Flea Information – Fact Sheet

29 / Aug / 2018
Flea Information – Fact Sheet

Fleas (Ctenocephalides felis felis- the common flea), these ectoparasites can make our lives and our pets miserable with the vicious cycle of scratching and biting of the skin. The best way to combat fleas is to understand their lifecycle. It is important to understand that the fleas on a pet represent only 5% of the total flea cycle, the remaining 95% of the flea’s lifecycle (eggs, larvae and pupae) are located in the environment where your pet lives and are waiting to hatch and jump onto your pet.

There are several stages to the flea life cycle- egg, larva, pupa (cocoon) and adult. The length of time it takes to complete this cycle varies depending upon the environmental conditions such as temperature, humidity and availability of a host. Hence the complete life cycle can be complete anywhere from 12 days up 325 days.

Fleas lay eggs whilst on your pet. One female can lay up to 50 eggs per day. These eggs then fall off the pet into the environment as your pet moves around the house, garden and particularly where your pet sleeps. These eggs then proceed to develop where they land. The egg then takes up to 10 days depending on humidity and temperature to hatch into larvae.

Larvae are wormlike creatures that are phototactic (move away from light) and hide in all the nooks and crannies like among carpet fibres, cracks in the floor and outside in the environment. The larval stage lasts 5 to 11 days depending on food availability, temperature and humidity. They feed on organic matter and grow, moulting twice and then form a cocoon and pupate, waiting for the right time to hatch into an adult.

Pupae are very resilient and are protected in their cocoon. This means flea control products and pesticides will not kill this stage of the life cycle. Pupae generally mature into an adult flea in 5 to 9 days but can stay in their cocoon for up to 1 year, waiting until environmental conditions and host availability is just right.

The new adult flea will emerge from their cocoon which is located in the environment when they detect heat, vibrations and exhaled carbon dioxide, all of which indicate that a host is nearby. Your family and pets provide these stimuli and cause emerging adult fleas to jump on to you or your pet in less than 1 second. The newly emerged adult flea begins to feed almost immediately (0 to 60 seconds) after jumping onto an available host. About 2 to 3 days after a female has had her first blood meal, she will start to lay eggs, which start the life cycle over again.

Fleas do not just affect dogs and cats but are found on a variety of wild and domestic animals. Some examples of other types of animals that are affected by fleas are rodent species, ferrets, lizards, rabbits, horse, birds and poultry. These non-treated hosts which can enter your pet’s domain may be the cause of environmental contamination.

The flea is a permanent ectoparasite and does not transfer from one animal to another, nor does it leave the animal to lay its eggs. Flea free animals do not pick up fleas through contact with infested animals, rather they pick up fleas through contact with infested environments such as your pets bed, the backyard, your house, a park, the garden, under the house and even other people’s houses.

It is also important to understand that in environments that are only lightly infested, humans are not normally targeted and only minimal fleas are noticed if at all on a pet. If however a house or areas (e.g. under a house, backyard) is left vacant for a period of time (e.g. you go on holiday), there may be a spontaneous emergence of the fleas from their pupa stage when the home or area is re-entered. This may result in a high infestation. In this situation humans may also be targeted as well as your pet with number of fleas being noticeable.

Knowing the flea life cycle indicates the importance to treat the host animal and the indoor as well as the outdoor environment in order to control fleas. To achieve effective flea control it is recommended to:

• Treat all pets (e.g. dogs and cats) in your household, ensuring flea treatments are applied with the correct dose at recommended control intervals throughout the entire year with a recommended flea treatment. Missed flea treatments can allow large numbers of fleas to build up in the environment, so treating all household pets at the recommended control interval will prevent the development of flea infestations on your pet and in the environment. Please consult your veterinarian for effective flea control advice.

• Regularly vacuuming or sweeping away debris including pet hair from the environment especially from cracks in floorboards and under furniture will assist in the removal of eggs and stimulate new fleas to emerge (which the flea control treatment then will help kill).

• Steam cleaning carpet and mopping helps also assist with combating flea infestation.

• Regularly washing your pet’s blankets and bedding in hot water (about 60°C for 10 minutes), helps stop the flea lifecycle.

• Avoid untreated animals entering your home environment.

• Reduce outside sources of flea contamination; this can be achieved by blocking pet access to under the house, keeping moist shady areas free from organic material by mowing, raking and discarding debris particularly in areas with no direct sun exposure.

• Pay particular attention to outside areas especially your pets favourite sleeping area (e.g. under a patio or veranda) or inside your pet’s kennel.

• You may need to use a registered pesticide to assist with environment flea control. Registered products for environmental treatment (e.g. aerosol fogger, hand held sprayer) have a disadvantage which may include poor penetration and dispersal of the product.