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Post by killerzzz on Jun 26, 2007 4:59:37 GMT
Thats right folks: parasites. Those annoying and sometimes terrible little buggers, that cause so much trouble. Here is where you get to tell us about ones you're interested in. I'll start with a particularily nasty one. >: ) Warning. This is a wee bit... unpleasant (gross? sure). I'll let Wikipedia give us a nice intro. The candirú or canero (Vandellia cirrhosa) or toothpick fish is a freshwater fish in the group commonly called the catfish. It is found in the Amazon River and has a reputation among the natives as the most feared fish in its waters, even over the piranha. The species has been known to grow to a size of 6 inches in length and is eel shaped and translucent, making it almost impossible to see in the water. The candirú is a parasite.So why is this little guy so horrible? Well, lets start from the top. The candirú usually preys on fish: it will swim into their gills, then attaches itself on the inside with barbs or "spines" (picky spikes : / ). Once lodged inside, it will suck the victim's blood, like a tick or leech. Why should you worry? You're not a fish, right? Well, you have holes on your body too. In other words don't go swimming in the Amazon. See, these little evil fishies have the tendancy to go swimming up your bum or pee-hole and making the inside its home. Just FYI, that hurts alot. They're impossible to pull out; surgery will be necessary. Urinating in the Amazon waters brings up your chances to pick up this new friend, since they're attracted to the smell of pee. A traditional cure involves the use of two plants, the Xagua plant (Genipa americana) and the Buitach apple which are inserted (or their extract in the case of tight spaces) into the affected area. These two plants together will kill and then dissolve the fish. More often, infection causes shock and death in the victim before the candirú can be removed. I've also heard that if you urinate into the Amazon river, the candirú will manage to swim up your pee-stream and make his way like that. This is untrue. Its just not possible, for a bunch of reasons. Read up on it if you want to know more. Also, don't go swimming in the Orinoco river either. Same game. Killerzzz
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Post by LaFille on Jun 26, 2007 5:18:51 GMT
Lol, great topic Killerzzz, and erm... enthusiastic first pick? Good idea about the warning too. I'm off for the night, but will try to come up with some too eventually. Oh, and it's a good time to talk about parasites, as it seems the fiesta time for a common kind that spoil our nights out these days...
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Post by Galadriel on Jun 26, 2007 13:14:47 GMT
Another interesting parasite is the parasitic roundworm Ascaris lumbricoides. Warning, don't read it if you're a bit sensitive ;D 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 fecal matter 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.
Roughly 1.5 billion individuals are infected with this worm, primarily in Africa and Asia. Ascariasis is endemic in the United States including Gulf Coast; in Nigeria and in Southeast Asia. One study indicated that the prevalence of ascariasis in the United States at about 4 million (2%)[citation needed]. In a survey of a rural Nova Scotia community, 28.1% of 431 individuals tested were positive for Ascaris, all of them being under age 20, while all 276 tested in metropolitan Halifax were negative.
Deposition of ova (eggs) in sewage hints at the degree of ascariasis incidence. A 1978 study showed about 75% of all sewage sludge samples sampled in United States urban catchments contained Ascaris ova, with rates as high as 5 to 100 eggs per litre[citation needed]. In Frankfort, Indiana, 87.5% of the sludge samples were positive with Ascaris, Toxocara, Trichuris, and hookworm[citation needed]. In Macon, Georgia, one of the 13 soil samples tested positive for Ascaris[citation needed]. Municipal wastewater in Riyadh, Saudi Arabia detected over 100 eggs per litre of wastewater and in Czechoslovakia was as high as 240-1050 eggs per litre.
Ascariasis sources can often be measured by examining food for ova. In one field study in Marrakech, Morocco, where raw sewage is used to fertilize crop fields, Ascaris eggs were detected at the rate of 0.18 eggs/kg in potatoes, 0.27 eggs/kg in turnip, 4.63 eggs/kg in mint, 0.7 eggs/kg in carrots, and 1.64 eggs/kg in radish[6]. A similar study in the same area showed that 73% of children working on these farms were infected with helminths, particularly Ascaris, probably as a result of exposure to the raw sewage.
That is one nasty little bugger if you're infected When I was still in school, I learned about this one and my teacher told me some stories. Once there was an African woman that was pregnant, but she died before giving birth to her child. When they cut her open to release the baby, there wasn't one at all! Her belly was filled with those worms and they had eaten her from the inside.
