UK Health Security Agency, London, UK.
NIHR Health Protection Research Unit in Vaccines and Immunisation, London School of Hygiene and Tropical Medicine, London, UK.
Nat Commun. 2022 Dec 12;13(1):7688. doi: 10.1038/s41467-022-35168-7.
Despite the availability of the ChAdOx1-S booster vaccine, little is known about the real-world effectiveness although clinical trials have demonstrated enhanced immunity following a ChAdOx1-S booster. In England 43,171 individuals received a ChAdOx1-S booster whilst 13,038,908 individuals received BNT162b2 in the same period. ChAdOx1-S booster recipients were more likely to be female (adjusted odds ratio (OR) 1.67 (1.64-1.71)), in a clinical risk group (adjusted OR 1.58 (1.54-1.63)), in the clinically extremely vulnerable group (adjusted OR 1.84 (1.79-1.89)) or severely immunosuppressed (adjusted OR 2.05 (1.96-2.13)). The effectiveness of the ChAdOx1-S and BNT162b2 boosters is estimated here using a test-negative case-control study. Protection against symptomatic disease with the Omicron variant peaks at 66.1% (16.6 to 86.3%) and 68.5% (65.7 to 71.2%) for the ChAdOx1-S and BNT162b2 boosters in older adults. Protection against hospitalisation peaks at 82.3% (64.2 to 91.3%) and 90.9% (88.7 to 92.7%). For Delta, effectiveness against hospitalisation is 80.9% (15.6% to 95.7%) and 93.9% (92.8% to 94.9%) after ChAdOx1-S and BNT162b2 booster vaccination. This study supports the consideration of ChAdOx1-S booster vaccination for protection against severe COVID-19 in settings yet to offer boosters and suggests that individuals who received a ChAdOx1-S booster do not require re-vaccination ahead of others.
尽管已经有 ChAdOx1-S 加强型疫苗可用，但目前对于其实际效果知之甚少，尽管临床试验已经表明，ChAdOx1-S 加强型疫苗接种后可增强免疫力。在同一时期，英国有 43171 人接种了 ChAdOx1-S 加强型疫苗，而有 13038908 人接种了 BNT162b2 疫苗。ChAdOx1-S 加强型疫苗接种者更有可能是女性（调整后的优势比（OR）为 1.67（1.64-1.71）），处于临床风险组（调整后的 OR 为 1.58（1.54-1.63）），处于临床极度脆弱组（调整后的 OR 为 1.84（1.79-1.89））或严重免疫抑制（调整后的 OR 为 2.05（1.96-2.13））。在此，我们使用了一项测试阴性病例对照研究来估计 ChAdOx1-S 和 BNT162b2 加强型疫苗的有效性。针对 Omicron 变异株，ChAdOx1-S 和 BNT162b2 加强型疫苗对有症状疾病的保护作用峰值分别为 66.1%（16.6 至 86.3%）和 68.5%（65.7 至 71.2%），对老年人有效。针对住院治疗的保护作用峰值分别为 82.3%（64.2 至 91.3%）和 90.9%（88.7 至 92.7%）。对于 Delta，ChAdOx1-S 和 BNT162b2 加强型疫苗接种后，对住院治疗的有效性分别为 80.9%（15.6%至 95.7%）和 93.9%（92.8%至 94.9%）。本研究支持在尚未提供加强型疫苗的地区考虑接种 ChAdOx1-S 加强型疫苗以预防严重 COVID-19，并表明接种了 ChAdOx1-S 加强型疫苗的人不需要比其他人提前重新接种疫苗。
