Negeviruses isolated from mosquitoes in the Brazilian Amazon.

BACKGROUND: There are several groups of viruses including Insect Specific Viruses (ISV) such as the taxon Negevirus, a group of viruses phylogenetically related to plant viruses. Negeviruses replicate in mosquito cells, but not in vertebrate cells. METHODS: Pools of hematophagous arthropods were inoculated in Vero and C6/36 cells. The cells were observed to detect possible cytopathic effect. Then, indirect immunofluorescence, RT-PCR, and nucleotide sequencing were performed. RESULTS: Seven samples which presented negative results for flaviviruses, alphaviruses and bunyaviruses, but showed cytopathic effect in C6/36 cells were sequenced. We identified the occurrence of a variety of ISVs, most of them belonging to the taxon Negevirus: The Brejeira, Negev, Cordoba and Wallerfield viruses, including a new virus for science, tentatively named Feitosa virus. CONCLUSIONS: We detected negeviruses in the Amazon region, including two viruses that were isolated for the first time in Brazil: Cordoba virus and the Negev virus and, a new virus for science: the Feitosa virus.

Isolation and sequencing of Orthoflavivirus ilheusense from mosquitoes collected in the Brazilian cerrado, West-Central region, Brazil.

The Orthoflavivirus ilheusense (ILHV) is an arbovirus that was first isolated in Brazil in 1944 during an epidemiologic investigation of yellow fever. Is a member of the Flaviviridae family and it belongs to the antigenic complex of the Ntaya virus group. Psorophora ferox is the primary vector of ILHV and this study presents the isolation and phylogenetic analysis of ILHV in a pool of Ps. ferox collected in the state of Goiás in 2021. Viral isolation tests were performed on Vero cells and C6/36 clones. The indirect immunofluorescence test (IFI) was used to confirm the positivity of the sample. The positive sample underwent RT-qPCR, sequencing, and phylogenetic analysis. This is the first report of ILHV circulation in this municipality and presented close relationship between this isolate and another ILHV isolate collected in the city of Belém (PA).

Description of mitochon genome and phylogenetic considerations of Sabethes bipartipes, Sabethes cyaneus, Sabethes quasicyaneus, and Sabethes tarsopus (Diptera: Culicidae).

The genus Sabethes (Diptera: Culicidae) comprises species of great epidemiological relevance, particularly involved in transmission cycles of the Yellow fever virus in South America. Given the unavailability of information related to aspects of evolutionary biology and molecular taxonomy of species of this genus of mosquitoes, we report here the first sequencing of the mitochondrial genomes of Sabethes bipartipes, Sabethes cyaneus, Sabethes tarsopus, and Sabethes quasicyaneus. The sequences obtained showed an average length of 14,920 bp, comprising 37 functional genes (13 PCGs, 22 tRNA, and 02 rRNA). The phylogenies reconstructed by Maximum likelihood and Bayesian inference methods, based on the concatenated sequences of all 13 PCGs, produced similar topologies and strongly supported the monophyletic relationship between the Sabethes subgenera, corroborating the known taxonomic classification based on aspects of the external morphology of the taxa assessed. The data and information produced from the Sabethes species evaluated here may be useful for future taxonomic and evolutionary studies of the genus, as well as the Culicidae family.

Description of the mitogenome and phylogeny of Aedes spp. (Diptera: Culicidae) from the Amazon region.

The genus Aedes (Diptera: Culicidae) includes species of great epidemiological relevance, particularly involved in transmission cycles of leading arboviruses in the Brazilian Amazon region, such as the Zika virus (ZIKV), Dengue virus (DENV), Yellow fever virus (YFV), and Chikungunya virus (CHIKV). We report here the first putatively complete sequencing of the mitochondrial genomes of Brazilian populations of the species Aedes albopictus, Aedes scapularis and Aedes serratus. The sequences obtained showed an average length of 14,947 bp, comprising 37 functional subunits, typical in animal mitochondria (13 PCGs, 22 tRNA, and 2 rRNA). The phylogeny reconstructed by Maximum likelihood method, based on the concatenated sequences of all 13 PCGs produced at least two non-directly related groupings, composed of representatives of the subgenus Ochlerotatus and Stegomyia of the genus Aedes. The data and information produced here may be useful for future taxonomic and evolutionary studies of the genus Aedes, as well as the Culicidae family.

Arboviruses in Free-Ranging Birds and Hematophagous Arthropods (Diptera, Nematocera) from Forest Remnants and Urbanized Areas of an Environmental Protection Area in the Amazon Biome.

The rapid and disorderly urbanization in the Amazon has resulted in the insertion of forest fragments into cities, causing the circulation of arboviruses, which can involve hematophagous arthropods and free-ranging birds in the transmission cycles in urban environments. This study aimed to evaluate the circulation of arboviruses in free-ranging birds and hematophagous arthropods captured in an Environmental Protection Area in the Belem metropolitan area, Brazil. Birds were captured using mist nets, and hematophagous arthropods were collected using a human protected attraction technique and light traps. The birds' sera were subjected to a hemagglutination inhibition test to detect antibodies against 29 arbovirus antigens. Arthropod macerates were inoculated into C6/36 and VERO cell cultures to attempt viral isolation and were tested using indirect immunofluorescence, subsequent genetic sequencing and submitted for phylogenetic analysis. Four bird sera were positive for arbovirus, and one batch of Psorophora ferox was positive for Flavivirus on viral isolation and indirect immunofluorescence. In addition, the Ilheus virus was detected in the sequencing and phylogenetic analysis. The presence of antibodies in sera from free-ranging birds and the isolation of Ilheus virus in Psorophora ferox indicate the circulation of arboviruses in forest remnants in the urban center of Belem.