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Post by ss on Jun 26, 2007 14:43:36 GMT
Cheeeezzze....What a topic.....but my favorite parasite is the local welfare recipeint... ;D
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Post by Shan on Jun 26, 2007 18:37:09 GMT
how about if you become the local blood bank. ;D
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Post by killerzzz on Jun 26, 2007 23:05:36 GMT
@kylia: Uhmmm, ok that was grosser than mine. ;D I'll go into details on some later, but does anyone remember this sweetie Cleglaw posted at Larian? The article he showed us has expired, but here's Wiki's take on it and its effects. If you're just gunna take a look at one article, make it the effects. They're pretty interesting. Killerzzz
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Post by Galadriel on Jun 29, 2007 8:46:48 GMT
Sleeping sickness or African trypanosomiasis is a parasitic disease in people and animals, caused by protozoa of genus Trypanosoma and transmitted by the tsetse fly.
The disease is endemic in certain regions of Sub-Saharan Africa, covering about 36 countries and 60 million people. It is estimated that 50,000 to 70,000 people are currently infected, the number having declined somewhat in recent years. Three major epidemics have occurred in the past hundred years, one from 1896–1906 and the other two in 1920 and 1970.
Symptoms begin with fever, headaches, and joint pains. As the parasites enter through both the blood and lymph systems, lymph nodes often swell up to tremendous sizes. Winterbottom's sign, the telltale swollen lymph glands along the back of the neck may appear. If untreated, the disease slowly overcomes the defenses of the infected person, and symptoms spread to include anemia, endocrine, cardiac, and kidney diseases and disorders. The disease then enters a neurological phase when the parasite passes through the blood-brain barrier. The symptoms of the second phase give the disease its name; besides confusion and reduced coordination, the sleep cycle is disturbed with bouts of fatigue punctuated with manic periods progressing to daytime slumber and nighttime insomnia. Without treatment, the disease is fatal, with progressive mental deterioration leading to coma and death. Damage caused in the neurological phase can be irreversible.
In addition to the bite of the tsetse fly, the disease is contractible in the following ways:
* Mother to child infection: the trypanosome can cross the placenta and infect the fetus, causing perinatal death. * Laboratories: accidental infections, for example, through the handling of blood of an infected person and organ transplantation, although this is uncommon. * Blood transfusion
The condition has been present in Africa since at least the 14th century, and probably for thousands of years before that. The causative agent and vector were not identified until 1902–1903 by Sir David Bruce, and the differentiation between protozoa was not made until 1910. The first effective treatment, Atoxyl, an arsenic based drug developed by Paul Ehrlich and Kiyoshi Shiga was introduced in 1910 but blindness was a serious side effect. Numerous drugs designed to treat the disease have been introduced since then.
There have been three severe epidemics in Africa over the last century: one between 1896 and 1906, mostly in Uganda and the Congo Basin, one in 1920 in several African countries, and one that began in 1970 and is still in progress. The 1920 epidemic was arrested due to mobile teams systematically screening millions of people at risk. The disease had practically disappeared between 1960 and 1965. After that success, screening and effective surveillance were relaxed due to the withdrawal of colonial authorities, and the disease has reappeared in endemic form in several foci over the last thirty years.
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Post by killerzzz on Jul 1, 2007 5:51:18 GMT
Mmmmm, tapeworms. Well, those roundworms reminded me of another friendly fiend. The Tapeworm. These guys, though not as nasty as some of the others we've mentionned, are still quite a problem, especially before modern medicine. You get them by eating infected meat (usually pork or beef, and sometimes fish) that has the eggs in it. You can often tell if there are eggs by little zit-looking marks on the meat (a whitish bumb, with redness around it). The eggs hatch in in your intestines and thats where they latch on. There they will steal mostly all the nutrients of what you eat, and fatten up. Well, this causes two problems. 1. They can get really fat, and completely block your intestines; yay. 2. They're basically starving you to death. This doesn't help either: Tapeworms can grow 15 to 30 feet (10 metres) in length. The largest tapeworms grow up to 59 feet (18 metres). -- Wikipedia Then, they lay more eggs, which come out in your poop, so they can infect whatever decides to eat it. Or, better yet, the eggs move from your stool in the sewers and infect animals that live and eat there. Apparently, there's a really jerk version of the tapeworm: Cysticercosis, a dangerous complication of the parasite Taenia solium, may occur when the larvae develop outside the intestinal tract. This parasite can move from the intestines to muscle tissue, bone marrow, fingers, and in some cases the central nervous system (neurocysticercosis). The latter infection can lead to seizures and other neurological problems. -- Wikipedia Well, more of a jerk. Here, medicine is the best treatment. There's this medicine that you eat, that kills the worm in your intestines, then he comes out in your bowl-movements. Ooo, here it is: CDC guidelines for treatment is a prescription drug called praziquantel (Biltricide). Praziquantel is generally well tolerated. Sometimes more than one treatment is necessary.Apparently, there are other 'methods' for getting rid of them, but scientists say its a myth. I'll put it in the old fashionned remedies section. ;D Killerzzz
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Post by LaFille on Jul 2, 2007 5:50:13 GMT
The parasit from the Sleep sickness looks a lot like that of the one that is in the case of malaria (paludism) in his ways and transmition mode. The tapeworm (and quite any other parasit infection, in fact), I prefer the moderm medical means to get rid of it, thanks. ;D What you see there on the pic is the lovely "head" by which the friend here grips at his beloved home; and it releases bits of his tip a bit like egg pockets at the other end, if I recall correctly and am not mixing it up with another friendly creature of the kind.
