cat viruses
Feline viruses
FeLV | · Feline leukaemia virus – RNA retrovirus · Transmission: o Mother ® kitten (transplacental, through milk, through saliva when grooming) o Horizontal transmission – through saliva (grooming, fighting, sharing food bowls) · Pathogenesis: o Transmitted when contact with virus-containing saliva, virus replicates in LNs ® travels around the body § Lymphoid tissue and bone marrow ® affects peripheral blood and leukocytes § Epithelial cells ® affects secretory cells ® further spread · When infected – either: o Cat fights off infection, no clinical signs, has ab but not ag o Progressive infection: virus in bone marrow, viral ag in blood, PCR positive o Regressive infection: virus in bone marrow, no viral ag in blood, PCR positive · Presentation: lymphopenia, neutropenia, impaired neutrophil function, loss of CD4+/CD8+, anaemia (regen or non-regen), neoplasia · Transient infection, shortens life-span |
FIV | · Feline immunodeficiency virus – RNA retrovirus · Transmission: deep wounds inoculated with saliva (due to aggression) · Pathogenesis: o Infects T-helper cells, dendritic cells and macrophages – crucial for cell-mediated and humoral immunity o Detect in circulation – see slow increase in viral particles · When infected: o Primary infection – lymphocytes decrease as fighting infection o Lymphocyte count increases after primary infection, then slowly decreases with age ® allows gradual increase in virus o Sudden rapid increase in virus ® death · Presentation: stomatitis (due to overstimulation of mucosa) · Infected for life, but may have normal lifespan |
FIP | · Feline infectious peritonitis – enveloped RNA virus · Pathogenesis: o Secondary to feline enteric coronavirus – most cats have minimal clinical signs and fight off infection o But some cats develop FIP due to virus mutation · Presentation: o Effusive = wet form § Virus causes inflammatory vasculitis ® increased permeability ® effusions) o Non-effusive = dry form § Ocular and neurological presentation |