Shigayeva Altynay, Kandel Christopher, Farooqi Lubna, Zhong Zoe, Gingras Anne-Claude, Coleman Brenda L, Gilbert Lois, Gold Wayne L, Major Maria, Mazzulli Tony, Mubareka Samira, Vojicic Jelena, Yang Jingyan, Zhang Pingping, Martin Catherine, Kyaw Moe H, McLaughlin John M, McGeer Allison
Department of Microbiology, Sinai Health, Toronto, Canada.
Michael Garron Hospital, Toronto East Health Network, Toronto, Canada.
BMC Infect Dis. 2025 Feb 8;25(1):194. doi: 10.1186/s12879-024-10331-1.
Predictions regarding the on-going burden of SARS-CoV-2, and vaccine recommendations, require an understanding of infection-associated immune protection. We assessed whether early COVID-19 provided protection against Omicron infection.
We enrolled a cohort of adults in Ontario, Canada, with COVID-19 prior to October 2020 (early infection, EI), and a matched cohort with COVID-19 testing and a negative PCR (non-EI). Participants completed baseline surveys then surveys every two weeks until January 2023. Multivariable Cox regression was used to assess factors associated with COVID-19 infection during the first 14 months of Omicron.
Overall, 624 EI (70%) and 175 (77%) non-EI participants met criteria for analysis; 590 (95%) EI and 164 (94%) non-EI had received at least 2 COVID-19 vaccine doses prior to Omicron. Of 624 EI, 175 (28%) had one SARS-CoV-2 re-infection and 8 (1.3%) had two, compared to 84 (48%) non-EI participants with one, 5 (2.9%) with two and 1 (0.6%) with 3 infections (P < 0.0001). In multivariable analysis of risk factors for Omicron infection, the overall hazard ratio (HR, 95%CI) associated with EI was 0.56 (0.43-0.74); HRs for BA.1/2, BA.4/5 and mixed BA.5/BQ.1/XBB periods were 0.66 (0.45-0.97), 0.44 (0.28-0.68) and 0.71 (0.32-1.56). EI and BA.1/2 infection combined reduced later Omicron infection (HR 0.07 (0.03-0.21) compared to no prior infection. Older age, non-White ethnicity, no children in household, and lower neighbourhood income were associated with reduced risk of infection.
In our highly vaccinated population, early SARS-CoV-2 infection was associated with a 44% reduction in symptomatic COVID-19 during the first 14 months of Omicron, providing significant protection against re-infection for more than 2 years.
要预测严重急性呼吸综合征冠状病毒2（SARS-CoV-2）持续存在的负担以及疫苗接种建议，就需要了解感染相关的免疫保护情况。我们评估了早期冠状病毒病（COVID-19）是否能预防奥密克戎感染。
我们招募了加拿大安大略省一组在2020年10月之前感染过COVID-19的成年人（早期感染，EI），以及一组匹配的接受过COVID-19检测且聚合酶链反应（PCR）结果为阴性的人群（非EI）。参与者完成基线调查，然后每两周进行一次调查，直至2023年1月。采用多变量Cox回归分析来评估在奥密克戎出现的前14个月中与COVID-19感染相关的因素。
总体而言，624名EI参与者（70%）和175名（77%）非EI参与者符合分析标准；590名（95%）EI参与者和164名（94%）非EI参与者在奥密克戎出现之前已接种至少2剂COVID-19疫苗。在624名EI参与者中，175名（28%）出现过1次SARS-CoV-2再次感染，8名（1.3%）出现过2次；相比之下，84名（48%）非EI参与者出现过1次，5名（2.9%）出现过2次，1名（0.6%）出现过3次感染（P<0.0001）。在对奥密克戎感染风险因素的多变量分析中，与EI相关的总体风险比（HR，95%置信区间）为0.56（0.43 - 0.74）；在BA.1/2、BA.4/5以及混合的BA.5/BQ.1/XBB流行期，HR分别为0.66（0.45 - 0.97）、0.44（0.28 - 0.68）和0.71（0.32 - 1.56）。EI和BA.1/2感染共同作用可降低后期奥密克戎感染风险（与无既往感染相比，HR为0.07（0.03 - 0.21））。年龄较大、非白人种族、家中无子女以及邻里收入较低与感染风险降低相关。
在我们这个高疫苗接种率的人群中，早期SARS-CoV-2感染与奥密克戎出现的前14个月中有症状COVID-19感染率降低44%相关，为超过2年的再次感染提供了显著保护。
