FLEAS

FLEAS

Fleas are the insects forming the order Siphonaptera. They are wingless, with mouthparts adapted for piercing skin and sucking blood. Fleas are external parasites, living by hematophagy off the blood of mammals and birds.

Some flea species include:

v  Cat flea (Ctenocephalides felis)

v  Dog flea (Ctenocephalides canis)

v  Human flea (Pulex irritans)

v  Moorhen flea (Dasypsyllus gallinulae)

v  Northern rat flea (Nosopsyllus fasciatus)

v  Oriental rat flea (Xenopsylla cheopis)

Over 2,000 species have been described worldwide.

Appearance

A FLEAS

v  Adults small, wingless, about 2.5 mm long.

v  Their bodies are shiny and reddish brown in color.

v  Covered with microscopic hair and are compressed to allow for easy movement through animal fur.

Characteristic and Behavior of Fleas

Fleas are wingless insects (1/16 to 1/8-inch (1.5 to 3.3 mm) long) that are agile, usually dark colored (for example, the reddish-brown of the cat flea), with tube-like mouth-parts adapted to feeding on the blood of their hosts. Their legs are long, the hind pair well adapted for jumping: a flea can jump vertically up to 7 inches (18 cm) and horizontally up to 13 inches (33 cm),[3] making the flea one of the best jumpers of all known animals (relative to body size), second only to the froghopper. If humans had the jumping power of a flea, a 1.8 m (6 ft) person could make a jump 90 m (295 ft) long and 49 m (160 ft) high.

Researchers with the University of Cambridge in England found that fleas take off from their tibiae and tarsi (the insect equivalent of feet) and not their trochantera, or knees. It has been known that fleas do not use direct muscle power but instead use the muscle to store energy in a protein named resilin before releasing it rapidly (like a human using a bow and arrow), with researchers using high-speed video technology and mathematical models to discover where the spring action actually happens.

Their bodies are laterally compressed, permitting easy movement through the hairs or feathers on the host's body (or in the case of humans, under clothing). The flea body is hard, polished, and covered with many hairs and short spines directed backward,which also assist its movements on the host.

The tough body is able to withstand great pressure, likely an adaptation to survive attempts to eliminate them by mashing or scratching. Even hard squeezing between the fingers is normally insufficient to kill a flea. However, rolling them back and forth a dozen times disables their legs, resulting in death.

Fleas lay tiny white oval-shaped eggs better viewed through a loupe or magnifying glass. The larva is small and pale, has bristles covering its worm-like body, lacks eyes, and has mouth-parts adapted to chewing. The larvae feed on various organic matter, especially the feces of mature fleas. The adult flea's diet consists solely of fresh blood. In the pupa phase, the larva is enclosed in a silken, debris-covered cocoon.

Adults are parasites that draw blood from a host. Larvae feed on organic debris, particularly the feces of adult fleas, which contain undigested blood. Fleas commonly prefer to feed on hairy animals such as dogs, cats, rabbits, squirrels, rats, mice and other domesticated or wild animals. Fleas do not have wings, although they are capable of jumping long distances.

FLEAS LIFE CYCLE

Fleas life cycle

Fleas undergo complete metamorphosis. The life cycle, or stages, of the flea is composed of the egg, larval, pupal and adult stages. Cycle length ranges from several weeks to several months and is largely dependent upon environmental conditions.

i) Eggs

The flea life cycle begins when the female lays after feeding. Eggs are laid in batches of up to 20 or so, usually on the host itself, which means that the eggs can easily roll onto the ground. Because of this, areas where the host rests and sleeps become one of the primary habitats of eggs and developing fleas. The eggs take around two days to two weeks to hatch.

ii) Larvae

Flea larvae emerge from the eggs to feed on any available organic material such as dead insects, feces, and vegetable matter. In laboratory studies, some dietary diversity seems necessary for proper larval development. Blood only diets allow only 12% of larvae to mature, whereas blood and yeast or dog chow diets allow almost all larvae to mature. They are blind and avoid sunlight, keeping to dark places like sand, cracks and crevices, and bedding.

iii) Pupae

Given an adequate supply of food, larvae will pupate and weave silken cocoons within 1–2 weeks after 3 larval stages. After another week or two, the adult fleas are fully developed and ready to emerge. They may remain resting during this period until they receive a signal that a host is near - vibrations (including sound), heat, and carbon dioxide are all stimuli indicating the probable presence of a host. Fleas are known to overwinter in the larval or pupal stages.

iv) Adult flea[edit]

Once the flea reaches adulthood, its primary goal is to find blood and then to reproduce. Its total life span can be as short as one year, but may be several years in ideal conditions. Female fleas can lay 5000 or more eggs over their life, allowing for phenomenal growth rates. Average 30–90 days.

A flea might live a year and a half under ideal conditions. These include the right temperature, food supply, and humidity. Generally speaking, an adult flea only lives for 2 or 3 months. Without a host for food a flea's life might be as short as a few days. With ample food supply, the adult flea will often live up to 100 days.

Newly emerged adult fleas live only about one week if a blood meal is not obtained. However, completely developed adult fleas can live for several months without eating, so long as they do not emerge from their puparia. Optimum temperatures for the flea's life cycle are 21 °C to 30 °C (70 °F to 85 °F) and optimum humidity is 70%.

Adult female rabbit fleas, Spilopsyllus cuniculi, can detect the changing levels of cortisol and corticosterone hormones in the rabbit's blood that indicate it is getting close to giving birth. This triggers sexual maturity in the fleas and they start producing eggs. As soon as the baby rabbits are born, the fleas make their way down to them and once on board they start feeding, mating, and laying eggs. After 12 days, the adult fleas make their way back to the mother. They complete this mini-migration every time she gives birth.

