A Comprehensive Review on Equine Influenza Virus: Etiology, Epidemiology, Pathobiology, Advances in Developing Diagnostics, Vaccines, and Control Strategies.
Abstract: Among all the emerging and re-emerging animal diseases, influenza group is the prototype member associated with severe respiratory infections in wide host species. Wherein, Equine influenza (EI) is the main cause of respiratory illness in equines across globe and is caused by equine influenza A virus (EIV-A) which has impacted the equine industry internationally due to high morbidity and marginal morality. The virus transmits easily by direct contact and inhalation making its spread global and leaving only limited areas untouched. Hitherto reports confirm that this virus crosses the species barriers and found to affect canines and few other animal species (cat and camel). EIV is continuously evolving with changes at the amino acid level wreaking the control program a tedious task. Until now, no natural EI origin infections have been reported explicitly in humans. Recent advances in the diagnostics have led to efficient surveillance and rapid detection of EIV infections at the onset of outbreaks. Incessant surveillance programs will aid in opting a better control strategy for this virus by updating the circulating vaccine strains. Recurrent vaccination failures against this virus due to antigenic drift and shift have been disappointing, however better understanding of the virus pathogenesis would make it easier to design effective vaccines predominantly targeting the conserved epitopes (HA glycoprotein). Additionally, the cold adapted and canarypox vectored vaccines are proving effective in ceasing the severity of disease. Furthermore, better understanding of its genetics and molecular biology will help in estimating the rate of evolution and occurrence of pandemics in future. Here, we highlight the advances occurred in understanding the etiology, epidemiology and pathobiology of EIV and a special focus is on designing and developing effective diagnostics, vaccines and control strategies for mitigating the emerging menace by EIV.
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
This research provides a comprehensive review on Equine Influenza Virus, its causes, how it spreads, its effects on horses and other animals, advances in identifying and controlling the infection, and further strategies for control and vaccination.
Etiology, Epidemiology, and Pathobiology
Equine influenza (EI) is a significant respiratory illness in horses (equines) and is caused by the Equine Influenza A virus (EIV-A). This disease has high levels of morbidity (illness) and relatively lower levels of mortality (death).
The virus is easily transmitted through direct contact and inhalation, which contributes to its wide-spread occurrence. Notably, the EI virus has affected canines and few other animal species apart from horses.
The continuous evolution of the virus, with changes at the molecular level, makes it difficult to control.
No natural EI-origin infections in humans have been explicitly reported to date.
Advances in Diagnostics
Technological advancements enable efficient surveillance and rapid detection of EIV infections in outbreak scenarios. Regular surveillance programs can lead to an improved control strategy of this virus by updating the circulating vaccine strains accordingly.
Vaccine Development
There have been recurrent vaccination failures against the virus due to antigenic drift and shift—a phenomenon involving changes in the virus that render a vaccine ineffective. Nevertheless, a better understanding of the virus’s pathogenesis may facilitate the design of effective vaccines, targeting the conserved epitopes (a portion of the virus that is recognized by the immune system).
Cold-adapted and canarypox vectored vaccines have shown effectiveness in reducing the seriousness of the disease.
Future Strategies
A better understanding of the virus’s genetics and molecular biology may help predict the rate of evolution and potential for pandemics in the future. The focus is on continuing to design and develop effective diagnostics, vaccines, and control strategies to mitigate the harm caused by the EI virus.
Cite This Article
APA
Singh RK, Dhama K, Karthik K, Khandia R, Munjal A, Khurana SK, Chakraborty S, Malik YS, Virmani N, Singh R, Tripathi BN, Munir M, van der Kolk JH.
(2018).
A Comprehensive Review on Equine Influenza Virus: Etiology, Epidemiology, Pathobiology, Advances in Developing Diagnostics, Vaccines, and Control Strategies.
Front Microbiol, 9, 1941.
https://doi.org/10.3389/fmicb.2018.01941
ICAR-Indian Veterinary Research Institute, Bareilly, India.
Dhama, Kuldeep
Division of Pathology, ICAR-Indian Veterinary Research Institute, Bareilly, India.
