Pathogens
December 2024
During the COVID-19 pandemic, SARS-CoV-2 caused an alarming number of cases and deaths worldwide. Brazil was severely affected from late 2020 onward, especially after the emergence of variants of concern (VOCs) and variants of interest (VOIs). Although much is known about the dynamics and evolution of SARS-CoV-2 VOIs and VOCs in the country, information is still lacking on how the cocirculation of several SARS-CoV-2 lineages, along with the lack of vaccination and low adherence to social isolation measures, shaped the first year of the COVID-19 pandemic in Brazil.
View Article and Find Full Text PDFBackground: Brazil is considered an epicenter for emerging and re-emerging arboviruses that significantly impact public health. The mid-sized city of São José do Rio Preto (SJdRP) in northwestern São Paulo state is considered hyperendemic for arboviral diseases, with case numbers climbing each year. Only 45 cases of chikungunya (CHIKV) were reported in the city from 2015 to 2022, indicating cryptic circulation of this virus, but cases in the state increased notably in 2023.
View Article and Find Full Text PDFThe high transmissibility, rapid evolution, and immune escape of SARS-CoV-2 variants can influence the course of infection and, in turn, morbidity and mortality in COVID-19, posing a challenge in controlling transmission rates and contributing to the emergence and spread of new variants. Understanding the factors that shape viral genetic variation is essential for comprehending the evolution and transmission of SARS-CoV-2, especially in vaccinated individuals where immune response plays a role in the progression and spread of this disease. In this context, we evaluated the impact of immunity induced by the CoronaVac vaccine (Butantan/Sinovac) on intra-host genetic diversity, analyzing 118 whole-genome sequences of SARS-CoV-2 from unvaccinated and vaccinated patients infected with the Gamma variant.
View Article and Find Full Text PDFSince 2021, the emergence of variants of concern (VOC) has led Brazil to experience record numbers of in COVID-19 cases and deaths. The expanded spread of the SARS-CoV-2 combined with a low vaccination rate has contributed to the emergence of new mutations that may enhance viral fitness, leading to the persistence of the disease. Due to limitations in the real-time genomic monitoring of new variants in some Brazilian states, we aimed to investigate whether genomic surveillance, coupled with epidemiological data and SARS-CoV-2 variants spatiotemporal spread in a smaller region, can reflect the pandemic progression at a national level.
View Article and Find Full Text PDFLower respiratory tract infections (LRIs) are a significant cause of disability-adjusted life-years (DALYs) across all age groups, especially in children under 9 years of age, and adults over 75. The main causative agents are viruses, such as influenza and respiratory syncytial virus (RSV). Viral LRIs in adults have historically received less attention.
View Article and Find Full Text PDFAcute respiratory infections are a constant public health problem causing childhood morbidity and mortality worldwide. Reported cases of major respiratory infections decreased in 2020 after restrictive measures were adopted to contain the COVID-19 pandemic, but there is little data on the impact after these measures were relaxed in the subsequent years. This study conducted molecular analysis to identify rhinovirus, respiratory syncytial virus, influenza A virus, and adenovirus in SARS-CoV-2-negative samples taken from symptomatic pediatric patients during 2021 and 2022 to ascertain the impact of pandemic response measures within the broader epidemiological scenario.
View Article and Find Full Text PDFThe genetic diversity of the dengue virus is characterized by four circulating serotypes, several genotypes, and an increasing number of existing lineages that may have differences in the potential to cause epidemics and disease severity. Accurate identification of the genetic variability of the virus is essential to identify lineages responsible for an epidemic and understanding the processes of virus spread and virulence. Here, we characterize, using portable nanopore genomic sequencing, different lineages of dengue virus 2 (DENV-2) detected in 22 serum samples from patients with and without dengue warning signs attended at Hospital de Base of São José do Rio Preto (SJRP) in 2019, during a DENV-2 outbreak.
View Article and Find Full Text PDFSão Paulo is the financial center of Brazil, with a population of over 12 million, that receives travelers from all over the world for business and tourism. It was the first city in Brazil to report a case of COVID-19 that rapidly spread across the city despite the implementation of the restriction measures. Despite many reports, much is still unknown regarding the genomic diversity and transmission dynamics of this virus in the city of São Paulo.
