Chapter 6 - Fleas, Lice, Ticks and Mites

Fleas, Lice, Ticks and Mites

Fleas

Fun Facts About Fleas

• Wingless but very good in jumping. Up to 7 inches
• Have a mouthparts for piercing skin and sucking blood
• External parasites, living by hematophagy of the blood of mammals and birds
• Usually and dark colored
• Fleas do not use direct muscle power but instead use the muscle to store energy in a protein name resilin before releasing it rapidly.
• Their bodies are laterally compressed, permitting easy movement through the hairs or feather  on the host's body.
• The flea body is hard, polished and covered with many hairs and short spines directed backwards, which also assist it's  movements on the host. 
• By rolling them back and forth a dozen times disables their legs, resulting in death.

Types of Fleas

• Cat flea (Ctenocephalides felis)
• Dog flea (Ctenocephalides canis)
• Human flea (Pulex irritans)
• Moorhen flea (Dasypsyllus gallinulae)
• Northern rat flea (Nosopsyllus fasciatus)
• Oriental rat flea (Xenopsylla cheopis)

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.

Larvae

• Flea larvae emerge from the eggs to feed on any available organic material such as dead insects, feces, and vegetable matter. 
• . 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.

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.

Adult flea

• 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

•  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). 
• 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

Prevention

• Flea bites can be treated with anti-itch creams, usually antihistamines hydrocortisone Calamine lotion has been shown to be effective for itching.
• 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.
• Applied flea repellant powder on your pet
• Combatting
• Fogger or use insecticide
• Frequent vacuuming inside home.
• Bathing.
• Baking soda are used to kill fleas via dehydration.
• Fleas cannot withstand high temperatures, so a turn through the dryer on medium or high will kill the fleas.
  To collect living fleas from a room or space, eliminate lighting as much as possible while focusing a single source of light just above the floor and directing the light downward.
• Lower temperatures slow down or completely interrupt the flea life-cycle. Fleas thrive at higher temperatures, but need 21° to 32 °C (70° to 90 °F) to survive.

Lice

• Lice are tiny, wingless, 
• Parasitic insects that feed on your blood. 
• Lice are easily spread- especially by schoolchildren, through close personal contact and by sharing belongings.
• Lice are tiny insects that live on humans and feed on blood. When a large number of lice live and multiply on a person, it is called an infestation.

Life Cycle of Lice

• The life cycle of the head louse has three stages: egg, nymph, and adult.

• Eggs - Nits are head lice eggs. They are hard to see and are often confused for dandruff or hair spray droplets. Nits are laid by the adult female and are cemented at the base of the hair shaft nearest the scalp. They are 0.8 mm by 0.3 mm, oval and usually yellow to white. Nits take about 1 week to hatch (range 6 to 9 days). Viable eggs are usually located within 6 mm of the scalp.

• Nymphs - The egg hatches to release a nymph.The nit shell then becomes a more visible dull yellow and remains attached to the hair shaft. The nymph looks like an adult head louse, but is about the size of a pinhead. Nymphs mature after three molts and become adults about 7 days after hatching.

• Adults - The adult louse is about the size of a sesame seed, has 6 legs (each with claws), and is tan to grayish-white. In persons with dark hair, the adult louse will appear darker. Females are usually larger than males and can lay up to 8 nits per day. Adult lice can live up to 30 days on a person’s head. To live, adult lice need to feed on blood several times daily. Without blood meals, the louse will die within 1 to 2 days off the host.

Several types of lice exist and transmission: 

• Lice spread easily from one person to another through close contact or through shared clothing or personal items (such as hats or hairbrushes). A louse cannot jump or fly.
• Head lice. These lice develop on your scalp. They're easiest to see at the nape of your neck and over your ears.
• Body lice. These lice live in clothing and on bedding and move onto your skin to feed. Body lice most often affect people who aren't able to bathe or launder clothing regularly, such as homeless or transient individuals.
• Pubic lice. Commonly called crabs, these lice occur on the skin and hair of your pubic area and, less frequently, on coarse body hair, such as chest hair, eyebrows or eyelashes.
• Frequent scratching can cause a skin infection. In the most severe cases of head lice, hair may fall out, and the skin may get darker in the areas infested with lice.