Karthik, Kumaragurubaran
Central University Laboratory, Tamil Nadu Veterinary and Animal Sciences University, Chennai, India.
Khandia, Rekha
Department of Biochemistry and Genetics, Barkatullah University, Bhopal, India.
Munjal, Ashok
Department of Biochemistry and Genetics, Barkatullah University, Bhopal, India.
Khurana, Sandip K
National Research Centre on Equines, Hisar, India.
Chakraborty, Sandip
Department of Veterinary Microbiology, College of Veterinary Sciences and Animal Husbandry, West Tripura, India.
Malik, Yashpal S
Division of Biological Standardization, ICAR-Indian Veterinary Research Institute, Bareilly, India.
Virmani, Nitin
National Research Centre on Equines, Hisar, India.
Singh, Rajendra
Division of Pathology, ICAR-Indian Veterinary Research Institute, Bareilly, India.
Tripathi, Bhupendra N
National Research Centre on Equines, Hisar, India.
Munir, Muhammad
Division of Biomedical and Life Sciences, Lancaster University, Lancaster, United Kingdom.
van der Kolk, Johannes H
Division of Clinical Veterinary Medicine, Swiss Institute for Equine Medicine (ISME), Vetsuisse Faculty, University of Bern and Agroscope, Bern, Switzerland.
Alvarez AC, Brunck ME, Boyd V, Lai R, Virtue E, Chen W, Bletchly C, Heine HG, Barnard R. A broad spectrum, one-step reverse-transcription PCR amplification of the neuraminidase gene from multiple subtypes of influenza A virus.. Virol J 2008 Jul 9;5:77.
Baz M, Paskel M, Matsuoka Y, Zengel J, Cheng X, Treanor JJ, Jin H, Subbarao K. A live attenuated equine H3N8 influenza vaccine is highly immunogenic and efficacious in mice and ferrets.. J Virol 2015 Feb;89(3):1652-9.
Bengtsson KL. Matrix M adjuvant technology. in Novel Immune Potentiators and Delivery Technologies for Next Generation Vaccines (Boston, MA: Springer; ), 309–320.
Bernardino PN, Mapes SM, Corbin R, Pusterla N. Pyrosequencing as a fast and reliable tool to determine clade affiliation for equine Influenza A virus.. J Vet Diagn Invest 2016 May 1;28(3):323-326.
Bogerd HP, Skalsky RL, Kennedy EM, Furuse Y, Whisnant AW, Flores O, Schultz KL, Putnam N, Barrows NJ, Sherry B, Scholle F, Garcia-Blanco MA, Griffin DE, Cullen BR. Replication of many human viruses is refractory to inhibition by endogenous cellular microRNAs.. J Virol 2014 Jul;88(14):8065-76.
Breathnach CC, Clark HJ, Clark RC, Olsen CW, Townsend HG, Lunn DP. Immunization with recombinant modified vaccinia Ankara (rMVA) constructs encoding the HA or NP gene protects ponies from equine influenza virus challenge.. Vaccine 2006 Feb 20;24(8):1180-90.
Chambers TM, Balasuriya UBR. Equine influenza virus. in Molecular Detection of Animal Viral Pathogens, ed Liu D. (Boca Raton, FL: CRC Press; ), 383–392.
Chien CY, Xu Y, Xiao R, Aramini JM, Sahasrabudhe PV, Krug RM, Montelione GT. Biophysical characterization of the complex between double-stranded RNA and the N-terminal domain of the NS1 protein from influenza A virus: evidence for a novel RNA-binding mode.. Biochemistry 2004 Feb 24;43(7):1950-62.
Couch RB, Douglas RG, Rossen R, Kasel J. Role of secretory antibody in influenza. in The Secretory Immune System (Washington, DC: U.S. Dept. of Public Health; ), 93–112.
Cullinane AA, Barr B, Bernard W, Duncan JL, Mulcahy G, Smith M. Infectious diseases (chapter 1): equine influenza. in The Equine Manual. 2nd Edn, eds Higgins AJ, Snyder JR (Philadelphia, PA: Elsevier Saunders; ), 13–18.
