Different longitudinal patterns of nucleic acid and serology testing results based on disease severity of COVID-19 patients

Abstract

Effective strategy to mitigate the ongoing pandemic of 2019 novel coronavirus (COVID-19) require a comprehensive understanding of humoral responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the emerging virus causing COVID-19. The dynamic profile of viral replication and shedding along with viral antigen specific antibody responses among COVID-19 patients started to be reported but there is no consensus on their patterns. Here, we conducted a serial investigation on 21 individuals infected with SARS-CoV-2 in two medical centres from Jiangsu Province, including 11 non-severe COVID-19 patients, and 5 severe COVID-19 patients and 5 asymptomatic carriers based on nucleic acid test and clinical symptoms. The longitudinal swab samples and sera were collected from these people for viral RNA testing and antibody responses, respectively. Our data revealed different pattern of seroconversion among these groups. All 11 non-severe COVID-19 patients and 5 severe COVID-19 patients were seroconverted during hospitalization or follow-up period, suggesting that serological testing is a complementary assay to nucleic acid test for those symptomatic COVID-19 patients. Of note, immediate antibody responses were identified among severe cases, compared to non-severe cases. On the other hand, only one were seroconverted for asymptomatic carriers. The SARS-CoV-2 specific antibody responses were well-maintained during the observation period. Such information is of immediate relevance and would assist COVID-19 clinical diagnosis, prognosis and vaccine design.

Coronavirus disease 2019 3 months after hematopoietic stem cell transplant: A pediatric case report

“…However, symptom severity may also affect the rate of seropositivity. A delayed or absent humoral response against SARS‐CoV‐2 has been reported in some patients 12 and may result in negative serology results 13 . Surprisingly, despite her immunosuppressed condition and her mild symptoms, she developed an immune response with IgM produced on day 14, which is consistent with the literature for immunocompetent patients 14 .…”

COVID‐19 Clinical Diagnostics and Testing Technology

“…56 Asymptomatic patients may seroconvert later in the course of infection or may not at all. 57 Another study found that asymptomatic patients have significantly longer duration of viral shedding, lower IgG, and neutralizing serum antibody levels compared with the symptomatic group, suggesting that asymptomatic patients may mount a weaker antibody response and immunity may diminish within months of infection. 58 Although these studies demonstrate variable antibody response, IgA/IgM antibodies seem to develop during the earlier stages (indicative of recent exposure) 59 whereas IgG antibodies show up later in the course of SARS-CoV-2 infection.…”

Detection of SARS-CoV-2 antibodies is insufficient for the diagnosis of active or prior COVID-19

“…IgG detection may improve and speed up the diagnosis of COVID-19 in symptomatic patients, particularly in negative SARS-CoV-2 PCR cases. It has been shown that in up to 15% of COVID-19-positive patients IgG antibodies are detectable during the rst week following the onset of symptoms [8], although reaching 100% of the patients required two additional weeks [8,12,13,20]. Here, we examined the performance of serology as an adjuvant for the diagnosis of COVID-19 using commercially available procedures.…”