Symptoms

• Head lice may not cause any symptoms at first. Itching on the scalp may start weeks or even months after lice have started to spread. Scratching can make the skin raw. The raw skin may ooze clear fluid or crust over, and it may get infected.
• Pubic lice cause severe itching. Their bites may cause small marks that look like bruises on the torso, thighs, or upper arms. If pubic lice get on the eyelashes, the edges of the eyelids may be crusted. You may see lice and their eggs at the base of the eyelashes.
• Body lice cause very bad itching, especially at night. Itchy sores appear in the armpits and on the waist, torso, and other areas where the seams of clothes press against the skin. The lice and eggs may be found in the seams of the person's clothing but are typically not seen on the skin.

Treatment for Lice

• A doctor can usually tell if you have lice by looking closely for live lice or eggs in your hair. The doctor may also comb through your hair with a fine-toothed comb to help detect lice. He or she may look at the lice or eggs under a microscope.
• Your doctor can also find pubic lice and body lice by looking closely at your body or your clothing.
• Lice won't go away on their own. Be sure to do all you can to treat lice and to prevent the spread of lice.
• The most common treatment is an over-the-counter or prescription cream, lotion, or shampoo. You put it on the skin or scalp to kill the lice and eggs. In some cases, you may need treatment a second time to make sure that all the eggs are dead. If two or more treatments don't work, your doctor may prescribe a different medicine.
• It's also important to wash clothing and bedding in hot water to help get rid of lice.
• Some people continue to have itching for 7 to 10 days after the lice and eggs have been killed. Steroid creams or calamine lotion can relieve the itching. 

Ticks

• Are small arachnids in the order Parasitiformes.

• Along with mites, they constitute the subclass Acarina. 

• Ticks are ectoparasites(external parasites), living by hematophagy on the blood of mammals, birds, and sometimes reptiles and amphibians. 

• Are vectors of a number of diseases, including Lyme disease, Q fever (rare; more commonly transmitted by infected excreta),Colorado tick fever,Rocky Mountain spotted fever, African tick bite fever, Crimean Congo hemorrhagic fever, tularemia, tick-borne relapsing fever, babesiosis,ehrlichiosis, and tick-borne meningoencephalitis, as well as bovine anaplasmosis and probably the Heartland virus. 

• Some species, notably the Australian paralysis tick, are also intrinsically venomous and can cause paralysis.

Habitats

• Tick species are widely distributed around the world, but they tend to flourish more in countries with warm, humid climates, because they require a certain amount of moisture in the air to undergo metamorphosis, and because low temperatures inhibit their development from egg to larva.

• Ticks  are especially common and varied in tropical countries, where they cause considerable harm to livestock by transmission of many species of pathogens and also causing direct parasitic damage.

• For an ecosystem to support ticks, it must satisfy two requirements: The population density of host species in the area must be high enough, and Humidity must be high enough for ticks to remain hydrated. 

• Another certain features of microclimate such as sandy oil, hardwood trees,river and the presence of deer were determined to be good predictors of dense tick populations.

• Ticks satisfy withall the nutritional requirement asectoparasites, feeding on a diet of blood in a practice known as hematophagy, They are unable to find a host to feed will die.

• Ticks extract the blood by cutting a hole in the host's epidermis, into which they insert their hypostome, in order to keep the blood from clotting by excreting an anticoagulant andpreparing to feed will take from ten minutes to two hours.

• Ticks find their hosts by detecting animal's breadth and body odors, or by sensing body heat, moisture and vibrations. They are incapable of flying or jumping, but many tick species wait in a position known as "questing". While questing, ticks hold on to leaves and grass by their third and fourth pair of legs. They hold the first pair of legs outstretched, waiting to climb on to the host. When a host brushes the spot where a tick is waiting, it quickly climbs onto the host. 

• Some ticks will attach quickly while others will wander looking for thinner skin like the ear. Depending on the species and the life stage, preparing to feed can take from ten minutes to two hours. On locating a suitable feeding spot, the tick grasps the skin and cuts into the surface.

How to differentiate ticks

• Like all arachnids, adult ticks have eight legs. 

