Polina Ivanova, Rinat Sagdiev, Anton Zverev 4 分钟阅读 * Many participants had already quit to seek vaccination * Current volunteers will not be “unblinded” * Other vaccine makers facing same ethical challenge By Polina Ivanova, Rinat Sagdiev and Anton Zverev MOSCOW, Dec 22 (Reuters) - Russia stopped taking in new volunteers in the trial of its first vaccine against COVID-19 on Wednesday, with developers saying it was unethical to administer a placebo to participants now that the shot was increasingly available to the public. Russia began rolling out the Sputnik V vaccine as part of ...