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Post by Galadriel on Jul 3, 2007 20:51:28 GMT
Now I wanna make a post about Pete's favorite parasites: The lice ;D
The head louse (Pediculus humanus capitis) is one of the many varieties of sucking lice specialized to live on different areas of various animals.
As the name implies, head lice are specialized to live among the hair present on the human head and are exquisitely adapted to living mainly on the scalp and neck hairs of their human host. Lice present on other body parts covered by hair are not head lice but are either pubic lice (Pthirus pubis) or body lice (Pediculus humanus humanus).
Description
The adult head louse resembles a miniature ant that appears flat when viewed from the side through a strong magnifying glass. Head lice have a head, thorax and abdomen with six legs,(which makes them insects) but their two front legs are very large in order to grab onto the hair shafts. Head lice are tan to greyish-white in color. Headlice are easy to notice in blonde or ginger hair,because yellow and orange are light colours.Human lice do not feed on the blood of other animals, only humans.
Life cycle
Louse eggs on the hair very close to the scalp are the primary sign of an active infestation. A female can lay up to 50-150 eggs in its life, but it can lay up to 100 eggs in 30 days. She also glues her eggs, sometimes called "nits", which look like tiny white beads, to hair shafts very close to the scalp (usually about a centimeter or two [half an inch to three-quarters of an inch] from the scalp). Eggs are very small, about the size of a period "." (full stop) in normal printing. Eggs may appear white, yellowish, brownish or greyish, but are almost always lighter colored. An egg normally undergoes a 7-9 day incubation before hatching as a baby nymph.
Classically, a louse egg does not become a "nit" until after it has completed its incubation stage, thus leaving a "nit." A "nit" is either the empty shell remaining after the nymph has departed or the dead egg that remains if incubation was not successful. Dead eggs will appear darker, or raisin-like, as they dry out. "Nits" of this sort are usually found over one centimeter (approximately one-half inch) or more away from the scalp and are not considered a sign of active infestation. Some people refer to lice eggs, live or dead, as "nits." In common usage, an egg that is still incubating may also be called a "nit."
Head lice have no wings and move primarily by crawling. They have no adaptations for jumping.
Whether a louse is male or female is not apparent until it is nearly mature. It takes about 10 days for a head louse to grow into an adult. Fertilization of eggs takes place once the female is mature. The female can then lay 3-7 eggs each day for the next 28 to 30 days, her normal life span. Females may lay multiple eggs on one hair or lay an egg on a hair and then move on.
There are three main stages in the life of a head louse: the nit, the nymph, and the adult.
* Nit:Nits are head lice eggs. They are hard to see and are found firmly attached to the hair shaft. They are oval and usually yellow to white. Nits take about 1 week to hatch.
* Nymph: The nit hatches into a baby louse called a nymph. It looks like an adult head louse, but is smaller. Nymphs mature into adults about 7 days after hatching. To live, the nymph must feed on blood. It metamorphoses 3 times before it reaches the adult stage. Most head lice at this stage are almost transparent until they have eaten (sucked blood from a human skin). Then they can be seen more easily since it will be possible to see the tiny amount of red or brown blood in their stomach. To the unaided eye, it will appear like a small red dot usually about 0.5 mm or less in diameter. With a magnifying glass or microscope it is possible to see the head and legs, and since a louse is quite transparent at this stage, the digestive system, showing the blood that was ingested. * Adult: To live, adult lice need to feed on blood. Females are usually larger than males, and can lay several nits in a day. If the louse falls off a person, it usually dies within 1-2 days, although experiments have shown them to live longer. A female may continue to lay eggs on other materials similar to the texture of human hair such as stuffed animals with long strands of hair.
