Invertebrata

Invertebrata Nemathoda

S M A N 1

Oleh Amirur Rozak Monica Sani T. Rizki Marudur S. Nitya Wulandari Rezeki suci M.

T E G A L

Identification 5 kingdom KINGDOM / REGNUM

- The basis classification used by taxonomist is the similarities and differences in characteristics of morphology, physiology, and anatomy. The group of organism found from the result of classification are called taxon. The taxon formation is regularly gradded. Each taxon level is given a certain name. The classification level from the highest level (kingdom) until the lowest level (spesies) are as follow.

PHYLUM / DIVISI

CLASS

ORDO

FAMILIA

GENUS

SPESIES

KINGDOM Kingdom is the biggest group of living organism known by biologist. Classification system which now still used is the classification of 5 kingdom which purposed by R.H. Whittaker, that is monera, prostist, fungi, plantae, and animalia. Classification 5 kingdoms is based on cell type, uncelluler or multicelluler, and nutrition type. - Animalia kingdom animal are the group of eukaryotic organisms from the kingdom of animalia which have multicelluler property, have the ability to move from one place to another, and heterotrop. Different from the plant, all of animals can move the parts of their body and have ability to move their body. Animal reproduce by sexual or asexual way. Sexual can happen if egg cell meet sperm to form zygote. While asexual reproduction happens by everal method, such as fragmentation, binnary fission, and budding formation. - The kingdom of animal consist nine phylum, that is: 1. Porifera 2. Cnidaria 3. Platyhelminthes 4. Nematelminthes 5. Annelida 6. Mollusca 7. Antrophoda 8. Echinodermata 9. Chordata - Animal kingdom are divided into two group based on presence or absence of backbone, that is 1. Vertebrata (have backbone) 2. Invertebrata (doesn’t have backbone)

Invertebrata Invertebrate is the group of animal which has no backbone. The number of member is about 98% of entire animal kingdom. In the food chain, Invertebrate have a role as primary and secondary consumer also decomposer. Invertebrate occupy all of habitat in earth surface. The living method of Invertebrate are solitary or make colony. Some are sedentary (live one place) or attach a substrate and some move. Invertebrate reproduce by asexual and sexual. Asexual reproduction happens with dividing itself, budding and partenogenesis. While sexual reproduction by fertilization of male gamet and female gamete. There are several ways to divided invertebrata into different main types or phyla: 1. According to the true body tissue - Parazoa : have no tissue (porifera) - Eumetazoa : have true tissue (Cnidaria, Platyhelminthes, Nematelminthes, Annelida, Mollusca, Echinodermata, and Antrophoda) 2. According to the overall pattern of body form - Asymmetry (antrophoda) - Radial symmetry (porifera) - Bilateral symmetry (Nematelminthes) 3. According the body cavity - Acoelomate - Pseudocoelomate (Nematelminthes) - coelomate

Nematelmint hes

References 

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A. M. A. Aguinaldo, J. M. Turbeville, L. S. Linford, M. C. Rivera, J. R. Garey, R. A. Raff, & J. A. Lake, 1997. Evidence for a clade of nematodes, arthropods and other moulting animals. Nature 387: 489-493. R. Buchsbaum, M. Buchsbaum, J. Pearse, & V. Pearse, 1987. Animals Without Backbones. Chicago: University of Chicago Press. T. I. Storer, R. L. Usinger, R. C. Stebbins, & J. W. Nybakken, 1979. General Zoology, 6th edition. New York: McGraw-Hill Book Company. Wallace, Robert Lee, Claudia Ricci, & Giulio Melone, 1996. A cladistic analysis of pseudocoelomate (aschelminth) morphology. Invertebrate Biology 115(2): 104-112. Tree of Life Web Project (ToL) (2002b): Nematoda. Version of 2002-JAN-01. Retrieved 2008NOV-02. Baird JK, Mistrey M, Pimsler M, Connor DH (March 1986). "Fatal human ascariasis following secondary massive infection". Am. J. Trop. Med. Hyg. 35 (2): 314–8. PMID 3953945 http: en/wikipedia.com/wiki/nematoda Hotez PJ, Pritchard DI (June 1995). "Hookworm infection". Sci. Am. 272 (6): 68–74. PMID 7761817 "Pinworm". Encyclopædia Britannica. http://www.britannica.com/EBchecked/topic/461262/pinworm. Retrieved on 2009-04-08.

