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Parasitic Insect Treatment Articles

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Parasitic Insects

Parasitic insects are very important ecologically, medically and economically. A broad definition of parasitic that includes mosquitoes and biting flies would make some 15% of insects parasitic.

Lice have been a part of human history as parasites without socioeconomic boundries. Archaeologists have even found traces of lice on mummies. These insects are wingless, flattened and have reduced or no eyes. The eggs (nits) are glued to the feathers or hairs of the host and there are three immature forms from egg to adult. There are no free living stages and they die when separated from the host.


Bed bugs
Bugs of the Family Cimicidae are reddish brown, dosoventrally flattened bugs that are rather large (up to 8 mm long) with no wings. They are nocturnal feeders that run very fast. They generally are most active around dawn when they feed on resting hosts. Daytime hiding places include mattress seams or crack in walls or furniture. The bites may cause allergic reactions in some people but generally cause little reaction. Domestic cleanliness and residual insecticides to hiding places is effective in controlling bed bugs.

Reduvid Bugs
These bugs are vectors for Trypanosoma cruzi. These are large winged bugs that live in cracks and crevices of poorly constructed homes or in thatched roofs. They are not picky about the source of their blood meal and will feed on whatever is available in the habitat. Improvements in construction methods, the use of metal rather than thatched roofs and residual insecticides are effective control measures.

Of the some 2,000 flea species, most are parasites of mammals. Historically fleas have had a great impact as transmitters of the bacteria (Yersinia pestis) that causes the plague. Fleas are bilaterally flattened, commonly reddish black, and wingless. The adults feed by sucking blood from the host. The larvae feed on debris and flea droppings on the bedding. Fleas are amazing jumpers. For example, common fleas can jump some 33 cm high. The oriental rat flea can jump more than 100 times its body length.


Fleas are not host specific but have preferred hosts. Pulex irritans is the human flea but can be found on dogs, cats, squirrels, pigs, and others. This species can transmit the plague. Ctenocephalides canis and C. felis are the common dog and cat fleas, respectively. Controlling pet parasites can be accomplished by numerous commercially available residual, topical and systemic insecticides.



Flies (Order Diptera) represent the most medically important group of insects. They cause directly or indirectly a million human deaths each year. Some flies do not kill but contribute to disfiguring, debillitating diseases of many kinds either as vectors of pathogenic organisms or as parasites.


Black Flies
Black flies belong to the family Simuliidae and are found worldwide where the females feed on blood as well as plant nectar. Black flies are the vectors of Onchocerca volvulus. Mating occurs in flight, larval development occurs in running water and the flies are therefore numerous near rivers and streams. In the US and Canada, S. venustum are well known to fishermen and campers. Bites may produce little reaction in some people, but often small red itching wheals develop as a local reaction. Sometimes black fly fever can result which is characterized by nausea, headache, fever and swollen limbs.

Sand flies
Most sand flies do not affect humans, but rather parasitize reptiles and amphibians. However, some do feed on birds and mammals, including humans. Females take a blood meal in addition to plant fluids. Males eat only plant juices. Most are night time feeders due to the need to avoid hot desiccating environments. They are good vectors of disease and participate in leismaniasis, bartonellosis and some viral diseases.

Biting midges (no-see-ums)
These very small flies (less than 1 mm) are mostly daytime feeders that are most obnoxious on calm days as winds easily carry them away. Only females feed on blood. They act as vectors for various protozoal and viral disease of domestic animals.

Some 300 species of mosquitoes have been described with at least 150 of these being in N. America. The life cycle of mosquitos requires water for the larval and pupal stages. Adult females can live for 4-5 months but during the height of the summer season they may only live a couple weeks. Males may live only for weeks to a month. Species of mosquito transmit western equine encephalitis, St. Louis encephalitis, filarial worms, yellow fever, dengue fever, eastern encephalitis and malaria.

Tsetse flies
These flies of the Glossina species are found in Africa where they are vectors of sleeping sickenss. They are daytme feeders that are visually attracted to moving objects. Both sexes feed exclusively on blood, including that of humans.

