Influenza outbreak during the surge of SARS-CoV-2 omicron in a metropolitan area from southern Brazil: genomic surveillance.

Influenza circulation was significantly affected in 2020-21 by the COVID-19 pandemic. During this time, few influenza cases were recorded. However, in the summer of 2021-22, an increase in atypical influenza cases was observed, leading to the resurgence of influenza in the southernmost state of Brazil, Rio Grande do Sul (RS). The present study aimed to identify the circulation of FLUAV, FLUBV and SARS-CoV-2 and characterize the influenza genomes in respiratory samples using high-throughput sequencing technology (HTS). Respiratory samples (n = 694) from patients in RS were selected between July 2021 and August 2022. The samples were typed using reverse transcriptase real-time PCR (RT-qPCR) and showed 32% (223/694) of the samples to be positive for SARS-CoV-2, 7% for FLUAV (H3) (49/694). FLUBV was not detected. RT-qPCR data also resulted in FLUAV and SARS-CoV-2 co-infections in 1.7% (4/223) of samples tested. Whole genome sequencing of FLUAV produced 15 complete genomes of the H3N2 subtype, phylogenetically classified in the 3C.2a1b.2a.2a.3 subclade and revealing the dominance of viruses in the southern region of Brazil. Mutation analysis identified 72 amino acid substitutions in all genes, highlighting ongoing genetic evolution with potential implications for vaccine effectiveness, viral fitness, and pathogenicity. This study underscores limitations in current surveillance systems, advocating for comprehensive data inclusion to enhance understanding of influenza epidemiology in southern Brazil. These findings contribute valuable insights to inform more effective public health responses and underscore the critical need for continuous genomic surveillance.

Exploring the Relationship Between Genetic Instability and Health Outcomes in Acute and Chronic Post-COVID Syndrome.

The COVID-19 pandemic has led to the emergence of acute and chronic post-COVID syndromes, which present diverse clinical manifestations. The underlying pathophysiology of these conditions is not yet fully understood, but genetic instability has been proposed as a potential contributing factor. This study aimed to explore the differential impact of physical and psychological health factors on genetic instability in individuals with acute and chronic post-COVID syndromes. In this study, three groups of subjects were analyzed: a control group, an acute post-COVID group, and a chronic post-COVID group, with a total of 231 participants. The participants were assessed using a questionnaire for long-COVID-19COVID, and female participants reported more symptoms than male participants in areas related to fatigue, memory, mental health, and well-being during the chronic phase. Genetic instability was assessed using the comet assay, and participants' physical and psychological profiles were evaluated. The overall results showed no significant differences in DNA damage, as measured by the comet assay, among the three groups, suggesting that genetic instability, as assessed by this method, may not be a primary driver of the distinct clinical presentations observed in post-COVID syndromes. However, when gender was considered, male participants in the acute long COVID group exhibited higher levels of genetic instability compared to females. Multiple linear regression analysis revealed that gender, age, and waist circumference were significant predictors of DNA damage. Among females in the acute group, sexual health, and eye-related symptoms significantly influenced the increase in DNA damage. These findings indicate the need for further investigation on the gender-specific differences in genetic instability and their potential implications for the pathophysiology of post-COVID syndromes. Exploring alternative markers of genetic instability and the interplay between genetic, inflammatory, and cellular processes could provide valuable insights for the management of these debilitating post-viral sequelae.

Relative frequency of genomic mutations in SARS-CoV-2 recovered from southern Brazilian cases of COVID-19 through the Gamma, Delta and Omicron waves.

The presence of different mutations in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome can be related to changes in coronavirus disease (COVID-19) infection. Besides, these viral alterations associated with factors such as massive number of positive cases, vaccination and reinfections can be important in the viral evolution process. As well as, mutations found at low frequencies may have a more neutral action and consequently be less inclined to negative selection, facilitating their spread through the population. Related to that, we aimed to present mutations that are possibly relevant in the process of viral evolution found in 115 SARS-CoV-2 sequences from samples of individuals residing in the metropolitan region of Porto Alegre in the state of Rio Grande do Sul, Brazil. The genome from clinical samples was sequenced using High-Throughput Sequencing (HTS) and analyzed using a workflow to map reads and find variations/SNPs. The samples were separated into 3 groups considering the sample lineage. Of the total number of analyzed sequences, 35 were from the Gamma lineage, 35 from Delta and 45 from Omicron. Amino acid changes present in frequencies lower than 80% of the reads in the sequences were evaluated. 11 common mutations among the samples were found in the Gamma lineage, 1 in the ORF1ab gene, 7 in the S gene, 2 in the ORF6 gene and 1 in the ORF7a gene. While in the Delta lineage, a total of 11 mutations distributed in the ORF1ab, S, ORF7a and N genes, 2, 7, 1 and 1 mutation were found in each gene, respectively. And finally, in the Omicron, 16 mutations were identified, 2 in the ORF1ab gene, 12 in the S gene and 2 in the M gene. In conclusion, we emphasize that genomic surveillance can be a useful tool to assess how mutations play a key role in virus adaptation, and its process of susceptibility to new hosts showing the possible signs of viral evolution.

