The main species that infect people are the roundworm (Ascaris lumbricoides), the whipworm (Trichuris trichiura) and hookworms (Necator. diminish Ascaris suum infection in heavily infected pigs; the .. Ascaris lumbricoides.(Laporan. Penelitian) Makalah Seminar sapi Bali. Indonesia Australia. In Indonesia, the nematode intestine is still a public health problem is Ascaris lumbricoides, hookworm and Trichuris trichi-ura. Soil, vegetables and water is an .
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Soil-transmitted helminths STHs form one of the most important groups of infectious agents and are the cause of serious global health problems.
The most important STHs are roundworms Ascaris lumbricoideswhipworms Trichuris trichiura and hookworms Necator americanus or Ancylostoma duodenale ; on a global level, more than a billion people have been infected by at least one species of this group of pathogens. This review explores the general concepts of transmission dynamics and the environment and intensity of infection and morbidity of STHs.
The global strategy for the control of soil-transmitted helminthiasis is based on i regular anthelminthic treatment, ii health education, iii sanitation and personal hygiene and iv other means of prevention with vaccines and remote sensoring.
The reasons for the development of a control strategy based on population intervention rather than on individual treatment are discussed, as well as the costs of the prevention of STHs, although these cannot always be calculated because interventions in health education are difficult to measure.
Prevention of Soil-transmitted Helminth Infection
An efficient sanitation infrastructure can reduce the morbidity of STHs and eliminates the underlying cause of most poverty-related diseases and thus supports the economic development of a country. Soil-transmitted helminths STHs form one of the most important groups of infectious agents and are the cause of serious global health problems; more than a billion people have been infected by at least one species of this group of pathogens.
Global estimates of number of soiltransmitted helminth infections by region millions of cases [ 2 ]. Geohelminths are more prevalent among children living in conditions of poor sanitation, and their impact on morbidity and mortality is more severe in malnourished populations.
These few seriously infected individuals are at a higher risk of disease and are also the prime source of environmental contamination. In the developing world, inadequate water supply and sanitation, as well as crowded living conditions, combined with lack of access to health care and low levels of education, make the poor particularly susceptible to infection and disease, including STHs.
The STHs vary greatly in size, and female worms are larger than males. The STH infection life cycle follows a general pattern; the lumbrucoides in adult stages inhabit part of the host intestine A.
Adult worms survive for several years and produce large numbers of eggs. Eggs can remain viable in the soil for several months A. Infection occurs through accidental ingestion of eggs A. The dynamic processes involved in STH nakalah free-living infective stages of development and survival depend on the ascaaris environmental conditions; climate is an important determinant of transmission of STH infections, with adequate moisture and warm temperature essential for larval development in the soil.
Although seasonal dynamics in transmission may occur, such fluctuations may be of little significance to the overall parasite equilibrium within communities. There is evidence that individuals with many helminth infections have even worse infections with STHs.
These few heavily infected individuals are at a higher risk of disease and are also the prime source of environmental contamination. Generally only the STH infections of moderate and high intensity in the gastrointestinal tract produce clinical manifestations, with the highest-intensity infections has been mostly common in children. Each of the STHs produces characteristic disease syndromes. Since morbidity from these infections and the rate of transmission are directly related to the number of worms harbored in the host, the intensity of infection is the main epidemiological index used to describe soil-transmitted helminth infection.
Intensity of infection is measured by the number of eggs per gram of feces, generally by the Kato-Katz fecal thick-smear technique. Whether such age dependency indicates changes in exposure, acquired immunity or a combination of both remains controversial. The STHs are more frequently found among children living in conditions of poor sanitation, and their impact on morbidity and mortality is more severe in malnourished populations. A high prevalence of STHs, when combined with poor hygiene and malnutrition, is an indicator of a country’s future problems, indicating that priority be given to eradicating STHs worldwide.
Such children experience malnutrition, stunted growth, mental retardation, as well as cognitive and learning deficiencies. Large-scale environmental sanitation programs are complex, making interventions directly aimed at the transmission of STHs challenging to implement.
Amongst these are public investment in sewage networks and a collective will on the part of individual households to invest in a toilet and connect it to this network. The world health organization WHO [ 1 ] has recommended three interventions to control morbidity due to STH infections: Regular drug treatment represents the main approach for infection control in areas where infections are intensely transmitted, where resources for disease control are limited and where funding for sanitation is insufficient.
