Blood discard rate and the prevalence of infectious and contagious diseases in blood donors from provincial towns of the state of Parana, Brazil

Background: So that an improvement in the selection of donors can be achieved and the risk to the recipient of transfused blood can be reduced, prospective donors are submitted to clinical and serological screening. Objective: This study investigated the blood discard rate and the rate of infectious and contagious diseases in blood donors from provincial towns of the state of Paraná, Brazil. Methods: This study was an exploratory cross-sectional descriptive investigation with a quantitative approach of donations between January and December 2011. Results: In the study period the Regional Blood center in Maringá, Brazil received 8337 blood donations from people living in the city and neighboring towns. However, 278 (3.33%) donations were discarded during serological screening owing to one or more positive serological markers. A total of 46.4% of the discarded blood units were confirmed positive by serology with anti-HBc being the most common (66.7%), followed by syphilis (22.5%), HBsAg (4.7%), anti-hepatitis C virus (3.1%), human immunodeficiency virus (1.5%) and Chagas' disease (1.5%). The rate of infectious-contagious diseases that can be transmitted by blood transfusions was 1.55% (129/8337) of the donor population with a frequency of 1.03% for anti-HBc and 0.35% for syphilis. Conclusion: This study demonstrates a high prevalence of the anti-HBc marker in prospective blood donors from provincial towns in the state of Paraná, Brazil