Evaluation of Mastadenovirus and Rotavirus Presence in Phyllostomid, Vespertilionid, and Molossid Bats Captured in Rio Grande do Sul, Southern Brazil.

Bat-borne viruses may affect public health and the global economy. These mammals have a wide geographical distribution and unique biological, physiological, and immunogenic characteristics, allowing the dissemination of many known and unknown viruses. Enteric viruses, such as adeno (AdV) and rotaviruses, are recognized as the main causative agents of disease and outbreaks. In the present study, the presence of viruses from Adenoviridae and Reoviridae families was evaluated in molossid, phyllostomid, and vespertilionid bats captured in Rio Grande do Sul, Southern Brazil, between September 2021 and July 2022. Sixty bat rectal swabs were analyzed by PCR. Eight (13.3%) samples were positive for adenovirus and classified as human mastadenovirus C (HAdV-C) (three samples) and HAdV-E (five samples) by sequencing followed by phylogenetic analysis. All samples were negative in rotavirus specific RT-PCR. This is the first study to describe the presence of HAdV in samples of Glossophaga soricina, Eptesicus brasiliensis, and Histiotus velatus. Furthermore, the presence of HAdV-E in bats was reported, which is unusual and may suggest that other HAdV genotypes, in addition to HAdV-C, may also be harbored by wild animals. The data generated in the present study reinforces the importance of eco-surveillance of viral agents related to diseases in humans and wild animals. In addition, it is essential to identify possible new hosts or reservoirs that increase the risk of spillover and dissemination of infectious pathogens, helping to prevent and control zoonotic diseases.

DENV-1 genotype V linked to the 2022 dengue epidemic in Southern Brazil.

Even though Brazil is a country where the dengue virus (DENV) is endemic, until recently, Southern states did not have significant viral circulation, such as Rio Grande do Sul (RS), and some municipalities were even considered dengue-free. During 2022, these places have shown a sharp increase in the incidence of the disease, apparently following a worldwide growth pattern. Therefore, in this study, we monitor and characterize the genetic diversity of DENV circulating in southern Brazil through next-generation sequencing during an outbreak in 2022. We generated 70 DENV-1 genome sequences, all characterized as genotype V, divided into two clade clusters in the L1 lineage. Furthermore, unique mutations have been described in each clade of L1 lineage. Our results are essential in managing outbreaks since these data provide important information during the emergence of DENV circulation in RS. Since the south of Brazil has a lower viral circulation when compared to other Brazilian states, RS still lacks data that can help in understanding the transmission, dissemination, and evolution of the dengue virus. Hence, genomic surveillance efforts are essential to increase the accuracy of preventive actions and to control viral dissemination.

Reinfection by SARS-CoV-2 by divergent Omicron sublineages, 16 days apart.

Since the beginning of the SARS-CoV-2 pandemic, studies on the variants and sublineages stand out, mainly in the cases of reinfection in a short period. In this study, we describe a case of infection by BA.1.1 sublineage in an individual from Southern Brazil. The same patient acquired reinfection with sublineage BA.2 within 16 days after the first detection. The viral extraction and RT-qPCR were performed on the samples LMM72045 (collected in May 2022) and LMM72044 (collected in June 2022). After the confirmation of SARS-CoV-2 infection, we conducted the sequencing and viral genome analysis. This case of reinfection affected a 52-year-old male patient, without comorbidities, with three doses of vaccines against COVID-19, showing symptoms on May 19. These symptoms lasted for approximately six days. The patient returned to work activities on May 30. However, on June 4, the patient felt a new round of clinical signs that lasted for approximately seven days. Analysis of the viral genomes recovered from patients' clinical samples revealed that the two COVID-19 episodes were related to two divergent VOC Omicron sublineages, namely, BA.1.1 for the first round of symptoms and BA.2 for the second infection. Based on our findings, we can say that the present case of reinfection is the shortest described so far.

Dynamics of nosocomial SARS-CoV-2 transmissions: Facing the challenge of variants of concern in a Brazilian reference hospital.

