CAT 'FLU
Cat 'flu remains a depressingly common experience, despite
the important contribution made by vaccines. The disease can
vary in severity, but kittens are particularly at risk and
entire litters have been known to die soon after contracting
it.
Who is at risk?
Cat 'flu is most commonly seen in situations where cats are
kept in large groups such as breeding catteries, rescue centres
and feral cat colonies, although it can also be seen in pet cat
households. Cats most at risk include unvaccinated cats, kittens,
the elderly and cats which are immunosuppressed for any reason.
Causes and symptoms
Despite the name, the causes of cat ‘flu bears no relation
in those of human influenza. Whereas influenza is caused by a
single virus, cat ‘flu is a syndrome: the signs of this
disease may be caused by one or more of several different infectious
agents (pathogens). Symptoms include sneezing, nasal discharge,
conjunctivitis (inflammation of the lining of the eyes), discharge
from the eyes, loss of appetite, fever and depression. Occasionally,
mouth and eye ulcers and excessive drooling of saliva may be
seen. The very young, very old and immune suppressed cats are
more likely to develop severe disease and possibly die as a result
of their 'flu.
There are primarily three known primary pathogens, capable of
causing cat ‘flu on their own. These are feline herpesvirus
(FHV), feline calicivirus (FCV) and the bacterium Bordetella
bronchiseptica. Respiratory disease problems within a household
or cattery environment may involve one or more of these infectious
agents.
Feline herpesvirus (FHV)
Although the majority of cats infected make a full recovery,
this often takes several weeks and some cats are left with permanent
effects of infection such as recurrent eye problems and chronic
rhinitis (inflammation of the nose). Cats with chronic rhinitis
are usually well in themselves but have a persistent discharge
from the nose. Secondary bacterial infection of damaged tissue
can cause chronic conjunctivitis, sinusitis and bronchitis (inflammation
of the linings of the eyes, sinuses and air passages). Antibiotic
treatment usually only provides temporary relief of these symptoms.
Herpes carriers may come down with cat ‘flu (clinical
signs and viral shedding) following stressful events, like staying
in a cattery, many months after first catching the disease.
Feline calcivirus (FCV)
Infection usually causes a milder form of cat 'flu with less
dramatic nasal discharges. Characteristic mouth ulcers are sometimes
the only sign of infection. The ulcers may be present on the
tongue, on the roof of the mouth or the nose. Some strains of
FCV cause lameness and fever in young kittens. Affected cats
recover over a few days although they may benefit from pain killers
at this time.
Calicivirus carrier cats shed virus continually with most cats
eventually becoming carriers, but some are persistently-infected – sometimes
this is associated with mouth inflammation (gingivostomatitis).
Bordetella bronchiseptica (Bb)
This infectious bacterium is more commonly known as the most
important cause of canine infectious tracheobronchitis (Kennel
Cough). However, this bacteria also causes respiratory signs
in cats that can be hard to differentiate from cat ‘flu
caused by viral infections. Bordetella can be a particular threat
to young kittens and occasionally whole litters of kittens may
be lost to this infection.
Cats that recover from cat ‘flu are often unable to completely
eliminate the viruses or bacteria from their body and many become “carriers”,
able to transmit the disease to other cats for years.
How is it spread?
The cat ‘flu viruses and bacteria are relatively sturdy
and can survive in the environment for several days. They are
spread through direct contact with an infected cat showing signs
of 'flu or disease, from direct contact with a contaminated environment
(eg: clothing, food bowls and other objects) and from contact
with a cat that is a carrier of cat 'flu (that may or may not
be showing signs of disease).
Prevention and control
The risk of developing cat 'flu can be reduced by regular vaccination
against FHV, FCV and Bordetella bronchiseptica. |