Gomes Bruno Belmonte Martinelli, Ferreira Natasha Nicos, Garibaldi Pedro Manoel Marques, Dias Cassia Fernanda Sales de Lima, Silva Letícia Nakamura, Almeida Maria Aparecida Alves Leite Dos Santos, de Moraes Glenda Renata, Covas Dimas Tadeu, Kashima Simone, Calado Rodrigo Tocantins, Fonseca Benedito Antônio Lopes, Volpe Gustavo Jardim, Borges Marcos de Carvalho
University of São Paulo, Ribeirão Preto Medical School, Avenida Bandeirantes, 3900, Ribeirão Preto, SP, Brazil.
Clinical Research Center - S, Rua Treze de Maio, 438, Serrana, SP, Brazil.
Heliyon. 2024 Nov 9;10(22):e40113. doi: 10.1016/j.heliyon.2024.e40113. eCollection 2024 Nov 30.
SARS-CoV-2 variants have distinct features of transmissibility, infectivity, and aggressiveness that may cause different clinical manifestations. A better understanding of the disease presentation and progression could help to outline more precise preventive and treatment frameworks. This study describes the differences in COVID-19 presentation and outcomes across five variant waves.
This prospective cohort was conducted in Serrana, São Paulo State, Brazil. Clinical and demographic data was obtained from June 2020 to December 2022 as part of an enhanced health surveillance system for COVID-19, based on increasing access to diagnostic testing for SARS-CoV-2 and patient follow-up. Individuals were assessed for COVID-19 symptoms and comorbidities. Mild cases were followed up for at least 14 days, and severe cases until discharge or death. Samples were genetically sequenced, and variant waves were determined based on global SARS-CoV-2 variant predominance (>90 % sequenced samples), being as follows: Ancestral, Delta, Gamma, Omicron BA.1, and Omicron BA.2 waves. The relationship between clinical data and disease outcomes was analyzed in each variant wave.
Patients infected during the Delta wave were the youngest (36.1 ± 18.2 years, p < 0.001). The proportion of female patients was higher across all waves. Positivity rate, disease severity, and COVID-19-related deaths varied among them. Ageusia and anosmia were related to SARS-CoV-2 positivity during the Ancestral, Gamma, and Delta waves but not in Omicron BA.1 and Omicron BA.2 waves. Diarrhea presented a lower chance of positivity only in Omicron BA.1 and Omicron BA.2. Dyspnea was the most consistent risk factor for severity across all waves.
Although patients with COVID-19 from different SARS-CoV-2 variants shared some clinical-epidemiological characteristics, each variant presented distinguishable features related to positivity and severity. This could help to understand the dynamics of COVID-19 variants and update recommendations for clinical practice.
严重急性呼吸综合征冠状病毒2（SARS-CoV-2）变体具有不同的传播性、传染性和侵袭性特征，可能导致不同的临床表现。更好地了解疾病表现和进展有助于制定更精确的预防和治疗框架。本研究描述了五个变体流行阶段中冠状病毒病（COVID-19）表现和结果的差异。
这项前瞻性队列研究在巴西圣保罗州的塞拉纳进行。作为COVID-19强化健康监测系统的一部分，从2020年6月至2022年12月获取临床和人口统计学数据，这基于对SARS-CoV-2诊断检测和患者随访的可及性增加。对个体进行COVID-19症状和合并症评估。轻症病例随访至少14天，重症病例随访至出院或死亡。对样本进行基因测序，并根据全球SARS-CoV-2变体优势（>90%测序样本）确定变体流行阶段，如下：原始毒株、德尔塔、伽马、奥密克戎BA.1和奥密克戎BA.2流行阶段。分析每个变体流行阶段临床数据与疾病结果之间的关系。
在德尔塔流行阶段感染的患者最年轻（36.1±18.2岁，p<0.001）。各流行阶段女性患者比例均较高。阳性率、疾病严重程度和COVID-19相关死亡在各阶段有所不同。嗅觉减退和嗅觉丧失在原始毒株、伽马和德尔塔流行阶段与SARS-CoV-2阳性相关，但在奥密克戎BA.1和奥密克戎BA.2流行阶段则不然。腹泻仅在奥密克戎BA.1和奥密克戎BA.2流行阶段阳性几率较低。呼吸困难是所有流行阶段严重程度最一致的危险因素。
尽管感染不同SARS-CoV-2变体的COVID-19患者有一些临床流行病学特征，但每个变体都呈现出与阳性率和严重程度相关的可区分特征。这有助于理解COVID-19变体的动态变化并更新临床实践建议。