NEMATHODE NEMATHODE INTRODUCTION INTRODUCTION

CLASSIFICATION CLASSIFICATION

CHARACTERISTIC CHARACTERISTIC

LIVINGENVIRONMENT ENVIRONMENT LIVING

WAYOF OFLIVE LIVE WAY

REPRODUCTION REPRODUCTION

MEMBEROF OFNEMATHODA NEMATHODA MEMBER

BENEFITAND ANDLOSS LOSS BENEFIT

NUTRITION NUTRITION

MORPHOLOGY MORPHOLOGY

CONCLUSION CONCLUSION

Introduction The "roundworms" or "nematodes" (phylum Nematoda) are the most diverse phylum of pseudocoelomates, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 80,000 have been described, of which over 15,000 are parasitic. It has been estimated that the total number of described and undescribed roundworms might be more than 500,000. Unlike cnidarians or flatworms, roundworms have a digestive system that is like a tube at both ends. Nematodes have successfully adapted to nearly every ecological niche from marine to fresh water, from the polar regions to the tropics, as well as the highest to the lowest of elevations. They are ubiquitous in freshwater, marine, and terrestrial environments, where they often outnumber other animals in both individual and species counts, and are found in locations as diverse as Antarctica and oceanic trenches. They represent, for example, 90% of all life on the seafloor of the Earth. The many parasitic forms include pathogens in most plants, animals, and also in humans

Classification Phylum

Class

Order

Nematoda Adenophorea Enoplida Isolaimida Mononchida Dorylaimida Trichocephalida Mermithida Muspiceida Araeolaimida Chromadorida Desmoscolecida Desmodorida Monhysterida Secernentea Rhabdita Strongylida Ascaridida Spirurida Camallanida Diplogasterida Tylenchida Aphelenchida

Nematode systematics Due to the lack of knowledge regarding many nematodes, their systematics is contentious. Traditionally, they are divided into two classes, the Adenophorea and the Secernentea, and initial DNA sequence studies suggested the existence of five clades: Dorylaimida Enoplida Spirurida Tylenchida Rhabdita As it seems, the Secernentea are indeed a natural group of closest relatives. But the "Adenophorea" appear to be a paraphyletic assemblage of roundworms simply retaining a good number of ancestral traits. The Enoplida do not seem to be monophyletic either but to contain two distinct lineages. The old group "Chromadoria" seem to be another paraphyletic assemblage, with the Monhysterida representing a very ancient minor group of nematodes. Among the Secernentea, the Diplogasteria may need to be united with the Rhabdita. while the Tylenchida might be paraphyletic with the Rhabdita.

• Adenophorea Adenophorea is a class of nematodes. They are unsegmented worms. Characteristics of adenophorea are: •amphids always post-labial, variable shape, pore-like to elaborate •deirids are not seen •phasmids are generally absent •hypodermal glands resent (excretory) uninucleate •simple non-tubular excretory system when present •three caudal glands commonly opening through a spinneret at the tail tip •male generally has two testes •caudal alae are rare •male with supplement glands in a single ventro-median row •sensory papillae in cephalic region and along the body •generally there are five esophageal glands •marine, freshwater, terrestrial

Example

Mononchidae

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Secernentea

Secernentea are the main class of nematodes, characterised by numerous and an excretory system possessing lateral canals. Like all nematodes, they have no circulatory or respiratory system. The Secernentea contain several significant parasitic species among the Rhabditia and Spiruria. Caenorhabditis elegans, the famous laboratory animal, is one of the many harmless members of the Rhabditia. Systematics Subclasses and orders of Secernentea are: - Subclass Rhabditia (paraphyletic?)  Rhabditida  Strongylida - Subclass Spiruria  Ascaridida  Camallanida (sometimes included in Spirurida)  (sometimes included in Spirurida)  Oxyurida  (formerly in Tylenchida)  Spirurida - Subclass Diplogasteria (may belong in Rhabdita)  Diplogasterida - Subclass (may belong in Rhabdita)  Aphelenchida  Tylenchida - Order incertae sedis

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Example

Ancylostoma caninum – a hookworm attached to the intestine of a dog, though species of hookworm infect other mammals including humans. The name comes from them being bent over at the head end so forming a hook.

Characteristic Characteristics of Nematode: 1)Bilaterally symmetrical, and vermiform. 2)Body has more than two cell layers, tissues and organs. 3)Body cavity is a pseudocoel, body fluid under high pressure. 4)Body possesses a through gut with a subterminal anus. 5)Body covered in a complex cuticle. 6)Has a nervous system with pharyngeal nerve ring. 7)Has no circulatory system (no blood system) 8)Reproduction normally sexual and gonochoristic (internal fertilization). 9)Live just about everywhere, many species are endoparasites

Living environment

Mostly, nemathode live at sediment layers in water (both marine water and fresh water), and are abundant soil

Nutrition

Nematodes normally eat bacteria, fungi and protozoans, although some are filter feeders. Excretion happens through a separate excretory pore. Nematodes also contract bacterial infections within excretion pores.

