Prospective investigation of feline bocavirus persistence and shedding in naturally infected cats from varied household settings

ObjectivesFeline bocavirus (FBoV) is a single-stranded DNA virus of the genus <i>Bocaparvovirus</i>, family <i>Parvoviridae</i>. First identified in 2012, it comprises three species - FBoV-1, FBoV-2 and FBoV-3 - and is globally distributed. Although associated with gastrointestinal disease in cats, its pathogenesis and shedding patterns remain unclear. This study investigated the shedding dynamics of FBoV in naturally infected cats with gastrointestinal signs.MethodsA longitudinal sampling approach was employed in three separate multi-cat households, involving seven symptomatic cats across multiple time points. Initial FBoV screening was performed using conventional PCR and three singleplex TaqMan-based quantitative PCR (qPCR) assays were developed to detect and quantify FBoV-1, FBoV-2 and FBoV-3. The established singleplex qPCR assays were used for subsequent monitoring. Coinfection with other enteric viruses, particularly feline coronavirus (FCoV), was also evaluated.ResultsFBoV-1 and FBoV-2 were detected in multiple cats from house A, with coinfection observed in 5/9 (55.6%) cats and FBoV-1 alone in 1/9 cats. In contrast, only FBoV-1 was identified in cats from houses B and C. FCoV was frequently codetected in all households. qPCR revealed significant variation in viral load over time and across sample types. Positive viral detection persisted for 10-14 days after the resolution of clinical signs in most cases. Notably, one hospital-resident cat continued to present FBoV-1 for up to 65 days.Conclusions and relevanceThis is the first study to characterise FBoV load, and possibly shedding dynamics, in naturally infected cats using route-specific sampling and species-specific quantification. Findings demonstrate that FBoV can be present well beyond the clinical phase of illness, highlighting the possible risk of prolonged transmission or shedding in multi-cat environments. These insights are important for understanding FBoV pathogenesis and developing effective feline disease control strategies.