Dk/Hub/W1/04) were amplified by RT-PCR and completely sequenced. Phylogenetic analysis revealed that Dk/Hub/W1/04 was derived from A/Duck/HongKong/Y280/97, not displaying direct evolutional relationship with A/Quail/HongKong/G1/97 or Hubei H5N1 viruses. Meanwhile, Dk/Hub/W1/04 was found highly related to recent three chicken isolates. The connecting peptide of HA and the deletion in NA stalk were consistent with three chicken isolates, and the number of potential glycosylation site on the HA and NA also was similar or identical to the three chicken isolates. These findings suggested that Dk/Hub/W1/04 is likely to transmit back to ducks from chickens.
Collapse
Affiliation(s)
- Xiao-Juan Xu
- Division of Animal Infectious Diseases, National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, PR China
| | | | | | | | | | | | | | | |
Collapse
|
242
|
Abstract
Avian influenza (AI) is a listed disease of the World Organisation for Animal Health (OIE) that has become a disease of great importance both for animal and human health. Until recent times, AI was considered a disease of birds with zoonotic implications of limited significance. The emergence and spread of the Asian lineage highly pathogenic AI (HPAI) H5N1 virus has dramatically changed this perspective; not only has it been responsible of the death or culling of millions of birds, but this virus has also been able to infect a variety of non-avian hosts including human beings. The implications of such a panzootic reflect themselves in animal health issues, notably in the reduction of a protein source for developing countries and in the management of the pandemic potential. Retrospective studies have shown that avian progenitors play an important role in the generation of pandemic viruses for humans, and therefore these infections in the avian reservoir should be subjected to control measures aiming at eradication of the Asian H5N1 virus from all sectors rather than just eliminating or reducing the impact of the disease in poultry.
Collapse
Affiliation(s)
- Ilaria Capua
- OIE, FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell'Università 10, Legnaro, Padova, 35020, Italy.
| | | |
Collapse
|
243
|
Landolt GA, Olsen CW. Up to new tricks - a review of cross-species transmission of influenza A viruses. Anim Health Res Rev 2007; 8:1-21. [PMID: 17692139 DOI: 10.1017/s1466252307001272] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Influenza is a highly contagious disease that has burdened both humans and animals since ancient times. In humans, the most dramatic consequences of influenza are associated with periodically occurring pandemics. Pandemics require the emergence of an antigenically novel virus to which the majority of the population lacks protective immunity. Historically, influenza A viruses from animals have contributed to the generation of human pandemic viruses and they may do so again in the future. It is, therefore, critical to understand the epidemiological and molecular mechanisms that allow influenza A viruses to cross species barriers. This review summarizes the current knowledge of influenza ecology, and the viral factors that are thought to determine influenza A virus species specificity.
Collapse
Affiliation(s)
- Gabriele A Landolt
- Department of Clinical Sciences, Colorado State University, 300 West Drake Road, Fort Collins, CO 80523, USA.
| | | |
Collapse
|
244
|
|
245
|
Xu KM, Smith GJD, Bahl J, Duan L, Tai H, Vijaykrishna D, Wang J, Zhang JX, Li KS, Fan XH, Webster RG, Chen H, Peiris JSM, Guan Y. The genesis and evolution of H9N2 influenza viruses in poultry from southern China, 2000 to 2005. J Virol 2007; 81:10389-401. [PMID: 17652402 PMCID: PMC2045440 DOI: 10.1128/jvi.00979-07] [Citation(s) in RCA: 203] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
H9N2 influenza viruses have become established in terrestrial poultry in different Asian countries over the last 2 decades. Our previous study demonstrated that quail harbor increasingly diverse novel H9N2 reassortants, including both Chicken/Beijing/1/94 (Ck/Bei-like) and Quail/Hong Kong/G1/97 (G1-like) viruses. However, since 1999, the genesis and evolution of H9N2 viruses in different types of poultry have not been investigated systematically. In the present study, H9N2 viruses isolated from chickens, ducks, and other minor poultry species were characterized genetically and antigenically. Our findings demonstrate that Ck/Bei-like H9N2 viruses have been introduced into many different types of poultry in southern China, including quail, partridges, chukar, pheasant, guinea fowl, and domestic ducks, while G1-like viruses were commonly detected in quail, less frequently detected in other minor poultry species, and not detected in chickens and ducks. Genetic analysis revealed 35 genotypes of H9N2 viruses, including 14 novel genotypes that have not been recognized before. Our results also suggested that two-way interspecies transmission exists between different types of poultry. Our study demonstrates that the long-term cocirculation of multiple virus lineages (e.g., H5N1 and H9N2 viruses) in different types of poultry has facilitated the frequent reassortment events that are mostly responsible for the current great genetic diversity in H9N2 and H5N1 influenza viruses in this region. This situation favors the emergence of influenza viruses with pandemic potential.