Way of live 1. Herbivores. These are the plant parasites, which are relatively well known. This group includes many members of the order Tylenchida, as well as a few genera in the orders Aphelenchida and Dorylaimida. The mouthpart is a needlelike stylet which is used to puncture cells during feeding. Ectoparasites remain in the soil and feed at the root surface. Endoparasites enter roots and can live and feed within the root. .

In the herbivore, the mouthpart is modified into a stylet for puncturing plant cells.

In the bacterivore, the mouth or stoma is a hollow tube.

2. Bacterivores. Many kinds of freeliving nematodes feed only on bacteria,which are always extremely abundant in soil. In these nematodes, the "mouth", or stoma, is a hollow tube for ingestion of bacteria. This group includes many members of the order Rhabditida as well as several other orders which are encountered less often. These nematodes are beneficial in the decomposition of organic matter

3. Omnivores. The food habits of most nematodes in soil are relatively specific. For example, bacterivores feed only on bacteria and never on plant roots, and the opposite is true for plant parasites. A few kinds of nematodes may feed on more than one type of food material, and therefore are considered omnivores. For example, some nematodes may ingest fungal spores as well as bacteria. Some members of the order Dorylaimida may feed on fungi, algae, and other animals.

4. Predators. These nematodes feed on other soil nematodes and on other animals of comparable size. They feed indiscriminately on both plant parasitic and free-living nematodes. One order of nematodes, the Mononchida, is exclusively predacious, although a few predators are also found in the Dorylaimida and some other orders. Compared to the other groups of nematodes, predators are not common, but some of them can be found in most soils.

5. Fungivores. This group of nematodes feeds on fungi and uses a stylet to puncture fungal hyphae. Many members of the order Aphelenchida are in this group. Like the bacterivores, fungivores are very important in decomposition.

Community Composition

6. Unknown. Since free-living nematodes have not been studied very much, the food habits of some of them are unknown. The microscopic size of these animals presents additional difficulties. For example, it can be very difficult to distinguish whether a nematode is feeding on dead cells from a plant root or on fungi growing on the cell surface. Sometimes a nematode showing this feeding behavior may be classified simply as a root or plant associate.

Anatomy Basically a Nematode is a long hollow tube within which is another tube, the alimentary canal and the reproductive organs. Nematodes are round in cross section, this is because unlike the other worms that below them in the phyla table they maintain their body fluids under great pressure. To contain this high pressure nematodes have an extremely tough, yet elastic and flexible cuticle. This cuticle consists of up to 9 layers of proteinaceous fibres, with 3 layers being easily discerned, these are called, from the outside in, the cortex, the matrix layer and the fibre layer. Despite its complexity the Nematode cuticle is permeable to both water and gases, so respiration occurs through it. Beneath the cuticle is a hypodermis and a layer of longitudinal muscle. The combination of the flexure of these muscles with the high pressure of the system produces a characteristic whip-like wriggle that Nematodes use to swim. Scientifically this is called undulatory propulsion with sinusoidal waves passing back along the body. At the anterior (head) end there is a mouth which has 3 lips behind which predatory species possess a few teeth, this leads to a pharynx which is triangular in cross section. Because of the high pressure within the body unsupported organs such as the intestines tend to collapse in much the same way that an uninflated bicycle tube tends to become oval or flat in cross section when laid flat on the table. The pharynx of Nematodes is an efficient pump and forces food into the intestines, there is a one way valve between the intestines and the pharynx. The pharynx can, when this valve is closed, be used to suck liquid food into the mouth. Digestion is rapid and faeces are expelled under pressure. This pressure is so great that the parasitic nematode Ascaris lumbricoides which is about 12cm to 18cm long (5 to 7 inches) may shoot its faeces 60cm or 2 feet into the air. Nematodes, especially free living forms generally have a reasonably well developed nervous system. This is comprised of a circum-pharyngeal nerve ring made up from 4 nerve ganglia from which 6 longitudinal nerves extend down through the body to the various parts of the gut and the reproductive organs. There are also 6 shorter nerves which extend forwards from the circum-pharyngeal ganglia towards the mouth. Nematodes have no circulatory or respiratory organs and the excretion of metabolic waste is via two simple ducts or tubules which have no nephridia or flame cells.