The hospital environment can be considered a high risk for the occurrence of SARS-CoV-2 transmission outbreaks, either for health professionals who are directly involved in the care of suspected or confirmed cases of the disease, or for patients, for being in an environment more vulnerable to the acquisition of nosocomial infections. In this molecular epidemiology study, we aimed to analyze the occurrence and transmission dynamics of SARS-CoV-2 in outbreaks and local chains of transmission in a large tertiary teaching hospital in southern Brazil, in addition to verifying circulating strains and their epidemiological relation in the local context, from September 21, 2020 to October 5, 2021. Positive samples involved in COVID-19 clusters or outbreaks were analyzed using clinical, epidemiological and genomic data. Different lineages and sublineages among patients in the same room were observed. Most patients had their first clinical manifestation, evidence of suspicion, and diagnostic confirmation within 7-14 days or >14 days after hospital admission. The patients who have contact with confirmed cases of COVID-19 spent, on average, 6.28 days in the same environment until the positive test. There was a significant association between the outcome and the number of vaccine doses (p < 0.05), where those who received two doses presented a lower occurrence of death. There was a total replacement of variant of concern (VOC) Gamma by VOC Delta from August 2021 at the study site. Although the epidemiological analysis indicates nosocomial infections, through genomic sequencing, it was established that most of the hospital outbreaks had different origins. These findings highlight the utility of integrating epidemiological and genomic data to identify possible routes of viral entry and dissemination.

Cytotoxicity evaluation of haloperidol, clozapine and a new molecule with antipsychotic potential, PT-31, in NIH-3T3 cells

Abstract Schizophrenia is an illness that affects 26 million people worldwide. However, conventional antipsychotics present side effects and toxicity, highlighting the need for new antipsychotics. We aimed to evaluate the cytotoxicity of haloperidol (HAL), clozapine (CLO), and a new molecule with antipsychotic potential, PT-31, in NIH-3T3 cells. The neutral red uptake assay and the MTT assay were performed to evaluate cell viability and mitochondrial activity, morphological changes were assessed, and intracellular reactive oxygen species (ROS) detection was performed. HAL and CLO (0.1 µM) showed a decrease in cell viability in the neutral red uptake assay and in the MTT assay. In addition, cell detachment, content decrease, rounding and cell death were also observed at 0.1 µM for both antipsychotics. An increase in ROS was observed for HAL (0.001, 0.01 and 1 µM) and CLO (0.01 and 1 µM). PT-31 did not alter cell viability in any of the assays, although it increased ROS at 0.01 and 1 µM. HAL and CLO present cytotoxicity at 0.1 µM, possibly through apoptosis and necrosis. In contrast, PT-31 does not present cytotoxicity to NIH-3T3 cells. Further studies must be performed for a better understanding of these mechanisms and the potential risk of conventional antipsychotics

HIV-1 genetic diversity and transmitted drug resistance to integrase strand transfer inhibitors among recently diagnosed adults in Porto Alegre, South Brazil.

OBJECTIVES: The HIV-1 genetic diversity and the presence of transmitted drug resistance mutations (TDRMs) against integrase strand transfer inhibitors (INSTIs) were assessed sequencing samples of antiretroviral (ARV)-naive HIV-1-infected individuals from South Brazil. METHODS: Viral RNA from 42 ART-naive individuals was submitted to complete HIV-1 integrase gene amplification by RT-PCR and sequencing. RESULTS: Viral strains carrying TDRMs against INSTIs were not detected in the present study. However, the polymorphisms L74M and L74I were each observed in 4.8% of the individuals. These accessory mutations have been reported as putative causes of TDRMs in ART with raltegravir, but only when associated with additional major mutations. When submitted to HIV-1 subtyping, 50% were classified as subtype C, 21% as recombinant BC, 19% as subtype B, 4.8% as subtype F1 and 4.8% as recombinant CF1. CONCLUSIONS: All 42 ARV-naive individuals were apparently susceptible to INSTIs, included in the Brazilian therapeutic guideline since 2009. To the best of our knowledge, this is the first study to evaluate TDRMs against INSTIs in Brazil. The most prevalent HIV-1 subtypes were subtype C, followed by the recombinant BC and subtype B, which is in agreement with previous studies. However, the presence of subtype F1 and recombinant CF1 reported herein was not observed in previous studies.

Genomic and epidemiologic surveillance of SARS-CoV-2 in Southern Brazil and identification of a new Omicron-L452R sublineage.

Recently, SARS-CoV-2 Omicron variant (B.1.1.529) was first identified in Botswana in November 2021. In a short period of time, this highly mutated variant replaced the previous dominant Delta variant, causing an exponential increase in the number of COVID-19 cases, resulting in a new wave of pandemic. This current research article aims to analyze and summarize information about the genetic characteristics, amino acid mutations and epidemiological data providing scientific findings to enrich the SARS-CoV-2 knowledge. More importantly, we describe here, for the first time, the identification of a new Omicron variant of concern: Omicron-L452R in Brazil.