Barcelona Institute for Global Health, ISGlobal, Universitat Pompeu Fabra (UPF), Barcelona, Spain.
Pulmonary Division, Heart Institute, Hospital das Clínicas, Faculdade de Medicina, São Paulo, SP, Brazil.
Nat Commun. 2022 Oct 6;13(1):5536. doi: 10.1038/s41467-022-33169-0.
The effectiveness of inactivated vaccines (VE) against symptomatic and severe COVID-19 caused by omicron is unknown. We conducted a nationwide, test-negative, case-control study to estimate VE for homologous and heterologous (BNT162b2) booster doses in adults who received two doses of CoronaVac in Brazil in the Omicron context. Analyzing 1,386,544 matched-pairs, VE against symptomatic disease was 8.6% (95% CI, 5.6-11.5) and 56.8% (95% CI, 56.3-57.3) in the period 8-59 days after receiving a homologous and heterologous booster, respectively. During the same interval, VE against severe Covid-19 was 73.6% (95% CI, 63.9-80.7) and 86.0% (95% CI, 84.5-87.4) after receiving a homologous and heterologous booster, respectively. Waning against severe Covid-19 after 120 days was only observed after a homologous booster. Heterologous booster might be preferable to individuals with completed primary series inactivated vaccine.
在 Omicron 背景下，我们在巴西完成两剂科兴疫苗接种的成年人中开展了一项全国性、病例对照研究，旨在评估同源（接种科兴）和异源（接种 BNT162b2）加强针在预防由奥密克戎引起的有症状和重症 COVID-19 方面的有效性。在分析了 1386544 对匹配的病例对照后发现，接种同源加强针后 8-59 天，针对有症状疾病的疫苗有效性为 8.6%（95%CI，5.6-11.5），而异源加强针的有效性为 56.8%（95%CI，56.3-57.3）。在同一时间段内，接种同源和异源加强针后，针对重症 COVID-19 的疫苗有效性分别为 73.6%（95%CI，63.9-80.7）和 86.0%（95%CI，84.5-87.4）。仅在接种同源加强针 120 天后才观察到针对重症 COVID-19 的有效性下降。对于已完成基础系列灭活疫苗接种的个体，异源加强针可能是更好的选择。