Nematodes are copiously reproductive and most of their body cavity, which is a pseudocoelom is filled with paired sets of reproductive organs, either ovaries or testes. Males and females copulate and the male introduces sperm to the females vagina with the help of 2 stiff horny spicules that are a part of his cloaca. Fertilisation is internal and females lay eggs over a prolonged time period, thus a female Ascaris lumbricoides may lay her eggs at the rate of 200,000 per day and have had a total 27 million eggs within her at the start of her reproductive career. Young nematodes hatch from these eggs and go through 4 moults before they become adults

Morphology Roundworms are unsegmented, bilaterally symmetric and triploblastic protostomes with a complete digestive system. They have no circulatory or respiratory systems so they use diffusion to breathe. Although they have no circulatory system, nutrients are transported throughout the body via fluid in the pseudocoelom. They are thin and are round in cross section. Nematodes are one of the simplest animal groups to have a complete digestive system, with separate orifices for food intake and waste excretion, a pattern followed by all subsequent, more complex animals. The body cavity is a pseudocoelom (persistent blastula), which lacks the muscles of coelomate animals that protects the body from drying out, from digestive juices, or from other harsh environments. Although this cuticle allows movement and shape changes via a hydrostatic skeletal system, it is very inelastic so does not allow the volume of the worm to increase. Therefore, as the worm grows, it has to molt and form new cuticles. The cuticles don't allow volume to increase so as to keep hydrostatic pressure inside the organism very high. For this reason, the roundworms do not possess circular muscles (just longitudinal ones) as they're not required. This hydrostatic pressure is the reason the roundworms are round. Nematodes have a simple nervous system, with a main ventral nerve cord (pic.1a) and a smaller dorsal nerve cord(pic.1b) . Sensory structures at the anterior end are cord called amphids, while sensory structures at the posterior end are called phasmids. There are no circular muscles, so the body can only undulate from side to side. Contact with solid objects is necessary for locomotion; its thrashing motions vary from mostly to completely ineffective at swimming.

Pic. 1a

Pic. 1b

Morphology

Reproduction Reproduction is usually sexual. Males are usually smaller than females (often much smaller) and often have a characteristically bent tail for holding the female for copulation. During copulation, one or more chitinized spicules move out of the cloaca and are inserted into genital pore of the female. Amoeboid sperm crawl along the spicule into the female worm. Nematode sperm is thought to be the only eukaryotic cell without the globular protein G-actin. Eggs may be embryonated or unembryonated when passed by the female, meaning that their fertilized eggs may not yet be developed. In free-living roundworms, the eggs hatch into larva, which eventually grow into adults; in parasitic roundworms, the life cycle is often much more complicated. Nematodes as a whole possess a wide range of modes of reproduction. Some nematodes, specifically Heterorhabditis spp., undergo a process called : birth causing maternal death. Some nematodes, like other animals (for example segmented worms), are hermaphroditic. The hermaphroditic nematode keeps its selffertilized eggs inside its uterus until they hatch. The juvenile nematodes will then ingest the parent nematode. This process is significantly promoted in environments with a low or reducing food supply. The nematode model species Caenorhabditis elegans and C. briggsae exhibit androdioecy, which is very rare amongst animals. The single genus Meloidogyne (root-knot nematodes) exhibit a range of reproductive modes including sexuality (amphimixis), meiotic parthenogenesis () and mitotic parthenogenesis (apomixis).

Several Member Nemathode - Ascaris lumbricoides (rounds worm)

males are smaller and have hooks

Ascariasis Ascariasis is a human disease caused by the parasitic roundworm Ascaris lumbricoides. Perhaps as many as one quarter of the world's people are infected, and ascariasis is particularly prevalent in tropical regions and in areas of poor hygiene. Other species of the genus Ascaris are parasitic and can cause disease in domestic animals. Infection occurs through ingestion of food contaminated with feces containing Ascaris eggs. The larvae hatch, burrow through the intestine, reach the lungs, and finally migrate up the respiratory tract. From there they are then reswallowed and mature in the intestine, growing up to 30 cm (12 in.) in length and anchoring themselves to the intestinal wall. Infections are usually asymptomatic, especially if the number of worms is small. They may however be accompanied by inflammation, fever, and diarrhea, and serious problems may develop if the worms migrate to other parts of the body.

