Keywords
Chagas disease; T. cruzi; Transfusional transmission
Abstract
Chagas Disease (CD), caused by Trypanosoma cruzi, is a medical and social problem of great importance in Brazil and a serious public health problem in Latin America. The World Health Organization estimates that the T. cruzi infection affects about 7 million of people in 15 countries, with an annual incidence of 200,000 cases. In this context, is worth mentioning the main forms of transmission of CD: contaminated excreta of vector (triatomine) at the moment of the blood repast and secondary transmission routes as: Oral intake of food contaminated with triatomine excreta infected, labs accident and blood transfusion. The last one, was a reason of disease transmission to many people until it was discovered that the parasite could be found in the bloodstream of the individual with the disease and during blood transfusion, these infecting forms would be transferred to the blood receiver of a contaminated individual that can be symptomatic or asymptomatic. Evaluating the methods available for the diagnosis of CD, serological tests are methods of choice in clinical laboratories and blood banks, because they have the highest sensitivity coefficients, which allow avoiding with greater reliability the transmission by blood transfusion. However, for the serological control of CD on blood banks, it is necessary to seek tests that show 100% of sensitivity and specificity to protect the blood transfusion receivers, furthermore to identifying a donor as a CD holder, ruling out cases of false positive. Nowadays, the serological diagnosis of Chagas’ infection still presents some limitations such as the presence of inconclusive and false-positive results (due to cross-reactions with other parasitic diseases). This is a big concern of blood banks throughout the country, because the tests used today have a great sensitivity, however may erroneously exclude some blood donors able. After some years of discovery of this type of transmission, this subject is considered a public health problem nowadays due to the fact to cause great damage by the discard of supposedly contaminated blood bags; as well causing psychic problems for volunteers who believe have a serious and no cure illness.
Citation
Miguel CB, Mendes NS, Costa TA, Agostinho F, Machado FB, Paulino TP, et al. Chagas Disease and Transfusion Transmission: A Review. SM Trop Med J. 2017; 2(1): 1012.