Daly JM, Blunden AS, Macrae S, Miller J, Bowman SJ, Kolodziejek J, Nowotny N, Smith KC. Transmission of equine influenza virus to English foxhounds.. Emerg Infect Dis 2008 Mar;14(3):461-4.
Dhama K, Chakraborty S, Tiwari R, Verma AK, Saminathan M, Amarpal. A concept paper on novel technologies boosting production and safeguarding health of humans and animals. Res Opin Anim Vet Sci 4, 353–370.
Dhama K, Chakraborty S, Mahima, Wani MY, Verma AK, Deb R, Tiwari R, Kapoor S. Novel and emerging therapies safeguarding health of humans and their companion animals: a review.. Pak J Biol Sci 2013 Feb 1;16(3):101-11.
Dhama K, Karthik K, Khandia R, Munjal A, Tiwari R, Rana R, Khurana SK, Sana Ullah, Khan RU, Alagawany M, Farag MR, Dadar M, Joshi SK. Medicinal and Therapeutic Potential of Herbs and Plant Metabolites / Extracts Countering Viral Pathogens - Current Knowledge and Future Prospects.. Curr Drug Metab 2018;19(3):236-263.
Dhama K, Mahendran M, Gupta PK, Rai A. DNA vaccines and their applications in veterinary practice: current perspectives.. Vet Res Commun 2008 Jun;32(5):341-56.
Easterday BC, Hinshaw VS, Halvorson DA. Influenza. in Diseases of Poultry, 10th Edn., eds. Calnek BW, Barnes HJ, Beard CW, McDougald LR, Saif YM (London: Mosby-Wolfe), 583–605.
Edelman R. An overview of adjuvant use. in Vaccine Adjuvants: Preparation Methods and Research Protocols, Vol. 42 (Totowa, NJ: Humana Press Inc.), 1–27.
Elbadry MA, Merrill MM, Ma MM, Ma MJ, Lu JH, Cao WC, Gray GC. China's great wall, Israel's Bar Lev Line, and passive infectious disease surveillance.. Mil Med Res 2014;1:15.
Elton D, Bruce EA, Bryant N, Wise HM, MacRae S, Rash A, Smith N, Turnbull ML, Medcalf L, Daly JM, Digard P. The genetics of virus particle shape in equine influenza A virus.. Influenza Other Respir Viruses 2013 Dec;7 Suppl 4(Suppl 4):81-9.
Feng KH, Sun M, Iketani S, Holmes EC, Parrish CR. Comparing the functions of equine and canine influenza H3N8 virus PA-X proteins: Suppression of reporter gene expression and modulation of global host gene expression.. Virology 2016 Sep;496:138-146.
Fougerolle S, Legrand L, Lecouturier F, Sailleau C, Paillot R, Hans A, Pronost S. Genetic evolution of equine influenza virus strains (H3N8) isolated in France from 1967 to 2015 and the implications of several potential pathogenic factors.. Virology 2017 May;505:210-217.
Gerber H. Clinical features, sequelae and epidemiology of equine influenza. in Proceedings of the 2nd International Conference on Equine Infectious Diseases, Paris, 1969, New York, 1970, ed Bryans JT (Basel: Karger; ), 63–80.
Gibbs EP, Anderson TC. Equine and canine influenza: a review of current events.. Anim Health Res Rev 2010 Jun;11(1):43-51.
Gora IM, Kwasnik M, Zmudzinski JF, Rozek W. Chorioallantoic membranes of embryonated chicken eggs as an alternative system for isolation of equine influenza virus.. Virol J 2017 Jun 21;14(1):120.
Hayward JJ, Dubovi EJ, Scarlett JM, Janeczko S, Holmes EC, Parrish CR. Microevolution of canine influenza virus in shelters and its molecular epidemiology in the United States.. J Virol 2010 Dec;84(24):12636-45.
Heldens JG, Pouwels HG, Derks CG, Van de Zande SM, Hoeijmakers MJ. The first safe inactivated equine influenza vaccine formulation adjuvanted with ISCOM-Matrix that closes the immunity gap.. Vaccine 2009 Sep 4;27(40):5530-7.
Hemann EA, Kang SM, Legge KL. Protective CD8 T cell-mediated immunity against influenza A virus infection following influenza virus-like particle vaccination.. J Immunol 2013 Sep 1;191(5):2486-94.