Life cycle First appearance of eggs in stools is 60-70 days. In larval ascariasis, symptoms occur 4-16 days after infection. The final symptoms are gastrointestinal discomfort, colic and vomiting, fever, and observation of live worms in stools. Some patients may have pulmonary symptoms or neurological disorders during migration of the larvae. However there are generally few or no symptoms. A bolus of worms may obstruct the intestine; migrating larvae may cause pneumonitis and eosinophilia.

Life cycle ascaris lumbricodes Adult worms (1) live in the lumen of the small intestine. A female may produce approximately 200,000 eggs per day, which are passed with the feces (2). Unfertilized eggs may be ingested but are not infective. Fertile eggs embryonate and become infective after 18 days to several weeks (3), depending on the environmental conditions (optimum: moist, warm, shaded soil). After infective eggs are swallowed (4), the larvae hatch (5), invade the intestinal mucosa, and are carried via the portal, then systemic circulation and/or lymphatics to the lungs . The larvae mature further in the lungs (6) (10 to 14 days), penetrate the alveolar walls, ascend the bronchial tree to the throat, and are swallowed (7). Upon reaching the small intestine, they develop into adult worms (8). Between 2 and 3 months are required from ingestion of the infective eggs to oviposition by the adult female. Adult worms can live 1 to 2 years.

Source The source of transmission is from soil and vegetation on which fecal matter containing eggs has been deposited. Ingestion of infective eggs from soil contaminated with human feces or transmission and contaminated vegetables and water is the primary route of infection. Intimate contact with pets which have been in contact with contaminated soil may result in infection, while pets which are infested themselves by a different type of roundworm can cause infection with that type of worm (Toxocara canis, etc) as occasionally occurs with groomers. Transmission from human to human by direct contact is impossible.

Symptoms Patients can remain asymptomatic for very long periods of time. As larval stages travel through the body, they may cause visceral damage, peritonitis and inflammation, enlargement of the liver or spleen, toxicity, and pneumonia. A heavy worm infestation may cause nutritional deficiency; other complications, sometimes fatal, include obstruction of the bowel by a bolus of worms (observed particularly in children) and obstruction of the bile or pancreatic duct. More than 796 Ascaris lumbricoides worms weighing 550 g [19 ounces] were recovered at autopsy from a 2-year-old South African girl. The worms had caused torsion and gangrene of the ileum, which was interpreted as the cause of death. Ascaris takes most of its nutrients from the partially digested host food in the intestine. There is limited evidence that it can also pierce the intestinal mucous membrane and feed on blood, but this is not its usual source of nutrition. As a result, Ascaris infection does not produce the anemia associated with some other roundworm infections.

Prevention Prevention includes: use of toilet facilities; safe excreta disposal; protection of food from dirt and soil; thorough washing of produce; and hand washing. Food dropped on the floor should never be eaten without washing or cooking, particularly in endemic areas. Fruits and vegetables should always be washed thoroughly before consumption.

Treatment Pharmaceutical drugs that are used to kill roundworms are called ascaricides and include:  Mebendazole (Vermox) (C16H13N3O2). Causes slow immobilization and death of the worms by selectively and irreversibly blocking uptake of glucose and other nutrients in susceptible adult intestine where helminths dwell. Oral dosage is 100 mg 12 hourly for 3 days.  Piperazine (C4H10N2.C6H10O4). A flaccid paralyzing agent that causes a blocking response of ascaris muscle to acetylcholine. The narcotizing effect immobilizes the worm, which prevents migration when treatment is accomplished with weak drugs such as thiabendazole. If used by itself it causes the worm to be passed out in the feces. Dosage is 75 mg/kg (max 3.5 g) as a single oral dose.  Pyrantel pamoate (Antiminth, Pin-Rid, Pin-X) (C11H14N2S.C23H16O6) Depolarizes ganglionic block of nicotinic neuromuscular transmission, resulting in spastic paralysis of the worm. Spastic (tetanic) paralyzing agents, in particular pyrantel pamoate, may induce complete intestinal obstruction in a heavy worm load. Dosage is 11 mg/kg not to exceed 1 g as a single dose.  Albendazole (C12H15N3O2S) A broad-spectrum antihelminthic agent that decreases ATP production in the worm, causing energy depletion, immobilization, and finally death. Dosage is 400 mg given as single oral dose (contraindicated during pregnancy and children under 2 years).  Thiabendazole. This may cause migration of the worm into the esophagus, so it is usually combined with piperazine.  Hexylresorcinol effective in single doseSantonin, more toxic than hexylresorcinol,  Oil of chenopodium, more toxic than hexylresorcinol, dition Also, corticosteroids can treat some of the symptoms, such as inflammation.