Symptoms
The most common symptom is itching of the scalp, caused when the louse bites through the skin to feed on blood. Another thing to be concerned about is hair loss. The lice themselves are essentially harmless, although excessive scratching may cause bleeding of the scalp, which may increase the risk of microbial infection. They suck one's blood and leave droppings in one's hair as well as eggs. Serious diseases such as HIV or Hepititis cannot be spread through lice.
Enjoy and don't go scratching your head now ;D
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Post by Galadriel on Jul 3, 2007 20:57:28 GMT
Wanna know more about the nephew of the head lice? ;D
Crab louse Crab lice, also called pubic lice, (singular, louse) commonly called "crabs" due to their resemblance to a crab, are one of three kinds of human lice in the large group of lice families, the others being head lice and body lice, which live in clothing. Its scientific name is Phthirus or Phthirius pubis, literally 'pubic louse' (from Greek φθειρ : louse).
They are wingless, about 1 to 3 mm long. They attach themselves to hair strands, and hatch out of lidded pods called "nits". Ones that are too tightly attached to be brushed off must be removed by pulling with the nails or a fine-tooth comb.
The crab louse can live in almost any form of human hair, but is found most commonly in pubic hair, leading to its other common name of pubic louse. Its legs are adapted to climbing along relatively widely spaced hairs, and so it can be found in eyebrows, pubic hair, beards, moustaches, underarm hair and even on eyelashes. The individual louse can survive for about 24 hours apart from its necessary human host, so that crab lice can be passed on in sleeping bags and bedding. The louse feeds on blood and can leave irritating spots on the skin, sometimes mistaken for pimples, a condition called Pediculosis pubis.
There are three stages in the life of a pubic louse: the nit, the nymph, and the adult.
* Nit: Nits are pubic lice eggs. They are hard to see and are found firmly attached to the hair shaft. They are oval and usually yellow to white. Nits take about 1 week to hatch. * Nymph: The nit hatches into a baby louse called a nymph. It looks like an adult pubic louse, but is smaller. Nymphs mature into adults about 1 week after hatching. To live, the nymph must feed on blood. * Adult: The adult pubic louse resembles a miniature crab when viewed through a strong magnifying glass. Pubic lice have six legs, but their two back legs are very large and look like the pincher claws of a crab; this is how they got the nickname "crabs." Pubic lice are tan to greyish-white in colour. Females lay nits; they are usually larger than males. To live, adult lice need to feed on blood. If the louse falls off a person, it dies within 1-2 days.
Enjoy once again and don't scratch ;D
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Post by killerzzz on Jul 3, 2007 23:58:18 GMT
Alright guys, here's a challenge for ya. Many believe everything is created for a reason. Maybe it has some religious cause for being, maybe it has a scientific/natural cause for being; either way, for some sort of balance. Why parasites? What reason is there for some creature that simply feeds off the unfortunate living, draining them, and spreading disease? Good question, Killerzzz! ;D I have alot of ideas and answers. But I want to hear yours first: give me your philosophy on parasites. Killerzzz P.S.: Don't stop telling us about other fun parasites just because of this. I'm just opening up a new idea.
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Post by LaFille on Jul 4, 2007 2:47:47 GMT
To answer to your question, just see it a bit that way; parasitism is a form of predation, but without the predator to kill the prey it feeds on. Also, infectious diseases are caused by agents that are like parasits themselves, be it viruses, bacteria, etc. And further than that, in ecology, predation is a word that defines the action of a living organism feeding on another living one in general; that way, it includes herbivores feeding on vegetals and parasitism as well. So in taking it that way, feeding on plants, mushrooms, etc. can be parasitism as well.
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Post by LaFille on Jul 4, 2007 3:03:12 GMT
Now here is an intersting case that at first was thought to be parasitism but that in the end is not; and very particular. ;D AnglerfishesAnglerfish are bony fish in the order Lophiiformes[1], named for their characteristic mode of predation, wherein a fleshy growth from the fish's head (the esca) acts as a lure; this is considered analogous to angling.
