RESUMO
BACKGROUND The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has become a major concern contributing to increased morbidity and mortality worldwide. OBJECTIVES Here we describe the replacement of the Gamma variant of concern (VOC) with Delta in the western Brazilian Amazon. METHODS In this study, we analysed 540 SARS-CoV-2 positive samples determined by qualitative real-time RT-PCR selected in the state of Rondônia between June and December 2021. The positive cohort was sequenced through next-generation sequencing (NGS) and each sample was quantified using real-time RT-qPCR, the whole genome sequence was obtained, SARS-CoV-2 lineages were classified using the system Pango and the maximum likelihood (ML) method was used to conduct phylogenetic analyses. FINDINGS A total of 540 high-quality genomes were obtained, where the Delta VOC showed the highest prevalence making up 72%, with strain AY.43 being the most abundant, while the Gamma VOC was present in 28%, where the P.1 strain was the most frequent. In this study population, only 32.96% (178/540) had completed the vaccination schedule. MAIN CONCLUSIONS This study highlighted the presence of Gamma and Delta variants of SARS-CoV-2 in RO. Furthermore, we observed the replacement of the Gamma VOC with the Delta VOC and its lineages.
RESUMO
Abstract Hepatitis B is considered an important public health problem worldwide because it is a chronic infection with a risk factor for cirrhosis and cellular hepatocellular carcinoma. In Brazil, the Rondônia State ranks first in the Northern region regarding the number of deaths due to hepatitis B. In the Amazon basin, genotype F is considered specific to the Americas identified in native populations. But few data on HBV genotyping and phylogenetic analysis are available. The objective of this study was to evaluate the genotypes and subgenotypes of the hepatitis B virus in indigenous people chronic carriers residing in cities of Guajará Mirim and Nova Mamoré in state of Rondônia/Brazil, on the border with Bolivia. A fragment of 417 bp (S gene) was amplified by PCR and submitted to nucleotide sequencing. The genotypes and subgenotypes of the HBV strains were determined through phylogenetic inference using genomic sequences from 197 representatives of the genotypes (A-H). Of the 41 chronic hepatitis B patients enrolled in this study, 27 were HBV-DNA positive. Of the 27 DNA-HBV positives, 39% (17/41) had individual HBV infection and 27% (10/41) were coinfected with HDV. The frequency of genotypes was 40.7% (11/27) for genotype D (HBV-D), 33.3% (9/27) for genotype F (HBV-F) and 25.9% (7/27) for genotype A (HBV-A) with circulating subgenotypes F2, F4, D2, D3, A1, and A2. We characterized the genotypes and subgenotypes of HBV circulating among in indigenous in the State of Rondônia shows for the first time the HBV/D genotype whit greater frequency circulating in nativos of state Rondônia. In conclusion, our findings showed a diversity of HBV genotypes, which is also found in other Brazilian geographical regions.