Bennett Institute for Applied Data Science, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, OX2 6GG, UK.
London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
BMC Med. 2022 Jul 5;20(1):243. doi: 10.1186/s12916-022-02422-0.
While the vaccines against COVID-19 are highly effective, COVID-19 vaccine breakthrough is possible despite being fully vaccinated. With SARS-CoV-2 variants still circulating, describing the characteristics of individuals who have experienced COVID-19 vaccine breakthroughs could be hugely important in helping to determine who may be at greatest risk.
With the approval of NHS England, we conducted a retrospective cohort study using routine clinical data from the OpenSAFELY-TPP database of fully vaccinated individuals, linked to secondary care and death registry data and described the characteristics of those experiencing COVID-19 vaccine breakthroughs.
As of 1st November 2021, a total of 15,501,550 individuals were identified as being fully vaccinated against COVID-19, with a median follow-up time of 149 days (IQR: 107-179). From within this population, a total of 579,780 (<4%) individuals reported a positive SARS-CoV-2 test. For every 1000 years of patient follow-up time, the corresponding incidence rate (IR) was 98.06 (95% CI 97.93-98.19). There were 28,580 COVID-19-related hospital admissions, 1980 COVID-19-related critical care admissions and 6435 COVID-19-related deaths; corresponding IRs 4.77 (95% CI 4.74-4.80), 0.33 (95% CI 0.32-0.34) and 1.07 (95% CI 1.06-1.09), respectively. The highest rates of breakthrough COVID-19 were seen in those in care homes and in patients with chronic kidney disease, dialysis, transplant, haematological malignancy or who were immunocompromised.
While the majority of COVID-19 vaccine breakthrough cases in England were mild, some differences in rates of breakthrough cases have been identified in several clinical groups. While it is important to note that these findings are simply descriptive and cannot be used to answer why certain groups have higher rates of COVID-19 breakthrough than others, the emergence of the Omicron variant of COVID-19 coupled with the number of positive SARS-CoV-2 tests still occurring is concerning and as numbers of fully vaccinated (and boosted) individuals increases and as follow-up time lengthens, so too will the number of COVID-19 breakthrough cases. Additional analyses, to assess vaccine waning and rates of breakthrough COVID-19 between different variants, aimed at identifying individuals at higher risk, are needed.
尽管 COVID-19 疫苗具有高度有效性，但即使已完全接种疫苗，COVID-19 疫苗突破仍有可能发生。随着 SARS-CoV-2 变体的持续传播，描述经历 COVID-19 疫苗突破的个体的特征对于帮助确定哪些人面临最大风险可能非常重要。
在获得 NHS 英格兰的批准后，我们使用来自 OpenSAFELY-TPP 数据库中完全接种疫苗个体的常规临床数据，对该数据库进行了回顾性队列研究，这些数据与二级护理和死亡登记数据相关联，并描述了经历 COVID-19 疫苗突破的个体的特征。
截至 2021 年 11 月 1 日，共有 15501550 人被确定为完全接种了 COVID-19 疫苗，中位随访时间为 149 天（IQR：107-179）。在该人群中，共有 579780 人（<4%）报告 SARS-CoV-2 检测呈阳性。每 1000 年患者随访时间，相应的发病率（IR）为 98.06（95%CI 97.93-98.19）。共有 28580 例与 COVID-19 相关的住院治疗，1980 例与 COVID-19 相关的重症监护入院治疗和 6435 例与 COVID-19 相关的死亡；相应的 IR 分别为 4.77（95%CI 4.74-4.80）、0.33（95%CI 0.32-0.34）和 1.07（95%CI 1.06-1.09）。突破性 COVID-19 的最高发生率见于疗养院中的患者和患有慢性肾脏疾病、透析、移植、血液恶性肿瘤或免疫功能低下的患者。
尽管英格兰 COVID-19 疫苗突破病例的大多数为轻症，但在某些临床人群中已经发现突破病例的发生率存在差异。虽然需要注意的是，这些发现只是描述性的，不能用于回答为什么某些群体的 COVID-19 突破率高于其他群体，但 COVID-19 奥密克戎变体的出现以及 SARS-CoV-2 检测呈阳性的数量仍在持续增加令人担忧，随着完全接种（和加强接种）人数的增加和随访时间的延长，COVID-19 突破病例的数量也会增加。需要进一步分析，以评估不同变体之间的疫苗衰减和突破性 COVID-19 的发生率，目的是确定风险较高的个体。
