Comparative epidemic expansion of SARS-CoV-2 variants Delta and Omicron in Amazonas, a Brazilian setting with high levels of hybrid immunity

The SARS-CoV-2 variants of concern (VOCs) Delta and Omicron spread globally during mid and late 2021, respectively, with variable impact according to the immune population landscape. In this study, we compare the dissemination dynamics of these VOCs in the Amazonas state, one of Brazils most heavily affected regions. We sequenced the virus genome from 4,128 patients collected in Amazonas between July 1st, 2021 and January 31st, 2022 and investigated the lineage replacement dynamics using a phylodynamic approach. The VOCs Delta and Omicron displayed similar patterns of phylogeographic spread but significantly different epidemic dynamics. The Delta and Omicron epidemics were fueled by multiple introduction events, followed by the successful establishment of a few local transmission lineages of considerable size that mainly arose in the Capital, Manaus. The VOC Omicron spread and became dominant much faster than the VOC Delta. We estimate that under the same epidemiological conditions, the average Re of Omicron was [~]3.3 times higher than that of Delta and the average Re of the Delta was [~]1.3 times higher than that of Gamma. Furthermore, the gradual replacement of Gamma by Delta occurred without an upsurge of COVID-19 cases, while the rise of Omicron fueled a sharp increase in SARS-CoV-2 infection. The Omicron wave displayed a shorter duration and a clear decoupling between the number of SARS-CoV-2 cases and deaths compared with previous (B.1.* and Gamma) waves in the Amazonas state. These findings suggest that the high level of hybrid immunity (infection plus vaccination) acquired by the Amazonian population by mid-2021 was able to limit the spread of the VOC Delta and was also probably crucial to curb the number of severe cases, although not the number of VOC Omicron new infections.

Spread of Gamma (P.1) sub-lineages carrying Spike mutations close to the furin cleavage site and deletions in the N-terminal domain drives ongoing transmission of SARS-CoV-2 in Amazonas, Brazil

The Amazonas was one of the most heavily affected Brazilian states by the COVID-19 epidemic. Despite a large number of infected people, particularly during the second wave associated with the spread of the Variant of Concern (VOC) Gamma (lineage P.1), SARS-CoV-2 continues to circulate in the Amazonas. To understand how SARS-CoV-2 persisted in a human population with a high immunity barrier, we generated 1,188 SARS-CoV-2 whole-genome sequences from individuals diagnosed in the Amazonas state from 1st January to 6th July 2021, of which 38 were vaccine breakthrough infections. Our study reveals a sharp increase in the relative prevalence of Gamma plus (P.1+) variants, designated as Pango Lineages P.1.3 to P.1.6, harboring two types of additional Spike changes: deletions in the N-terminal (NTD) domain (particularly{Delta} 144 or{Delta} 141-144) associated with resistance to anti-NTD neutralizing antibodies or mutations at the S1/S2 junction (N679K or P681H) that probably enhance the binding affinity to the furin cleavage site, as suggested by our molecular dynamics simulations. As lineages P.1.4 (S:N679K) and P.1.6 (S:P681H) expanded (Re > 1) from March to July 2021, the lineage P.1 declined (Re < 1) and the median Ct value of SARS-CoV-2 positive cases in Amazonas significantly decreases. Still, we found no overrepresentation of P.1+ variants among breakthrough cases of fully vaccinated patients (71%) in comparison to unvaccinated individuals (93%). This evidence supports that the ongoing endemic transmission of SARS-CoV-2 in the Amazonas is driven by the spread of new local Gamma/P.1 sub-lineages that are more transmissible, although not more efficient to evade vaccine-elicited immunity than the parental VOC. Finally, as SARS-CoV-2 continues to spread in human populations with a declining density of susceptible hosts, the risk of selecting new variants with higher infectivity are expected to increase.

The ongoing evolution of variants of concern and interest of SARS-CoV-2 in Brazil revealed by convergent indels in the amino (N)-terminal domain of the Spike protein

Mutations at both the receptor-binding domain (RBD) and the amino (N)-terminal domain (NTD) of the SARS-CoV-2 Spike (S) glycoprotein can alter its antigenicity and promote immune escape. We identified that SARS-CoV-2 lineages circulating in Brazil with mutations of concern in the RBD independently acquired convergent deletions and insertions in the NTD of the S protein, which altered the NTD antigenic-supersite and other predicted epitopes at this region. These findings support that the ongoing widespread transmission of SARS-CoV-2 in Brazil is generating new viral lineages that might be more resistant to neutralization than parental variants of concern.

