A commercially available hyperimmune serum, that contains antibodies to the pathogens that commonly cause feline upper respiratory tract disease (FURTD), can shorten recovery time from 7 to 3 days.

In a recent study published in The Veterinary Journal, researchers compared two groups of cats suffering from FURTD caused by feline calicivirus (FCV) or feline herpesvirus (FHV-1). One group received the hyperimmune serum, the other received a placebo, and both received treatment for their symptoms.

From the study abstract:

Clinical signs and health status in both groups improved significantly over time (P < 0.001). Cats receiving hyperimmune serum significantly improved in terms of ‘FURTD score’ (P = 0.046) and general health status (P = 0.032) by day 3, while cats in the placebo group only improved significantly by day 7. There was no significant difference in the number of cats shedding FCV between the two groups. Thus, administration of hyperimmune serum led to a more rapid improvement of clinical signs in cats with acute viral FURTD, but by day 7, clinical signs had improved equally in both groups.

Yvonne Friedl, Bianka Schulz, Anne Knebl, Chris Helps, Uwe Truyen, Katrin Hartmann, Efficacy of passively-transferred antibodies in cats with acute viral upper respiratory tract infection, The Veterinary Journal, Available online 6 May 2014, ISSN 1090-0233, http://dx.doi.org/10.1016/j.tvjl.2014.05.002.