Feline Chlamydiosis

Feline Chlamydiosis

Feline Chlamydiosis

Cats are susceptible to infections of the respiratory system, and it can be very difficult to unravel the cause, especially because there can often be more than one type of infection present at the same time. It is now becoming clear that feline chlamydiosis is perhaps more of a problem than was thought in the past, with many cats now known to carry the chlamydial organism responsible, although it does not always result in illness.

Conjunctivitis is frequently the most obvious sign of feline chlamydiosis. Keep the fur around the eyes clean by wiping it, and check with your vet whether eye drops are required.

Is is just the eyes that are affected in Feline Chlamydiosis?

Cats will occasionally sneeze as well, which is how this infection can be transmitted in a cattery. In weakened individuals, a more generalised respiratory illness may be linked with chlamydiosis.

What is the treatment for this condition?

Your vet is likely to prescribe a combination of both ophthalmic medication, in the form of drops or an ointment which need to be administered directly to the eyes, and a long-term course of antibiotic tablets or possibly antibiotic injections.

Can I get chlamydiosis from my cat?

The risk is very slight. But take precautions, by always washing your hands thoroughly after treating your cat, and don’t touch your own eyes during this process.

Chlamydia is an organism that causes disorders in a cat’s respiratory system, resulting in conjunctivitis (inflammation of the conjunctivae, the mucous membranes covering the eyes). Although it is not a true bacteria, chlamydia can be eliminated by treatment with antibiotics of the tetracycline group.


Even so, it is important not to cease treatment too early, because although the symptoms of runny, sticky eyes will have disappeared, the chlamydial organisms themselves may still be present. This means that there is a chance of obvious signs of infection returning again in the future, particularly if the cat becomes stressed. Cats carrying the illness in this way also represent a danger to others, with the infection often spreading quite easily within the confines of a cattery.


There is now a vaccine however, which can be helpful, particularly if given to pregnant queens late in pregnancy. A killed vaccine must be used at this stage, and will help to boost the mother’s immunity to feline chlamydiosis, which in turn will be passed on to her kittens. Young cats are particularly vulnerable to this infection, and so it is a good idea to arrange for them to be vaccinated by your vet. This is usually done when kittens are 12 weeks of age. An annual booster is then required, with the chlamydial vaccine often being combined into one shot which protects against all the major serious feline respiratory infections.

Kittens are particularly susceptible to chlamydial infection because their respiratory systems are weaker than those of most adult cats, and it may spread quickly through a litter. Chlamydia is thought to be spread mainly in the mucus emitted by a cat when it sneezes. Treatment is with antibiotics (tablets or injections) , which must be continued until the infection has completely cleared. Eye drops may also be prescribed to relieve the symptoms.

  • Chlamydia can affect a wide range of animals, with specific strains being identified in creatures as diverse as frogs, sheep and parrots.
  • Human strains can also affect the eyes, but you can’t be sure that you have acquired an infection of this type from your cat without medical tests. It could just be coincidence.
  • It is vital to treat the eyes at least four times daily with antibiotic drops or an ointment, otherwise the tear fluid will wash the medication out of the eyes before it can be effective.