A novel paramyxovirus, feline morbillivirus (FeMV), has recently been detected in a stray cat in Italy (Piuma/2015). According to previous studies conducted in other countries, FeMV has been suspected to be associated with feline chronic kidney diseases (CKD). We aimed at: i) investigating FeMV occurrence in the province of Teramo, central Italy; ii) associating FeMV with CKD lesions; iii) analyzing the genome of circulating FeMVs.

Urine samples collected from cats presented to the Veterinary Teaching Hospital (VTH, UniTE) or to local veterinary practitioners were screened (group A, n 60). In addition, urine from cats (group C, n 72) belonging to 4 colonies were also tested, as well as internal organs of carcasses (group B, n 35). Formalin-fixed and paraffin-embedded sections of kidney of cats were either stained with H&E or incubated with Ab against FeMV-N protein. qPCR-positive RNAs were employed for SISPA/NGS. Finally, a portion of the polymerase (L) gene was amplified by RT-PCR from all positive samples. Carcasses were divided into subgroups, including B1 (+virus +lesions), B2 (+virus -lesions) and B3 (-virus +lesions).

In group A, 7/60 urine samples were positive by qPCR, whereas in group C, 20/72 samples were positive. Eight/35 carcasses resulted positive by qPCR, with kidneys and urinary bladders being constantly positive. Viral RNA was also detected in the brain and spleen of one cat. A bilateral, subacute-to-chronic, lymphoplasmacytic interstitial nephritis was observed in all the qPCR-positive cats, which also showed scattered immunolabeling for viral antigen within their renal parenchyma, mostly involving the cortical kidney tubules and the surrounding inflammatory cells. Sequences of the L gene also have been obtained from all positive samples. Genetic diversity has been observed between different groups. In C1, two putative different viral variants (97.8% of nt id) have been observed, with one of these variants being present in C2. The highest nt difference was shown by most of the obtained sequences from all groups with Piuma/2015 (88.4–88.9% of nt id).

While the occurrence of FeMV in group A mirrors that seen in cats from other countries, FeMV occurrence in group C is higher. As in previous studies, genome diversity also has been demonstrated in FeMVs circulating in our province. We believe that the scattered viral antigen immunolabeling detected in renal tubular epithelia, as well as in the surrounding inflammatory cells, gets along very well with an intermittent viral excretion through urine. Statistical analyses are currently underway.

Disclosures

No disclosures to report