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Purpose: Aedes aegypti mosquito-borne diseases have a significant impact on public health in Brazil. In this study, we investigated the presence of the Zika virus (ZIKV) and dengue virus (DENV) in serum and urine samples from symptomatic participants who attended an Emergency Care Unit located in a city in the northwestern region of São Paulo between February 2018 and April 2019. Methods: Serum and urine samples were collected from participants suspected of having arbovirus infection. After the extraction of viral RNA, viral detection was performed by real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) (One-Step RT-qPCR). Results: A total of 305 participants participated in this study. A total of 283 blood and 270 urine samples were collected. Of 305 patients, 36.4% (111/305) were positive for ZIKV, 43.3% (132/305) for DENV2, and 0.3% (1/305) for DENV1. Coinfection with ZIKV/DENV2 was observed in 13.1% of participants. If only serum samples were used, ZIKV detection would have decreased to 23.3% (71/305). Of all the participants included in the study, only one was suspected of having ZIKV infection based on clinical diagnosis, and the remaining participants were suspected of having DENV. Conclusion: By testing serum and urine samples, we increased the detection of both viruses and detected considerable levels of ZIKV and DENV-2 coinfection when compared to other studies. Additionally, we detected an unnoticed ZIKV outbreak in the city. These findings highlight the importance of the molecular diagnosis of arboviruses to aid public health surveillance and management strategies. [ABSTRACT FROM AUTHOR]

Purpose: Studies show that around 80% of Zika virus (ZIKV) infections are asymptomatic. The present study tested urine samples from volunteers, unsuspected of arboviral infection, which attended an emergency care unit (ECU) in Mirassol, Brazil, from March 2018 to April 2019. Methods: The volunteers were divided into two groups. The first group was composed of outpatients who were not suspected to have an arbovirus infection. This first group was subdivided into two subgroups: outpatients with and without arbovirus-like symptoms. The second group consisted of companions of outpatients treated at the ECU. The second group was also subdivided into two subgroups: totally asymptomatic individuals and those who had arbovirus-like symptoms. RNA was extracted from urine samples, followed by RT-qPCR for ZIKV. Results: We found that 11% (79/697) of the samples tested positive for ZIKV-RNA. Among the ZIKV-RNA-positive individuals, 16.5% (13/79) were companions, of which 61.5% (8/13) were totally asymptomatic and 38.5% (5/13) reported symptoms that could be suggestive of arbovirus infection. In addition, 83.5% (66/79) of the ZIKV-RNA-positive individuals were outpatients without a clinical diagnosis of arbovirus. Of these undiagnosed ZIKV-RNA-positive outpatients, 47% (31/66) had no arbovirus-related symptoms. Conclusion: Our study shows the effectiveness of urine as a non-invasive sample to detect the incidence of ZIKV infection. We also highlight the importance of ZIKV molecular diagnosis to aid public health surveillance and prevention of congenital Zika syndrome and other ZIKV-associated diseases. [ABSTRACT FROM AUTHOR]

Zika virus (ZIKV) is a mosquito-transmitted Flavivirus, originally identified in Uganda in 1947 and recently associated with a large outbreak in South America. Despite extensive efforts there are currently no approved antiviral compounds for treatment of ZIKV infection. Here we describe the antiviral activity of diarylamines derived from anthranilic acid (FAMs) against ZIKV. A synthetic FAM (E3) demonstrated anti-ZIKV potential by reducing viral replication up to 86%. We analyzed the possible mechanisms of action of FAM E3 by evaluating the intercalation of this compound into the viral dsRNA and its interaction with the RNA polymerase of bacteriophage SP6. However, FAM E3 did not act by these mechanisms. In silico results predicted that FAM E3 might bind to the ZIKV NS3 helicase suggesting that this protein could be one possible target of this compound. To test this, the thermal stability and the ATPase activity of the ZIKV NS3 helicase domain (NS3Hel) were investigated in vitro and we demonstrated that FAM E3 could indeed bind to and stabilize NS3Hel. [ABSTRACT FROM AUTHOR]

In Africa, Old World Primates are involved in the maintenance of sylvatic circulation of ZIKV. However, in Brazil, the hosts for the sylvatic cycle remain unknown. We hypothesized that free-living NHPs might play a role in urban/periurban ZIKV dynamics, thus we undertook an NHP ZIKV investigation in two cities in Brazil. We identified ZIKV-positive NHPs and sequences obtained were phylogenetically related to the American lineage of ZIKV. Additionally, we inoculated four C. penicillata with ZIKV and our results demonstrated that marmosets had a sustained viremia. The natural and experimental infection of NHPs with ZIKV, support the hypothesis that NHPs may be a vertebrate host in the maintainance of ZIKV transmission/circulation in urban tropical settings. Further studies are needed to understand the role they may play in maintaining the urban cycle of the ZIKV and how they may be a conduit in establishing an enzootic transmission cycle in tropical Latin America. [ABSTRACT FROM AUTHOR]