Giardiasis - Symptoms, Prophylaxis, and Treatment - Essay Example

? Giardiasis Giardiasis Giardia is a parasite that scientists have described as the causative agent of the diarrheal infection named giardiasis. Giardiasis is a common infection in many parts of the globe, because of the fact that Giardia parasites occur in all continents on soils, water, and surfaces. The Center for Disease Control and Prevention (CDC) has focused on intensive research in its bid to prevent the prevalent infection in many lands. This paper will describe the parasite that causes Giardiasis, symptoms of the infection, prophylaxis, and treatment. Identification of the Disease Giardiasis is an infection of the gastrointestinal tract. Other common names are lambliasis and beaver fever. After infection with the parasite, the individual suffers a diarrheal infection after the first week (Berger, 2011). The infection has been categorized as a global problem because of its prevalence in many parts of the world. The name ‘beaver fever’ emerged after research indicated that the disease was common amongst backpackers and campers. The science community ascertained the link between the giardia parasite and the diarrheal infection in the 1970s, although they had known the parasite since the 17th century. The diarrheal infection does not present any mortality rates unless in individuals exhibiting a compromised immune system. Many of the people infected with the parasite have been reported to exhibit minimal symptoms. Other researches indicate that there are cases that are more serious, and the infection can cause diarrhea for about two weeks. Description of the Organism The parasite giardiasis is the causative agent of a common diarrheal infection that has existed for a long time. Van Leeuwenhoek discovered the parasite in 1681. Using microscope, he highlighted that the parasite exhibited slow movement, and had flagella that facilitated the movement. He also classified the parasite as one of the simple eukaryotes. Other scientists developed interest in the parasite in the centuries that followed, and sought to describe it further. From advanced studies, it became evident that Leeuwenhoek had observed the parasites in the trophozoite phase. This was after the discovery that the parasite exhibited two different stages of life. According to the findings of 1880, it became evident that the parasite had both the trophozoite cysts stages (Parker & Parker, 2004). During the cyst stage, the flagella were invisible. Scientists have described the cyst stage as a dormant phase in which the parasite forms a protective wall around itself. This wall makes the parasite resistant to temperature changes, osmotic differences, pollution, and nutritional shortage. Further studies revealed that the cysts have the potential to remain viable for long periods without the having access to water and food. Usually, this serves as the infective stage of the parasite as many people get the infection from swallowing water infested with cysts. After entry into the gastrointestinal tract, the parasite moves from the cyst into the trophozoite stage. In this stage, the parasite engages in obtaining nutrients in the intestines and reproduces. The flagella are visible during this phase of Giardia (Russell and Cohn,2013). Biologists have described the trophozoite as having the ability to attach to the intestinal villi, where they depend on mucosal secretions for nutrition. In size, the trophozoites are 9-21 micrometers long, 5-15 micrometers wide, and 2-4 micrometers in thickness. When viewed under the microscope, they depict a pear shape that has a round end on the anterior side, two nuclei, as well as two distinctive median rods. The trophozoite also exhibits motion with the four pairs of flagella evident on each cell. In its ventral body, the organism has an adhesive disc that facilitates its attachment to the intestines. The organism reproduces by asexual binary fission, with the production of a new generation every five hours. Some trophozoites detach themselves from the intestines and find their way into the fecal stream, where they transform into cysts. The Giardia protozoan family consists of about six species that are responsible for causing diarrheal infection in different animals. Scientists have identified Giardia duodenalis as the causative agent of disease in mammals. This species also bears the name Giardia intestinalis after taxonomists discredited Giardia Lamblia that was in wide usage previously, as part of paying tribute to the scientist who described advanced features of the parasite. Other species include Giardia agilis causing infection in amphibians, while Giardia ardeae and Giardia psittaci commonly infesting birds. In addition, Giardia Muris is the species found in rodents with Giardia Microti in muskrats and Giardia varani in reptiles. Scientists have also described Giardia