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A Moncayo

Publications and source records attributed to A Moncayo.

10 recordsLinked to original sources
PubMed2006

An update on Chagas disease (human American trypanosomiasis).

Human American trypanosomiasis or Chagas disease -- named after Carlos Chagas who first described it in 1909 -- exists only on the American continent. It is caused by a parasite, Trypanosoma cruzi, that is transmitted to humans by blood-sucking triatomine bugs, by blood transfusion, and transplacentally. Chagas disease has two, successive phases: acute and chronic. The acute phase lasts 6-8 weeks. After several years of starting the chronic phase, 20%-35% of infected individuals (the percentage varying with geographical area) develop irreversible lesions of the autonomous nervous system in the heart, the oesophagus, the colon and/or the peripheral nervous system. Data on the prevalence and distribution of Chagas disease markedly improved in quality during the 1980s, as a result of demographically representative, cross-sectional studies carried out in countries where no accurate information on these parameters was available. Experts had previously met in Brasilia, in 1979, and devised standard protocols for carrying out country-wide studies not only on the prevalence of human infection with T. cruzi but also on house infestation with the triatomine vectors. Thanks to a co-ordinated programme in the southernmost countries of South America (i.e.the 'Southern Cone'), transmission of T. cruzi by the vectors or blood transfusion has been successfully interrupted in Uruguay (from 1997), Chile (from 1999) and Brazil (from 2005), and the global incidence of new human infection with T. cruzi has decreased by 67%. Similar multi-country control initiatives have been launched in the Andean countries and in Central America, with the goal of interrupting all transmission of T. cruzi to humans by 2010 -- a goal set, in 1998, as a resolution of the World Health Assembly. Recent advances in basic research on T. cruzi include the genetic characterization of populations of the parasite and the sequencing of its genome.

Animals↗
PubMed1999

[Progress towards the interruption of transmission of Chagas disease in the southern countries].

The epidemiological and entomological data and the trends observed in the decreasing of the incidence of infection in young age groups indicate that only ninety years after the discovery of Chagas disease, the control of vectorial and transfusional transmission has reduced the incidence by 70% in the Southern Cone countries (Argentina, Bolivia, Brazil, Chile, Paraguay and Uruguay). This has been accomplished thanks to the political and financial engagement of the concerned governments who have invested US$340 millions since 1991 to the present. The initiatives to interrupt transmission of Chagas in the Andean countries and the Central American countries have begun their activities in 1997 and the evolution of the control operations allows to forecast the complete interruption in these areas before the year 2010 to comply with the mandate of Resolution WHA. 52.14 of the World Health Assembly in May 1998.

Chagas Disease↗
PubMed1998

Diagnostic electrocardiography in epidemiological studies of Chagas' disease: multicenter evaluation of a standardized method.

An electrocardiographic recording method with an associated reading guide, designed for epidemiological studies on Chagas' disease, was tested to assess its diagnostic reproducibility. Six cardiologists from five countries each read 100 electrocardiographic (ECG) tracings, including 30 from chronic chagasic patients, then reread them after an interval of 6 months. The readings were blind, with the tracings numbered randomly for the first reading and renumbered randomly for the second reading. The physicians, all experienced in interpreting ECGs from chagasic patients, followed printed instructions for reading the tracings. Reproducibility of the readings was evaluated using the kappa (kappa) index for concordance. The results showed a high degree of interobserver concordance with respect to the diagnosis of normal vs. abnormal tracings (kappa = 0.66; SE 0.02). While the interpretations of some categories of ECG abnormalities were highly reproducible, others, especially those having a low prevalence, showed lower levels of concordance. Intraobserver concordance was uniformly higher than interobserver concordance. The findings of this study justify the use by specialists of the recording of readings method proposed for epidemiological studies on Chagas' disease, but warrant caution in the interpretation of some categories of electrocardiographic alterations.

Argentina↗
PubMed1997

Progress towards the elimination of transmission of Chagas disease in Latin America.

From a global perspective, Chagas disease represents the third largest tropical disease burden after malaria and schistosomiasis. The estimated average annual per-capita gross domestic product in Latin America is US$2,966. The economic loss for the continent due to early mortality and disability by this disease in economically most productive young adults currently amounts to US$8,156 million which is equivalent to 2.5% of the external debt of the whole continent in 1995. In 1991, the Ministers of Health of Argentina, Bolivia, Brazil, Chile, Paraguay and Uruguay, launched the Southern Cone Initiative for elimination of transmission of Chagas disease. The progress towards elimination of vectorial and transfusional transmission of Chagas disease in Uruguay, Chile, Argentina and Brazil has been documented by reports from the national control programmes of the above countries. Current data on disinfestation of houses, coverage of screening in blood banks and serology in children and young adults indicate that the interruption of the vectorial and transfusional transmission of Chagas disease will be achieved in these countries as follows: Uruguay and Chile in 1999, Brazil and Argentina in 2003. By eliminating the transmission of Chagas disease in the above countries, the incidence of the disease in the whole of Latin America will be reduced by more than 70%.

Adolescent↗
PubMed1992

Chagas disease: epidemiology and prospects for interruption of transmission in the Americas.

American trypanosomiasis, or Chagas disease, is a parasitic disease caused by the haemoflagellate protozoa, Trypanosoma cruzi. The human infection occurs only in the Americas, where it is widely distributed in the periurban and rural areas of tropical and subtropical countries, from Mexico to Argentina and Chile. It is transmitted to man and other mammals mainly through insects, the triatomine bugs. As an enzootic disease, it extends from approximately latitude 42.5 degrees N (northern California and Maryland) to latitude 43.5 degrees S (southern Argentina and Chile). The results of several serological surveys indicate an overall prevalence of 16-18 million infected individuals. Up to 30% of those infected will develop the cardiac and/or hollow viscera irreversible lesions that characterize chronic Chagas disease. The endemic countries can be divided into four groups according to several indicators such as the number of confirmed human cases, the prevalence of seropositive tests in blood donors and population samples, the presence of infected vectors and reservoirs, and the existence or absence of coordinated actions towards the control of this disease. The domestic cycle of transmission, involving man and domestic animals such as dogs, cats, and domestic triatomine bugs, is the one that maintains the infections in the rural and periurban areas. Some triatomine species are well adapted to human dwellings where human and animal reservoirs are in intimate contact. The poor socioeconomic condition of the population and the domestic nature of the vector play crucial roles in maintaining the infection at an endemic level.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Parasitic diseases and urban development.

The distribution and epidemiology of parasitic diseases in both urban and periurban areas of endemic countries have been changing as development progresses. The following different scenarios involving Chagas disease, lymphatic filariasis, leishmaniasis and schistosomiasis are discussed: (1) infected persons entering nonendemic urban areas without vectors; (2) infected persons entering nonendemic urban areas with vectors; (3) infected persons entering endemic urban areas; (4) non-infected persons entering endemic urban areas; (5) urbanization or domestication of natural zoonotic foci; and (6) vectors entering nonendemic urban areas. Cultural and social habits from the rural areas, such as type of house construction and domestic water usage, are adopted by migrants to urban areas and increase the risk of disease transmission which adversely affects employment in urban populations. As the urban health services must deal with the rise in parasitic diseases, appropriate control strategies for the urban setting must be developed and implemented.

Animals↗