Barcelona Institute for Global Health (ISGlobal), 08036, Barcelona, Spain.
Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique.
Sci Rep. 2021 Nov 3;11(1):21571. doi: 10.1038/s41598-021-00807-4.
Sparse data exist on the complex natural immunity to SARS-CoV-2 at the population level. We applied a well-validated multiplex serology test in 5000 participants of a general population study in Catalonia in blood samples collected from end June to mid November 2020. Based on responses to fifteen isotype-antigen combinations, we detected a seroprevalence of 18.1% in adults (n = 4740), and modeled extrapolation to the general population of Catalonia indicated a 15.3% seroprevalence. Antibodies persisted up to 9 months after infection. Immune profiling of infected individuals revealed that with increasing severity of infection (asymptomatic, 1-3 symptoms, ≥ 4 symptoms, admitted to hospital/ICU), seroresponses were more robust and rich with a shift towards IgG over IgA and anti-spike over anti-nucleocapsid responses. Among seropositive participants, lower antibody levels were observed for those ≥ 60 years vs < 60 years old and smokers vs non-smokers. Overweight/obese participants vs normal weight had higher antibody levels. Adolescents (13-15 years old) (n = 260) showed a seroprevalence of 11.5%, were less likely to be tested seropositive compared to their parents and had dominant anti-spike rather than anti-nucleocapsid IgG responses. Our study provides an unbiased estimate of SARS-CoV-2 seroprevalence in Catalonia and new evidence on the durability and heterogeneity of post-infection immunity.
关于人群层面上对 SARS-CoV-2 的复杂自然免疫力，相关的稀疏数据依然存在。我们在 2020 年 6 月底至 11 月中旬采集的 5000 名加泰罗尼亚一般人群研究参与者的血液样本中应用了一种经过充分验证的多重血清学检测。基于对 15 种同种型抗原组合的反应，我们在成年人（n=4740）中检测到 18.1%的血清阳性率，并通过模型外推到加泰罗尼亚的一般人群，表明血清阳性率为 15.3%。感染后抗体持续存在长达 9 个月。对感染个体的免疫分析表明，随着感染严重程度的增加（无症状、1-3 种症状、≥4 种症状、住院/重症监护），血清反应更加稳健和丰富，IgG 取代 IgA，抗刺突取代抗核衣壳的反应。在血清阳性的参与者中，与<60 岁的人相比，≥60 岁的人抗体水平较低；与不吸烟者相比，吸烟者的抗体水平较低。超重/肥胖参与者的抗体水平高于正常体重者。青少年（13-15 岁）（n=260）的血清阳性率为 11.5%，与他们的父母相比，他们更不可能被检测为血清阳性，并且主要表现为抗刺突 IgG 反应，而不是抗核衣壳 IgG 反应。我们的研究提供了加泰罗尼亚 SARS-CoV-2 血清阳性率的无偏估计，并提供了关于感染后免疫的持久性和异质性的新证据。
