What to do if your cat has fleas

Fleas are dark brown insects, at 2-4 mm in length, they are visible to the naked eye. They can’t fly but can jump a long way and this is the way they move about.

Like many insects, fleas have a multi-stage life cycle.

• An adult flea lives for 1.5-2 months and during that time lays many eggs. These are laid on the animal host, but most fall in the environment (approximately 95% of them are NOT on the cat).

• The eggs take 1-10 days to hatch and for the flea larvae to emerge from them.

• The flea larvae are tiny worm-like things that don’t feed directly on blood, they lack the mouth parts to bite though the skin, so they feed on ‘flea dirt’, the partially digested blood excreted by adult fleas. They can live both on the cat or in the environment, if there’s sufficient food for them. The larval stage has 3 distinct phases that last 5-11 days and, after the third, the larva turns into a pupa to finish its transformation into an adult flea.

• The flea pupae are egg-like structures with a hard shell that protects the insect while it is transforming into an adult. This stage takes somewhere between 5-150 days, but can take longer if the conditions are not favourable. Being so hardy and not needing any food, pupae can last up to 2 years in the environment.

• After the pupa opens, a new adult flea emerges to repeat the same cycle.

Adult fleas do not live exclusively on a host, hopping on and off. Therefore, they can be found outside, in fields and gardens, or in our homes, sheds etc. However, because they need to feed on blood, they stay close to animals like cats, cats, rabbits, etc.

Because of this, cats with outdoor access can easily pick them up whilst out. For indoor cats the risk of getting fleas is smaller but not zero. Other animals, like dogs, can bring them home after they have been out on walks. Fleas can also hitch a ride with us; they can travel on our clothing, in our vehicles, etc.

What are the symptoms of fleas in cats?

The obvious sign of a flea infestation is the presence of fleas.

Sometimes though, if there are not too many of them or your cat is very good at removing them, or when it’s warm enough in the environment, you might not see fleas on the cat. What you will always find is flea faeces, aka ‘flea dirt’, dark grits in the cat’s coat and on their skin.

Brush your cat’s coat onto a white sheet of paper and wipe the dark grits with a bit of wet cotton wool or add a drop of water on them. Other dirt, like soil, will stay the same while flea dirt (which is partially digested blood) will create a brown-red smear or ring around it.

Other signs you may see in a cat with fleas are:

• itchy skin,

• red and irritated skin,

• bald patches,

• thickened or crusty skin,

• lip sores,

• darkened spots.

In animals that are not allergic to fleas though, these symptoms can be very mild.

To help them feed undetected, fleas use their saliva to numb the skin and prevent the blood at the bite site from clotting. But their saliva contains a lot of proteins and they can cause allergic reactions in some cats, which is known as Flea Allergy Dermatitis (FAD). In such cases the symptoms are similar, but much-much more pronounced and the fleas even harder to detect.

Sometimes fleas will also bite the people in the affected household, especially around the ankles. So if you or anyone in your family starts getting red itchy spots or bumps on their legs, that’s an additional reason to check your cat for fleas or flea dirt.

How to get rid of fleas?

Getting rid of fleas is not that complicated, but it requires time and patience as you must regularly treat your cat, all the other pets and the house itself at the same time for several consecutive weeks.

The fleas on the cat

There are a lot of flea-killing products available in UK, all with different characteristics:

• some of them kill fleas through contact with the chemical on the cat’s coat, others do this when the flea ingests the chemical with the cat’s blood;

• some are freely sold over-the-counter and others only prescribed by vets (the former are often ineffective, so we advise the latter);

• some products kill both adult fleas and larvae, while others work only on adult fleas (eggs and pupae are too impenetrable for anti-flea products).

Speak with your vet who will be able to help you choose the right product for your situation.

It is important to deworm your cat at the same time as the cat flea can carry the larvae of the tapeworm Dipylidium caninum. Cats become infected by ingesting fleas during grooming.

The fleas on other animals

To get rid of the fleas successfully, you must treat all other furry pets that live in your house (or your garden if your cat has contact with them or their bedding) - dogs, cats, rabbits, guinea pigs, etc.

Only use treatments developed specifically for that species. For example, you must never use a dog product on a cat or rabbit, as this causes severe, sometimes even fatal, toxicity.

The fleas in the house

Only 5% of the total flea number is made up of adult fleas on your pets, the other 95% are in the home environment as eggs, larvae and pupae. This means that to clear the flea infestation, you need to treat the house too.

Wash at 60°C everything that your cat uses (bedding, blankets, fluffy toys, etc) and can withstand this temperature.

Flea eggs and pupae are often found in cracks, crevices, and soft furnishings. As mentioned before, anti-flea products don’t affect these life stages that easily. They are the ones that make getting rid of fleas a lengthier process.

To bypass this resistance, start your ‘house treatment’ with vacuuming thoroughly. This has two advantages:

• it physically removes the eggs and pupae from the environment (dispose of the vacuum bag or its content immediately after),

• the vibrations from the vacuum attract the larvae from within their hiding places, but also stimulate the eggs and the pupae to hatch, making them vulnerable to an anti-flea product.

Only after a good vacuuming, use an anti-flea product for the house to kill the larvae and adult fleas hiding in the carpets, floors, furniture.

There are several options available on the market, for example:

• RIP Fleas Extra

• FLEAtec Household Flea Spray

• Household Flea Powder

• Indorex Defence Household Flea Spray

• Frontline Homegard

Carefully read and follow the instructions for use on their package. Keep in mind a few general precautions when using these products:

• Clear the area you are planning to treat of people and pets. Where possible, remove (or at least cover tightly) aquariums, vivariums and water storage tanks.

• Once you have applied the spray or powder, leave the room and allow the product to work for the recommended time (often at least 30 min).

• Ventilate the room thoroughly by opening windows and doors for at least 1 hour before allowing pets or children back into the room.

Additional advice

Don’t panic if, despite your efforts, you still see the occasional flea. If you use a good quality product on your pets, these random fleas come from the pool of eggs and pupae left in the environment. They hatch out in waves, so you need to consistently repeat the treatments of the pets and the house until you don’t see any at all.

If you keep seeing large numbers of fleas despite your efforts, there could be several reasons for that:

• not using the correct treatment on your cat or in your house,

• not treating all the animals in the household,

• not treating other areas that your cat spends time in/on, for example, a scratching post.

Speak either to your registered vet about it or use the button on this page to book a call with FirstVet and one of our experienced vets will analyse the situation with you and recommend the best solutions.