Rabies Infection in Cats – World Rabies Day

How seriously do you take rabies in cats?

If you live in a rabies-free country, this isn’t something you think much about, unless planning to travel abroad. However if you live in a country with endemic rabies, the disease must be taken extremely seriously, given that there’s no cure, it’s fatal, and can be passed to people.

However, regardless of where you live, it’s good to know how rabies could impact on your life; such as knowing what signs to be vigilant for and under what circumstances vaccination is necessary.

Rabies in Cats: Did You Know…?

Rabies is a fascinating disease.

It presents in two forms: The “furious or rage” form from which the French so evocatively name rabies “La Rage”, and the “dumb” or silent form. These pretty much do what it says on the label with the slavering, aggressive animal that bites indiscriminately being the typical poster child of the ‘rage’ form.

However, any major about turn in an animal’s behaviour can be an indication of rabies, from the shy pet that becomes uncharacteristically affectionate, to the soft-as-butter pet that turns unaccountably aggressive.

Did you know that different species have a different propensity to the “rage” form, for which cats head the table.

• Cats: 95% of those infected with rabies develop the “rage” form
• Humans: 80% develop “La rage”
• Dogs: 25% develop the rage form

Some other salient statistics include:

• Each year more than 50,000 people are infected with rabies worldwide. Of these, very few survive.
• Dogs are a bigger source of infection to people than cats.
• Cats require a high dose of rabies virus in order to become actively infected.
• Vaccination reduces the risk of rabies developing, but does not eliminate it altogether.
• Hydrophobia (fear of water) only develops in people infected with rabies.

All About Rabies Infection in Cats

Countries such as the UK and Australia that are rabies free are keen to keep it that way. This is because rabies affects all mammalian species, which means if it gets into the native wildlife then infection could run out of control. Indeed, each country has a different “reservoir” animal which poses a threat to people and domestic animals.

These reservoir hosts are:

• In Europe, the red fox
• In the US, the racoon and skunk
• In South Africa, the mongoose

To become infected the rabies virus must directly access the victim’s blood stream, making bites the number one source of infection, although a clinically infected pet licking an owner’s open wound is another possible method of transmission.

However, an infected animal isn’t infectious to others until relatively late in the disease. This is because of the fantastical way rabies infection spreads through the body. Indeed, this is also why the incubation period between infection and symptoms ranges from five days to 12 months (with an average of 8 – 12 weeks.)

This is because the rabies virus goes on a journey from the bite wound to the brain, with the length of the incubation period reflecting how long it takes the virus to reach the head. Take a look at the route the virus travels within a newly infected cat:

• After a bite from an infected animal, the virus multiplies in the muscles around the bite wound.
• Virus travels to the nerve endings and uses them as a highway to leave the site.
• As little as 10 hours post infection, the virus is no longer present at the bite wound.
• The virus migrates along the nerves, travelling at a rate of 3mm per hour.
• Via nerves the virus enters the spinal cord.
• Virus now spreads to salivary glands (the cat is now infectious to others) and brain, so clinical signs develop.

The signs of rabies depend on the form, but include:

• Uncharacteristic, uncontrollable behaviour changes
• Decreased appetite
• Mental confusion
• Loss of inhibitions, leading to the urge to bite indiscriminately
• Altered voice
• Heavy salivation and drooling (due to an inability to swallow)
• Loss of appetite
• Muscular weakness

Diagnosis and Treatment

Fortunately, cats require a higher initial dose of rabies virus to become infected. Unfortunately, once infected there is little that can be done. To complicate matters no lab test can diagnose active rabies infection, other than examining the brain under a powerful microscope. This means diagnosis is challenging and those animals showing signs consistent with rabies are often destroyed, rather than put people at risk.

Rabies and Vaccination

In the United States, it is a legal requirement in many states to get your pet cat vaccinated against rabies. The duration of each shot’s protection varies from one to three years, depending on the vaccine manufacturer’s product. Speak to your vet about a suitable protocol to protect your pet.

In cats older than 12 weeks, a single shot is all that’s required to provide initial protection. This must then be actively topped up at yearly or three-yearly intervals as specified by your vet.

In rabies free countries there is no legal requirement to vaccinate; indeed, in some countries special permission is needed from the government in order to vaccinate a domestic pet against rabies.

Travelling Abroad with Your Cat

If you are travelling abroad with your cat, do your homework carefully beforehand. Each country you enter has their own entrance requirements which you pet needs to meet. These can be onerous and include proof of the pet’s identity, plus blood work to prove successful vaccination.

Allow yourself plenty of time, because if the cat does need a rabies vaccine, time must elapse before the blood test is taken.

The best source of information is the embassy of the country you intend to travel to. They should have all the details you require and can issue the supporting official travel documents necessary to allow the pet to enter their country.

World Rabies Day is held annually on September 28. It aims to raise awareness about the public health impact of human and animal rabies.