A novel video tracking method to evaluate the effect of influenza infection and antiviral treatment on ferret activity.
Ferrets are the preferred animal model to assess influenza virus infection, virulence and transmission as they display similar clinical symptoms and pathogenesis to those of humans. Measures of disease severity in the ferret include weight loss, temperature rise, sneezing, viral shedding and reduced activity. To date, the only available method for activity measurement has been the assignment of an arbitrary score by a 'blind' observer based on pre-defined responsiveness scale. This manual scoring method is subjective and can be prone to bias. In this study, we described a novel video-tracking methodology for determining activity changes in a ferret model of influenza infection. This method eliminates the various limitations of manual scoring, which include the need for a sole 'blind' observer and the requirement to recognise the 'normal' activity of ferrets in order to assign relative activity scores. In ferrets infected with an A(H1N1)pdm09 virus, video-tracking was more sensitive than manual scoring in detecting ferret activity changes. Using this video-tracking method, oseltamivir treatment was found to ameliorate the effect of influenza infection on activity in ferret. Oseltamivir treatment of animals was associated with an improvement in clinical symptoms, including reduced inflammatory responses in the upper respiratory tract, lower body weight loss and a smaller rise in body temperature, despite there being no significant reduction in viral shedding. In summary, this novel video-tracking is an easy-to-use, objective and sensitive methodology for measuring ferret activity.
WHO Collaborating Centre for Reference and Research on Influenza, VIDRL, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, 3000, Australia; School of Applied and Biomedical Sciences, Federation University, Churchill, Victoria, 3842, Australia.
Ding Yuan
DY
Oh
WHO Collaborating Centre for Reference and Research on Influenza, VIDRL, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, 3000, Australia; School of Applied and Biomedical Sciences, Federation University, Churchill, Victoria, 3842, Australia.
Ian G
IG
Barr
WHO Collaborating Centre for Reference and Research on Influenza, VIDRL, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, 3000, Australia; Melbourne School of Population and Global Health, University of Melbourne, Parkville, Victoria, 3010, Australia.
Aeron C
AC
Hurt
D000818:Animals; D000998:Antiviral Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001522:Behavior, Animal / Q000187:drug effects*; D005260:Female; D005289:Ferrets / Q000821:virology*; D053118:Influenza A Virus, H1N1 Subtype / Q000187:drug effects / Q000502:physiology*; D008297:Male; D009976:Orthomyxoviridae Infections / Q000188:drug therapy*; D053139:Oseltamivir / Q000494:pharmacology* / Q000627:therapeutic use; D014741:Video Recording
D000998:Antiviral Agents; D053139:Oseltamivir