Plus-Hex CLINICAL
ABSTRACT There are limited data on whether neutering a cat affects its risk of contracting feline immunodeficiency virus ( FIV ). A group of cats must be sampled and data collected to examine whether a correlation exists between disease prevalence and neuter status .
This comparative study aimed to determine whether the neuter status of cats affected the rates of FIV positivity among the stray cat population of a north London RSPCA hospital .
Data were collected from the RSPCA ' s ‘ Stray Cat Archives 2019 ’ and stored in Microsoft Excel . The data were analysed using Minitab 15 software . Of 869 stray cats admitted into the hospital , 433 were tested for FIV and feline leukaemia virus ( FeLV ) using the combined MEGACOR FASTest . Of the cats tested , 20 % tested positive for FIV and , of these FIVpositive cats , 89 % were entire males .
The results indicate that entire male cats are substantially more predisposed to being infected with FIV than neutered male cats , entire female cats and neutered female cats .
After initial exposure to the virus , the host will become acutely unwell [ 10 ] with clinical signs such as lethargy , pyrexia and lymphadenopathy [ 11 ] , which normally subside within 12 weeks of the peak virus levels . Following this , the patient will show no clinical signs for a period [ 10 ] , but the virus will continue to replicate . Disease progression varies from patient to patient [ 12 ] , but the end stage leads to an immunocompromised state [ 13 ] . Patients will usually succumb to a secondary condition , for example , neoplasia , opportunistic infection or neurological decline . This is often referred to as feline acquired immunodeficiency syndrome or FAIDS [ 14 ] .
Infection and transmission
It is reported that FIV cannot survive outside an infected host for a long period of time [ 15 ] . The risk of a non-infected cat contracting the virus from an infected cat , through sharing resources or cohabiting , is reported to be low [ 10 ] . FIV can pass from a queen to her kittens during pregnancy or lactation [ 16 ] . However , the most common route of viral transmission has been identified as an invasive exchange of infected blood or saliva [ 10 ] , often in aggressive incidents such as fighting and biting ( Figure 1 ).
Keywords FIV , immunodeficiency , virus , neuter , castrate , stray , cat , feline , charity
Introduction
Feline immunodeficiency virus ( FIV ) is a prevalent infection that affects cat populations worldwide . Belonging to the Retroviridae family ( retroviruses ), in the genus Lentivirus [ 1 ] , FIV causes a disease that is often debilitating in the final stages . FIV was initially identified in 1986 [ 2 ] , when a group of house cats presented with abnormally high rates of opportunistic infections . However , retrospective research suggests the viral infection may have been present in cats since 1966 [ 3 ] . FIV is currently recognised as endemic among the domestic cat population [ 4 ] .
Pathogenesis
FIV is routinely studied to extend knowledge of human immunodeficiency virus ( HIV ) [ 5 ] and further treatment models . The viruses have a comparable structure and there are similarities in the stages of disease progression [ 5 ] .
On infection , retroviruses replicate within a host ' s cell , integrating the viral genome into the infected individual ' s DNA [ 6 ] . This infection remains with the patient for life [ 7 ] . FIV targets white blood cells , specifically CD4 + and CD8 + T cells , resulting in alteration of the CD4 + / CD8 + T-cell ratio [ 8 ] . These cells facilitate the immune response required to combat invasive pathogens such as bacteria and viruses [ 9 ] .
Figure 1 . FIV can be transmitted through the invasive exchange of infected blood or saliva in incidents such as fighting and biting .
Volume 39 ( 3 ) • June 2024
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