Hinshaw VS, Olsen CW, Dybdahl-Sissoko N, Evans D. Apoptosis: a mechanism of cell killing by influenza A and B viruses.. J Virol 1994 Jun;68(6):3667-73.
Jagger BW, Wise HM, Kash JC, Walters KA, Wills NM, Xiao YL, Dunfee RL, Schwartzman LM, Ozinsky A, Bell GL, Dalton RM, Lo A, Efstathiou S, Atkins JF, Firth AE, Taubenberger JK, Digard P. An overlapping protein-coding region in influenza A virus segment 3 modulates the host response.. Science 2012 Jul 13;337(6091):199-204.
Joseph U, Su YC, Vijaykrishna D, Smith GJ. The ecology and adaptive evolution of influenza A interspecies transmission.. Influenza Other Respir Viruses 2017 Jan;11(1):74-84.
Junquera EC, Mateos-Hernández L, de la Fuente J, de la Lastra JM. Recent advances in the development of anti-infective prophylactic and/or therapeutic agents based on Toll-Like Receptor (TLRs).. Recent Pat Antiinfect Drug Discov 2014;9(1):14-24.
Koel BF, Burke DF, Bestebroer TM, van der Vliet S, Zondag GC, Vervaet G, Skepner E, Lewis NS, Spronken MI, Russell CA, Eropkin MY, Hurt AC, Barr IG, de Jong JC, Rimmelzwaan GF, Osterhaus AD, Fouchier RA, Smith DJ. Substitutions near the receptor binding site determine major antigenic change during influenza virus evolution.. Science 2013 Nov 22;342(6161):976-9.
Krumbholz A, Philipps A, Oehring H, Schwarzer K, Eitner A, Wutzler P, Zell R. Current knowledge on PB1-F2 of influenza A viruses.. Med Microbiol Immunol 2011 May;200(2):69-75.
Laabassi F. Epidemiology of equine influenza viruses. in Epidemiology of Communicable and Non-Communicable Diseases–Attributes of Lifestyle and Nature on Humankind, ed Kasenga F (InTech). Available online at: https://www.intechopen.com/books/epidemiology-of-communicable-and-non-communicable-diseases-attributes-of-lifestyle-and-nature-on-humankind/epidemiology-of-equine-influenza-viruses.
Lai AC, Chambers TM, Holland RE Jr, Morley PS, Haines DM, Townsend HG, Barrandeguy M. Diverged evolution of recent equine-2 influenza (H3N8) viruses in the Western Hemisphere.. Arch Virol 2001;146(6):1063-74.
Lamb RA, Lai CJ. Sequence of interrupted and uninterrupted mRNAs and cloned DNA coding for the two overlapping nonstructural proteins of influenza virus.. Cell 1980 Sep;21(2):475-85.
Law J. Influenza in horses. in Report of the Commissioner of Agriculture for the Year 1872, ed Commission of Agriculture (Washington, DC: Government Printing Office; ), 203–248.
Lewis NS, Anderson TK, Kitikoon P, Skepner E, Burke DF, Vincent AL. Substitutions near the hemagglutinin receptor-binding site determine the antigenic evolution of influenza A H3N2 viruses in U.S. swine.. J Virol 2014 May;88(9):4752-63.
Malik YS, Sharma K, Jeena LM, Kumar N, Sircar S, Rajak KK. Toll-like receptors: the innate immune receptors with ingenious anti-viral paradigm. South Asian J. Exp. Biol 3, 207–213.
Mathew T, Dhama K, Pawaiya RVS, Mahendran M. Equine influenza. in Advances in Medical and Veterinary Virology, Immunology, and Epidemiology–Vol. 7: Tropical Viral Diseases of Large Domestic Animals–Part 1, ed Mathew T (West Orange, NJ; United Kingdom: Thajema Publishers; Xlibris Corporation; ), Chapter 133–151.
Mathew T, Mahendran M, Dhama K. Equine influenza (Chapter VII). in Advances in Medical & Veterinary Virology, Immunology and Epidemiology, Vol. 6: Influenza and it's Public Health Significance, eds: Mathew TM, Mathew T (West Orange, NJ: Thajema Publishers; ), 112–129.