Anglerfish are both pelagic and benthic fishes of the abyss (e.g. Ceratiidae) and the continental shelf (e.g. the frogfishes Antennariidae and the monkfish/goosefish Lophiidae) respectively. Pelagic forms are most laterally compressed whereas the benthic forms are often extremely dorse-ventrally compressed (depressed) often with large upward pointing mouths. [...]
Aspects of Reproduction
Anglerfishes of the suborder Ceratioidea employ an unusual mating method. Since individuals are presumably locally rare and encounters doubly so, finding a mate is problematic. When scientists first started capturing ceratioid anglerfish, they noticed that all of the specimens were females. These individuals were a few inches in size and almost all of them had what appeared to be parasites attached to them. It turned out that these "parasites" were the remains of male ceratioids.
At birth, male ceratioids are already equipped with extremely well developed olfactory organs that detect scents in the water. They have no digestive system, and thus are unable to feed independently. They must find a female anglerfish, and quickly, or else they will die. The sensitive olfactory organs help the male to detect the pheromones that signal the proximity of a female anglerfish. When he finds a female, he bites into her flank, and releases an enzyme which digests the skin of his mouth and her body, fusing the pair down to the blood vessel level. The male then atrophies into nothing more than a pair of gonads that release sperm in response to hormones in the female's bloodstream indicating egg release. This is an extreme example of sexual dimorphism. However, it ensures that when the female is ready to spawn, she has a mate immediately available.From Wikipedia.
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Post by janggut on Jul 9, 2007 1:22:38 GMT
i'd like to introduce to u one of the nasty mozzies that kill quite a number of Malaysians every year. not a lot, of course, but every death is a huge loss. Aedes is one of most dangerous mosquitoes especially in the tropics. sadly some of this particular species have been introduced to the US & have spread as far as Iowa. so what is so dangerous about this little mozzie apart from Malaria? Dengue hemorrhagic fever. if u're not so sure that it's any more dangerous than Malaria, well, let me tell u the other names of this disease; break-bone fever or bonecrusher disease. lethality? if detected late - very high.
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Post by LaFille on Jul 9, 2007 3:50:26 GMT
Eeek, that's bad. You take care of yourself with these, rub lemon, vinegar, DEET, smoke, mint, all the kit to keep these little nasties off of you. ;D Mosquitoes are vectors of several diseases; here what to watch more for these times about mosquito-transmitted diseases is the West-Nile virus, but then again the cases are very rare. Bits about mosquitoes: Mosquito is a member of the family Culicidae. These insects have a pair of scaled wings, a pair of halteres, a slender body, and long legs. The females of most mosquito species suck blood (hematophagy) from other animals. This blood sucking characteristic has made mosquitoes one of the most deadly vectors known to man, literally killing millions of people over thousands of years and continuing to kill millions per year.[Size varies but is rarely greater than 16 mm (0.6 inch). Mosquitoes weigh only about 2 to 2.5 mg (0.03 to 0.04 grain). A mosquito can travel up to 10km in a night, and fly for 1 to 4 hours continuously at up to 1-2 km/hr. Most species are nocturnal or dawn or evening feeders (crepuscular). During the heat of the day most mosquitoes land in a cool place and wait for the evenings. They may still bite if disturbed.
Evolution
Mosquitoes are believed to have evolved around 170 million years ago during the Jurassic era (206–135 million years ago) with the earliest known fossils from the Cretaceous era (144–65 million years ago). They are thought to have evolved in South America, spreading initially to the northern continent Laurasia and re-entering the tropics from the north. Some ancestral mosquitoes were about three times the size of the extant species and they are a sister group to the Chaoboridae (biting midges).
Food habits
Both male and female mosquitoes are nectar feeders, but the female is also capable of haematophagy (drinking blood). Females do not require blood for survival, but they do need supplemental protein for the development and laying of their eggs. Prior to sucking the blood, they inject a mild painkiller, which numbs the host to the pain from the bite. However, most humans can tell if a mosquito is biting them or not from a sensation of mild discomfort. The Toxorhynchites species of mosquito never drinks blood. This genus includes the largest of the extant mosquitoes, the larvae of which are predatory on the larvae of other mosquitoes. These mosquito eaters have been used in the past as mosquito control agents with variable success.
