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Detection of Dengue Virus RNA in Blood Donors from Honduras and Brazil with a Prototype Transcription-Mediated Amplification Assay. Dengue. Over 2.5 billion people live in risk areas for dengue infection
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Detection of Dengue Virus RNA in Blood Donors from Honduras and Brazil with a Prototype Transcription-Mediated Amplification Assay
Dengue • Over 2.5 billion people live in risk areas for dengue infection • WHO estimates that in 2004 there were 50-100 million cases of DF, 500,000 cases of dengue hemorrhagic shock syndrome (DHS) and 20,000 consequent deaths • Epidemic is expanding due to global warming, expanding vectors and trafficking of subtypes • Dengue the most important arboviral disease of humans
Number of dengue fever cases reported per month, Brazil. A) 1986–1993, B) 1994–2003. Dark bars represent January.
Curvas epidémicas del 2002, 2003,2004 Y 2005* Casos Sospechosos de Dengue Clásico Honduras , *Semana 41 2002 (32,269 casos) 2003 (16,559 casos) 2004 (19,971 casos) 2005 (16,037 casos)* * AÑO EPIDÉMICO 1995 EXCLUÍDO FUENTE: Telegrama Epidemiológico.
Analytical sensitivity of the prototype dengue TMA assay • DEN 1, 2, 3 and 4 diluted to 1 PFU/mL
Sources of Donor Plasma from Dengue Endemic Regions 12 IR, 9 RR 11 confirmed 8 IR, 3 IR confirmation pending in progress
Planned studies of TT-Dengue • Transmission study in Honduras with BSF and Gen-Probe funding • Transmission study in Brazil under REDS-II funding • Collaborations with Australia, Hong Kong and Singapore blood banks
Dengue Transmission Study Approach • It is mandatory in Brazil to save donor serum samples for 6 months after the transfusion • Phase 1: Prevalence Study • Dengue TMA on 10,000 unlinked donor samples to determine prevalence • Phase 2: Transmission Study • collect recipient samples ~1 week after transfusion. • capture donor samples in routine repository. • Dengue TMA on both samples. • sequence virus to confirm linkage
Acknowledgements J Linnen, A Broulik, C Collins, DP Kolk, C Giachetti, L Mimms Gen-Probe Incorporated, San Diego, CA; E Vinelli Honduran Red Cross, Tegucigalpa, Honduras; E Sabino, Blood Center of Sao Paulo, Sao Paulo, Brazil; R Lanciotti, CDC, Fort Collins, CO; C Hyland, Australian Red Cross, Brisbane, Australia; L Tobler, MP BuschBlood Systems Research Institute, San Francisco, CA;