Dengue Virus Ribonucleic Acid Detection Rates in Blood Donors Correlate With Local Infection Incidences During a Dengue Outbreak in Taiwan

Abstract

Abstract Background Evidence for mitigation of transfusion-transmitted dengue informed by surveillance data is lacking. In this study, we evaluated the risk of positive dengue viral (DENV) ribonucleic acid (RNA) from blood transfusions during a large outbreak in Taiwan. Methods Serum collected from blood donors living in districts experiencing the dengue epidemic were tested for DENV RNA using a qualitative transcription-mediated nucleic acid amplification assay (TMA). The TMA-reactive specimens were further tested for immunoglobulin (Ig)M and IgG antibodies, nonstructural protein 1 (NS1) antigen, and viral RNA by reverse-transcription polymerase chain reaction. We estimated DENV RNA prevalence and the number of DENV infections among blood donors. Results A total of 4976 specimens were tested for DENV RNA, and 21 were TMA-reactive. The detection rate was 0.84 (95% confidence interval [CI], 0.15–4.73), 3.36 (95% CI, 1.31–8.60), and 6.19 (95% CI, 3.14–12.17) per 1000 donors in districts where the weekly dengue incidence was 5–50, 50–200, and 200 or more per 100 000 residents, respectively. Alanine aminotransferase screening only detected 4.4% of TMA-reactive donations. A total of 143 transfusion-transmitted DENV infections probably occurred during this outbreak, accounting for 9.2 in 10 000 dengue infections. Conclusions Approximately 0.5%–1% of blood donations were DENV RNA positive in epidemic districts. The correlation of DENV RNA rates with dengue incidence may inform the design of effective control measures.