- Quick facts Genus and Species

Ascaris lumbricoides

Common Name

Giant Intestinal Roundworm

Etiologic Agent of:

Ascariasis

Infective stage

Embryonated Egg

Definitive Host

Man

Portal of Entry

Mouth

Mode of Transmission

Ingestion of Embryonated egg through contaminated food or water

Habitat

Small Intestine

Pathogenic Stage

Adult, Larva

Mode of Attachment

Retention in the mucosal folds using pressure

Mode of Nutrition

Feeding of Chyme

Pathogenesis

Larva – pneumonitis, ; Adult – Obstruction, Liver abscess, Appendicitis. With Blood-Lung Phase along with Hookworms and Strongyloides stercoralis.

Laboratory diagnosis

Concentration methods and Direct Fecal Smear

Treatment

Albendazole, Mebendazole, or Pyrantel pamoate

Diagnostic Feature - Adult

Female - prominent genital girdle

Diagnostic Feature - Egg

Coarse mammilated albuminous coating

2.

Wuchereria bancrofti (filaria) Wuchereria bancrofti or Filaria, is a parasitic filarial nematode worm spread by a mosquito vector. It is one of the three parasites that cause lymphatic filariasis. Elephantiasis can result if the infection is left untreated. Limited treatment modalities exist and no vaccines have been developed. W. bancrofti carry out their life cycle in two host. Human beings serve as the definitive host and mosquitoes as their intermediate hosts. The adult parasites reside in the lymphatics. They are viviparous. The first stage larvae are known as microfilariae. The microfilaria are present in the circulation. The microfilaria migrate between the deep and the peripheral circulation. During the day they are present in the deep veins and during the night the migrate to the peripheral circulation. Next, the worm is transferred into a vector; the

most common vectors are the mosquito species: Culex, Anopheles, Mansonia, and Aedes. Inside their second host, it matures into motile larvae. When its current host feeds, and it is egested into the blood stream of its new human host. The larvae moves to the lymph nodes, predominantly in the legs and genital area, and develops into adult worm over the course of a year. By this time, an adult female can produce microfilariae herself.

• Wuchereria bancrofti

- Pathogenesis

The pathogenesis of W. bancrofti infection is dependent on the host's immune system and inflammatory responses. After infection, the worms will mature within 6-8 months and then the release of the microfilariae will begin. These microfilariae worms can be released for up to ten years. 1. Asymptomatic Phase -Usually consists of high microfilaremia infection and individuals show no symptoms of being infected. This occurs due to the cytokine IL4 suppressing the activity of TH1 cells in our immune system. This can occur for years until the inflammatory reaction rise again.

2. Inflammatory (Acute) Phase -The antigens from the female adult worms elicit inflammatory responses. The worms in the lymph channels disrupt the flow of the lymph causing lymphedema. The individual will exhibit fever, chills, skin infections, painful lymph nodes, and tender skin of the lymphedematous extremity. These symptoms often lessen after 5-7 days. Other symptoms that may occur include: orchitis-inflammation of the testes, which is accompanied by painful immediate enlargement and epididymitis-which is the inflammation of the spermatic cord. 3. Obstructive (Chronic) Phase -marked by lymph varices, lymph scrotum, hydrocele, chyluria(lymph in urine), and elephantiasis. Microfilariae are not normally present in this phase. A key feature of this phase is scar formation from affected tissue areas. Other features include thickening of the skin and elephantiasis which develops gradually with the attack of the lymphatic system. Elephantiasis affect men mainly on the legs, arms, and scrotum. In women, the legs and arms are affected.

Life cycle

Treatment/Control The parasite's severe symptoms can be avoided by cleansing the skin, surgery, or the use of therapeutic drugs, such as Diethylcarbamazine(DEC), ivermectin, or albendazole. The drug of choice however, is DEC, which can eliminate the microfilariae from the blood and also kill the adult worms with a dosage of 6 mg/kg semiannually or annually. A treatment that includes ivermectin with DEC or albendazole is more effective than each drug alone. Protection is similar to that of other mosquito spread illnesses; one can use barriers both physical (a mosquito net), chemical (insect repellent), or mass chemotherapy′ as a method to control the spreading of the disease.

3.

Necator / Ancylostoma duodenale (hookworm) China, and Indonesia, while A. duodenale predominates in the Middle East, North Africa, India and (formerly) in southern Europe. The Ancylostoma braziliense and A. tubaeforme species infect cats, while A. caninum infects dogs. Uncinaria stenocephala infects both dogs and cats.Hookworms are much smaller than the large roundworm, Ascaris lumbricoides, lumbricoides, and the complications of tissue migration and mechanical obstruction so frequently observed with roundworm infestation are less frequent in hookworm infestation. The most significant risk of hookworm infection is anemia, secondary to loss of iron (and protein) in the gut. The worms suck blood voraciously and damage the mucosa. However, the blood loss in the stools is occult blood loss (not visibly apparent).

