Tags

Type your tag names separated by a space and hit enter

Influenza A Viruses of Swine (IAV-S) in Vietnam from 2010 to 2015: Multiple Introductions of A(H1N1)pdm09 Viruses into the Pig Population and Diversifying Genetic Constellations of Enzootic IAV-S.
J Virol 2017; 91(1)JV

Abstract

Active surveillance of influenza A viruses of swine (IAV-S) involving 262 farms and 10 slaughterhouses in seven provinces in northern and southern Vietnam from 2010 to 2015 yielded 388 isolates from 32 farms; these viruses were classified into H1N1, H1N2, and H3N2 subtypes. Whole-genome sequencing followed by phylogenetic analysis revealed that the isolates represented 15 genotypes, according to the genetic constellation of the eight segments. All of the H1N1 viruses were entirely A(H1N1)pdm09 viruses, whereas all of the H1N2 and H3N2 viruses were reassortants among 5 distinct ancestral viruses: H1 and H3 triple-reassortant (TR) IAV-S that originated from North American pre-2009 human seasonal H1, human seasonal H3N2, and A(H1N1)pdm09 viruses. Notably, 93% of the reassortant IAV-S retained M genes that were derived from A(H1N1)pdm09, suggesting some advantage in terms of their host adaptation. Bayesian Markov chain Monte Carlo analysis revealed that multiple introductions of A(H1N1)pdm09 and TR IAV-S into the Vietnamese pig population have driven the genetic diversity of currently circulating Vietnamese IAV-S. In addition, our results indicate that a reassortant IAV-S with human-like H3 and N2 genes and an A(H1N1)pdm09 origin M gene likely caused a human case in Ho Chi Minh City in 2010. Our current findings indicate that human-to-pig transmission as well as cocirculation of different IAV-S have contributed to diversifying the gene constellations of IAV-S in Vietnam.

IMPORTANCE

This comprehensive genetic characterization of 388 influenza A viruses of swine (IAV-S) isolated through active surveillance of Vietnamese pig farms from 2010 through 2015 provides molecular epidemiological insight into the genetic diversification of IAV-S in Vietnam after the emergence of A(H1N1)pdm09 viruses. Multiple reassortments among A(H1N1)pdm09 viruses and enzootic IAV-S yielded 14 genotypes, 9 of which carried novel gene combinations. The reassortants that carried M genes derived from A(H1N1)pdm09 viruses became predominant, replacing those of the IAV-S that had been endemic in Vietnam since 2011. Notably, one of the novel reassortants likely caused a human case in Vietnam. Given that Vietnam is the second-largest pig-producing country in Asia, continued monitoring of IAV-S is highly important from the viewpoints of both the swine industry and human public health.

Authors+Show Affiliations

Division of Transboundary Animal Disease, National Institute of Animal Health, NARO, Tsukuba, Japan. Thailand-Japan Zoonotic Diseases Collaboration Center, Bangkok, Thailand.Division of Transboundary Animal Disease, National Institute of Animal Health, NARO, Tsukuba, Japan.Regional Animal Health Office No. 6, Department of Animal Health, Ho Chi Minh City, Vietnam.Epidemiology Division, Department of Animal Health, Hanoi, Vietnam.Epidemiology Division, Department of Animal Health, Hanoi, Vietnam.National Centre for Veterinary Diagnostics, Department of Animal Health, Hanoi, Vietnam.National Centre for Veterinary Diagnostics, Department of Animal Health, Hanoi, Vietnam.Regional Animal Health Office No. 6, Department of Animal Health, Ho Chi Minh City, Vietnam.Regional Animal Health Office No. 6, Department of Animal Health, Ho Chi Minh City, Vietnam.National Centre for Veterinary Diagnostics, Department of Animal Health, Hanoi, Vietnam.Regional Animal Health Office No. 6, Department of Animal Health, Ho Chi Minh City, Vietnam.Regional Animal Health Office No. 6, Department of Animal Health, Ho Chi Minh City, Vietnam.Regional Animal Health Office No. 6, Department of Animal Health, Ho Chi Minh City, Vietnam.Regional Animal Health Office No. 6, Department of Animal Health, Ho Chi Minh City, Vietnam.Regional Animal Health Office No. 6, Department of Animal Health, Ho Chi Minh City, Vietnam.National Centre for Veterinary Diagnostics, Department of Animal Health, Hanoi, Vietnam.Regional Animal Health Office No. 6, Department of Animal Health, Ho Chi Minh City, Vietnam.Epidemiology Division, Department of Animal Health, Hanoi, Vietnam.Division of Transboundary Animal Disease, National Institute of Animal Health, NARO, Tsukuba, Japan. Thailand-Japan Zoonotic Diseases Collaboration Center, Bangkok, Thailand.Division of Transboundary Animal Disease, National Institute of Animal Health, NARO, Tsukuba, Japan taksaito@affrc.go.jp. Thailand-Japan Zoonotic Diseases Collaboration Center, Bangkok, Thailand. United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan.

