Lofgren Sarah M, Okafor Elizabeth C, Colette Alanna A, Pastick Katelyn A, Skipper Caleb P, Pullen Matthew F, Nicol Melanie R, Bold Tyler D, Bangdiwala Ananta S, Engen Nicole W, Collins Lindsey B, Williams Darlisha A, Axelrod Margaret L, Thielen Beth K, Hullsiek Kathy H, Boulware David R, Rajasingham Radha
Division of Infectious Diseases and International Medicine, Department of Medicine, University of Minnesota, Minneapolis, Minnesota, USA.
School of Medicine, University of Minnesota, Minneapolis, Minnesota, USA.
Open Forum Infect Dis. 2021 Oct 6;8(11):ofab506. doi: 10.1093/ofid/ofab506. eCollection 2021 Nov.
During the coronavirus disease 2019 (COVID-19) pandemic, clinical trials necessitated rapid testing to be performed remotely. Dried blood spot (DBS) techniques have enabled remote HIV virologic testing globally, and more recently, antibody testing as well. We evaluated DBS testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody testing in outpatients to assess seropositivity.
In 2020, we conducted 3 internet-based randomized clinical trials and offered serologic testing via self-collected DBS as a voluntary substudy. COVID-19 diagnosis was based on the Centers for Disease Control and Prevention case definition with epidemiological link to cases. A minority reported polymerase chain reaction (PCR) testing at an outside facility. We tested for anti-SARS-CoV-2 immunoglobulin via antibody detection by agglutination-PCR (ADAP) and compared the results with enzyme-linked immunosorbent assay (ELISA).
Of 2727 participants in the primary studies, 60% (1648/2727) consented for serology testing; 56% (931/1648) returned a usable DBS sample. Of those who were asymptomatic, 5% (33/707) had positive ADAP serology. Of participants with a positive PCR, 67% (36/54) had positive SARS-CoV-2 antibodies. None of those who were PCR-positive and asymptomatic were seropositive (0/7). Of 77 specimens tested for concordance via ELISA, 83% (64/77) were concordant. The challenges of completing a remote testing program during a pandemic included sourcing and assembling collection kits, delivery and return of the kits, and troubleshooting testing. Self-collection was successful for >95% of participants. Delays in US mail with possible sample degradation and timing of DBS collection complicated the analysis.
We found remote antibody testing during a global pandemic feasible although challenging. We identified an association between symptomatic COVID-19 and positive antibody results at a similar prevalence as other outpatient cohorts.
在2019冠状病毒病（COVID-19）大流行期间，临床试验需要进行远程快速检测。干血斑（DBS）技术已在全球范围内实现了远程HIV病毒学检测，最近也实现了抗体检测。我们评估了门诊患者中用于严重急性呼吸综合征冠状病毒2（SARS-CoV-2）抗体检测的DBS检测，以评估血清阳性率。
2020年，我们进行了3项基于互联网的随机临床试验，并将通过自我采集的DBS进行血清学检测作为一项自愿子研究。COVID-19诊断基于美国疾病控制与预防中心的病例定义以及与病例的流行病学关联。少数人报告在外部机构进行了聚合酶链反应（PCR）检测。我们通过凝集-PCR（ADAP）抗体检测法检测抗SARS-CoV-2免疫球蛋白，并将结果与酶联免疫吸附测定（ELISA）进行比较。
在主要研究的2727名参与者中，60%（1648/2727）同意进行血清学检测；56%（931/1648）返回了可用的DBS样本。在无症状者中，5%（33/707）的ADAP血清学检测呈阳性。在PCR检测呈阳性的参与者中，67%（36/54）的SARS-CoV-2抗体呈阳性。PCR检测呈阳性且无症状的参与者中无人血清学呈阳性（0/7）。在通过ELISA检测一致性的77份标本中，83%（64/77）结果一致。在大流行期间完成远程检测项目面临的挑战包括采购和组装采集试剂盒、试剂盒的交付和返还以及检测故障排除。超过95%的参与者成功进行了自我采集。美国邮政的延误可能导致样本降解以及DBS采集时间的问题使分析变得复杂。
我们发现，在全球大流行期间进行远程抗体检测虽然具有挑战性，但却是可行的。我们发现有症状的COVID-19与阳性抗体结果之间存在关联，其患病率与其他门诊队列相似。
