Epidemiology, pathological aspects and genome heterogeneity of feline morbillivirus in Italy

Abstract

A B S T R A C TFeline morbillivirus (FeMV) is an emerging morbillivirus first described in cats less than a decade ago. FeMV has been associated with chronic kidney disease of cats characterized by tubulointerstitial nephritis (TIN), although this aspect is still controversial and not demonstrated with certainty. To investigate FeMV prevalence and genomic characteristics, an epidemiological survey was conducted in a total number of 127 household cats originating from two Italian regions, Abruzzi and Emilia-Romagna. A total number of 69 cats originating from three feline colonies were also enrolled for the study. Correlation with TIN was investigated by employing a total number of 35 carcasses. Prevalence of FeMV RNA was higher in urine samples collected from cats of colonies (P = 31.8%, CI 95% 22.1-43.6) compared to household cats (P = 8.66%, CI 95% 4.9-14.9) and in young and middle-aged cats while prevalence of FeMV Abs was higher in old cats. Sequences obtained straight from infected biological samples, either partial or complete, cluster into two clades within FeMV genotype 1, distantly related to FeMV genotype 2. Immunohistochemistry analysis of kidney sections of FeMV RNA positive cats revealed immunoreactivity within epithelial cells of renal tubuli and inflammatory cells. However, statistically significant association between FeMV and renal damages, including TIN, was not demonstrated (p= 0.0695, Fisher exact test). By virus histochemistry performed with FeMV-negative feline tissues and a FeMV isolate, tropism for different cellular types such as inflammatory cells residing in blood vessels of kidney and brain, airway epithelial cells, alveolar macrophages and to a lesser extent, the central nervous system, was demonstrated. Additional studies are warranted in order to establish viral tropism and immune response during the early phases of infection and to disentangle the role of FeMV in co-infection processes.

Identification of Novel Feline Paramyxoviruses in Guignas (Leopardus guigna) from Chile

“…In our study, only kidney samples were examined, so it cannot be excluded that other organs may also be affected by these guigna paramyxoviruses. For the closely related feline morbilliviruses of domestic cats, histopathological data suggest that other organs (spleen, urinary bladder and immune cells) can be infected with FeMV-1 as well [37]. This finding was also supported by in vitro experiments showing that epithelial cells of the lung, alveolar macrophages and brain tissues are permissive for FeMV-2 under laboratory conditions [24,37].…”

Molecular epidemiology and genome analysis of feline morbillivirus in household and shelter cats in Thailand

“…Since the FeMVs were frequently detected in the urine, previous studies have attempted to figure out the relationship between the presence of FeMV and the pathology of the kidneys [1,8,19,25]. However, there were few reports about a correlation between FeMV infection (identification) and urinalysis parameters [15,26].…”

“…Additionally, the diversity of H gene characterization is potentially affected the host range and virulence [3][4][5][6]. Since the first identification of FeMV in domestic cats showing tubulointerstitial nephritis in Hong Kong in 2012 [ [1], the virus has been investigated in both clinically healthy and ill cats in many countries, such as Japan, Turkey, Germany, Italy, USA, Brazil, and Malaysia [7][8][9][10][11][12][13][14][15][16]. The prevalence of FeMV detection ranges from 0.2-40% based on the tested samples, comprised such as blood, urine, rectal swab, fresh tissues, and formalin-fixed paraffin-embedded tissues [7-10, 12, 14-16].…”

“…Because the first emergence of FeMV was associating with renal disease, the initial studies on FeMV identification were conducted in urine samples, while comparison of FeMV detection in urine and other derived samples was also reported [1,9]. Geographically, the prevalence of FeMV-positive samples is seemingly inconsistent, with a higher detection rate in Japan (ranging from 6.1-23.1%) [9,13,17], Italy (ranging from 1.2-31.8%) [8,18], and Malaysia (50.8%) [12], while a lower detection rate was reported in the USA, Germany, Brazil, and Turkey [7,[14][15][16]18].…”

SARS-CoV-2 RNA Persistence in Naso-Pharyngeal Swabs

“…Therefore, understanding the nature of the test used, and interpreting the results and how these may vary over time in samples collected from the same patient, is of paramount importance [16]. In general, a "positive" molecular result may reflect only the detection of viral RNA and does not necessarily the presence of viable virus [16][17][18]. Nevertheless, a patient with a respiratory tract specimen positive to SARS-CoV-2 RNA may represent an infectious source of COVID-19 [19] and, for the principle of precaution, proper preventive measures must be applied.…”