View Article and Find Full Text PDFViruses
September 2022
Our effort in SARS-CoV-2 genomic surveillance in Brazil has detected the Alpha Variant of Concern with a predominance higher than 75% in the population of Ilhabela island (São Paulo State) at a time when the Gamma VOC was already predominating the mainland raised concerns for closer surveillance on this island. Therefore, we intensified the surveillance for 24 weeks by generating data from 34% of local positive cases. Our data show that the patterns of VOC predominance dynamics and infection rates were in general distinct from the mainland.
View Article and Find Full Text PDFBackground: The emergence of the Brazilian variant of concern, Gamma lineage (P.1), impacted the epidemiological profile of COVID-19 cases due to its higher transmissibility rate and immune evasion ability.
Methods: We sequenced 305 SARS-CoV-2 whole-genomes and performed phylogenetic analyses to identify introduction events and the circulating lineages.
Delta VOC is highly diverse with more than 120 sublineages already described as of November 30, 2021. In this study, through active monitoring of circulating severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants in the state of São Paulo, southeast Brazil, we identified two emerging sublineages from the ancestral AY.43 strain which were classified as AY.
View Article and Find Full Text PDFViruses
December 2021
The current COVID-19 pandemic demands massive testing by Real-time RT-PCR (Reverse Transcription Polymerase Chain Reaction), which is considered the gold standard diagnostic test for the detection of the SARS-CoV-2 virus. However, the virus continues to evolve with mutations that lead to phenotypic alterations as higher transmissibility, pathogenicity or vaccine evasion. Another big issue are mutations in the annealing sites of primers and probes of RT-PCR diagnostic kits leading to false-negative results.
View Article and Find Full Text PDFInterspecific hybridization may lead to sterility and/or inviability through differential expression of genes and transposable elements (TEs). In , studies have reported massive TE mobilization in hybrids from interspecific crosses of species presenting high divergence times. However, few studies have examined the consequences of TE mobilization upon hybridization in recently diverged species, such as and We have sequenced transcriptomes of and the subspecies and their reciprocal hybrids, as well as piRNAs, to analyze the impact of genomic stress on TE regulation.
View Article and Find Full Text PDFThe Lambda variants of interest (VOI) (C37/GR/452Q.V1/21G) was initially reported in Lima, Peru but has gained rapid dissemination through other Latin American countries. Nevertheless, the dissemination and molecular epidemiology of the Lambda VOI in Brazil is unknown apart from a single case report.
View Article and Find Full Text PDFThe rapid development of efficacious and safe vaccines against coronavirus disease 2019 (COVID-19) has been instrumental in mitigating the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Moreover, the emergence of SARS-CoV-2 variants raised concerns on the efficacy of these vaccines. Herein, we report two cases of breakthrough infections with the P1 variant in patients vaccinated with CoronaVac, which is one of the two vaccines authorized for emergency use in the Brazilian immunization program.
View Article and Find Full Text PDFInterspecific hybridization is a stressful condition that can lead to sterility and/or inviability through improper gene regulation in Drosophila species with a high divergence time. However, the extent of these abnormalities in hybrids of recently diverging species is not well known. Some studies have shown that in Drosophila, the mechanisms of postzygotic isolation may evolve more rapidly in males than in females and that the degree of viability and sterility is associated with the genetic distance between species.
View Article and Find Full Text PDFVariation in the size and morphological differences intraspecific of Nesotriatoma flavida led to the description of N. bruneri. However, two years later the same author proposed the synonymization N.
View Article and Find Full Text PDFThe brasiliensis complex is composed of five triatomine species, and different approaches suggest that Triatoma lenti and Triatoma petrochiae may be the new members. Therefore, this study sought to analyze the phylogenetic relationships within this complex by means of the D2 region of the 28S RNA gene, and to analyze the degree of polymorphism and phylogenetic significance of this gene for South American triatomines. Phylogenetic analysis by using sequence fragments of the D2 domain did not allow to perform phylogenetic inferences on species within the brasiliensis complex, because the gene alignment composed of a matrix with 37 specimens exhibited only two variable sites along the 567 base pairs used.
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