an itchy swimmer or dermatitis serceran , is a short-term immune reaction that occurs in the human skin that has been infected by schistosomatidae carried by water. The symptoms, which include itching, the onset of papules, generally occur within hours of infection and generally do not last more than one week. This is common in freshwater, brackish and marine habitats around the world. Incidence may increase, although this can also be associated with better monitoring. However, this condition has been regarded as an emerging infectious disease.
There is no permanent effect for people of this condition. Osteroksin given orally, an antihistamine, is sometimes prescribed to treat swimmer's itching and similar skin allergic reactions. In addition, bathing with oatmeal, baking soda, or Epsom salts can also relieve symptoms.
Video Swimmer's itch
Penyebab
Swimmer's itchiness may have been present during humans. This condition was known to exist as early as 1800s, but it was not until 1928 that a biologist discovered that dermatitis was caused by a larval stage of a group of flatworm parasites in the Schistosomatidae family. Genera most often associated with itchy swimmers in humans is Trichobilharzia and Gigantobilharzia. It can also be caused by schistosome parasites of non-avian vertebrates, such as Schistosomatium douthitti , which infect snails and rodents. Other taxa reported to cause a reaction include Bilharziella polonica and Schistosoma bovis . In marine habitats, especially along the coast, itchy swimmers can occur as well.
This parasite uses freshwater snails and vertebrates as hosts in their parasite life cycle as follows:
- After the schistosome egg is immersed in water, life, no eating, the free life stage known as miracidium appears. Miracidium uses cilia to follow the thoughtful chemical and physical cues to increase his chances of finding the first middleman in his life cycle, a freshwater snail.
- After infecting snails, he develops into sporocyst mothers, who in turn undergo asexual reproduction, produce large numbers of female sporocysts, which asexually produce a short-lived, sercaria-free lifestyle.
- Serkaria uses frill-like tails (often branched off in the genera that cause swimmer itching) to swim to the surface of the water; and uses various physical and chemical cues to find the next and last (definitive) host in the life cycle, a bird. This larva can inadvertently come into contact with the skin of a swimmer. Serkaria penetrates the skin and immediately dies on the skin. Sercaria can not infect humans, but they cause an inflammatory immune reaction. This reaction initially causes itchy spots on the skin. Within a few hours, these spots become increasingly itchy papules. Each papule corresponds to the location of a single parasitic penetration.
- After finding the bird, the parasite penetrates the skin (usually the foot), dropping the branched tail in the process. In the circulatory system, the adult worm (schistosomula) develops into adult and female worms, mating and migrating through the host's circulatory system (or the nervous system in the case of T.regenti ) to the final location (the vein giving eating gastrointestinal tract) in the host's body. There they lay their eggs in small blood vessels in the intestinal mucosa from which they make their way into the intestinal lumen, and are thrown into the water when the bird defecates. One European species, Trichobilharzia regenti , actually infects nasal tissue and hatching bird larvae from eggs directly in the tissues during drinking/feeding of infected birds.
Maps Swimmer's itch
Risk factors
Humans are usually infected after swimming in lakes or other bodies of slow moving water. Some laboratory evidence suggests that snails remove most intense cercoles in the morning and on sunny days, and exposure to water in these conditions can increase the risk. Swimming duration is positively correlated with an increased risk of infection in Europe and North America, and shallow coastal waters may have higher census density than offshore open waters. The terrestrial wind is thought to cause caesarean to accumulate along the coastline. Studies of infested lakes and epidemics in Europe and North America have found cases where the risk of infection appears to be evenly distributed around the edges of the water body as well as examples where risks increase in "hot spots" of endemic swimmer hypothesis. Children may become more infected and more intense than adults but this may reflect their tendency to swim for longer periods on the beach, where cercane also concentrates. The stimuli for serceral penetration into the skin of the host include unsaturated fatty acids, such as linoleic and linolenic acids. These substances occur naturally in human skin and are found in lotion and sun cream based on plant oils.
Control
Various strategies targeting mollusks and hosts of schistosomes birds, have been used by lakeside residents in the North American recreation area to handle swimmers' itching outbreaks. In Michigan, for decades, authorities used copper sulphate as a molluscicide to reduce the host population of snails and thus the swimmer's itching incident. The results with this agent have been convincing, probably because:
- Snails become tolerant
- Local water chemistry reduces the efficacy of molluscicide
- Local stream pass it on
- Population of adjacent snails refilled the treated area
More importantly, perhaps, copper sulfate is toxic to more than molluscs, and its effect on aquatic ecosystems is poorly understood.
Other methods targeting snails, mechanical disturbance of snail habitats, have also been tried in several areas of North America and Lake Annecy in France, with promising results. Several jobs in Michigan show that praziquantel administration in hatching waterfowl can reduce the rate of local swimmer's itching in humans. Working on schistosomiasis shows that topical waterproof applications from common DEET repellent insects prevent schistosomes from penetrating the skin of mice. Public education on risk factors, a good alternative to the previously mentioned interventionist strategy, can also reduce human exposure to cercaria.
See also
- Schistosomiasis
- Sea lice
References
External links
Source of the article : Wikipedia
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