Adult [stage]
[...] Most mosquitoes stay fairly close to the ground and do not range too far from where they were born but may be dispersed long distances by wind. Mosquitoes are not strong flyers making only 1-2 km/h (1-1.5 mph) and an electric fan may make an effective mosquito screen. They feed mostly in the mornings and evenings and occasionally at night; avoiding the heat of the day. During the day they usually find somewhere cool to land.
Only female mosquitoes bite animals to get blood needed to produce eggs. Male mosquitoes do not bite, but both the male and female feed on the nectar of flowers for food. In most female mosquitoes, the mouth parts form a long proboscis for piercing the skin of mammals (or in some cases birds or even reptiles and amphibians) to suck their blood. As opposed to a syringe's typically smooth needle, the mosquito proboscis is highly serrated, which leaves a minimal number of points of contact with the skin being pierced -- this reduces nerve stimulation to the point where the "bite" is typically not felt at all. The females require protein for egg development and laying, and since the normal mosquito diet consists of nectar and fruit juice, which has no protein, most females must drink blood to lay eggs. Males differ from females, with mouth parts not suitable for blood-sucking.
The female mosquitoes locate their next blood donor victims primarily through scent. They are extremely sensitive to the carbon dioxide in exhaled breath, as well as several substances found in sweat and various body odors. They are believed to be able to track potential prey for tens of meters. Some people attract more mosquitoes than others, apparently based on how they "smell" to a mosquito. Mosquitoes can also detect heat, so they can find warm-blooded mammals and birds very easily once they get close enough. Repellants like DEET work by disorienting the mosquito as it gets close to its potential next meal but does not kill the mosquitoes. Surprisingly this works about 95% of the time.
Mosquitoes and health
Mosquitoes are a vector agent that carries disease-causing viruses and parasites from person to person without catching the disease themselves. Female mosquitoes suck blood from people and other animals as part of their eating and breeding habits. The female mosquito that bites an infected person and then bites an uninfected person might leave traces of virus or parasite from the infected person's blood. The infected blood is injected through, or on, the "dirty" probiscus into the uninfected person's blood and the disease is thus spread from person to person. When a mosquito bites, she also injects saliva and anti-coagulants into the blood which may also contain disease-causing viruses or other parasites. This cycle can be interrupted by killing the mosquitoes, isolating infected people from all mosquitoes while they are infectious or vaccinating the exposed population. All three techniques have been used, often in combination, to control mosquito transmitted diseases. Window screens, introduced in the 1880s, were called "the most humane contribution the 19th century made to the preservation of sanity and good temper."
Mosquitoes are estimated to transmit disease to more than 70 million people annually in Africa, South America, Central America, Mexico, Russia, and much of Asia with millions of resulting deaths. In Europe, Greenland, Canada, the United States, Australia, New Zealand, the UK, Japan and other temperate and developed countries, mosquito bites are now mostly an irritating nuisance; but still cause some deaths each year. Historically before mosquito transmitted diseases were brought under control they caused tens of thousands of deaths in these countries and hundreds of thousands of infections. Mosquitoes were shown to be the method that yellow fever and malaria were transmitted from person to person by Walter Reed, William C. Gorgas and associates in the U.S. Army Medical Corps in first Cuba and then the Panama Canal in the early 1900s. Since then other diseases have been shown to be transmitted the same way.
The mosquito genus Anopheles carries the malaria parasite (see Plasmodium). Worldwide, malaria is a leading cause of premature mortality, particularly in children under the age of five, with around 5.3 million deaths annually, according to Center for Disease Control. Most species of mosquito can carry the filariasis worm, a parasite that causes a disfiguring condition (often referred to as elephantiasis) characterized by a great swelling of several parts of the body; worldwide, around 40 million people are living with a filariasis disability. The viral diseases yellow fever and dengue fever are transmitted mostly by Aedes aegypti mosquitoes. Other viral diseases like epidemic polyarthritis, Rift Valley fever, Ross River Fever, St. Louis encephalitis, West Nile virus(WNV), Japanese encephalitis, LaCross encephalitis and several other encephalitis type diseases are carried by several different mosquitoes. Eastern equine encephalitis (EEE) and Western equine encephalitis (WEE) occurs in the United States where it causes disease in humans, horses, and some bird species. Because of the high mortality rate, EEE and WEE are regarded as two of the most serious mosquito-borne diseases in the United States. Symptoms range from mild flu-like illness to encephalitis, coma and death. [4] Viruses carried by arthropods such as mosquitoes or ticks are known collectively as arboviruses. West Nile virus was accidentally introduced into the United States in 1999 and by 2003 had spread to almost every state with over 3,000 cases in 2006.