Collapse
Affiliation(s)
- K M Xu
- International Institute of Infection and Immunity, Shantou University, Guangdong, China, and Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
246
|
Abstract
Pandemic influenza remains a serious public health threat and the processes involved in the evolutionary emergence of pandemic influenza strains remain incompletely understood. Here, we develop a stochastic model for the evolutionary emergence of pandemic influenza, and use it to address three main questions. (i) What is the minimum annual number of avian influenza virus infections required in humans to explain the historical rate of pandemic emergence? (ii) Are such avian influenza infections in humans more likely to give rise to pandemic strains if they are driven by repeated cross-species introductions, or by low-level transmission of avian influenza viruses between humans? (iii) What are the most effective interventions for reducing the probability that an influenza strain with pandemic potential will evolve? Our results suggest that if evolutionary emergence of past pandemics has occurred primarily through viral reassortment in humans, then thousands of avian influenza virus infections in humans must have occurred each year for the past 250 years. Analyses also show that if there is epidemiologically significant variation among avian influenza virus genotypes, then avian virus outbreaks stemming from repeated cross-species transmission events result in a greater likelihood of a pandemic strain evolving than those caused by low-level transmission between humans. Finally, public health interventions aimed at reducing the duration of avian virus infections in humans give the greatest reduction in the probability that a pandemic strain will evolve.
Collapse
Affiliation(s)
- Troy Day
- Department of Mathematics and Statistics, Queen's University, Kingston, Ontario, Canada.
| | | | | |
Collapse
|
247
|
Cong YL, Pu J, Liu QF, Wang S, Zhang GZ, Zhang XL, Fan WX, Brown EG, Liu JH. Antigenic and genetic characterization of H9N2 swine influenza viruses in China. J Gen Virol 2007; 88:2035-2041. [PMID: 17554038 DOI: 10.1099/vir.0.82783-0] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
As pigs are susceptible to infection with both avian and human influenza A viruses, they have been proposed to be an intermediate host for the generation of pandemic virus through reassortment. Antigenic and genetic characterization was performed for five swine H9N2 influenza viruses isolated from diseased pigs from different farms. The haemagglutinin (HA) antigenicity of swine H9N2 viruses was different from that of chicken H9N2 viruses prevalent in northern China. Genetic analysis revealed that all five isolates had an RLSR motif at the cleavage site of HA, which was different from those of A/duck/Hong Kong/Y280/97 (Dk/HK/Y280/97)-like viruses established in chickens in China. Phylogenetic analyses indicated that the five swine H9N2 viruses formed novel HA and neuraminidase sublineages that were related closely to those of earlier chicken H9 viruses and were also consistent with the extent of the observed antigenic variation. The six internal genes of the isolates possessed H5N1-like sequences, indicating that they were reassortants of H9 and H5 viruses. The present results indicate that avian to porcine interspecies transmission of H9N2 viruses might have resulted in the generation of viruses with novel antigenic and genetic characteristics; therefore, surveillance of swine influenza should be given a high priority.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Antigens, Viral/genetics
- Chickens/virology
- China
- Hemagglutinin Glycoproteins, Influenza Virus/genetics
- Hemagglutinin Glycoproteins, Influenza Virus/immunology
- Humans
- Influenza A Virus, H9N2 Subtype/classification
- Influenza A Virus, H9N2 Subtype/genetics
- Influenza A Virus, H9N2 Subtype/immunology
- Influenza A Virus, H9N2 Subtype/isolation & purification
- Influenza in Birds/transmission
- Influenza in Birds/virology
- Influenza, Human/transmission
- Influenza, Human/virology
- Molecular Sequence Data
- Orthomyxoviridae Infections/transmission
- Orthomyxoviridae Infections/veterinary
- Orthomyxoviridae Infections/virology
- Phylogeny
- Reassortant Viruses/classification
- Reassortant Viruses/genetics
- Reassortant Viruses/immunology
- Reassortant Viruses/isolation & purification
- Sequence Homology, Amino Acid
- Sus scrofa/virology
- Swine
- Swine Diseases/transmission
- Swine Diseases/virology
- Zoonoses/transmission
- Zoonoses/virology
Collapse
Affiliation(s)
- Yan L Cong
- Laboratory of Infectious Diseases, College of Veterinary Medicine, State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100094, PR China
| | - Juan Pu
- Laboratory of Infectious Diseases, College of Veterinary Medicine, State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100094, PR China
| | - Qin F Liu
- Laboratory of Infectious Diseases, College of Veterinary Medicine, State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100094, PR China
| | - Shuai Wang
- Laboratory of Infectious Diseases, College of Veterinary Medicine, State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100094, PR China
| | - Guo Z Zhang
- Laboratory of Infectious Diseases, College of Veterinary Medicine, State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100094, PR China
| | - Xing L Zhang
- Laboratory of Infectious Diseases, College of Veterinary Medicine, State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100094, PR China
| | - Wei X Fan
- China Animal Health and Epidemiology Center, Qingdao 266032, PR China
| | - Earl G Brown
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, ON, Canada
| | - Jin H Liu
- Laboratory of Infectious Diseases, College of Veterinary Medicine, State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100094, PR China
| |
Collapse
|
248
|
Abstract
Highly pathogenic avian influenza has not been reported in Nepal to date. Surveillance for the presence of avian influenza viruses was conducted in 16 districts of Nepal from February 2004 to December 2005. Four hundred forty-six serum samples were collected from ducks, chickens, and pigeons and tested for antibodies to all influenza A viruses by competitive enzyme-linked immunosorbent assay (C-ELISA). Any sera positive by C-ELISA were tested for antibodies to H5, H7, and H9 influenza viruses by hemagglutination inhibition tests. One hundred and thirty-five cloacal swabs from healthy ducks and chickens were tested by commercial avian influenza antigen detection kits. A further 13 tissue samples from diseased birds were tested for the presence of virus by virus isolation in eggs, cell culture, and immunohistochemistry. No influenza viruses were detected in any of the tissues or swabs. All serum samples collected before October 2005 were negative for antibodies. The first sera positive for antibodies were collected on October 13, 2005, which were determined to be of the H9N2 subtype. This is the first report of serologic evidence of an avian influenza virus infection in Nepal.