McAuley JL, Kedzierska K, Brown LE, Shanks GD. Host Immunological Factors Enhancing Mortality of Young Adults during the 1918 Influenza Pandemic.. Front Immunol 2015;6:419.
McKinstry KK, Dutton RW, Swain SL, Strutt TM. Memory CD4 T cell-mediated immunity against influenza A virus: more than a little helpful.. Arch Immunol Ther Exp (Warsz) 2013 Oct;61(5):341-53.
Meeusen EN, Walker J, Peters A, Pastoret PP, Jungersen G. Current status of veterinary vaccines.. Clin Microbiol Rev 2007 Jul;20(3):489-510, table of contents.
Moattari A, Ashrafi H, Kadivar MR, Kheiri MT, Shahidi M, Arabpour M, Ghanbari A. Antigenic variations of human influenza virus in Shiraz, Iran.. Indian J Med Microbiol 2010 Apr-Jun;28(2):114-9.
Nemoto M, Yamanaka T, Bannai H, Tsujimura K, Kokado H. Complete Genomic Sequences of H3N8 Equine Influenza Virus Strains Used as Vaccine Strains in Japan.. Genome Announc 2018 Mar 22;6(12).
Nemoto M, Yamanaka T, Bannai H, Tsujimura K, Kondo T, Matsumura T. Development of a reverse transcription loop-mediated isothermal amplification assay for H7N7 equine influenza virus.. J Vet Med Sci 2012 Jul;74(7):929-31.
Newton JR, Mumford JA. Equine influenza. in Infectious Diseases of Livestock, Vol. 1, ed Coetzer JAW, Tustin RC (Oxford: Oxford University Press; ), 766–774.
. National Research Central on Equines, Annual Report 2009–2010. NRCE Annual Report (2010). 21 pp. Available online at: http://nrce.gov.in/downloads/NRCE%20Annual%20Report%202009-10.pdf.
OIE. Equine Influenza. Manual of Diagnostic Tests and Vaccines for Terrestrial Animals Chapter 2.5.7 (Paris: Office International Des Epizooties; ), 871–883.
Oishi K, Yamayoshi S, Kawaoka Y. Identification of novel amino acid residues of influenza virus PA-X that are important for PA-X shutoff activity by using yeast.. Virology 2018 Mar;516:71-75.
Ozaki H, Sugita S, Kida H. A rapid and highly sensitive method for diagnosis of equine influenza by antigen detection using immuno-PCR.. Jpn J Vet Res 2001 Feb;48(4):187-95.
Park AW, Daly JM, Lewis NS, Smith DJ, Wood JL, Grenfell BT. Quantifying the impact of immune escape on transmission dynamics of influenza.. Science 2009 Oct 30;326(5953):726-8.
Pavulraj S, Bera BC, Joshi A, Anand T, Virmani M, Vaid RK, Shanmugasundaram K, Gulati BR, Rajukumar K, Singh R, Misri J, Singh RK, Tripathi BN, Virmani N. Pathology of Equine Influenza virus (H3N8) in Murine Model.. PLoS One 2015;10(11):e0143094.
Pecoraro HL, Bennett S, Garretson K, Quintana AM, Lunn KF, Landolt GA. Comparison of the Infectivity and Transmission of Contemporary Canine and Equine H3N8 Influenza Viruses in Dogs.. Vet Med Int 2013;2013:874521.
Prasad M, Lambe UP, Brar B, Shah I, J M, Ranjan K, Rao R, Kumar S, Mahant S, Khurana SK, Iqbal HMN, Dhama K, Misri J, Prasad G. Nanotherapeutics: An insight into healthcare and multi-dimensional applications in medical sector of the modern world.. Biomed Pharmacother 2018 Jan;97:1521-1537.
Radostits OM, Gay CC, Blood DC, Hinchcliff KW. Equine influenza. in Veterinary Medicine, A Text Book of Diseases of Cattle, Sheep, Pigs, Goats and Horses, 9th Edn (New York, NY: Elsevier Saunders; ), 1144–1147.