A mosquito's period of feeding is often undetected; the bite only becomes apparent because of the immune reaction it provokes. When a mosquito bites a human, she injects saliva and anti-coagulants. For any given individual, with the initial bite there is no reaction but with subsequent bites the body's immune system develops antibodies and a bite becomes inflamed and itchy within 24 hours. This is the usual reaction in young children. With more bites, the sensitivity of the human immune system increases, and an itchy red hive appears in minutes where the immune response has broken capillary blood vessels and fluid has collected under the skin. This type of reaction is common in older children and adults. Some adults can become desensitized to mosquitoes and have little or no reaction to their bites, while others can become hyper-sensitive with bites causing blistering, bruising, and large inflammatory reactions.
Male mosquitoes are distinctly smaller than females, with features such as feathered antennae and having no sound during flight. Female mosquitoes in flight emit a distinctive high-pitched buzz, which can interrupt sleep.
Treatment of mosquito bites
Visible, irritating bites are due to an immune response from the binding of IgG and IgE antibodies to antigens in the mosquito's saliva. Some of the sensitizing antigens are common to all mosquito species, whereas others are specific to certain species. There are both immediate hypersensitvity reactions (Types I & III) and delayed hypersensitivity reactions (Type IV) to mosquito bites.
There are several commercially available anti-itch medications. These are usually orally or topically applied antihistamines and, for more severe cases, corticosteroids such as hydrocortisone and triamcinolone. Many home remedies are ineffective against itching, including calamine lotion, baking soda and scratching.Don't scratch yourself too much, now...
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Post by killerzzz on Jul 10, 2007 5:56:59 GMT
Alright guys, I'd like to put my philosophy on these vermin, parasites. Ok. Nature. Natural order. Microbes are eaten by little bugs and tiny animals/fish, those are eaten by bigger ones, until we get to the top of the food chain. Usually, the higher on the food chain, the less babies, so that natural death and death from battle with other predators, can keep a nice balance. And, if I must mention it, plants eat some microbes, herbavores eat plants, then they get eaten by predators, and so on. So, what could one of the reasons for parasites be? Well, they could just be another predator, keeping the natural balance. But what about humans? We work so hard to delay death and we are multiplying and multiplying, overflowing the natural order. Perhaps these parasites, and even desiease (pretty much parasites too), are here to cut down the world's population. To keep it at bay. That may even be the reason for great plagues and epidemics (which can often go hand-in-hand with parasites who help the spreading), that wipe out thousands or millions of lives. So? Parasites (/sickness) are the "human solution" I hear about every once in a while. Other versions of the "human solution" include some psychopathic mass murder plans found in fiction; but lets just call the buggers the "actual one". I'm not saying that they are a "solution" and I find the mentality of that creepy, but it seems that indeed they are here to somewhat control our ever-growing ever-striving population. Yes? No? Maaaaybe? Killerzzz
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Post by killerzzz on Aug 7, 2009 15:20:25 GMT
Remember this ole thread? Okay, show of hands, who wants to throw up? Any takers? Yes? No? Then read on. >: ) The Botfly. The little bastard who puts its babies IN YOUR SKIN! Ain't it the truth, Wiki? The botfly is a family of Oestroidea. It is one of several families of hairy flies whose larvae live as parasites within the bodies of mammals. There are approximately 150 known species worldwide.
