Fifty - three subjects had a positive test on initial elisa screening ; seven of them were confirmed as true positives . among these seven positive cases , only one had asymptomatic infection 在五十三个初步测试呈阳性反应的样本当中;七个样本最终确定有sars冠状病毒抗体存在,其中只有一个样本是来自隐形病人。