• The legs of Ixodidae and Argasidae are similar in structure. Each leg is composed of six segments: the coxa, trochanter, femur, patella, tibia, and tarsus. 

• Each of these segments is connected by muscles which allow for flexion and extension, but the coxae have limited lateral movement.

• When not being used for walking, the legs remain tightly folded against the body.
• Larval ticks hatch with six legs, acquiring the other two after a blood meal and molting into the nymph stage.

• In addition to be being used for locomotion, the tarsus of leg 1 contain a unique sensory organ, the Haller's organ, which can detecht odors and chemicals emanating from the host, as well as sensing changes in temperature and air current.

How can ticks survive?

• After hatching from the eggs, ticks must eat blood at every stage to survive. Ticks require this many hosts can take up to 3 years to complete their full life cycle, and most will die because they don't find a host for their next feeding.

• They can feed on animals, birds, reptiles and amphibians.

• Most ticks prefer to have a different host animals at each stage of their life.

How do ticks transmit disease?

Ticks transmit pathogens that cause disease through the process of feeding.

• Depending on the tick species and its stage of life, preparing to feed can take from 10 minutes to 2 hours. When the tick finds a feeding spot, it grasps the skin and cuts into the surface.

• The tick then inserts its feeding tube. Many species also secrete a cement-like substance that keeps them firmly attached during the meal. The feeding tube can have barbs which help keep the tick in place.

• Ticks also can secrete small amounts of saliva with anesthetic properties so that the animal or person can't feel that the tick has attached itself. If the tick is in a sheltered spot, it can go unnoticed.

• A tick will suck the blood slowly for several days. If the host animal has a bloodborne infection, the tick will ingest the pathogens with the blood.

• Small amounts of saliva from the tick may also enter the skin of the host animal during the feeding process. If the tick contains a pathogen, the organism may be transmitted to the host animal in this way.

• After feeding, most ticks will drop off and prepare for the next life stage. At its next feeding, it can then transmit an acquired disease to the new host.

Prevention from Ticks

• Avoid wooded and bushy area with high grass and leaf litter.
• Walk in the center of trail.
• Use repellent.
• Take bath or shower as soon as possible after coming indoor.
• Parental checking towards children on their body.
• Examine gear and pets.
• Check your pets for ticks daily,especially after they spend time outdoors.
• Ask your veterinarian to conduct a tick check at each exam.
• Reduce ticks habitat in your yard.
• Take preventive measures against ticks year-round, be extra vigilant in warmer months (April-September) when ticks are most active.

Mites

What are  mites?

• Mites are microscopic insect-like creatures that cannot be seen by the naked eye.

• Identified by the fact that the adults have eight legs and the body is a whole unit, not made up of segments.

• There are several different kinds of itch mites in the United States. One type, the oak leaf gall mite, is believed to be responsible for outbreaks of human bites in 2004 in Kansas, Missouri, Nebraska and Texas.

• The colour is completely dependent on what the mites have been eating. This can vary from dark red, to purple, to light yellow. With thrips and whitefly as prey, the colour tends to be a kind of light orange. It is also difficult to tell from its behaviour which predatory mite you are dealing with.

• The mite feeds on the larvae of a small fly (midge) which forms a brown and crusty shell on the edge of an oak leaf (known as a gall)

• Predatory mites cannot fly and their mobility is therefore limited. 

Can people be bitten by itch mites?            

Yes. Although the oak leaf gall mite feeds on midge larvae, they can accidentally bite people when looking for food. Mites usually need about four hours on your body before they bite. Once the mite’s regular food source is gone from the leaves, usually in late summer, the mites drop from the trees. Oak leaf gall mites are so small that they can float on the wind, and pass through window or door screens and loosely-woven clothing.

Presence of Mites

• Red welt that look like chigger bites on your neck, face,arms, and upper body
• Itching on body.
• Watery eyes
• Runny nose
• Sneezing

You may develop red welts that look like chigger bites on your neck, face, arms and upper body. These bites are not usually on legs where chigger bites may be found. The itch mite welts form into a pimple-like lesion after about 12 hours. The bites are very itchy and can be present for up to two weeks.