These epidermal parasites are found in nearly every country in the world. Their importance as agents and vectors of disease has long been recognized. Pathogenesis appears in several ways including anemia, dermatosis, paralysis and infections. Ticks transmit viruses, bacteria, protozoa, filaria, richettsias and spirochettes.

Follicle mites of humans live in hair follicles or sebaceous glands of the face. The incidence of these parasites is very high in the eldery but can be seen in young adults as well. Infection is usually benign but follicle mites have been suspected in the causation of some acne by introducing bacteria into the follicles. The dog follicle mite causes mange which can be seriously pathogenic and even lethal. The skin develops reddish pimples, becoming hot and thickened with an obnoxious exudate. Treatment can be difficult and sometimes infected puppies must be killed. In adult dogs treatment is usually successful and sometimes acquired immunity results in a decrease in symptoms and even no further signs of disease.


Scabies or sarcoptic mange results from infestation by the itch mite. The females burrow rapidly into the skin after mating and lay eggs in tunnels within the epidermis of the skin for about 2 months. Eggs hatch and make their way to the surface of the skin. The tunneling and secretions of the mites cause severe itching in infected persons. Transmission occurs usually by physical contact between infected persons.


Chiggers and dust mites also belong to this group of insects. Chiggers can cause an ithcy rash on the skin. Dust mite allergies are caused when mites, parts of mites or their excrement are inhaled by sensitive persons.


Facts of Lice

by Marcy McQuillan, Nitless Noggins

Email Marcy for help!

What are head lice?

The head louse, or Pediculus humanus capitis, is a parasitic insect that can be found on the head and, more rarely, the eyebrows and eyelashes of people. Head lice feed on human blood several times a day and live close to the scalp to maintain their body temperature.

What are the symptoms of head lice?

* An itchy scalp
* A tickling feeling of something moving on the scalp or through the hair
* Red bite marks on the scalp caused by excessive scratching or a red rash on the back of neck


Detection and Diagnosis of Lice

Head lice and eggs are found almost exclusively on human head hair and the scalp, frequently around and behind the ears and near the neckline at the back of the head. Head lice and eggs are sometimes also found on the eyelashes or eyebrows, but this is uncommon. Misdiagnosis of head lice is common.


The best diagnosis is by finding a live nymph or adult louse on the scalp or hair of a person. Adult and nymphal lice are very small, move quickly, and avoid light, so they may be difficult to find. Using a fine toothed louse comb helps in correctly diagnosing head lice.

How They Spread

These critters move from head to head, hat to head, pillow to head, comb to head...If it's been on someone's lice ridden noggin, it could very well be a source of infestation.


Why shampoos don't work


Rid and other lice shampoos only kill adult lice and adolescent newts. These shampoos work by attacking the bug's central nervous system. Because baby lice or "nymphs" have not yet developed a central nervous system, they cannot be killed. In addition, lice shampoos do not kill lice eggs or "nits". So while you may kill the adult bugs, their eggs will remain, only to hatch a few days later starting the cycle all over again. This is why lice are so hard to eliminate! In addition, lice shampoos contain toxic chemicals which can enter your system through the skin on your scalp. Many adult lice have become resistant to these chemicals. So in many cases, the shampoos are completely useless




Twenty-four hours after mating, the female head louse lays her eggs, more commonly referred to as "nit." Under optimum conditions, a healthy female will lay approximately 140 eggs during her lifetime of about 30 days. The eggs are coated with a fixative that cements them to the hair shaft. Because the chemical structure of this fixative substance is very similar to that of the hair shaft, researchers have yet to develop a product that will dissolve the fixative without damaging the hair.


Like many ectoparasites (external parasites) that can endure starvation and extremes of temperature, lice and their eggs can survive only under relatively narrow set of environmental conditions. From their first blood meal to their last, head lice prefer to feed every four to six hours and cannot survive if they miss several consecutive meals. Therefore, although a louse may fall or climb onto other surfaces, it cannot live on these and must return to a human head within 24 hours if it is to survive.


Newly-laid viable eggs are plump and shiny and have a tan or coffee color. Eggs that have hatched are clear, white, or light in color and may appear shrunken or indented. On the end of the nit facing away form the scalp is the "operculum," a tiny cap with several holes in it that allow air and moisture into the egg for the development of the embryo.


