Table 1.
The account of vaccination strategies in-use for Equine influenza worldwide.
| S. No. | Vaccine type | Specific note | Study outcome | Antigen used in vaccine | Name of vaccine | Model organism | Reference(s) |
|---|---|---|---|---|---|---|---|
| 1. | Killed vaccine adjuvanted with ISCOM-matrix | Strong antibody response with elevated levels of IFN-γ | ISCOMatrix second generation adjuvant helps to raise primary antibody titer to a value that is sufficient to prevent infection until the time of annual revaccination 12 months later | Purified HA and NA proteins of equine influenza virus strain A/equi-1/Prague/56(H7N7), A/equi2/Newmarket-1/93 (H3N8-American type strain) and A/equi-2/Newmarket-2/93 (H3N8-European type strain) + tetanus toxoi. | Prequenza Te | Fjord horse (n = 12) | Heldens et al., 2009 |
| A significant reduction of virus in excreta and reduction in virus induced pyrexia | |||||||
| 2. | ISCOM-based EI vaccine | Vaccinated and infected animals may be a source of infection by EIV shedding | Vaccinated and infected horse may shed virus and able to infect commingling sentinels. The virus shedding by comminglings is detectable upto 6 days after commingling | Antigens from the strains A/eq1/Newmarket/77 (H7N7), A/eq/Borlange/91 (H3N8, European lineage) and A/eq/Kentucky/98 (H3N8, American lineage). | Equip™ FT | Pony (n = 7) | Paillot et al., 2013b |
| 3. | Cold adapted and pox-vectored | Mimic natural infection by generating both humoral and cellular response | Vaccinated ponies produced high amount of anti-influenza virus IgGa and IgGb antibodies and in statistically significant manner protected from clinical signs of disease | Two live recombinant canarypox viruses expressing the HA of A/eq/KY/94 (American lineage) and A/eq/NM/2/93 (Eurasian lineage), respectively | RECOMBITEK | Ponies (n = 43) | Soboll et al., 2010 |
| 4. | Inactivated equine influenza virus vaccine + equine herpes virus | EIV and EHV-1/4 combination increased antibody response to EIV and did not compromise the humoral immune response to EHV-1/4. | After booster dose there was no significant difference in antibody titer between the EIV only vaccine or EIV + Herpes virus vaccine | A/eq/1/Prague/56 (H7N7) + A/eq/Suffolk/89 (H3N8-European lineage) + A/eq/Newmarket/1/93 (H3N8-American lineage) + inactivated EHV-1 strain 438/77 and EHV-4 strain 405/76. | EIV vaccine Duvaxyn IE + bivalent Duvaxyn EHV-1,4 | Horse (n = 30) | Gildea et al., 2016 |
| 5. | Modified-live cold-adapted A2 strain (Intranasal immunization) | No reversion to virulence strain | The vaccine provided protection form clinical EIV infection caused by Equine-2 influenza viruses (American lineage) and A/equine-2/Saskatoon/90 (Eurasian' lineage) | A/eq/Kentucky/1/91 (H3N8) | Flu Avert IN | Ponies (n = 16) | Chambers et al., 2001; Townsend et al., 2001 |
| 6. | Canary pox vectored vaccines (Intranasal immunization) | Generate colostral antibodies so used during gestation period. The recombinant virus cause an abortive infection in mammalian cells, therefore no progeny viruses are made however viral proteins are expressed, processed endogenously and presented by MHC class I molecules | Meets OIE recommendations for updated EI vaccine and significant protection in vaccinated ponies was observed in comparison to control | A/eq/Richmond/1/07 isolate (Florida clade 2 sub-lineage) + A/eq/Ohio/03 (Florida clade 1 sub-lineage), vectored with canarypox | ProteqFlu | Pony (n = 14) | Paillot et al., 2014 |
| 7. | Equine herpes virus-1 based live vaccine (Carrying H3 gene) | Robust protective immunity against VA05 and NY-99 strains | Elicited a long lasting serological response against both EHV-1 and EIV | Codon-optimized H3 sequence from A/equine/OH/03 | — | Horse (n = 12) | Van de Walle et al., 2010 |
| 8. | Live attenuated reverse genetics based vaccine | A single dose of the vaccine was highly immunogenic and efficacious against wild type virus challenge | Prevent from heterologous challenge | Virus backbone from cold adapted strain A/Ann Arbor/6/60 and HA and NA genes from eq/GA/81 (H3N8) | — | Ferrets and Mice (n = not provided in manuscript) | Baz et al., 2015 |
| 9. | DNA vaccines (containing HA gene) | Cellular and humoral immunity with IgG production, but not IgA | Generation of virus-specific IgGa, IgGb and IFN-γ responses | HA gene of A/Equine/Kentucky/1/81 (Eq/Ky) cloned in plasmid WRG7077. Plasmid construct expressing IL6 was also co vaccinated | — | Pony (n = 25) | Soboll et al., 2003 |
| 10. | Modified vaccinia Ankara vector (MVA) containing HA + NP | Influenza virus-specific lymphoproliferative responses and IFN-γ production against HA and NP | DNA prime-MVA boost vaccination indicated the protective efficacy | HA and NA genes of A/equine/Kentucky/1/81 (Eq/Ky) cloned in an MVA construction plasmid | — | Pony (n = 4) | Breathnach et al., 2004 |