Animal Fleas

Cat Flea (Ctenocephalides felis)
Dog Flea (Ctenocephalides canis)

There are around a thousand species of flea known throughout the world, but by far the most common one found in dwellings around the Western World is the cat flea - responsible for around 75% of all flea infestations. The other major species to cause concern is the dog flea which is normally found on animals and their bedding, and occasionally on humans.

Cat and dog fleas can live on the blood of any warm blooded mammal -but cannot breed without a blood feed from the principal host.

A flea can leap 10 - 15 cms. The human equivalent would be around a hundred or more meters.

A single female is capable of producing up to a 1,000 eggs in her two year lifespan.


Fleas belong to the order Siphonaptera. Fleas vary in colour from light brown to black, but are more commonly reddish brown. They are laterally compressed - flattened from side to side, like a goldfish, and each segment has one or more rows of backward pointing bristles enabling the flea to pass easily through the hair and feathers of the host. Adult fleas live as parasites on warm blooded animals and although they prefer to feed from their natural hosts they will feed from other sources in their absence. The eggs are small pearly white, oval objects -and around 0.5mm in size. These can be seen with the naked eye. The larvae which hatch from the eggs are tiny, white, legless grubs. They are about 1.5 mm long when they emerge and grow to about 5mm prior to pupating. Flea faeces is normally dark brown or black.

Life cycle

The female flea does not lay her eggs until she has fed on blood. Following her feed she will deposit around 4 to 8 eggs in the fur of the host animal, or in the animals bedding . A cat's bedding may support a flea population of 8,000 pre-adult fleas and several thousand adult fleas. The eggs fall away from the animals fur and in a few days hatch into tiny worm like larvae. In homes they develop in crevices, cracks in floorboards, carpets, rugs and on upholstered items. They feed on organic material such as adult flea faeces, and bits of dead skin and hair. The larvae become grey in colour as they grow. After 2 -3 weeks they begin to spin silken cocoons in which they pupate. After about a week, if conditions are right. the adult fleas emerge from their cocoons. The adults can remain dormant in their cocoons for many months if conditions are unfavourable Emergence from the cocoons is normally brought about by certain activity like vibration, temperature change or the presence of carbon dioxide. The whole cycle from egg to adult takes about a month in summer and much longer in cooler conditions.

  • The adult lays 4 to 8 eggs after each blood feed.
  • The eggs hatch after about a week.
  • The larvae feeds on organic waste-undigested blood and excreta from the adults.
  • The larvae grows from 1-5mm in three stages.
  • After 2-3 weeks the larvae spin a cocoon in which they pupate.
  • After about a week they emerge from the cocoon
  • When conditions are right the adult flea will emerge from its puparium in search of a blood feed.

Reason for control

Fleas may go unnoticed for many months before they present themselves as a real nuisance to humans. The real threat comes when humans realise they are being bitten. Family pets also suffer from an abundance of fleas in the home. Bites to humans can cause intense reddened irritation which may last for several days. Continual scratching can cause infection. A few bites are not normally thought to cause any serious reaction, although where bites occur on a regular basis this may lead to hypersensitivity with some people. A typical flea bite has a small central red spot, surrounded by a red halo and a little swelling. Bleeding usually occurs. Flea infestations may last for weeks or months after pets are removed It is thought that up to 50% of all skin diseases suffered by dogs and cats are caused by allergic reactions to flea bites. Fleas are capable of spreading serious disease. The most serious of these being the Bubonic plague carried by the rodent flea from infected rats. The flea is also responsible for carrying murine typhus. Whilst fleas are capable of transmitting serious diseases- in present times they are viewed more of a nuisance and irritation than a risk to health. Fleas present in the home can be a real embarrassment and cause much social stigma.

Control measures

Flea control is best carried out at all three levels of their development, when not present on the host. In order for any control to be effective it is necessary to halt the flea life cycle rather than just treating the flea Correct control measures can only be determined by the severity of the infestation.

Before applying any treatment, carpets, floors and furniture needs to be thoroughly cleaned and vacuumed. Particular attention should be given to pets bedding and areas where pets reside. Domestic pets should be treated regularly with an approved veterinary product. Infested animal bedding should be destroyed, or thoroughly cleaned. When a conventional residual insecticide is used, all rooms should be treated, and any manufactures instructions closely adhered to.

Animal Flea Control Sheffield
Dog Flea

Created by DS Creative