Miniexame do estado mental: capacidade psicométrica e formas de avaliação / Minimental state examination: psychometric capacity and forms of assessment

As transições demográfica e epidemiológica ocorridas nos últimos anos produziram, como efeito, o envelhecimento populacional. Devido a isso, são necessárias informações atualizadas desse segmento, destacando-se as relacionadas à saúde. Entre os problemas de saúde que afetam especialmente os idosos, o déficit cognitivo tem consequências diretas sobre a qualidade de vida dos mesmos, sendo caracterizado pela deterioração das habilidades intelectuais. O Miniexame do Estado Mental (MEEM) é um instrumento de rastreamento de deterioração cognitiva, utilizado internacionalmente, que fornece informações sobre diferentes dimensões cognitivas, tais como orientação, memória, cálculo e linguagem. Ainda não há consenso na literatura quanto ao ponto de corte mais adequado na sua utilização e sua capacidade psicométrica. Nesse contexto, o objetivo do presente estudo é realizar uma revisão de literatura, através das bases de dados contidas na Biblioteca Virtual em Saúde (BVS), para maiores esclarecimentos das indicações, capacidade psicométrica e formas de avaliação do MEEM, para elucidar sua utilização em estudos epidemiológicos.

Demographic and epidemiological transitions have occurred in recent years, producing the effect of population aging. Because of this, updated information is needed in this segment, especially related to health. Among the health problems that particularly affect the elderly, cognitive impairment has direct consequences on their quality of life, characterized by cognitive decline. The Mini-Mental State Examination (MMSE) is a screening tool for cognitive impairment, used internationally, that provides information about different cognitive dimensions such as orientation, memory, judgment, and language. There is no consensus in the literature regarding the most appropriate cutoff point in its use and its psychometric capacity. In this context, the objective of this study is a literature review, through the databases contained in the Virtual Health Library (VHL), for further clarification of the indicated uses, psychometric capacity, and forms of evaluation of the MMSE, to clarify its use in epidemiological studies.

Nutritional Status Associated with Metabolic Syndrome in Middle-School Children in the City of Montes Claros - MG, Brazil.

The aim of this study was to investigate the association between nutritional status and prevalence of metabolic syndrome (MS) in middle-school students in the city of Montes Claros - MG. The sample consisted of 382 students, aged 10-16 years. Nutritional status was evaluated using the Body Mass Index (BMI). Metabolic syndrome (MS) was defined as the presence of two or more criteria in accordance with definition of the International Diabetes Federation. The overall prevalence of MS was 7.9%. 9.7% of students with MS were overweight and 72.4% were obese. Therefore, it can be inferred that carrying excess weight considerably increases the chances for a child to develop MS, and concomitantly increases the child's risk for developing cardiovascular disease.

Avaliação da rugosidade superficial e da dureza de diferentes cerâmicas odontológicas / Evaluated the superficial roughness and hardness the differents porcelain dentals

Para avaliação da abrasividade de 4 tipos de porcelanas para sistemas metal free: Vision Esthetic, Vitadur Alpha, Ducera Gold e Procera All Ceram foi analizada a rugosidade superficial média(Ra) antes e após a ciclagem mecânica e, realizado o teste de dureza Vickers das superfícies cerâmicas glazeadas opondo-se ao esmalte dental. Foram utilizados 20 fragmentos de esmalte humano e 10 discos de cada tipo de cerâmica. Após o glazeamento dos discos cerâmicos foram submetidos à ciclagem mecânica de 30.000 ciclos (carga axial: 3 kg, velocidade: 2,3Hz, temperatura: 37° por 24 horas) tendo como meio, água e resina autopolimerizável. As amostras foram submetidas a testes de dureza Vickers em um microdurômetro (5 endentações, carga de 9,8N por 15 segundos) e avaliadas em um rugosímetro (ponta analisadora de superfície em 3 posições diferentes). Resultados encontrados: a mais alta média de rugosidade superficial foi apresentada pela cerâmica da baixa fusão Vision Esthetic e a menor pela All Ceram. A mais alta média de dureza Vickers foi encontrada nas cerâmicas Vitadur Alpha e Vision Esthetic e a menor pela All Ceram, diferindo dos demais materiais. Todas as cerâmicas apresentaram maior dureza e rugosidade que o esmalte dental e este os maiores índices de rugosidade. Concluindo-se que, a análise quantitativa da rugosidade superficial (Ra) não é parâmetro suficiente para correlacioná-la ao desgaste sendo importante avaliar a matriz vítrea da cerâmica assim como a resistência à fratura e dureza do material cerâmico