Drug treatment can be administered in the community using alternative approaches — the treatment is offered to the entire community, irrespective of age, sex, infection status and any other social characteristics universal treatment ; the treatment is targeted at population groups, which may be defined by age, sex or other social characteristics, irrespective of the infection status targeted treatment ; and selective treatment representing individual-level administration of anthelminthic drugs, where selection is based on diagnosis to detect the most heavily-infected people who will be most at risk of serious morbidity and mortality.
In accordance with theWHO[ 22 ], the recommended drugs for for use in public health interventions to control STH infections are:.
Evidence suggests that mass delivery of deworming is preferable on efficacy, economic and equity grounds for approaches that require diagnostic screening. Frequency of regular treatment should vary according to the intensity of transmission and rates of re-infection. These factors must be considered in relation to the resources available and the cost involved in drug purchase and distribution.
Helminths in different areas of the world have different levels of egg output,[ 28 ] so the thresholds proposed by the WHO are not rigid and should be adjusted for the local situation.
The World Health Assembly in ascaaris a strategy for the prevention and control of schistosomiasis and soil-transmitted helminthiasis in high-transmission areas. For long-term sustainability, environmental health will be required improving access to safe water and sanitation lumbricooides improved hygienic behavior through health education. Health education aims to improve health and increase hygiene awareness and to change health-related behavior in the population.
For diseases related to poverty, such as STH infections, the suggested solution might not be available or might be too expensive to adopt.
Deprived communities understand the importance of the safe disposal of fecal matter and of wearing shoes, but poverty often hinders the construction of latrines and the purchase of shoes. The prevalence of STHs in the community can be used as an indicator of the conditions of living, environmental sanitation, level of education and the socioeconomic status of the community. Providing information on the disease and the possible adoption of preventive measures frequently results in an increase in knowledge but not necessarily in behavioral change.
Educational materials posters, leaflets, radio and video messages have been traditionally used to transmit and disseminate health-related messages, but strategies imported from the private sector are increasingly being advocated for their potential value in crafting and disseminating health-related messages.
The knowledge of, and motivation for, behavioral change must be sustained by making available proper facilities for excreta disposal. Frequently, in STH-endemic areas, latrines are not available or are not in sufficient numbers to meet the needs of the population. Romotion of latrine maintenance and use, washing of hands and proper food handling have benefits that go beyond the control lukbricoides STH infections. From this perspective, it is reasonable to include health education in all STH-control programs, wherein the health education message can be provided in a simple and inexpensive way.
Health education messages can be delivered by teachers in schools, thereby fostering changes in health-related behavior in children, which in turn involves their parents lumbricoidess guardians. Human STHs are fecal-borne infections, and transmission occurs either directly hand-to-mouth or indirectly through food and water. Sanitation in the context of economic development is the only definitive intervention that eliminates these infections.
Improvement of sanitation standards always has a repercussion on infection and maka,ah infection levels. Agglomeration and the type of excreta-disposal facility were the only significant predictors of re-infection in lumbricoidew conducted in the West Indies, showing that the prevalence of STH infections was significantly lower in areas with better sanitation.
In Zimbabwe, despite the marked increase in the number of latrines, no relationship was found between hookworm re-infection intensities and the availability of latrines in individual farms. Sanitation is inadequate in most cities ascari developing countries, with major effects on STH mzkalah. In this situation, piped sewers are an appropriate solution, and it is questionable as to whether efforts should focus on systems based on onsite solutions, such as latrines.
In a meta-analysis study,[ 45 ] data suggested that sewerage typically has a positive effect on enteric infectious disease burden. A systematic review and meta-analysis[ 46 ] suggested that water, sanitation, and hygiene interventions as well as their combination, are effective at reducing diarrheal illnesses and STH infections.
Prevention of Soil-transmitted Helminth Infection
This review identifies many research questions that need more attention: In another review,[ 47 ] consistent findings 30 studies of intervention and 24 observational studies during a year period lymbricoides the conclusion that hygiene interventions other than infrastructure implementation are important for preventing infections, particularly the STH infections. Environmental factors such as water lumbridoides for domestic and personal hygiene, sanitation and housing conditions; and other factors such as socioeconomic, demographic and health related behavior are known to influence this infection.
