Co-infecção pelo vírus dengue 3 e 4 em pacientes da Amazônia brasileira

The natural co-infection with dengue virus can occur in highly endemic areas where different serotypes have been observed for many years. We report here four cases of DENV-3/DENV-4 co-infection detected by serological and molecular tests among 674 patients with acute undifferentiated fever from the tropical medicine reference center of Manaus City, Brazil, between 2005 and 2010. Analysis of the sequences obtained indicated the presence of genotype 3 and 1 for DENV-3 and DENV-4 respectively.A co-infecção natural com os vírus dengue pode ocorre em áreas altamente endêmicas onde diferentes sorotipos têm sido transmitidos por muitos anos. Relatamos aqui quatro casos de co-infecção com DENV-3/DENV-4 detectados por testes sorológicos e moleculares entre 674 pacientes com febre indiferenciada aguda, atendidos em um centro de medicina tropical de referência da cidade de Manaus, Brasil, entre 2005 e 2010. As análises das sequências obtidas indicaram a presença dos genotipos 3 e 1 para DENV-3 e DENV-4 respectivamente

Co-infection of Dengue virus by serotypes 3 and 4 in patients from Amazonas, Brazil

The natural co-infection with dengue virus can occur in highly endemic areas where different serotypes have been observed for many years. We report here four cases of DENV-3/DENV-4 co-infection detected by serological and molecular tests among 674 patients with acute undifferentiated fever from the tropical medicine reference center of Manaus City, Brazil, between 2005 and 2010. Analysis of the sequences obtained indicated the presence of genotype 3 and 1 for DENV-3 and DENV-4 respectively

Multiplexed reverse transcription real-time polymerase chain reaction for simultaneous detection of Mayaro, Oropouche, and Oropouche-like viruses

Submitted by Raphael Rodrigues ([email protected]) on 2017-06-13T14:33:21Z No. of bitstreams: 1 ve_Felipe_Gomes_Naveca_etal_ILMD_2017.pdf: 611276 bytes, checksum: 7e501740aec08f9832c2d20d41b9f4a9 (MD5)Approved for entry into archive by Raphael Rodrigues ([email protected]) on 2017-06-13T14:42:56Z (GMT) No. of bitstreams: 1 ve_Felipe_Gomes_Naveca_etal_ILMD_2017.pdf: 611276 bytes, checksum: 7e501740aec08f9832c2d20d41b9f4a9 (MD5)Made available in DSpace on 2017-06-13T14:42:56Z (GMT). No. of bitstreams: 1 ve_Felipe_Gomes_Naveca_etal_ILMD_2017.pdf: 611276 bytes, checksum: 7e501740aec08f9832c2d20d41b9f4a9 (MD5) Previous issue date: 2017Fundação Oswaldo Cruz. Instituto Leônidas e Maria Deane. Manaus, AM, Brasil.Fundação Oswaldo Cruz. Instituto Leônidas e Maria Deane. Manaus, AM, Brasil.Fundação Oswaldo Cruz. Instituto Leônidas e Maria Deane. Manaus, AM, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil / Unversidade do Estado do Pará. Belém, PA, Brasil.We describe a sensitive method for simultaneous detection of Oropouche and Oropouche-like viruses carrying the Oropouche S segment, as well as the Mayaro virus, using a multiplexed one-step reverse transcription real-time polymerase chain reaction (RT-qPCR). A chimeric plasmid containing both Mayaro and Oropouche targets was designed and evaluated for the in vitro production of transcribed RNA, which could be easily used as a non-infectious external control. To track false-negative results due to PCR inhibition or equipment malfunction, the MS2 bacteriophage was also included in the multiplex assay as an internal positive control. The specificity of the multiplex assay was evaluated by Primer-Blast analysis against the entire GenBank database, and further against a panel of 17 RNA arboviruses. The results indicated an accurate and highly sensitive assay with amplification efficiency greater than 98% for both targets, and a limit of detection between two and 20 copies per reaction. We believe that the assay described here will provide a tool for Mayaro and Oropouche virus detection, especially in areas where differential diagnosis of Dengue, Zika and Chikungunya viruses should be performed

Genomic and epidemiological surveillance of Zika virus in the Amazon region

Zika virus (ZIKV) has caused an explosive epidemic linked to severe clinical outcomes in the Americas. Until June 2018, 4,929 ZIKV suspected infections and 46 congenital syndrome cases were reported in Manaus city, Amazonas State, Brazil. Although Manaus is a key demographic hub in the Amazon region, little is known about the ZIKV epidemic there, both in terms of transmission and viral genetic diversity. Using portable virus genome sequencing we generated 59 ZIKV genomes in Manaus. Phylogenetic analyses indicated multiple introductions of ZIKV from northeast Brazil to Manaus. Spatial genomic analysis of virus movement among 6 areas in Manaus suggested that populous northern neighborhoods acted as sources of virus transmission to other neighborhoods. Our study revealed how the ZIKV epidemic was ignited and maintained within the largest urban metropolis in the Amazon. Those results might contribute to improve public health response to outbreaks in Brazil

Reduced neutralization of SARS-CoV-2 B.1.617 by vaccine and convalescent serum

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has undergone progressive change, with variants conferring advantage rapidly becoming dominant lineages, e.g., B.1.617. With apparent increased transmissibility, variant B.1.617.2 has contributed to the current wave of infection ravaging the Indian subcontinent and has been designated a variant of concern in the United Kingdom. Here we study the ability of monoclonal antibodies and convalescent and vaccine sera to neutralize B.1.617.1 and B.1.617.2, complement this with structural analyses of Fab/receptor binding domain (RBD) complexes, and map the antigenic space of current variants. Neutralization of both viruses is reduced compared with ancestral Wuhan-related strains, but there is no evidence of widespread antibody escape as seen with B.1.351. However, B.1.351 and P.1 sera showed markedly more reduction in neutralization of B.1.617.2, suggesting that individuals infected previously by these variants may be more susceptible to reinfection by B.1.617.2. This observation provides important new insights for immunization policy with future variant vaccines in non-immune populations