Specific COVID-19 Symptoms Correlate with High Antibody Levels against SARS-CoV-2

Lasting immunity will be critical for overcoming COVID-19. However, the factors associated with the development of high titers of anti–SARS-CoV-2 Abs and how long those Abs persist remain incompletely defined. In particular, an understanding of the relationship between COVID-19 symptoms and anti–SARS-CoV-2 Abs is limited. To address these unknowns, we quantified serum anti–SARS- CoV-2 Abs in clinically diverse COVID-19 convalescent human subjects 5 wk (n = 113) and 3 mo (n = 79) after symptom resolution with three methods: a novel multiplex assay to quantify IgG against four SARS-CoV-2 Ags, a new SARS-CoV-2 receptor binding domain-angiotensin converting enzyme 2 inhibition assay, and a SARS-CoV-2 neutralizing assay. We then identified clinical and demographic factors, including never-before-assessed COVID-19 symptoms, that consistently correlate with high anti–SARS-CoV-2 Ab levels. We detected anti–SARS-CoV-2 Abs in 98% of COVID-19 convalescent subjects 5 wk after symptom resolution, and Ab levels did not decline at 3 mo. Greater disease severity, older age, male sex, higher body mass index, and higher Charlson Comorbidity Index score correlated with increased anti–SARS-CoV-2 Ab levels. Moreover, we report for the first time (to our knowledge) that COVID-19 symptoms, most consistently fever, body aches, and low appetite, correlate with higher anti–SARS-CoV-2 Ab levels. Our results provide robust and new insights into the development and persistence of anti–SARS-CoV-2 Abs.