Characterization of Phietavirus Henu 2 in the virome of individuals with acute gastroenteritis.

There is a growing interest in phages as potential biotechnological tools in human health owing to the antibacterial activity of these viruses. In this study, we characterized a new member (named PhiV_005_BRA/2016) of the recently identified phage species Phietavirus Henu 2. PhiV_005_BRA/2016 was detected through metagenomic analysis of stool samples of individuals with acute gastroenteritis. PhiV_005_BRA/2016 contains double-stranded linear DNA (dsDNA), it has a genome of 43,513 base pairs (bp), with a high identity score (99%) with phage of the genus Phietavirus, species of Phietavirus Henu 2. Life style prediction indicated that PhiV_005_BRA/2016 is a lysogenic phage whose the main host is methicillin-resistant Staphylococcus aureus (MRSA). Indeed, we found PhiV_005_BRA/2016 partially integrated in the genome of distinct MRSA strains. Our findings highlights the importance of large-scale screening of bacteriophages to better understand the emergence of multi-drug resistant bacterial.

Chikungunya Virus Asian Lineage Infection in the Amazon Region Is Maintained by Asiatic and Caribbean-Introduced Variants.

The simultaneous transmission of two lineages of the chikungunya virus (CHIKV) was discovered after the pathogen's initial arrival in Brazil. In Oiapoque (Amapá state, north Brazil), the Asian lineage (CHIKV-Asian) was discovered, while in Bahia state, the East-Central-South-African lineage (CHIKV-ECSA) was discovered (northeast Brazil). Since then, the CHIKV-Asian lineage has been restricted to the Amazon region (mostly in the state of Amapá), whereas the ECSA lineage has expanded across the country. Despite the fact that the Asian lineage was already present in the Amazon region, the ECSA lineage brought from the northeast caused a large outbreak in the Amazonian state of Roraima (north Brazil) in 2017. Here, CHIKV spread in the Amazon region was studied by a Zika-Dengue-Chikungunya PCR assay in 824 serum samples collected between 2013 and 2016 from individuals with symptoms of viral infection in the Amapá state. We found 11 samples positive for CHIKV-Asian, and, from these samples, we were able to retrieve 10 full-length viral genomes. A comprehensive phylogenetic study revealed that nine CHIKV sequences came from a local transmission cluster related to Caribbean strains, whereas one sequence was related to sequences from the Philippines. These findings imply that CHIKV spread in different ways in Roraima and Amapá, despite the fact that both states had similar climatic circumstances and mosquito vector frequencies.

Composition of Eukaryotic Viruses and Bacteriophages in Individuals with Acute Gastroenteritis.

Metagenomics based on the next-generation sequencing (NGS) technique is a target-independent assay that enables the simultaneous detection and genomic characterization of all viruses present in a sample. There is a limited amount of data about the virome of individuals with gastroenteritis (GI). In this study, the enteric virome of 250 individuals (92% were children under 5 years old) with GI living in the northeastern and northern regions of Brazil was characterized. Fecal samples were subjected to NGS, and the metagenomic analysis of virus-like particles (VLPs) identified 11 viral DNA families and 12 viral RNA families. As expected, the highest percentage of viral sequences detected were those commonly associated with GI, including rotavirus, adenovirus, norovirus (94.8%, 82% and 71.2%, respectively). The most common co-occurrences, in a single individual, were the combinations of rotavirus-adenovirus, rotavirus-norovirus, and norovirus-adenovirus (78%, 69%, and 62%, respectively). In the same way, common fecal-emerging human viruses were also detected, such as parechovirus, bocaporvirus, cosavirus, picobirnavirus, cardiovirus, salivirus, and Aichivirus. In addition, viruses that infect plants, nematodes, fungi, protists, animals, and arthropods could be identified. A large number of unclassified viral contigs were also identified. We show that the metagenomics approach is a powerful and promising tool for the detection and characterization of different viruses in clinical GI samples.

High Heterogeneity of Echoviruses in Brazilian Children with Acute Gastroenteritis.

Echoviruses (E) are a diverse group of viruses responsible for various pathological conditions in humans including aseptic meningitis, myocarditis, and acute flaccid paralysis. The detection and identification of echovirus genotypes in clinical samples is challenging due to its high genetic diversity. Here, we report the complete genome sequences of nine echoviruses, obtained by next-generation sequencing of 238 fecal samples from individuals with gastroenteritis in regions of Brazil. Detected viruses were classified into six genotypes: Three E1 sequences (BRA/TO-028, BRA/TO-069 and BRA/TO-236), one E3 (BRA/TO-018), one E11 (BRA/TO-086), one E20 (BRA/TO-016), two E29 (BRA/TO-030 and BRA/TO-193), and one E30 sequence (BRA/TO-032). Phylogenetic analysis indicated that the echoviruses E1 and E29 circulating in Brazil are divergent from strains circulating worldwide. The genotype diversity identified in our study may under-represent the total echovirus diversity in Brazil because of the small sample size and the restricted geographical distribution covered by the survey.