Signs of a Fleas

Many signs can indicate flea activity.  A common indication would be pets that repeatedly scratch and groom themselves. This is caused by the discomfort of the flea activity as the adult fleas feed on the pet’s blood. People also may experience bites which leave behind itchy bite marks (a medical doctor can be consulted, since there are other sources of skin irritation beside fleas). Flea dirt, the adult flea feces, also can indicate activity. Flea dirt looks similar to coarse ground black pepper and may be seen in pet beds, carpets, rugs and other areas where the animal host rests.

      Exampleof sign of fleas which is the cat scratch itself. 

Fleas: Detection, treatment, & prevention

Although fleas can be a problem for your pets all year, flea populations typically explode about 5-6 weeks after the weather starts to warm up. So pay special attention to flea prevention in the spring and early summer months.

v  Black specks on your pet or in your dog's bed may be "flea dirt" - the fecal matter from adult fleas. There are two easy ways to check for black specks:
Run a flea comb over your pet, making sure the comb reaches the skin through the coat. If black specks are on the comb when you pull it off, they might be flea dirt. If fleas are on the comb, drown them in a bowl of soapy water before they can get away or jump back on your pet. You can get a flea comb from your vet or pet retailer. Metal ones are the best.
Place a white paper towel beneath your pet and rub your hands across its fur. If black specks appear on the towel, it may be flea dirt.

v  If infested with fleas, your pet may become very nervous, annoyed and may scratch excessively.

v  When you discover fleas on your pet, your home is probably already part of the problem. There will be eggs, larvae, and pupae wherever your dogs like to lie around or sit.

Health problems

In addition to extreme discomfort, fleas and ticks can also cause serious health problems in pets and people.

v  When a flea bites your dog, it deposits a small amount of saliva in the skin. Your dog can develop Flea Allergy Dermatitis (FAD) in reaction to this saliva, which causes severe itching. In addition to your pet scratching or biting excessively around the tail, groin or backside, scabs or bumps may also appear on your pet's neck or back.

v  Anemia may occur in pets if too many fleas suck their blood. The signs of anemia include pale gums, weakness and lethargy in your pet.

v  Dogs may become infected with tapeworms by ingesting an infected flea. Pets may have intense anal itching, and tapeworm segments may be seen around the anal area or in the feces.

Treating flea infestation

There are four main ways to treat a flea infestation:

v  Kill adult fleas that are already on the pet.

v  Kill newly-arriving adult fleas on the pet. It may take three or four months to kill all the fleas emerging from pupae in the household environment.

v  Prevent further infestation of the home by using an Insect Growth Regulator (IGR) to inhibit the hatching of viable flea eggs and prevent the development of larvae into adult fleas.

v  Clear the home and the environment of flea eggs, larvae, and pupae that are already there.

You can achieve the first three by treating your pet regularly with a product that contains two active ingredients such as FRONTLINE® Plus (one to kill adult fleas, the other to prevent the development of eggs and larvae.)

Flea pupae are protected by their cocoons - all pupae will have to hatch out and be killed as adult fleas on the pet. It can take several weeks for all pupae to hatch from an infested environment. If undisturbed, pupae can exist for many months in the environment, which is why encouraging them to hatch (by allowing your pets to roam their usual haunts) and regular flea treatment are important in helping to rid a home of an infestation.

Be sure to treat all dogs and cats. Some dogs and cats are good at masking the signs of a flea infestation. But if one pet is infested, all pets in the household can be.

Prevention

In addition to applying FRONTLINE Plus, the following steps can also be taken to prevent fleas from infesting your pet:

v  Frequently vacuum the areas your pet is around, especially carpeted areas in your home, any furniture that is frequented by your pet, and in your car (if your pet rides in your car). This will clean up as many immature fleas (eggs, larvae and pupae) as possible.

v  Regularly wash your pet's bedding, blanket and other washable items in the hottest water possible (check the laundering instructions to make sure that washing in hot water isn't a problem).

v  Keep your yard neat. Mow your lawn and rake up any leaves, brush or clippings.

v  Periodically hang door mats, rugs and other non-washable items in direct sunlight.

             Method to treating fleas infection 

More information about Fleas

Can fleas fly?

Fleas do not fly and are wingless as adults. Their preferred method of movement is for the adults to jump onto a host when that animal passes close by. Flea larvae are mobile and will move slowly from one location to another by crawling. The main reasons flea larvae move are to locate food and a protective, shaded, moist location that is favorable to the flea larvae’s survival.

Do fleas carry disease?

Yes, fleas can transmit diseases when taking a blood meal from a host or via contaminated fecal pellets. Some flea-borne diseases include:

v  Plague – transmitted by the Oriental rat flea

v  Flea-borne typhus, also known as murine typhus – transmitted by the bacteria-infested feces of infected cat fleas when they enter the body at the time of the flea’s bite or from scratching the area of the bite.

v  Bartonellosis –Oriental rat flea and cat flea bites may transmit cat scratch disease.

v  Flea tapeworm – can be transmitted if children accidently eat an infected flea or contact infected feces.

v  Tungiasis – a tropical area ailment that is caused by the chigoe flea (Tunga penetrans) when it burrows into the skin and takes a blood meal. As the adult female feeds, she grows larger due to the development of her eggs. The bite of the chigoe flea often results in secondary infections and itching.

References :

 i) http://en.wikipedia.org/wiki/Flea

 ii)http://www.orkin.com/other/fleas/

 iii)http://www.cesarsway.com/tips/fleasandticks/fleas-detection-treatment-and-prevention