duodenalis that has the capacity or infecting people. This species entails about seven different assemblages described as having the potential to cause disease. Lifecycle of Giardia Retrieved from http://www.cdc.gov/parasites/giardia/biology.html Symptoms of Giardiasis Many people infected with Giardia duodenalismay present limited symptoms, with cases of infection being asymptomatic at times. The incubation period of the parasite after infection is usually between one to four weeks. Diarrhea may exhibit itself within the first week in some individuals, while it may manifest itself 25 days. Experts have highlighted that in such cases the individual may often get rid of the cysts in a spontaneous manner. Asymptomatic cases do not cause any serious diarrhea. However, symptomatic cases may cause either mild or severe diarrheal infection. Some people infected with the parasite usually exhibit acute diarrhea, defined by loose stool that has a foul smell. Other cases may persist to chronic levels. The stool in this case exhibits a greasy appearance and may contain bloodstains. The individual may also experience abdominal cramping, pain, nausea, frequent bloating, flatulence, anorexia, weight loss, dehydration, and vomiting. Dehydration is a common symptom in infants with persisted diarrhea because of the loss of fluids. Other infected individuals experience fever at the onset of the infection. Progressed diarrhea may lead the individual to experience fatigue. In studies involving elderly persons, it became evident that they exhibited weight loss, anorexia, and anemia in higher frequencies than in other infected people. Infections may last only a few weeks although serious cases may persist for numerous months and years(UnitedStates Centers for Disease Control, 2004). In such chronic cases of giardiasis, the diarrhea may be continuous, sporadic, recurrent,or intermittent. Other biologists have highlighted that some individuals present usual bouts of diarrhea accompanied by constipation even when diarrhea has stopped. Many patients have mentioned that abdominal pains usually persist even when diarrhea is minimal. Chronic cases of giardiasis usually culminate in mal-absorption in the intestines, a case that may limit the availability of disaccharides and vitamins. Cases of mal-absorption become manifest through the apparent weight loss that results accompanied by debilitation. It is possible for chronic giardiasis to occur even in immuno-competent people although such cases are rampant in people with compromised immune systems. Immune compromising infections include congenital hypogammaglobulinemia, Human immune deficiency virus, lymphoma, and other conditions that cause protein-calorie malnutrition. Giardiasis causes disaccharide incompetence manifesting itself as a deficiency of lactose in the body. Experts have identified this as the worst complication of the infection. This intolerance can last for several weeks even after medical intervention clearing the parasite from the body. Lactose intolerance resulting from giardiasis presents symptoms that resemble those exhibited by the infection. These include diarrhea, frequent bloating accompanied by abdominal cramps. In advanced cases, vitamin B deficiency may result, while infants may present growth retardation.in some regions, researchers have identified that giardiasis has a linkage to irritable bowel syndrome. Case reports from such areas indicate that the infection may also present symptoms such as bronchospasm urticarial, reactive arthritis and pruritus, which are extra intestinal symptoms. Mode of Transmission Giardiasis transmission occurs through several ways that link the fecal-oral systems. Stool from infected people has numerous trophozoites and cysts(United States Centers for Disease Control, 2004). As mentioned earlier, the cysts are the infective ones because the trophozoites die after a short duration outside the living body. The stool from such individuals may contaminate water sources. In other cases, an individual; may come into contact food contaminating it if he does observe sanitary hygiene. Anyone taking in such water or foodstuffs ingests a number of the cysts. When these cysts get into the intestines, they undergo a transformation that involves losing the protective wall and becoming trophozoites. Since the trophozoites have the potential to reproduce, they multiply and eventually cause diarrhea. Treatment and/or Prophylaxis After some of the symptoms described above become evident in an individual, there is need to consult a medical practitioner for diagnosis. It is easy to diagnose the infection through direct observation of a stool smear from fresh feces. Staining may serve to make visualization easier, and trophozoites are highly visible in fresh smears. In cases where symptoms are evident but stool samples do not confirm the presence of trophozoites, it is rational carry