Date Published: March 25, 2019
Publisher: Public Library of Science
Author(s): Svetoslav Nanev Slavov, Daiani Cristina Cilião-Alves, Filipe Almeida Carvalho Gonzaga, Drielly Rodrigues Moura, Ana Carolina Alves Melo de Moura, Lorena Aparecida Gonçalves de Noronha, Évelin Mota Cassemiro, Bárbara Maciel Sidou Pimentel, Fabiano José Queiroz Costa, Grasiela Araújo da Silva, Doralina do Amaral Rabello Ramos, Wildo Navegantes de Araújo, Simone Kashima, Rodrigo Haddad, Pierre Roques.
Dengue virus (DENV) transmission by blood transfusion is an important route of viral acquisition during outbreaks. The prevalence of DENV markers (viral RNA, NS1, anti-DENV IgM, and IgG) among blood donors in Central-West Brazil has never been evaluated. Our aim was to evaluate the full set of serological and molecular markers for DENV among blood donors of the Federal District of Brazil during an extensive outbreak in 2016. We found an anti-DENV IgM prevalence of 6.74% (n = 32/475). Of 475, 20 samples (4.21%) were also anti-DENV IgG positive. All samples were non-reactive for NS1 and DENV RNA. Our results imply that a significant proportion of the tested donors had experienced asymptomatic infection. More studies are necessary to evaluate the real prevalence of DENV viremia in blood donors from the Federal District of Brazil and if specific measures are needed to routinely test the blood donors for DENV RNA during outbreaks.
Dengue viruses (DENV 1–4) are etiological agents of Dengue fever, which is the most important arboviral disease in the world . DENV 1–4 are primarily transmitted by arthropod mosquito vectors of the Aedes genus (A. aegypti and A. albopictus). However, as indicated by extensive DENV outbreaks with a significant proportion of asymptomatic cases (up to 50%), this arboviral disease can also be transmitted by blood transfusion in the form of transfusion-transmitted DENV (TT-DENV) [2,3]. Transfusion-transmitted DENV cases have been documented in distinct, mainly tropical, geographic locations, including Central and South America and Southeast Asia, e.g., Brazil [3,4], Puerto Rico , Pakistan , Hong Kong , and Singapore .
Of the 475 blood samples collected, 315 (65.8%) were obtained from male blood donors (36.5 ± 10.8 years old) and 160 (34.2%) belonged to female (32.4 ± 10.2 years old) blood donors (Table 1). Considering the information in the Epidemiological Bulletin, a higher number of probable DENV cases occurred between December 2015 and May 2016 (Fig 1), peaking in February-March, which coincides with the rainy period of the study region.
Dengue fever, the most prevalent arboviral disease in Brazil, represents a major public health problem because no governmental measures are directed at controlling the frequent outbreaks in the country . DENV is of great consequence in the area of transfusion because the virus can be transmitted in blood and cause hemorrhagic outcomes in the recipients of blood components .
In conclusion, this study, which examined the prevalence of DENV IgM/anti-DENV IgG and DENV RNA in blood donors from Central-West Brazil during an outbreak in 2016, demonstrated that 6.75% of tested blood donors had experienced a recent asymptomatic DENV infection, as defined by a DENV IgM positive result, which shows that a significant portion of the population could be asymptomatic DENV carriers. Although we detected neither DENV RNA nor NS1 antigen, the observed high prevalence of anti-DENV IgM in healthy donors who reported no symptoms at the time of donation indicates possible participation of this virus in TT-DENV in the examined region.