State Key Laboratory for Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China.
State Key Laboratory for Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China; Department of Microbiology, Queen Mary Hospital, Pokfulam, Hong Kong Special Administrative Region, China.
EBioMedicine. 2023 Feb;88:104446. doi: 10.1016/j.ebiom.2023.104446. Epub 2023 Jan 25.
Vaccination reduces COVID-19-related hospitalization among older adults. However, how SARS-CoV-2 infection and vaccine regimens affect vaccine-elicited immunity remain unclear.
This is a cross-sectional study recruiting adults aged ≥70 years with comorbidities in Hong Kong. Demographic and clinical information were collected using a questionnaire. Neutralizing antibody (nAb) titers (against ancestral and Omicron strains) and SARS-CoV-2-specific T cell response were analyzed according to infection and vaccination status. Multivariable regression analysis was performed to assess the associations of BNT162b2 and booster doses with higher nAb titers, with adjustment for comorbidities.
In July 2022, 101 patients were recruited, of whom 25 (24%) had previous infection. Overall, the geometric mean titer (GMT) of BA.5 nAb was 2.8-fold lower than that against BA.2 (P < 0.0001). The ancestral strain and BA.2 titers were higher for the 3-4-dose-BNT162 group than the 2-dose-BNT162b2 group. Non-infected individuals in the 3-4-dose-CoronaVac group had a more robust T cell response than the 2-dose-CoronaVac group (P = 0.0181), but there was no significant difference between the 2-dose-BNT162b2 and 3-4-dose-BNT162b groups. Patients who had heterologous CoronaVac-BNT162b2 prime-boost regimen had 3.22-fold higher BA.5 nAb titers than those who were primed/boosted with CoronaVac (P = 0.0207). Patients with hybrid immunity had higher Omicron nAb titers than those with vaccine-only immunity. Multivariable analysis showed that BNT162b2 and booster doses were independently associated with higher ancestral strain nAb titers.
Our data support the use of booster doses for older adults with or without prior infection. Non-infected individuals primed with CoronaVac will benefit from heterologous mRNA vaccine booster.
Richard and Carol Yu, May Tam Mak Mei Yin, The Shaw Foundation Hong Kong, Michael Tong, Marina Lee, Government Consultancy Service (See acknowledgements for full list).
疫苗接种可降低老年人与 COVID-19 相关的住院率。然而，SARS-CoV-2 感染和疫苗方案如何影响疫苗引起的免疫仍不清楚。
这是一项在香港招募有合并症的 70 岁以上成年人的横断面研究。使用问卷收集人口统计学和临床信息。根据感染和疫苗接种状况分析中和抗体（nAb）滴度（针对原始和奥密克戎株）和 SARS-CoV-2 特异性 T 细胞反应。多变量回归分析评估了 BNT162b2 和加强剂量与更高 nAb 滴度的关联，调整了合并症。
2022 年 7 月，招募了 101 名患者，其中 25 名（24%）有既往感染。总体而言，BA.5 nAb 的几何平均滴度（GMT）比 BA.2 低 2.8 倍（P<0.0001）。3-4 剂 BNT162 组的原始株和 BA.2 滴度高于 2 剂 BNT162b2 组。CoronaVac 组的未感染者比 CoronaVac 组的 2 剂组具有更强的 T 细胞反应（P=0.0181），但 2 剂 BNT162b2 组和 3-4 剂 BNT162b2 组之间没有显著差异。接受 CoronaVac-BNT162b2 异源初免-加强方案的患者 BA.5 nAb 滴度比接受 CoronaVac 初免/加强方案的患者高 3.22 倍（P=0.0207）。混合免疫的患者比仅接种疫苗的患者具有更高的奥密克戎 nAb 滴度。多变量分析显示，BNT162b2 和加强剂量与较高的原始株 nAb 滴度独立相关。
我们的数据支持为有或没有既往感染的老年人使用加强剂量。用 CoronaVac 进行初免的未感染者将受益于异源 mRNA 疫苗加强。
Richard and Carol Yu、May Tam Mak Mei Yin、The Shaw Foundation Hong Kong、Michael Tong、Marina Lee、政府顾问服务（详见致谢）。
