Current perspectives on control of equine influenza.

The research paper discusses the control of equine influenza (horse flu) caused by certain variations of the Influenza A virus. Notably highlighting that in spite being vaccinated, horses can still carry the virus and spread the disease under certain circumstances. Developments in vaccination, diagnostic techniques, and global surveillance of the disease are also touched on in this research article.

Disease Control Strategies

• In the fight against equine influenza, the paper reveals that subclinical infections can still happen even in vaccinated horses, particularly if there’s a discrepancy between the strains in the vaccine and those in the field. In such cases, afflicted horses may still shed the virus, inadvertently promoting its spread.
• To counteract this, rapid diagnostic techniques, capable of detecting influenza virus antigens, have been established to aid control schemes. This helps to swiftly identify and isolate carriers, thereby mitigating the spread of infection.

Vaccine Standardization and Efficacy

• The research talks about advancements in the standardization of inactivated virus vaccines. A correlation has been found between vaccine effectiveness, represented by single radial diffusion (a technique to measure varyuing concentrations of antigen in the vaccine) and the vaccine-triggered antibody response, shown by single radial haemolysis (a technique for measuring the antibody in serum).
• Besides these, the paper states that augmented adjuvants (substances which improve the body’s immune response to a vaccine) and antigen presentation systems aid in prolonging the immunity duration provided by inactivated virus vaccines.
• However, it’s important to note that a high level of antibodies is crucial in safeguarding against a field infection.

Live Attenuated Vaccines and Immunity

• This research paper also throws light on more contemporary types of vaccines available now, namely live attenuated or vectored equine influenza vaccines. These vaccines are believed to better simulate the immunity generated by an actual influenza infection, as opposed to inactivated virus vaccines.
• This paper also points out that in addition to circulating antibodies, an influenza virus infection can stimulate mucosal and cellular immunities. Unlike inactivated virus vaccines’ immunity, the immunity induced via infection doesn’t depend on the presence of “circulating antibody to HA” or the Hemagglutinin antigen on the influenza virus.

Mathematical Models and Global Surveillance

• An interesting aspect discussed by the authors is the application of mathematical modelling, based on experimental and field data, to study issues related to vaccine efficacy at a community level.
• Further, a worldwide surveillance system is being developed to monitor equine influenza and a vaccine strain selection process has been implemented to improve the effectiveness of the vaccines.