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      <JournalTitle>Frontiers in Medical Case Reports</JournalTitle>
      <Volume-Issue>Volume 1; Issue 6</Volume-Issue>
      <Season>(Nov-Dec, 2020)</Season>
      <ArticleType>Medical Case Reports</ArticleType>
      <ArticleTitle>Asymptomatic SARS-CoV-2 Carriers may not Generate Antibodies: A Case Report</ArticleTitle>
      <Abstract>Asymptomatic SARS-CoV-2 carriers are infectious to some extent and can potentially transmit coronavirus disease 2019 (COVID-19). RNA assay combining antibody detection significantly improved the sensitivity of pathogenic diagnosis for COVID-19. Here, we report an asymptomatic case of COVID-19 with positive RNA but consistently negative antibodies (IgM and IgG). This case indicates that not everyone can generate specific antibodies after infection with SARS-CoV-2. The absence of antibodies means that the asymptomatic carriers like our case have no specific resistance to the virus and their plasm may do no good in the treatment of the other COVID-19 patients. As RNA detectability of COVID-19 patients is not too high and will further decrease with the duration of disease, negative antibodies results may miss diagnosis. Therefore, repeated nucleic acid assay and antibody test should be carried out for suspected cases.</Abstract>
      <Keywords>COVID-19,SARS-CoV-2,Asymptomatic Carrier,Antibody</Keywords>
        <Abstract>https://jmedicalcasereports.org/ubijournal-v1copy/journals/abstract.php?article_id=8630&amp;title=Asymptomatic SARS-CoV-2 Carriers may not Generate Antibodies: A Case Report</Abstract>
        <References>Bai Y, Yao L, Wei T, Tian F, Jin DY, Chen L, Wang M. Presumed Asymptomatic Carrier Transmission of COVID-19. JAMA 2020; 323: 1406-1407.&#13;
Baumgarth N. How specific is too specific? B-cell responses to viral infections reveal the importance of breadth over depth. Immunol Rev 2013; 255: 82-94.&#13;
Corman VM, Landt O, Kaiser M, Molenkamp R, Meijer A, Chu DK, Bleicker T, Brand;uuml;nink S, Schneider J, Schmidt ML, Mulders DG. Detection of 2019 novel coronavirus (2019-nCoV) by real-time RT-PCR. Euro Surveill 2020; 25: 2000045.&#13;
Duan K, Liu B, Li C, Zhang H, Yu T, Qu J, Zhou M, Chen L, Meng S, Hu Y, Peng C. Effectiveness of convalescent plasma therapy in severe COVID-19 patients. Proc Natl Acad Sci USA 2020; 117: 9490-9496.&#13;
Lam JH and Baumgarth N. The Multifaceted B Cell Response to Influenza Virus. J Immunol 2019; 202: 351-359.&#13;
Long QX, Liu BZ, Deng HJ, Wu GC, Deng K, Chen YK, Liao P, Qiu JF, Lin Y, Cai XF, Wang DQ. Antibody responses to SARS-CoV-2 in patients with COVID-19. Nat Med 2020; 29: 1-4.&#13;
Rothe C, Schunk M, Sothmann P, Bretzel G, Froeschl G, Wallrauch C, Zimmer T, Thiel V, Janke C, Guggemos W, Seilmaier M. Transmission of 2019-nCoV Infection from an Asymptomatic Contact in Germany. N Engl J Med 2020; 382: 970-971.&#13;
Wang Y, Liu Y, Liu L, Wang X, Luo N, Ling L. Clinical outcome of 55 asymptomatic cases at the time of hospital admission infected with SARS-Coronavirus-2 in Shenzhen, China. J Infect Dis 2020.&#13;
Xiang F, Wang X, He X, Peng Z, Yang B, Zhang J, Zhou Q, Ye H, Ma Y, Li H, Wei X. Antibody Detection and Dynamic Characteristics in Patients with COVID-19. Clin Infect Dis 2020; 71: 1930-1934&#13;
Yongchen Z, Shen H, Wang X, Shi X, Li Y, Yan J, Chen Y, Gu B. Different longitudinal patterns of nucleic acid and serology testing results based on disease severity of COVID-19 patients. Emerg Microbes Infect 2020; 9: 833-836.&#13;
Zhang J, Wu S, Xu L. Asymptomatic carriers of COVID-19 as a concern for disease prevention and control: more testing, more follow-up. Biosci Trends 2020.&#13;
Zhang L, Pang R, Xue X, Bao J, Ye S, Dai Y et al. Anti-SARS-CoV-2 virus antibody levels in convalescent plasma of six donors who have recovered from COVID-19. Aging (Albany NY) 2020; 12: 6536-6542.&#13;
Zhang L, Zhang F, Yu W, He T, Yu J, Yi CE, Ba L, Li W, Farzan M, Chen Z, Yuen KY. Antibody responses against SARS coronavirus are correlated with disease outcome of infected individuals. J Med Virol 2006; 78: 1-8.&#13;
Zhao J, Yuan Q, Wang H, Liu W, Liao X, Su Y, Wang X, Yuan J, Li T, Li J, Qian S. Antibody responses to SARS-CoV-2 in patients of novel coronavirus disease 2019. Clin Infect Dis 2020.&#13;
Zhu N, Zhang D, Wang W, Li X, Yang B, Song J, Zhao X, Huang B, Shi W, Lu R, Niu P. A Novel Coronavirus from Patients with Pneumonia in China, 2019. N Engl J Med 2020; 382: 727-733.</References>