Dynamic Change and Clinical Relevance of Postinfectious SARS-CoV-2 Antibody Responses

Abstract

Background Although reports suggest that most individuals with COVID-19 develop detectable antibodies post infection, the kinetics, durability, and relative differences between IgM and IgG responses beyond the first few weeks after symptom onset remain poorly understood. Methods Within a large, well-phenotyped, diverse, prospective cohort of subjects with and without SARS-CoV-2 PCR-confirmed infection and historical controls derived from cohorts with high prevalence of viral coinfections and samples taken during prior flu seasons, we measured SARS-CoV-2 serological responses (both IgG and IgM) using commercially available assays. We calculated sensitivity and specificity, relationship with disease severity and mapped the kinetics of antibody responses over time using generalised additive models. Results We analysed 1,001 samples from 752 subjects, 327 with confirmed SARS-CoV-2 (29.7% with severe disease) spanning a period of 90 days from symptom onset. Sensitivity was lower (44.1-47.1%) early (<10 days) after symptom onset but increased to >80% after 10 days. IgM positivity increased earlier than IgG-targeted assays but positivity peaked between day 32 and 38 post onset of symptoms and declined thereafter, a dynamic that was confirmed when antibody levels were analysed, with more rapid decline observed with IgM. Early (<10 days) IgM but not IgG levels were significantly higher in those who subsequently developed severe disease (signal / cut-off 4.20 (0.75-17.93) versus 1.07 (0.21-5.46), P=0.048). Conclusions This study suggests that post-infectious antibody responses in those with confirmed COVID-19 begin to decline relatively early post infection and suggests a potential role for higher IgM levels early in infection predicting subsequent disease severity

Persistence of Anti-SARS-CoV-2 IgM Antibody up to 8 Months Post-COVID-19

“…In recent study, Mallon et al [9] reported that in subjects diagnosed with COVID-19, the IgM positivity was increased earlier, with the positivity peaking between days 32 and 38 post-onset of symptoms, but with a more rapid decline than the observed to IgG. Additionally, in a longitudinal study, Peghin et al [10] observed IgM seroconversion in 90% of patients and its decline within 4 months.…”

Association of Lung Fibrotic Changes and Cardiological Dysfunction with Hypertension in Long COVID-19 cohort

“…The IgM antibodies at COVID-19 infection peak early and rapidly decline (rev. Huang AT et al, 2020; Mallon et al, 2021; Štěpánek et al, 2022). IgM seropositivity was found to be correlating with a symptom duration (Štěpánek et al, 2022).…”

Exploring the Role of Serology Testing to Strengthen Vaccination Initiatives and Policies for COVID-19 in Asia Pacific Countries and Territories: A Discussion Paper

“…Although vaccines are less effective against symptomatic disease and infection, effectiveness against severe disease remains high for Omicron, especially after booster doses [26]. Although serology tests are still effective in detecting antibodies to Omicron [290] and predicting the risk of hospitalization and severity of disease [281,291], studies suggest that Omicron breakthrough infections can happen even in individuals with high concentrations of antibodies [292]. Nonetheless, in such cases, it was also observed that infections are primarily mild or asymptomatic [290].…”