2017 Funded Projects and Outcomes
In 2015 we reported that two commercially available FIV point-of-care test kits (WitnessTM and Anigen RapidTM) were able to differentiate FIV-vaccinated and FIV-infected cats, using a cohort of cats tested at a single time point and a variable amount of time since their last annual booster FIV vaccination (0 to 462 days).
In 2016–17, with funding from the FHRF (awarded in 2015), we serially tested a small group of kittens and cats every two weeks for six months following primary (i.e. initial) FIV vaccination using these two test kits, as well as two additional kits (SNAP ComboTM and VetScanTM). During the six months following primary FIV vaccination we encountered some false-positive results using Witness and Anigen Rapid, but by six months after vaccination false-positive results had ceased to occur with these two kits. Conversely, false-positive results continued to occur with SNAP ComboTM and VetScanTM for the duration of the study.
These findings were important for clinicians as they highlighted a scenario (i.e following recent primary FIV vaccination) when interpreting a positive FIV result using WitnessTM or Anigen RapidTM point-of-care kits needs to be done with caution. In addition, our study demonstrated that that WitnessTM and Anigen RapidTM kits can be used to accurately diagnose FIV infection prior to FIV annual booster vaccination (i.e. 12 months since previous FIV vaccination).
Results from this study were originally published in The Journal of Feline Medicine and Surgery (Westman, M.E., R. Malik, E. Hall, M. Harris, M.J. Hosie, P.A. Sheehy, and J.M. Norris, Duration of antibody response following vaccination against feline immunodeficiency virus. J. Feline Med. Surg., 2017. 19(10): p. 1055–1064).
Results from this study have also been cited in important world guidelines such as The 2020 American Association of Feline Practitioners Retrovirus Testing and Management Guidelines, and also locally in the Australian Veterinary Journal as part of a review that we wrote for Australian clinicians (Westman, M.E., R. Malik, and J.M. Norris, Diagnosing feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV) infection: An update for clinicians. Aust. Vet. J., 2019. 97(3): p. 47–55).
Following on from this study, in 2018–19, with additional funding from the FHRF (awarded in 2017), we serially tested a small group of cats every two weeks for six weeks following their annual FIV booster vaccination using the same two test kits (WitnessTM and Anigen RapidTM). Results from this more recent study demonstrated that false-positives did not occur in cats recently administered an annual FIV booster vaccination. This finding suggests that the antibody response that occurs following annual booster FIV vaccination is significantly reduced compared to the antibody response that occurred following primary FIV vaccination, an immunological phenomenon that has also been reported with a hepatitis B vaccine in people.
This finding has immediate clinical application for Australian veterinarians as it means that FIV testing can be safely performed in cats that have recently received an annual booster FIV vaccination using one of the two point-of-care FIV kits tested. We aim to publish these results in The Journal of Feline Medicine and Surgery in 2020.
2017 Round 2
Investigating feline morbillivirus epidemiology in domestic cats in Perth, Western Australia
Dr C Sharp, Dr T Hyndman, Dr T O’Dea
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Helen Radoslovich: 0408 812 319