Hookworm is a parasitic nematode worm that lives in the small intestine of its host, which may be a mammal such as a dog, cat, or human. Two species of hookworms commonly infect humans, Ancylostoma duodenale and Necator americanus. Hookworms are also bilateral, meaning that if cut in half, the worm would be the exact same on each side. Necator americanus predominates in the Americas, Sub-Saharan Africa, Southeast Asia,

Life cycle

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Infection of the host is by the larvae, not the eggs. While A. duodenale can be ingested, the usual method of infection is through the skin; this is commonly caused by walking barefoot through areas contaminated with fecal matter. The larvae are able to penetrate the skin of the foot, and once inside the body, they migrate through the vascular system to the lungs, and from there up the trachea, and are swallowed. They then pass down the esophagus and enter the digestive system, finishing their journey in the intestine, where the larvae mature into adult worms. Once in the host gut, Necator tends to cause a prolonged infection, generally 1–5 years (many die within a year or two of infecting), though some adult worms have been recorded to live for 15 years or more. On the other hand, Ancylostoma adults are short lived, surviving on average for only about 6 months. However, infection can be prolonged because dormant larvae can be "recruited" sequentially from tissue "stores" over many years, to replace expired adult worms. This can give rise to seasonal fluctuations in infection prevalence and intensity (apart from normal seasonal variations in transmission). . They mate inside the host, females laying up to 30,000 eggs per day and some 18 to 54 million eggs during their lifetime, which pass out in feces. Because it takes 5–7 weeks for adult worms to mature, mate and produce eggs, in the early stages of very heavy infection, acute symptoms might occur without any eggs being detected in the patient's feces.

Symptoms There are no specific symptoms or signs of hookworm infection. As mentioned above, they arise from a combination of intestinal inflammation and progressive iron/proteindeficiency anemia. Larval invasion of the skin might give rise to intense, local itching, usually on the foot or lower leg, which can be followed by lesions that look like insect bites, can blister, and last for a week or more. Animal hookworm larvae on penetrating humans may produce a creeping eruption called cutaneous larva migrans. The larvae migrate in tortuous tunnels in between stratum germinativum and stratum corneum of the skin, causing serpigenous vesicular lesions. With advancing movement of the larvae, the rear portions of the lesions become dry and crusty. The lesions are typically intensely pruritic. Coughing, chest pain, wheezing, and fever will sometimes be experienced by people who have been exposed to very large numbers of larvae. Epigastric pains, indigestion, nausea vomiting, constipation, and diarrhea can occur early or in later stages as well, although gastrointestional symptoms tend to improve with time. Signs of advanced severe infection are those of anemia and protein deficiency, including emaciation, cardiac failure and abdominal distension with ascites.

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Prevention The infective larvae develop and survive in an environment of damp dirt, particularly sandy and loamy soil. They cannot survive in clay or muck. The main lines of precaution are those dictated by sanitary science: Do not defecate outside latrines, toilets etc. Do not use human excrement or raw sewage as manure/fertilizer in agriculture Deworm pet dogs — canine and feline hookworms rarely develop to adulthood in humans (Ancylostoma caninum, the common dog hookworm, occasionally develops into an adult to cause eosinophilic enteritis in people), but their invasive larvae can cause an itchy rash called cutaneous larva migrans Treatment The hookworm can be treated with local cryotherapy when it is still in the skin. Albendazole is effective both in the intestinal stage and during the stage the parasite is still migrating under the skin. In case of anemia, iron supplementation can cause relief symptoms of iron deficiency anemia. However, as red blood cell levels are restored, shortage of other essentials such as folic acid or vitamin B12 may develop, so this might also be supplemented. The most common treatment for Hookworm are Benzimidazoles (BZAs),

Genus and Species

Necator americanus

Ancylostoma duodenale

Common Name

New world hookworm, American murderer

Old world hookworm

Etiologic Agent of:

Necatoriasis, Uncinariasis

Ancylostomiasis, Wakana disease

Infective stage

Filariform larva

Filariform larva

Definitive Host

Man

Man

Portal of Entry

Usually via skin penetration rather than ingestion

Usually via ingestion rather than skin penetration

Mode of Transmission

Skin > Mouth

Mouth > Skin

Small Intestine

Small Intestine

Larva

Larva

Habitat Pathogenic Stage Maturation time in host (days)

49-56

53

Mode of Attachment

Oral attachment to mucosa by sucking

Same

Mode of Nutrition

Sucking and Ingesting of blood Same

Same

Treatment

Albendazole, Mebendazole, or Pyrantel Pamoate

Same

5-9 for males; 9-11 for females

8-11 for males; 10-13 for females

Length of adult hookworm (mm) Shape

Egg output per female worm per day

Head curved opposite to curvature of body, Head continuous in same giving a hooked appearance to anterior direction as the body end 5,000-10,000

10,000-25,000

4.