Collapse
Affiliation(s)
- Ganesh R Pant
- Central Veterinary Laboratory, Tripureshwor, Kathmandu, Nepal
| | | |
Collapse
|
249
|
Nili H, Asasi K, Dadras H, Ebrahimi SM, Ebrahimi M. Pathobiology of H9N2 avian influenza virus in Japanese quail (Coturnix coturnix japonica). Avian Dis 2007; 51:390-2. [PMID: 17494591 DOI: 10.1637/7550-033106r1.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Clinical signs, serologic response, viral contents of the trachea and intestine, and histopathological and ultrastructural changes of the tracheal epithelium of Japanese quail experimentally infected with field isolate of H9N2 avian influenza were studied. Vaccinated and unvaccinated quail were inoculated with 10(6.3) 50% embryo infectious dose/bird of A/ chicken/Iran/SH-110/99 (H9N2) virus via nasal inoculation. Clinical signs such as depression, ruffled feathers, diarrhea, and nasal and eye discharges were observed 6 days postinfection (PI). No mortality was observed; however, there was reduction in feed and water consumption and egg production. However, the serologic response of vaccinated challenged and unvaccinated challenged birds was not significantly different. Unvaccinated challenged quail showed more severe histopathologic reaction in their lungs and trachea. Hyperemia, edema, infiltration of inflammatory cells, and deciliation and sloughing of the tracheal epithelium were observed. Ultrastructural study showed dilatation of endoplasmic reticulum and degeneration of Golgi apparatus and cilia of the tracheal lining cells of respiratory epithelium.
Collapse
Affiliation(s)
- H Nili
- Department of Avian Medicine, School of Veterinary Medicine, Shiraz University, P.O. Box 1731, Shiraz 71345, Iran
| | | | | | | | | |
Collapse
|
250
|
Wan H, Perez DR. Amino acid 226 in the hemagglutinin of H9N2 influenza viruses determines cell tropism and replication in human airway epithelial cells. J Virol 2007; 81:5181-91. [PMID: 17344280 PMCID: PMC1900221 DOI: 10.1128/jvi.02827-06] [Citation(s) in RCA: 219] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Accepted: 03/01/2007] [Indexed: 11/20/2022] Open
Abstract
Influenza A viruses of the H9N2 subtype are endemic in poultry in many Eurasian countries and have occasionally caused clinical respiratory diseases in humans. While some avian H9N2 viruses have glutamine (Q) at amino acid position 226 of the hemagglutinin (HA) receptor-binding site, an increasing number of isolates have leucine (L) at this position, which has been associated with the establishment of stable lineages of the H2 and H3 subtypes of viruses in humans. Little is known about the importance of this molecular trait in the infection of H9N2 viruses in humans. We show here that during the course of a single cycle of infection in human airway epithelial (HAE) cells cultured in vitro, the L-226-containing H9N2 viruses displayed human virus-like cell tropisms (preferentially infecting nonciliated cells) different from the tropisms showed by Q-226-containing H9N2 isolates (which infect both ciliated and nonciliated cells at ratios of 1:1 to 3:2) or other waterfowl viruses (which preferentially infect ciliated cells). During multiple cycles of replication in HAE cultures, L-226-containing H9N2 isolates grew consistently more efficiently and reached approximately 100-fold-higher peak titers than those containing Q-226, although peak titers were significantly lower than those induced by human H3N2 viruses. Our results suggest that the variation in residue 226 in the HA affects both cell tropism and replication of H9N2 viruses in HAE cells and may have implications for the abilities of these viruses to infect humans.
Collapse
Affiliation(s)
- Hongquan Wan
- Department of Veterinary Medicine, University of Maryland, College Park, 8075 Greenmead Drive, College Park, MD 20742, USA
| | | |
Collapse
|