out an observation of the intestinal content to establish the presence of Giardia. Researchers prefer to use molecular techniques such as polymerase chain reaction and enzyme-linked immunosorbent assays or serology techniques in diagnosis. After positive diagnosis, there is need for medical intervention. This usually involves the use of either of several drugs available for treating giardiasis. Some of these drugs include nitroimidazole derivatives, acridine dyes, and benzimidazole compounds. In humans; the most common medical intervention involves the use of metronidazole and tinidazole (Ortega-Pierres, 2009). The prescription of furazolidine and paromomycin also applies is some cases. In addition, infected individuals may require fluids and electrolyte management. There is need to seek additional medical help in cases of lactose intolerance and other complications. Resistance of some of the drugs highlighted may cause recurrence of diarrhea, and it is proper to seek medical care if that happens. Experts have outlined numerous strategies that can reduce the rates of infection. One of these strategies is ensuring that drinking water is hygienic by treating water sources. Water treatment by chlorination is a common trend in many regions, and this reduces the risk of infection(North Dakota, 2004). There also call for the need to disinfect swimming pools with the right amount of disinfectant while swimmers should refrain from swallowing the water. Other hygienic practices outlined as preventive measures include showering prior to entry into the pool. Observation of basic hygiene such as hand washing after the use of lavatories, and washing foodstuffs before use can minimize infection. Infected people should not access swimming pools or other recreational areas until the clearance of all the symptoms. Current Research Activity on this Disease The center for Disease Control and Prevention has embarked on different research projects on giardiasis(UnitedStates Centers for Disease Control, 2004). One of these surrounds the production of vaccines against the causative agent. There are multiple challenges hindering the development of vaccines, and the most outstanding of these is the fact that the parasite is highly adaptive, with a remarkable ability to later its protein coating instantly (Luja?n, 2011). Other researches surround the possibility of zoonotic transmission. Such projects seek to clarify categorically whether species of giardia found in animals cause infection in humans. Other organizations have focused on establishing more data on the molecular attribute of the parasite. Significance of the Research The above-mentioned research projects are highly significant and justifiable. With the rampant infection of people in different parts of the world with giardiasis, the globe has been losing millions invested in medication (UnitedStates Centers for Disease Control, 2004). Moreover, the infection can cause mortality in infants, the elderly and those with compromised immune systems. Therefore, the research on vaccines can yield effective preventive measures, and reduce the rate of infection significantly. With humans having a close relationship with other animals infected by other giardia species, there is the worry of zoonotic transmission as has occurred with other diseases (Yagaand, Lymbery, 2010). The research on this issue seeks to clear such doubts. Molecular characterization of the parasite will help in designing effective medical strategies of intervention. Conclusion As described above, giardiasis is a common diarrhea infection in different parts of the globe. Giardia species usually cause the infection, with scientists having isolated about six species that cause infection in different animals. Giardia duodenalisis one of the species that cause infection in humans. The parasite exhibits two phases in its lifecycle namely cysts and trophozoites. The disease presents certain symptoms as highlighted, and with treatment, the parasite dies. References Berger, S. A. (2011). Giardiasis: Global status. Los Angeles, Calif: Gideon Informatics. Luja?n, H. D. (2011). Giardia: A model organism. Wien [u.a.: Springer. North Dakota. (2004). Giardiasis.Bismarck, N.D.: North Dakota Dept. of Health. Ortega-Pierres, G. (2009). Giardia and cryptosporidium: From molecules to disease.Wallingford, UK: CABI. Parker, P. M., & Parker, J. N. (2004).Giardiasis: A medical dictionary, bibliography, and annotated research guide to Internet references. San Diego, CA: ICON Health Publications. Russell, J., and Cohn,R. (2013).Giardiasis.S.l.: Book On Demand Ltd. UnitedStates Centers for Disease Control (2004).Parasite and Health. Retrieved on 16th October 2013 from http://www.cdc.gov/dpdx/HTML/Frames/G-L/Giardiasis/body_Giardiasis Yaga, R. and, Lymbery, A. Ryan U. (2010).Identification of zoonotic Giardia genotypes in fish.Int J Parasitol, 40(7), 779-85. Read More