Enterobius vermicularis (pinworm)

The pinworm (Genus Enterobius), also known as threadworm or seat worm, is a common human intestinal parasite, especially in children. The medical condition associated with pinworm infestation is known as enterobiasis , or sometimes oxyuriasis.

Reproduction After mating, the male dies. The female migrates to the anus and emerges, usually during the night, to deposit about 10,000 to 20,000 eggs in the perianal area (around the anus). She then secretes a substance which causes a very strong itching sensation, inciting the host to scratch the area and thus transfer some of the eggs to the fingers. Eggs can also be transferred to cloth, toys, and the bathtub. Once ingested orally, the larvae hatch in the small intestine, specifically the duodenum, and migrate back to the large intestine where they mature. Maturity is reached in 30–45 days. The eggs can survive for 2 to 3 weeks on their own outside of the human body. In some cases, the larvae will hatch in the peri-anal area and travel back inside the anus, up the rectum, and back into the intestines where they mature

Effects Except for itching pinworm infestation does not usually cause any damage to the body. Sleep disturbance may arise from the itching or crawling sensations. Some case reports suggest that severe infestation may be associated with an increased risk for appendicitis. There is also some evidence of an association between enterobiasis and diminished zinc levels.

Treatment Anti-pinworm drugs such as albendazole (Albenza), mebendazole (Vermox, OVEX), Piperazine and pyrantel pamoate (Pin-X, Reese's Pinworm Medication) are commonly used to treat pinworms as well as ascaris lumbricoides (the roundworm). It is not a necessity to visit a doctor to get these drugs, as pyrantel pamoate (Pin-X) is available as an over-thecounter medication (albendazole and mebendazole are prescription in the US); ask a pharmacist for medicines to treat pinworms (or threadworms as they are known in the UK). These medicines kill the pinworms 95% of the time, but do not kill the eggs. The person being treated may have to return after a time of two weeks to be retreated. Another precaution is to wash the hands before eating (to prevent any pinworm eggs under fingernails from being ingested) and to wash any area or clothes which have touched or been in the vicinity of the infected areas

5. Trichinella spiralis

The species Trichinella spiralis is an nematode parasite, occurring in rats, pigs, and humans, and is responsible for the disease trichinosis. It is sometimes referred to as the "pork worm" due to it being found commonly in pork or rat products that are undercooked

Symptoms The first symptoms may appear between 12 hours and two days after ingestion of infected meat. The migration of worms in the intestinal epithelium can cause traumatic damage to the host tissue and the waste products they excrete can provoke an immunological reaction. The resulting inflammation can cause symptoms such as nausea, vomiting, sweating and diarrhea. Five to seven days after the appearance of symptoms facial edema and fever may occur. After 10 days intense muscular pain, difficulty breathing, weakening of pulse and blood pressure, heart damage and various nervous disorders may occur, eventually leading to death due to heart failure, respiratory complications or kidney malfunction

Life cycle Larvae encysted in the muscles remain viable for some time. When the muscle tissue is eaten by a human, the cysts are digested in the stomach; the released larvae migrate to the intestine to begin a new life cycle. Female trichina worms live about six weeks and in that time may release larvae. The migration and encystment of larvae can cause fever, pain, and even death because of their potential to eat living tissue. One of the classic signs of Trichinella spiralis infection is a combination of splinter hemorrhages (not to be confused with those of bacterial endocarditis) and periorbital edema (eye swelling). Trichina are classified in the phylum Nematoda, which includes Caenorhabditis elegans, an important scientific model organism for studying genetics behind various topics such as development, neuroscience, disease, and aging.

Diagnosis and treatment Muscle biopsy is used for trichinosis detection. Several immunodiagnostic tests are also available. There are currently no satisfactory treatments for trichinosis, however symptoms can be relieved by use of analgesics and corticosteroids

Benefit and loss Benefit -

Loss -

conclusion