Chagas Disease in Chile-Free-Sample for Students-Myassignment

Question: Choose a particular tropical disease or Condition which is associated with significant morbidity and mortality in a least one tropical and developing country, and apply principles for prevention and control to this disease. Answer: Ecology and Epidemiology of Chagas Disease Chagas disease is the tropical disease that has been selected for this assignment. Chagas disease is caused by species of triatomine vectors. In Chile, there are several species of triatomine including T. infestans, M. spinolai, M. parapatrica and M. gajardo (1). The primary sylavitic species is the M. spinolai. M. spinolai is found in rocky places although it has been reported in terrestrial habitats. It has also been found in peridomestic ecotopes and might also get into houses. This species usually feeds on human blood. Although M. spinolai is the primary vector of transmission, T. infestans is the most effective vector. There are however key differences in the behavior of these two species. The alimentary profile of these two species is another point of difference between the two main vectors which transmit Chagas disease. M. spinolai bites in a shorter time compared to T. infestans. On the other hand, T. infestans bites for a longer duration, and even the defecation does not del ay. T. infestans is found in several habitats such as sylvatic environments and rock piles (1). These are the environments associated with endemic terrestrial. T. infestans is occasionally found in human habitats. The dominant vector for the transmission of Chagas disease is T. cruzi. This vector is important in the transmission of the disease to humans. However, other methods of transmission have been identified. Congenital transmission and blood transfusion are some of the most significant means of transmission (2). Other routes of transmission such oral transmission have been characterized. Due to these transmission methods, most control methods have failed. Studies suggest the characterization of the dynamics of the T. cruzi to understand the efficacy of the control mechanisms (3). infestans is intently linked to peridomestic as well as domestic structures. This species is successful because of its capacity to utilize the accessible materials in human surroundings effectively. The distribution of the species can be explained by the variation in environmental resources. The existence of T. infestans in multiple environments other than human dwellings indicates that there are sufficient resources for the vector to survive (1). In most cases, the growth of the vector is influenced by temperature even though the climate is not the sole factor that affects its population. In Chile, Chagas disease is very prevalent in the northern area. The incidence of Chagas disease in Chile is 3 to 11 per 100000 citizens while the mortality rate is 0.3 t0 0.4 per 100000 individuals (4). This prevalence insinuates that most inhabitants are still affected by the disease. Nevertheless, in 1999 the country was pronounced free of T. cruzi the vector that transmits Chagas disease (5). The introduction of control initiatives has led to the reduction of the vector in Chile. Global burden of disease Currently, approximately 5 to 18 million individuals are infected by the Chagas disease. About 10,000 people die each year as a result of the Chagas disease. The burden of the disease is even expected to increase significantly in next decade. It is even estimated that 20 to 30 percent of patients will face severe heart Chagas disease in the next decade (6). Chagas disease is also prevalent in Australia. In 2011, there were about 1928 infections in the country, which insinuates that Chagas disease is becoming a burden in Australia (7). Approximately, 300,000 individuals who have been infected with the Chagas disease live in the U.S. The rate of transmission of T. cruzi in the U.S. is however unknown. The prevalence of chagasic heart infection in the U.S. has also not been characterized (8). The vector has been found to be endemic in America. Chagas disease is a significant burden in Brazil. Recent studies show that the mortality rate linked to the disease is decreasing at a slow rate. The death rate associated with Chagas disease decreased from 3.4 percent in 2000 to 2.3 percent in 2010. This study indicates that 85.9 percent of the deaths occurred in men aged over 60 years. Most of these deaths occurred due to cardiac involvement (9). Chagas disease is a major burden to various parts of the world. Latin America specifically experiences a significant disease burden. In the past few years, the burden of Chagas disease in U.S., Pacific region, and Europe has been increasing substantial (10). The individuals who are infected with T. Cruzi in these regions might develop various conditions such as digestive tract infections or fatal cardiomyopathy. One study found that Latin American migrants have higher chances of being infected by the Chagas disease. In Latin America, there are endemic and non-endemic settings. The international economic burden of Chagas is high. Huge resources are used in the management of the Chagas disease. One study used Markov model to determine the economic burden of Chagas disease. It was found that infected persons spend about $474 to manage their condition annually. The lifetime expenditure on the management of the Chagas disease is $3456. About 10 percent of the total expenditure in the management of Chagas disease originates in Canada and the U.S. alone (11). Principles of prevention and control There are three principles for preventing and controlling the Chagas disease. The first principle is inhibiting the transmission of the disease. Transmission of the Chagas disease is interrupted by eradicating domestic vectors. The second principle is screening donated blood to minimize the chances of infecting another patient. The final principle is promoting maternal screening for infections. Newborns who test positive for the Chagas disease are exposed to treatments where needed (12). Eco-bio-social interventions have been applied in the control of T. Cruz in Chile, Mexico, Guatemala, and Bolivia. Plastering of mud houses and improved hygiene helped to reduce the infestation of Triatoma infestations in Bolivia. Window screens were used to minimize the infestation of the vector in Mexico. Another effective control and prevention principle is blanket insecticide spraying. This kind of control program has proved successful in Cochabamba (13). Since the Chagas disease is increasingly becoming a public health problem, more diagnostic tools, as well as surveillance programs, will be developed. 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