CPD ACCREDITED ARTICLE
management and veterinary care , an FeLV-infected indoor-only cat may live much longer with a good quality of life . Focal infection may occasionally occur ; it is characterized by persistent atypical local viral replication ( such as in mammary glands , the bladder or the eyes ) 4 , 10 .
FeLV-associated diseases include lymphoma , leukaemia , anaemia and infectious diseases that are potentiated by the virus ’ immunosuppressive effects . Outcomes of FeLV infection depend on an individual cat ’ s immune status , genetic makeup and age , the presence of any other infectious diseases , and the pathogenicity and infectious dose of the FeLV virus .
Determine FeLV status of all cats in a household
If a cat tests positive on a screening test for FeLV , it should be confirmed as “ true positive ” with a confirmatory test ; both tests are typically performed on peripheral blood . Screening tests are usually ELISAbased tests designed to detect p27 FeLV antigen , and most cats will test positive within 30 days of exposure 11 . Recommended confirmatory tests are either indirect fluorescent antibody ( IFA ) tests that detect p27 FeLV antigen in infected leukocytes or platelets , or polymerase chain reaction ( PCR ) -based tests that detect FeLV provirus . IFA tests don ’ t usually yield positive results until secondary viraemia has occurred after infection of bone marrow ( about 45 to 60 days after initial infection ).
The stage ( abortive , regressive or progressive infection ) should be determined for all FeLV-infected cats . Abortive infected cats will test FeLV-negative and IFAor PCR-negative , but they will seroconvert and test FeLV antibody-positive ; however , antibody testing isn ’ t usually performed in a clinical setting . Regressively infected cats usually test FeLV antigen-negative no later than 16 weeks after infection , while progressively infected cats remain FeLV antigen-positive 12 . Both regressively and progressively infected cats can test PCR FeLV provirus-positive as soon as two weeks after infection and they will remain positive thereafter 13 , 14 .
Here are some additional principles for FeLV testing
• Any new cats or kittens should be screened for FeLV infection before being introduced into a household .
• Household cats that go outdoors or share a house with cats that go outdoors should be FeLVtested at least yearly . Also , any cat that becomes clinically ill should be tested for FeLV immediately if it shares a household with an FeLV-infected cat .
• Household cats that may have been exposed to other cats with unknown FeLV infection status should be immediately tested for FeLV and retested six weeks after exposure . In some cats it can take up to four months to figure out the stage of FeLV infection . In a multicat household , it can be difficult for the owner to confine FeLV-exposed cats , assess risk to other cats , and decide how to manage the situation . Close partnership with the veterinary team is essential in these situations .
• FeLV tests detect infection , not clinical disease . A decision for euthanasia should never be based solely on whether a cat is “ confirmed ” FeLV-infected . While FeLV infection can be lifethreatening , proper management and prompt veterinary care can help regressively and even progressively infected cats have long , healthy lives with good quality .
• Which cats should be vaccinated for FeLV ? The decision to vaccinate an individual cat against FeLV is based on risk assessment for infection and lifestyle . Cats that should be vaccinated include :
1 . Kittens , because they ’ re more susceptible to infection and their lifestyle is still in flux . Note that although FeLV infection susceptibility decreases as cats get older , the risk does not necessarily reach zero ; it depends highly on a cat ’ s lifestyle and degree of viral exposure .
2 . Cats with access to the outdoors and cats that have contact with cats with access to outdoors . 3 . Cats that live with FeLV-infected cats . 4 . Cats that may encounter other cats with unknown FeLV status .
Managing healthy FeLV-positive cats
If a cat is FeLV-positive but displaying no clinical signs , it should receive a physical examination at least twice a year and at each veterinary visit , with attention paid to unintentional weight loss , enlarged lymph nodes , clinical signs of upper respiratory infection ( e . g . ocular or nasal discharge ) and oral health . All cats should have the anterior and posterior segments of the eye thoroughly examined . Complete blood count , biochemical profile , urinalysis , urine culture and fecal examination are indicated at least once a year . Some fragile FeLV cats may need bloodwork , urinalysis and faecal examination more frequently . Infected queens and toms should not be bred , and they should be spayed or neutered , respectively , to reduce behaviors that increase risk of disease exposure or transmission , such as escaping , fighting and roaming . Routine gastrointestinal and external parasite controls should be provided .
Some FeLV-infected cats have been shown not to mount an adequate protective response to rabies vaccination 15 ; therefore , it ’ s prudent to advise owners that FeLV-infected cats should not have outdoor access , especially in rabies-endemic areas .
Regardless , FeLV-infected cats should still be vaccinated with core vaccines ( rabies , feline herpesvirus , vet360
Issue 02 | MAY 2018 | 6