Only one bot fly species attacks humans, the Dermatobia hominis.And it can do it many ways too! One: momma lands and puts the eggs right in your skin, which immediately hatch when they feel the warm squishy goodness of your flesh. Two: momma gets the help of a smaller fly. The smaller fly is firmly held by the botfly female and rotated to a position where the botfly attaches some 30 eggs to the body under the wings. Larvae from these eggs, stimulated by the warmth of a large mammal host, drop onto its skin and burrow underneath.Three: momma gets eaten, or you eat momma's helper, or you lick your fur where some eggs might have fallen. Oh wait, this mostly happens with animals. Wiki can get lengthy while describing the nastiness of this method, so let me help instead! ;D The ingested eggs hatch in your intestines or somewhere on the way, then the larvae 'migrate' (nice word, Wiki) to the surface of your skin. In other words they squirm around INSIDE you, all the way up your body, until the push their way through your blood and guts and get to your skin. This is what I'm talking about. Save the animals! Removal of the eggs (which adhere to the host's hair) is tricky, since the bone and tendons are directly under the skin on the cannon bones: eggs must be removed with a sharp knife (often a razor blade) or rough sand paper, and caught before they reach the ground. During this process the human can also become infected. Bots can be controlled with several types of dewormers, including dichlorvos, ivermectin and trichlorfon.There's more in the Wiki page telling of all the side-effects, diseases, deaths of animals and whatnot. And places where the flies are found. And here is such a nasty picture of some sort of similar if not the same fly infection that I have to put it in a link. Wikipedia is laughing at me cuz it popped this image out when I didn't expect it. =_= Oh, moar human cures! Botflies can, on occasion, lay their eggs on humans. The larva, because of their spines, then pose an extremely painful sub-epidermal condition. Removal processes include placing raw meat on to the area, which in theory will coax the larva out. Another option is to use the tree sap of the matatorsalo, found in Costa Rica, which will kill the larva, yet leave its body in the skin. Additionally, one can attempt to seal the breathing hole of the larva with nail polish, vaseline or adhesive tape and then, after a day, squeeze out the suffocated, dead larva.And to top it all off, who wants to watch a video of a man who got some of these maggots in his skin in Panama because a dumb-ass mosquito bit him and had been carrying some eggs. Happy Trails! Killerzzz
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Post by Hildor on Aug 7, 2009 19:00:20 GMT
A teacher once told us about a very cool parasite. The critters starts it's life cycle by working itself INTO the brains of an ant. In that way it literally controls the ant to move up to the end of a grass sprite and there it blocks it's limbs, so that it can't move away. Sitting on top of the grass sprite, the ant has a large chance to get eaten by a cow (together with the grass ofcourse). And form there on, the parasite develops into a tapeworm in the cow's intestinges. Now if that isn't the coolest way ever for a parasite to reach it's host I might try some internet searching to find more information about that creature if it exists.
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Post by LaFille on Aug 9, 2009 1:24:22 GMT
Yeah, it would indeed exist; IIRC there was a thread posted about it here somewhere... There's also an article in the National Geographic website here. Alright guys, I'd like to put my philosophy on these vermin, parasites. Ok. Nature. Natural order. Microbes are eaten by little bugs and tiny animals/fish, those are eaten by bigger ones, until we get to the top of the food chain. Usually, the higher on the food chain, the less babies, so that natural death and death from battle with other predators, can keep a nice balance. And, if I must mention it, plants eat some microbes, herbavores eat plants, then they get eaten by predators, and so on. So, what could one of the reasons for parasites be? Well, they could just be another predator, keeping the natural balance. But what about humans? We work so hard to delay death and we are multiplying and multiplying, overflowing the natural order. Perhaps these parasites, and even desiease (pretty much parasites too), are here to cut down the world's population. To keep it at bay. That may even be the reason for great plagues and epidemics (which can often go hand-in-hand with parasites who help the spreading), that wipe out thousands or millions of lives. So? Parasites (/sickness) are the "human solution" I hear about every once in a while. Other versions of the "human solution" include some psychopathic mass murder plans found in fiction; but lets just call the buggers the "actual one". I'm not saying that they are a "solution" and I find the mentality of that creepy, but it seems that indeed they are here to somewhat control our ever-growing ever-striving population. Yes? No? Maaaaybe? Killerzzz Parasitism is a form of predation that just doesn't involve the death of the host/prey to achieve the parasit's purpose (even if the infestation/predation can indeed cause an eventual death if too severe/aggressive). From a survival/reproduction point of view, this is a way with much more advantages than straight predation since it allows the parasit to feed/spread without significantly destroying the resource it depends on. The most successful parasites are those that have relatively benign impacts on their hosts and the means they have are sometimes fascinating, like natural analgesics, antibiotics that they secrete to "secure" the wounds they're doing. That's why parasits in general are so 'successful'; killing what one feeds on doesn't offer much advantage if you can coexist with it. Besides, in biology, the term "predation" also includes organisms feeding on plants; parasitism too. When we gather our carrot, we're predators; when we pick up our branch of rhubarb, we're parasites. Our consumption of dairy products makes us parasites too. Edit: On population 'regulation', yeah, diseases and parasites are a factor... But even without, regulation would eventually happen and be caused by lack of food/habitat resources once the living environment would be saturated/spoiled (if its expansion isn't possible). Until we transcend that condition somehow, I think we're bound by our material limits.
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