Pub Type(s)

Journal Article

Language

eng

PubMed ID

27795418

Citation

Takemae, Nobuhiro, et al. "Influenza a Viruses of Swine (IAV-S) in Vietnam From 2010 to 2015: Multiple Introductions of A(H1N1)pdm09 Viruses Into the Pig Population and Diversifying Genetic Constellations of Enzootic IAV-S." Journal of Virology, vol. 91, no. 1, 2017.
Takemae N, Harada M, Nguyen PT, et al. Influenza A Viruses of Swine (IAV-S) in Vietnam from 2010 to 2015: Multiple Introductions of A(H1N1)pdm09 Viruses into the Pig Population and Diversifying Genetic Constellations of Enzootic IAV-S. J Virol. 2017;91(1).
Takemae, N., Harada, M., Nguyen, P. T., Nguyen, T., Nguyen, T. N., To, T. L., ... Saito, T. (2017). Influenza A Viruses of Swine (IAV-S) in Vietnam from 2010 to 2015: Multiple Introductions of A(H1N1)pdm09 Viruses into the Pig Population and Diversifying Genetic Constellations of Enzootic IAV-S. Journal of Virology, 91(1), doi:10.1128/JVI.01490-16.
Takemae N, et al. Influenza a Viruses of Swine (IAV-S) in Vietnam From 2010 to 2015: Multiple Introductions of A(H1N1)pdm09 Viruses Into the Pig Population and Diversifying Genetic Constellations of Enzootic IAV-S. J Virol. 2017 Jan 1;91(1) PubMed PMID: 27795418.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Influenza A Viruses of Swine (IAV-S) in Vietnam from 2010 to 2015: Multiple Introductions of A(H1N1)pdm09 Viruses into the Pig Population and Diversifying Genetic Constellations of Enzootic IAV-S. AU - Takemae,Nobuhiro, AU - Harada,Michiyo, AU - Nguyen,Phuong Thanh, AU - Nguyen,Tung, AU - Nguyen,Tien Ngoc, AU - To,Thanh Long, AU - Nguyen,Tho Dang, AU - Pham,Vu Phong, AU - Le,Vu Tri, AU - Do,Hoa Thi, AU - Vo,Hung Van, AU - Le,Quang Vinh Tin, AU - Tran,Tan Minh, AU - Nguyen,Thanh Duy, AU - Thai,Phuong Duy, AU - Nguyen,Dang Hoang, AU - Le,Anh Quynh Thi, AU - Nguyen,Diep Thi, AU - Uchida,Yuko, AU - Saito,Takehiko, Y1 - 2016/12/16/ PY - 2016/07/29/received PY - 2016/10/03/accepted PY - 2016/11/1/pubmed PY - 2017/5/16/medline PY - 2016/11/1/entrez KW - Vietnam KW - influenza KW - phylogeny KW - pig KW - reassortment JF - Journal of virology JO - J. Virol. VL - 91 IS - 1 N2 - : Active surveillance of influenza A viruses of swine (IAV-S) involving 262 farms and 10 slaughterhouses in seven provinces in northern and southern Vietnam from 2010 to 2015 yielded 388 isolates from 32 farms; these viruses were classified into H1N1, H1N2, and H3N2 subtypes. Whole-genome sequencing followed by phylogenetic analysis revealed that the isolates represented 15 genotypes, according to the genetic constellation of the eight segments. All of the H1N1 viruses were entirely A(H1N1)pdm09 viruses, whereas all of the H1N2 and H3N2 viruses were reassortants among 5 distinct ancestral viruses: H1 and H3 triple-reassortant (TR) IAV-S that originated from North American pre-2009 human seasonal H1, human seasonal H3N2, and A(H1N1)pdm09 viruses. Notably, 93% of the reassortant IAV-S retained M genes that were derived from A(H1N1)pdm09, suggesting some advantage in terms of their host adaptation. Bayesian Markov chain Monte Carlo analysis revealed that multiple introductions of A(H1N1)pdm09 and TR IAV-S into the Vietnamese pig population have driven the genetic diversity of currently circulating Vietnamese IAV-S. In addition, our results indicate that a reassortant IAV-S with human-like H3 and N2 genes and an A(H1N1)pdm09 origin M gene likely caused a human case in Ho Chi Minh City in 2010. Our current findings indicate that human-to-pig transmission as well as cocirculation of different IAV-S have contributed to diversifying the gene constellations of IAV-S in Vietnam. IMPORTANCE: This comprehensive genetic characterization of 388 influenza A viruses of swine (IAV-S) isolated through active surveillance of Vietnamese pig farms from 2010 through 2015 provides molecular epidemiological insight into the genetic diversification of IAV-S in Vietnam after the emergence of A(H1N1)pdm09 viruses. Multiple reassortments among A(H1N1)pdm09 viruses and enzootic IAV-S yielded 14 genotypes, 9 of which carried novel gene combinations. The reassortants that carried M genes derived from A(H1N1)pdm09 viruses became predominant, replacing those of the IAV-S that had been endemic in Vietnam since 2011. Notably, one of the novel reassortants likely caused a human case in Vietnam. Given that Vietnam is the second-largest pig-producing country in Asia, continued monitoring of IAV-S is highly important from the viewpoints of both the swine industry and human public health. SN - 1098-5514 UR - https://www.unboundmedicine.com/medline/citation/27795418/Influenza_A_Viruses_of_Swine__IAV_S__in_Vietnam_from_2010_to_2015:_Multiple_Introductions_of_A_H1N1_pdm09_Viruses_into_the_Pig_Population_and_Diversifying_Genetic_Constellations_of_Enzootic_IAV_S_ L2 - https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/27795418/ DB - PRIME DP - Unbound Medicine ER -