Fonseca Paula Luize Camargos, Braga-Paz Isabela, de Araújo E Santos Luiza Campos Guerra, Dias Rillery Calixto, de Souza Carolina Senra Alves, Carvalho Nara Oliveira, Queiroz Daniel Costa, Alves Hugo José, de Araújo João Locke Ferreira, Moreira Filipe Romero Rebello, Menezes Mariane Talon, Menezes Diego, Silva Aryel Beatriz Paz E, Ferreira Jorge Gomes Goulart, Adelino Talita Emile Ribeiro, Bernardes André Felipe Leal, Carobin Natália Virtude, Carvalho Renée Silva, Ferrari Carolina Zaniboni, Guimarães Natália Rocha, Lamounier Ludmila Oliveira, Souza Fernanda Gil, Vargas Luisa Aimeé, Ribeiro Marisa de Oliveira, Arruda Monica Barcellos, Alvarez Patricia, Moreira Rennan Garcias, de Oliveira Eneida Santos, Sabino Adriano de Paula, de Oliveira Jaqueline Silva, Januário José Nélio, Iani Felipe Campos de Melo, Souza Renan Pedra de, Aguiar Renato Santana
Laboratório de Biologia Integrativa, Departamento de Genética, Ecologia e Evolução, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte 31270-901, Brazil.
Subsecretaria de Vigilância em Saúde, Secretaria de Estado de Saúde de Minas Gerais, Belo Horizonte 31585-200, Brazil.
Microorganisms. 2024 Aug 23;12(9):1745. doi: 10.3390/microorganisms12091745.
Brazil is one of the countries most affected by COVID-19, with the highest number of deaths recorded. Brazilian Health Institutions have reported four main peaks of positive COVID-19 cases. The last two waves were characterized by the emergence of the VOC Omicron and its sublineages. This study aimed to conduct a retrospective surveillance study illustrating the emergence, dissemination, and diversification of the VOC Omicron in 15 regional health units (RHUs) in MG, the second most populous state in Brazil, by combining epidemiological and genomic data. A total of 5643 confirmed positive COVID-19 samples were genotyped using the panels TaqMan SARS-CoV-2 Mutation and 4Plex SC2/VOC Bio-Manguinhos to define mutations classifying the BA.1, BA.2, BA.4, and BA.5 sublineages. While sublineages BA.1 and BA.2 were more prevalent during the third wave, BA.4 and BA.5 dominated the fourth wave in the state. Epidemiological and viral genome data suggest that age and vaccination with booster doses were the main factors related to clinical outcomes, reducing the number of deaths, irrespective of the Omicron sublineages. Complete genome sequencing of 253 positive samples confirmed the circulation of the BA.1, BA.2, BA.4, and BA.5 subvariants, and phylogenomic analysis demonstrated that the VOC Omicron was introduced through multiple international events, followed by transmission within the state of MG. In addition to the four subvariants, other lineages have been identified at low frequency, including BQ.1.1 and XAG. This integrative study reinforces that the evolution of Omicron sublineages was the most significant factor driving the highest peaks of positive COVID-19 cases without an increase in more severe cases, prevented by vaccination boosters.
巴西是受新冠疫情影响最严重的国家之一，死亡人数位居全球前列。巴西卫生机构报告了新冠病毒阳性病例的四个主要高峰期。最后两波疫情的特点是出现了奥密克戎变异株（VOC）及其亚谱系。本研究旨在通过整合流行病学和基因组数据，对巴西人口第二多的米纳斯吉拉斯州（MG）的15个区域卫生单位（RHU）进行回顾性监测研究，以阐明奥密克戎变异株在该州的出现、传播和多样化情况。使用TaqMan SARS-CoV-2突变检测试剂盒和4Plex SC2/VOC Bio-Manguinhos检测板对总共5643份确诊的新冠病毒阳性样本进行基因分型，以确定对BA.1、BA.2、BA.4和BA.5亚谱系进行分类的突变。虽然BA.1和BA.2亚谱系在第三波疫情中更为普遍，但BA.4和BA.5在该州的第四波疫情中占主导地位。流行病学和病毒基因组数据表明，年龄和接种加强针是与临床结果相关的主要因素，无论奥密克戎亚谱系如何，均可减少死亡人数。对253份阳性样本进行的全基因组测序证实了BA.1、BA.2、BA.4和BA.5亚变体的传播，系统发育基因组分析表明，奥密克戎变异株是通过多次国际事件传入的，随后在米纳斯吉拉斯州内传播。除了这四个亚变体之外，还发现了其他低频谱系，包括BQ.1.1和XAG。这项综合研究强化了这样一个观点，即奥密克戎亚谱系的演变是导致新冠病毒阳性病例最高峰的最重要因素，而加强针接种可预防更严重病例的增加。
