Timing the SARS-CoV-2 index case in Hubei province
Jonathan Pekar, Michael Worobey,Niema Moshiri, Konrad Scheffler, Joel O. Wertheim
Science 18 Mar 2021: DOI: 10.1126/science.abf8003
核心内容：Our results define the period between mid-October and mid-November 2019 as the plausible interval when the first case of SARS-CoV-2 emerged in Hubei province.
PMCID: PMC7799215
PMID: 33252659 Clin Infect Dis.
Serologic testing of U.S. blood donations to identify SARS-CoV-2-reactive antibodies: December 2019-January 2020
Methods
To determine if SARS-CoV-2 reactive antibodies were present in sera prior to the first identified case in the U.S. on January 19, 2020, residual archived samples from 7,389 routine blood donations collected by the American Red Cross from December 13, 2019 to January 17, 2020, from donors resident in nine states (California, Connecticut, Iowa, Massachusetts, Michigan, Oregon, Rhode Island, Washington, and Wisconsin) were tested at CDC for anti-SARS-CoV-2 antibodies. Specimens reactive by pan-immunoglobulin (pan Ig) enzyme linked immunosorbent assay (ELISA) against the full spike protein were tested by IgG and IgM ELISAs, microneutralization test, Ortho total Ig S1 ELISA, and receptor binding domain / Ace2 blocking activity assay.
Results
Of the 7,389 samples, 106 were reactive by pan Ig. Of these 106 specimens, 90 were available for further testing. Eighty four of 90 had neutralizing activity, 1 had S1 binding activity, and 1 had receptor binding domain / Ace2 blocking activity >50%, suggesting the presence of anti-SARS-CoV-2-reactive antibodies. Donations with reactivity occurred in all nine states.
加州大学圣地牙哥分校发表在《科学》（Science）的最新研究发现，中国湖北新冠肺炎的零号病患，最早可能出现在2019年10月7日，后来才在武汉华南海鲜市场发生疫情。
根据《每日邮报》报导，研究作者佩卡尔（Jonathan Pekar）博士等人分析湖北583份早期病毒样本，研究人员认为，这种从动物身上传染到人类体内的病毒，其初代是1种极弱的病毒株，很快就灭绝了，但是在它消失前产生了突变种，进而传播到武汉乃至于世界各国。
佩卡尔指出，在这份研究的分析中，最初的病毒株若是在农村出现，它必须转移到城市才有办法继续生存，在2019年11月与12月初，中国各地没看见关于新冠肺炎的相关消息，这表明当时病毒还在湖北省建立传播链，因此，零号病患与华南海鲜批发市场的距离可能较远。
该研究假定2019年11月17日的这株病毒株是最早被记录到的，透过电脑模型推算，考量到传播、检测、症状出现等因素，零号病患可能最早出现在该年的10月7日。