Impact of COVID-19 on the epidemiology of respiratory viruses in southern Brazil

Background and objectives: During the SARS-CoV-2 pandemic, reduction in detection of other Respiratory Viruses (RV) was observed. Epidemiological studies are needed to understand the impact of the pandemic on the circulation of RV. The aim of this study is to analyze the epidemiological profile of cases of severe acute respiratory infection (SARI) associated with the main RV in hospitalized patients from RS, between 2010 and 2019 (period A) and between 2020 and 2021 (period B). Methods: Data related to SARI cases in RS were retrieved from SIVEP-Gripe. Results: In period A there were more infections with Influenza, Parainfluenza, Adenovirus and Respiratory Syncytial Virus, while in period B most cases were of SARS-CoV-2 infection. The most affected age groups were individuals 60 years old (50%) in period B. The main symptoms were fever and cough in period A, and dyspnea and O2saturation <95% in period B. The most reported comorbidities were lung diseases and chronic cardiovascular diseases in period A, and chronic cardiovascular diseases and diabetes mellitus in period B. Importantly, a higher fatality rate was observed in period B. Most cases occurred between May and July in period A, and in November and December 2021 in period B. Conclusion: This study reveals that the COVID-19 pandemic changed the epidemiological profile of SARI in RS, and most cases were in the elderly with chronic cardiovascular disease and diabetes mellitus

Epidemiological investigation reveals local transmission of SARS-CoV-2 lineage P.1 in Southern Brazil

Since its detection in December of 2020, the SARS-CoV2 lineage P.1, descendent of B.1.1.28 lineage, has been identified in several places in Brazil and abroad. This Variant of Concern was considered highly prevalent in Northern Brazil and now is rapidly widening its geographical range. Here, we present epidemiological and genomic information of the first case of P1 lineage in Rio Grande do Sul state, in a patient with no reported travel history and a tracked transmission chain. These findings occurred in a tourist destination representing an important hub receiving tourists from diverse places

Recurrent dissemination of SARS-CoV-2 through the Uruguayan–Brazilian border

Uruguay is one of the few countries in the Americas that successfully contained the coronavirus disease 19 (COVID-19) epidemic during the first half of 2020. Nevertheless, the intensive human mobility across the dry border with Brazil is a major challenge for public health authorities. We aimed to investigate the origin of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains detected in Uruguayan localities bordering Brazil as well as to measure the viral flux across this ∼1,100 km uninterrupted dry frontier. Using complete SARS-CoV-2 genomes from the Uruguayan–Brazilian bordering region and phylogeographic analyses, we inferred the virus dissemination frequency between Brazil and Uruguay and characterized local outbreak dynamics during the first months (May–July) of the pandemic. Phylogenetic analyses revealed multiple introductions of SARS-CoV-2 Brazilian lineages B.1.1.28 and B.1.1.33 into Uruguayan localities at the bordering region. The most probable sources of viral strains introduced to Uruguay were the Southeast Brazilian region and the state of Rio Grande do Sul. Some of the viral strains introduced in Uruguayan border localities between early May and mid-July were able to locally spread and originated the first outbreaks detected outside the metropolitan region. The viral lineages responsible for Uruguayan urban outbreaks were defined by a set of between four and 11 mutations (synonymous and non-synonymous) with respect to the ancestral B.1.1.28 and B.1.1.33 viruses that arose in Brazil, supporting the notion of a rapid genetic differentiation between SARS-CoV-2 subpopulations spreading in South America. Although Uruguayan borders have remained essentially closed to non-Uruguayan citizens, the inevitable flow of people across the dry border with Brazil allowed the repeated entry of the virus into Uruguay and the subsequent emergence of local outbreaks in Uruguayan border localities. Implementation of coordinated bi-national surveillance systems is crucial to achieve an efficient control of the SARS-CoV-2 spread across this kind of highly permeable borderland regions around the world

Human metapneumovirus in Southern Brazil

Abstract INTRODUCTION Infections caused by respiratory viruses are important problems worldwide, especially in children. Human metapneumovirus (hMPV) is a respiratory pathogen and causes severe infections with nonspecific symptoms. This study reports the hMPV occurrence and dissemination in southern Brazil and compares the frequency of occurrence of this virus and the human respiratory syncytial virus (hRSV) in the epidemiological weeks in a three-year period (2009-2011). METHODS: In total, 545 nasopharyngeal (NP) specimens from individuals with Severe Acute Respiratory Syndrome (SARS) who were negative for other seven respiratory viruses were analyzed for the presence of hMPV. Human metapneumovirus was detected by direct immunofluorescence and real-time reverse transcription polymerase chain reaction. RESULTS: hMPV was detected in 109 patients from the main geographic regions of the southernmost state of Brazil, presenting similar overall prevalence in males (46.8%) and females (53.2%). Among children who were less than six years old, hMPV was detected in 99 samples of all age groups, with a higher frequency in infants who were less than one year old (45.7%) compared to all other age groups until six years. hMPV and hRSV infection occurred in almost the same epidemiological weeks (EWs) of each year, with peaks of incidence between EW 31/37 and EW 26/38 for the years 2009 and 2011, respectively. hMPV was further detected in several cases of SARS and it was the only virus detected in three deaths. CONCLUSIONS These findings indicate that hMPV is in circulation in southern Brazil and highlight the importance of diagnosing hMPV for influenza-like illness in the population