Rivailler P, Perry IA, Jang Y, Davis CT, Chen LM, Dubovi EJ, Donis RO. Evolution of canine and equine influenza (H3N8) viruses co-circulating between 2005 and 2008.. Virology 2010 Dec 5;408(1):71-9.
Rozek W, Kwasnik M, Zmudzinski JF. Detection of antibodies against equine influenza virus by cell based enzyme-linked immunosorbent assay. Bull. Vet. Inst. Pulawy 55, 569–574.
Short KR, Richard M, Verhagen JH, van Riel D, Schrauwen EJ, van den Brand JM, Mänz B, Bodewes R, Herfst S. One health, multiple challenges: The inter-species transmission of influenza A virus.. One Health 2015 Dec 1;1:1-13.
Solórzano A, Foni E, Córdoba L, Baratelli M, Razzuoli E, Bilato D, Martín del Burgo MÁ, Perlin DS, Martínez J, Martínez-Orellana P, Fraile L, Chiapponi C, Amadori M, del Real G, Montoya M. Cross-Species Infectivity of H3N8 Influenza Virus in an Experimental Infection in Swine.. J Virol 2015 Nov;89(22):11190-202.
Stack JC, Murcia PR, Grenfell BT, Wood JL, Holmes EC. Inferring the inter-host transmission of influenza A virus using patterns of intra-host genetic variation.. Proc Biol Sci 2013 Jan 7;280(1750):20122173.
Su S, Wang L, Fu X, He S, Hong M, Zhou P, Lai A, Gray G, Li S. Equine influenza A(H3N8) virus infection in cats.. Emerg Infect Dis 2014 Dec;20(12):2096-9.
Sylte MJ, Suarez DL. Influenza neuraminidase as a vaccine antigen. in Vaccines for Pandemic Influenza. Current Topics in Microbiology and Immunology, Vol. 333, ed Compans R., Orenstein W. (Berlin; Heidelberg: Springer; ).
Townsend HGG, Cook A, Watts TC. Efficacy of a cold-adapted, modified-live virus influenza vaccine: a double-blind challenge trial. Proc. Am. Assoc. Equine Pract 45, 41–42.
Tu J, Zhou H, Jiang T, Li C, Zhang A, Guo X, Zou W, Chen H, Jin M. Isolation and molecular characterization of equine H3N8 influenza viruses from pigs in China.. Arch Virol 2009;154(5):887-90.
Uppal PK, Yadav MP, Sharma SN. Occurrence of equine influenza outbreaks in India. Indian J. Comp. Microbiol. Immunol. Infect. Dis 8, 91–94.
Van de Walle GR, May MA, Peters ST, Metzger SM, Rosas CT, Osterrieder N. A vectored equine herpesvirus type 1 (EHV-1) vaccine elicits protective immune responses against EHV-1 and H3N8 equine influenza virus.. Vaccine 2010 Jan 22;28(4):1048-55.
Wang C, Wang Q, Hu J, Sun H, Pu J, Liu J, Sun Y. A Multiplex RT-PCR Assay for Detection and Differentiation of Avian-Origin Canine H3N2, Equine-Origin H3N8, Human-Origin H3N2, and H1N1/2009 Canine Influenza Viruses.. PLoS One 2017;12(1):e0170374.
Wise HM, Foeglein A, Sun J, Dalton RM, Patel S, Howard W, Anderson EC, Barclay WS, Digard P. A complicated message: Identification of a novel PB1-related protein translated from influenza A virus segment 2 mRNA.. J Virol 2009 Aug;83(16):8021-31.
Xie T, Anderson BD, Daramragchaa U, Chuluunbaatar M, Gray GC. A Review of Evidence that Equine Influenza Viruses Are Zoonotic.. Pathogens 2016 Jul 12;5(3).
Ye J, Xu Y, Harris J, Sun H, Bowman AS, Cunningham F, Cardona C, Yoon KJ, Slemons RD, Wan XF. Mutation from arginine to lysine at the position 189 of hemagglutinin contributes to the antigenic drift in H3N2 swine influenza viruses.. Virology 2013 Nov;446(1-2):225-9.