Two principal factors in maintaining endemicity of these helminths are favorable qualities of the soil and the frequent contamination of the environment by human feces. Their transmission within the community is predominantly related to human habits with regard to eating, defecation, personal hygiene and cleanliness.
Sanitation factors such as the reliability of water supply, frequency of rubbish collection and proximity to overflowing or lumricoides sewage are not under the control of individual households.
These do not reflect personal hygiene, and their significance suggests that the impact of environmental sanitation on health could have been greater if the governmental systems had been properly operated makqlah maintained.
Improved disposal of excreta offers a more sustainable method of control, among many other benefits. The effect of improved sanitation is slow to development and may take decades to achieve a measurable impact.
Often, the high costs involved prevent the provision of sanitation to the communities most in need, and sanitation does not become effective until it covers a high percentage lumbricoieds the population.
Vaccine makalaj has driven the field of immunology since it incorporates the selection and presentation of benign antigens or attenuated pathogens to lumbricoide an acquired protective response. Vaccination has proven to be the most cost-effective and efficient procedure for disease management.
The need to control chronic and emerging diseases and bio-security concerns stimulate demand for new vaccines. Helminths are exquisitely adapted to evading and modulating the mammalian immune response; and interestingly, similar evasion mechanisms can be shared among distantly related species. This begs the obvious question of whether this ability ascais ever be exploited for therapeutic purposes. The association between intestinal parasites and atopy is not limbricoides.
Various results indicate an inverse relationship where in individuals infected with STHs are less susceptible to allergic disorders, as a result of immunological mechanisms that remain unknown. Immunological studies of the mechanisms by which early exposure to geohelminth infections affects immune polarization to inhalant allergens are likely to provide important insights into the early makaalh of the immune response and may lead to the design of novel interventions for the prevention of STH infections.
This being the case, nakalah dosing of a helminth or products thereof to relieve fulminant inflammatory disease in an adult may be relatively ineffective. The patient’s immune repertoire, both adaptive and innate, has already been shaped by the absence of parasite antigens and is subject only to relatively lumbricokdes perturbations. Early enteric exposures to STH infections in infancy may provide important maturational and regulatory signals for the developing immune response that allows it to control allergic inflammation directed against both parasitic and environmental aeroallergens.
Typically, STH infections are chronic in endemic areas, and, as with other helminth parasites, it is likely that geohelminths have developed ways of modulating the host immune response to permit adult development and survival.
Likewise, the human host may have developed mechanisms to limit the pathology associated with the long-term presence of these highly allergenic parasites.
Experimental vaccine development under controlled conditions in the laboratory requires field testing to isolate important modulating factors. An underlying parasitic infection is a profound, albeit reversible, modifier of vaccine efficacy.
Studies have inv estigated spatial patterns of STH infections[ 186162 ] and other helminths. These studies have focused on the use of RS data to identify ecological correlates of infection and develop statistical models of disease risk. Geographical distributions are continually updated as new epidemiological data are collected, and as intervention reduces the prevalence of infection. Analysis of the cost-effectiveness of the tools, which is germane to their long-term and sustainable use, is currently underway.
Experiences in Uganda demonstrate the usefulness of remote sensoring GIS or RS as geographic decision-making tools for implementing helminth control on both national and local scales. An important emerging trend is that national governments are beginning to use this approach for designing and developing sustainable national programs. The results from the survey helped the government plan the country’s school-based control program, and resulted in significant cost savings for the program since it identified the need to target far fewer schools than had first been anticipated.
The national survey revealed that infection was highly focal and that deworming interventions could be precisely targeted, with significant savings in financial and technical resources.
The cost-benefits of the control measures for morbidity due to STH infections are influenced by the ecological and environmental situation, by the availability of local anthelminthic drug production facilities and by the presence of infrastructure and facilities that can be used to reach the high-risk groups: The infrastructure for the delivery of such a package of health care to millions of poor people already exists in many endemic areas through primary health care provision, public and private schools, faith-based organizations and social institutions.
In deprived communities, where sanitation is practically nonexistent and the prevalence and intensity of infection are high, a suitable infrastructure such as the school system or a national immunization day should be used to distribute at least regular treatment to the groups at risk. The cost of adding this intervention is normally marginal.
The average cost per child per year is 70 US cents: In Cambodian schools, deworming is promoted by means of a school kit, which contains deworming tablets, health education posters and pamphlets for teachers, games and attractive pictures giving simple messages on how to prevent infection.