Fleas are categorised in the order Siphonaptera. There are more than 3,000 species fleaof fleas in the world. However, only less than 20 species are important to the medical and veterinary fields. Fleas are considered pests mainly because they are blood-sucking insects. They are considered external parasites. An adult flea is known to be a carrier for a number of serious diseases such as bubonic plague, tungiasis and typhus. The deadly bubonic plague wiped out half of the European population during the 14th century.


Fleas are small, wingless insects whose average adults measure 1-4mm. They undergo complete metamorphosis lifecycle: egg, larva, pupa and adult. An adult flea is usually dark colour such as reddish-brown. Its body is laterally compressed (flattened side-by-side), permitting easy movement through the hairs or feathers on the host’s body.

Eggs are normally whitish in colour and lay among the hairs of the host or in nests. Normally, female fleas lay about 20 eggs per batch. A single female is able to lay several hundreds of eggs over a period of 2 to 4 months. The primary habitat of eggs is the place where the host rests and sleeps. The eggs take two days to two weeks to hatch.

The larvae are legless with chewing mouth-parts. They are covered with bristles. They are blind and avoid the sun or any form of light. They prefer sandy places such as the host’s potty, cracks and crevices, and beddings. They feed on organic debris and the faeces of adult fleas.

After going through 3 larval stages which take 1 to 2 week with sufficient food, the larvae will turn to pupae. The pupa stage normally takes 1 to 2 weeks time before a pupa turns to an adult. However, under certain critical conditions, pupae may survive up to a year. The emergence of adult fleas from pupae is enhanced by the vibration caused by people walking from external surroundings, heat and carbon dioxide. This is why people who enter an infested vacated house will complain about the presence of fleas.

Fleas need a host to have a blood meal. Adult fleas require a blood meal to become reproductive. In urban pest management, the common hosts of fleas are dogs, cats, rats and birds. They are known as ideal disease transmitters because of their long lifespan. Unfed adult fleas may live up to a year while fed fleas may live up to 5 years.

Fleas prefer dark and usually avoid light. They normally stay on the body of the host because they need to suck blood several times a day. They are good jumpers and some species can jump as high as 30cm.


Beside itchiness, the presence of blood stains due to the excretion of undigested blood by the fleas is a clear sign of fleas in the vicinity.


Because of their blood-sucking behaviour, fleas are a nuisance to human being. Cat flea (Ctenocephalides felis) is the most commonly-found flea. Dog flea (Ctenocephalides canis) and human flea (Pulex irritans) are also commonly-found fleas. They normally bite around the ankles and legs. Their bites are extremely irritating and may result in dermatitis.Some people and animals suffer allergic reactions to flea saliva resulting in rashes. Flea bites generally result in the formation of a slightly-raised swollen itching spot with a single puncture point at the centre. The bites often appear in clusters or lines, and can remain itchy and inflamed for up to several weeks.
Disease Transmitter
Plague disease or Black Death disease had ravaged the countries of Africa, Asia and Europe from time immemorial. On the local front, this disease was first detected in Penang in 1896 and last seen in Perak in 1928, with 207 total recorded cases. In Singapore, 765 cases with 712 deaths were reported in 1933.Plague is basically a disease of wild animals, especially rats and other rodents. It is known as Black Death disease because it causes black spots on the skin. Yersinia pestis will multiply in the intestine and stomach of the flea and block the tract. As the result, the flea always needs to suck blood. The blood containing the plague bacteria is then regurgitated back to the host. In this way, the plague bacteria are transmitted very rapidly. Plague bacteria infect the host lymphatic system which can affect the heart. The bacteria spread rapidly to the lymph nodes and multiply. Without immunisation and medication, death is certain and rapid.
Flea-Borne Typhus

It is known as murine typhus fever. This disease commonly occurs in rat and mice populations. Human can be infected due to exposure to the dried faeces and crushed bodies of fleas. This disease commonly occurs where man and rat are closely associated.


Tapeworm infection is commonly transmitted by fleas. It is transmitted from pets to pets or human who may be infected due to exposure to pets.


An important component of this programme is the cooperation of homeowners in maintaining proper sanitation and continued flea control on their pets.
Inspection of pet lounging areas, garages, below wooden frames, porch area and crawl space, etc.
All possible flea harbourage areas should be treated, including carpeting, other floor areas, pet resting areas, and upholstered areas, with pesticides using ULV foggers.
Customers have to keep their children and pets off sprayed surfaces until they are absolutely dry. This is essential to avoid pesticide-poisoning incidents.
Follow-up treatment and inspection should be done in 10 days’ time to get rid of the newly-hatched adults.


We normally try to squeeze a flea with our fingers. However, this usually does not kill the flea. The best way to kill a flea is to capture it with adhesive tape, crush it between our fingernails, roll it between the fingers, or put it in a fire safe area and burn it with a match or lighter.
The Moche people of ancient Peru worshipped nature. They placed emphasis on animals and even depicted fleas in their art.
Study by the Ohio State University showed that pet owners spend US$1 billion each year to control the flea problem.
In just 30 days, 10 female fleas under ideal conditions can multiply to over a quarter million different life stages.