Objective To estimate the change in odds of covid-19 over time following primary series completion of the inactivated whole virus vaccine CoronaVac (Sinovac Biotech) in São Paulo State, Brazil. Design Test negative case-control study. Setting Community testing for covid-19 in São Paulo State, Brazil. Participants Adults aged ≥18 years who were residents of São Paulo state, had received two doses of CoronaVac, did not have a laboratory confirmed SARS-CoV-2 infection before vaccination, and underwent reverse transcription polymerase chain reaction (RT-PCR) testing for SARS-CoV-2 from 17 January to 14 December 2021. Cases were matched to test negative controls by age (in 5 year bands), municipality of residence, healthcare worker status, and epidemiological week of RT-PCR test. Main outcome measures RT-PCR confirmed symptomatic covid-19 and associated hospital admissions and deaths. Conditional logistic regression was adjusted for sex, number of covid-19 associated comorbidities, race, and previous acute respiratory illness. Results From 202 741 eligible people, 52 170 cases with symptomatic covid-19 and 69 115 test negative controls with covid-19 symptoms were formed into 43 257 matched sets. Adjusted odds ratios of symptomatic covid-19 increased with time since completion of the vaccination series. The increase in odds was greater in younger people and among healthcare workers, although sensitivity analyses suggested that this was in part due to bias. In addition, the adjusted odds ratios of covid-19 related hospital admission or death significantly increased with time compared with the odds 14-41 days after series completion: from 1.25 (95% confidence interval 1.04 to 1.51) at 70-97 days up to 1.94 (1.41 to 2.67) from 182 days onwards. Conclusions Significant increases in the risk of moderate and severe covid-19 outcomes occurred three months after primary vaccination with CoronaVac among people aged 65 and older. These findings provide supportive evidence for the implementation of vaccine boosters in these populations who received this inactivated vaccine. Studies of waning should include analyses designed to uncover common biases. Deidentified databases as well as the R codes will be deposited in the repository .

中文翻译：

---

接种 CoronaVac 疫苗后 covid-19 风险随时间的变化：测试阴性病例对照研究

目的 评估在巴西圣保罗州完成灭活全病毒疫苗 CoronaVac（Sinovac Biotech）的初级系列后 covid-19 几率随时间的变化。设计试验阴性病例对照研究。在巴西圣保罗州设置 covid-19 社区测试。参与者年龄≥18 岁、居住在圣保罗州、接种过两剂 CoronaVac、在接种疫苗前未经过实验室确诊的 SARS-CoV-2 感染并接受逆转录聚合酶链反应 (RT-PCR) 检测的成年人2021 年 1 月 17 日至 12 月 14 日的 SARS-CoV-2。病例按年龄（5 年区间）、居住城市、医护人员身份和 RT-PCR 检测的流行病学周进行匹配以检测阴性对照。主要结果指标 RT-PCR 证实有症状的 covid-19 以及相关的住院和死亡。条件逻辑回归针对性别、covid-19 相关合并症的数量、种族和既往急性呼吸道疾病进行了调整。结果 从 202 741 名符合条件的人中，52 170 名有症状的 covid-19 病例和 69 115 名有 covid-19 症状的检测阴性对照被组成 43 257 个匹配组。自疫苗接种系列完成后，有症状的 covid-19 的调整后优势比随时间增加。年轻人和医护人员的几率增加更大，尽管敏感性分析表明这部分是由于偏见。此外，与系列完成后 14-41 天的几率相比，covid-19 相关住院或死亡的调整后几率比随时间显着增加：从 70-97 天的 1.25（95% 置信区间 1.04 到 1.51）上升到 1.94（1.41至 2.67) 从 182 天开始。结论 65 岁及以上的人群在初次接种 CoronaVac 疫苗三个月后，中度和重度 covid-19 结果的风险显着增加。这些发现为在这些接受了这种灭活疫苗的人群中实施疫苗加强剂提供了支持性证据。衰减研究应包括旨在发现常见偏见的分析。去识别化的数据库以及 R 代码将存放在存储库中 67) 从 182 天开始。结论 65 岁及以上的人群在初次接种 CoronaVac 疫苗三个月后，中度和重度 covid-19 结果的风险显着增加。这些发现为在这些接受了这种灭活疫苗的人群中实施疫苗加强剂提供了支持性证据。衰减研究应包括旨在发现常见偏见的分析。去识别化的数据库以及 R 代码将存放在存储库中 67) 从 182 天开始。结论 65 岁及以上的人群在初次接种 CoronaVac 疫苗三个月后，中度和重度 covid-19 结果的风险显着增加。这些发现为在这些接受了这种灭活疫苗的人群中实施疫苗加强剂提供了支持性证据。衰减研究应包括旨在发现常见偏见的分析。去识别化的数据库以及 R 代码将存放在存储库中 这些发现为在这些接受了这种灭活疫苗的人群中实施疫苗加强剂提供了支持性证据。衰减研究应包括旨在发现常见偏见的分析。去识别化的数据库以及 R 代码将存放在存储库中 这些发现为在这些接受了这种灭活疫苗的人群中实施疫苗加强剂提供了支持性证据。衰减研究应包括旨在发现常见偏见的分析。去识别化的数据库以及 R 代码将存放在存储库中.