Dengue virus surveillance: Detection of DENV-4 in the city of São José do Rio Preto, SP, Brazil

Abstract

Dengue viruses are the most common arbovirus infection worldwide and are caused by four distinct serotypes of the dengue virus (DENV). In the present study, we assessed DENV transmission in São José do Rio Preto (SJRP) from 2010 to 2014. We analyzed blood samples from febrile patients who were attended at health care centers in SJRP. DENV detection was performed using multiplex RT-PCR, using flavivirus generic primers, based on the genes of the non-structural protein (NS5), followed by nested-PCR assay with species-specific primers. We analyzed 1549 samples, of which 1389 were positive for NS1 by rapid test. One thousand and eight-seven samples (78%) were confirmed as positive by multiplex RT-PCR: DENV-4, 48.5% (528/1087); DENV-1, 41.5% (449/1087); DENV-2, 9.5% (104/1087); and co-infection (5 DENV-1/DENV-4, 1 DENV-1/DENV-2), 0.5% (6/1087). Phylogenetic analysis of the DENV-4 grouped the isolates identified in this study with the American genotype and the showed a relationship between isolates from SJRP and isolates from the northern region of South America. Taken together, our data shows the detection and emergence of new dengue genotype in a new region and reiterate the importance of surveillance programs to detect and trace the evolution of DENV.

Evidence of natural Zika virus infection in neotropical non-human primates in Brazil

“…All ZIKV positive animals were negative for YFV in RT-qPCR and RT-nested-PCR and a subset that was tested by immunohistochemistry to YFV exposure, were also negative. Our results demonstrated that free-living marmosets and capuchin monkeys may be naturally infected with ZIKV in urban areas of Southeast Brazil (São Paulo and Minas Gerais States), regions of intense arboviral circulation 26 – 32 . A previous study demonstrated ZIKV RNA detection in sera and/or oral swabs (not further specified in prior studies) from free-living common marmosets (n = 4) and capuchin monkeys (n = 3), in Northeast Brazil 8 .…”

Using adult Aedes aegypti females to predict areas at risk for dengue transmission: A spatial case-control study

“…Our results suggest that NAF identifies areas of higher risk of dengue occurrence. Additionally, NAF may serve as a new surveillance and control tool to detect and restrain The validation of NAF as an index to measure risk of disease occurred simultaneously with the introduction of DENV-4 in São José do Rio Preto (Colombo et al, 2016;Rocco et al, 2012). DENV-4 was the only serotype detected in our mosquitoes, which is an indication this was the main serotype causing dengue fever, at least in the study area.…”

Fatal Outcome of Ilheus Virus in the Cerebrospinal Fluid of a Patient Diagnosed with Encephalitis

“…Since 2006, we have established arbovirus surveillance for encephalitis-suggestive cases in the city of São José do Rio Preto (SJdRP), State of São Paulo, Brazil, located in a hyper-endemic area for dengue virus (DENV) [ 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 ], Saint Louis encephalitis [ 40 , 41 ], Zika virus (ZIKV) [ 34 ], and documented co-infection among various flaviviruses [ 30 , 41 , 42 ]. Herein, we report a case of cerebral encephalitis in a patient infected with ILHV that was observed by our surveillance team in São José do Rio Preto (SJdRP).…”