Surveillance for Zika, chikungunya and dengue virus incidence and RNAemia in blood donors at four Brazilian blood centers during 2016-2019

J Infect Dis. 2022 Jun 11;jiac173. doi: 10.1093/infdis/jiac173. Online ahead of print.


Background: Except for public health case reports, the incidence of Zika virus (ZIKV), chikungunya virus (CHIKV) and dengue virus (DENV) infection are not available to assess the potential blood transfusion safety threat in Brazil.

Methods: Pools of 6 donation samples (MP6) left over from HIV, HBV, and HCV nucleic acid testing were combined to create MP18 pools (3 MP6 pools). Samples were tested using the Grifols triplex ZIKV, CHIKV and DENV real-time transcription mediated amplification assay to estimate prevalence of RNAemia, incidence, and to compare these results to case reports in São Paulo, Belo Horizonte, Recife and Rio de Janeiro, from April 2016 - June 2019.

Results: ZIKV, CHIKV and DENV RNAemia were found from donors who donated without overt symptoms of infection that would have led to deferral. The highest RNAemic donation prevalence was (1.2%, 95% CI 0.8-1.9) for DENV in Belo Horizonte in May 2019. Arbovirus infections varied by location, time of year, and were not always aligned with annual arbovirus outbreak seasons in different regions of the country.

Conclusions: Testing donations for arboviruses in Brazil can contribute to public health. Transfusion recipients were likely exposed to ZIKV, CHIKV, DENV viremic blood components during the study period.

Keywords: Zika virus; arboviruses; blood donors; chikungunya virus; dengue virus; nucleic acid testing (NAT); transfusion medicine.