After a 7 to 10 day incubation period, the baby louse, commonly referred to as a "nymph" or "instar," uses its mouth parts to cut a hole in the operculum. The nymph then sucks in air and rapidly expels it, causing the operculum to pop off. The newly-emerged nymph closely resembles an adult louse but is much smaller and not yet capable of reproducing. It is flesh-colored and no larger than a pinhead, making it almost impossible to see with the naked eye. The nymph emerges, effective and mobile, and must feed on human blood shortly after hatching or it will rapidly succumb to dehydration and starvation.


The scalp should be examined in sunlight or under bright artificial light. The hair should be parted, with individual stands checked for nits. Magnifying reading glasses (2x or greater) available in pharmacies can aid in visual detection. Nits are most predictably found on hairs at the nape of the neck and behind the ears, where they are protected from extremes of light and temperature. However, they may be laid anywhere on the hair, especially in warm weather.


The appearance of a nit is often confused with that of a flake of dandruff or a dried particle of hairspray or gel. A distinguishing feature is that dandruff and hair products can be easily combed off the hair or removed with the fingers, while nits cannot. Nits are firmly glued to the hair and must be removed with a fine-toothed comb or fingernails, or snipped off with scissors.


Common measures to mechanically remove lice and nits from the hair, such as brushing, combing with a good nit comb, shampooing, and towel or blow-drying, play a role in reducing the number of viable lice and eggs on the head, but are insufficient to cure an active infestation. Treating head lice effectively involves the manual removal of nits and lice with combing, nit picking, and/or the controlled heated air produced by the LouseBusterTM device.


It is common practice to comb or "nit pick" through the hair after treatment to remove lice and nits. Nit removal is important because it removes an outwardly visible sign of head lice infestation, thus preventing stigmatization.


Many school officials insist on a "no nit" policy to ensure the freedom from infestation and proof of adequate treatment. Because this policy fails to differentiate between viable and non-viable nits, it tends to have an overreacting effect, keeping children who pose no threat of transmitting head lice from attending school. The "no nit" policy also places a substantial burden on parents, who must go through the time-consuming process of removing all nits from the hair. For many working parents, this many mean missing considerable time from work.


Reluctant to continue applying pesticides to children's heads, many desperate and frustrated parents and health professional are turning to alternative therapies to battle head lice. Many individuals claim to have successfully cured their infestations by using inexpensive, non-pesticide products including petroleum jelly, hair pomade, olive oil, mayonnaise, vegetable shortening, vinegar, mineral oil, and essential oils sold at health food stores.


There is no doubt that oily alternatives such as petroleum jelly, olive oil, or mayonnaise slow down the lice, making them easier to find and comb out, and even killing some. Unfortunately, because they are not as effective as the currently available pediculicide products, they usually require repeated overnight treatments and many hours of painstaking combing. The need for repeated overnight treatments, in turn, can delay a child's return to school.

Nitless Noggins has significant experience with many different types of head lice treatment options.

Contact us today and let us take the worry and hassle out of your head lice problem. We work quickly and discretely and all our services are 100% guaranteed.


What does head lice look like? Head lice have a life cycle with three stages

(Icons/Graphics) Nit_Stage1_Egg.jpg These are lice eggs laid by the adult female louse at the base of the hair shaft near the scalp. The eggs are firmly attached to the hair shaft and are oval-shaped and very small and hard to see. Eggs vary in color from clear to light brown to yellowish-white. They are often confused with dandruff, scabs, or hair spray droplets. Eggs are usually located no more than 1/4in (.635cm) from the base of the hair shaft. Eggs usually take about 8-9 days to hatch.



(Icons/Graphics) Nit_Stage3_Adult.jpg A nymph is the immature louse that has recently hatched from the egg. Nymphs look like adult lice, but are smaller. Like adult lice, nymphs must feed regularly on human blood.
Nymphs mature into adults about 9-12 days after hatching from the egg.




(Icons/Graphics) Nit_Stage3_Adult.jpg The fully grown adult louse is about the size of a sesame seed, has six legs, and is tan to grayish-white in color. To survive, adult lice must feed on blood. An adult head louse can live about 30 days on a person's head, but will die within 24-48 hours if it falls off a person.


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