UK study reports antibody responses linked to more severe COVID-19 in higher risk populations
UK longitudinal study reports seroconversion dynamics by IgG ELISA from 845 samples from 177 adults previously diagnosed with SARS-CoV-2 by RT-PCR.
Baseline characteristics included 34% white, 35% non-white, median (IQR) age 64 years (IQR: 52 to 77), 57% male, and 73% had one or more co-morbidities; 19% were defined as asymptomatic with no respiratory symptoms on admission.
Seroconversion was associated with older age, more comorbidities (especially hypertension and higher BMI), non-white race and higher inflammatory markers (CRP), but 8.5% of participants showed no evidence of seroconversion even weeks after infection.
Antibody responses were maintained for more than two months.
Overall, 25% (44/177) died after median (IQR) 19.1 days (14.8 to 24.8).
The paper concluded that longer studies are needed to find out the duration of humoral responses that contribute to protection against future SARS-CoV-2 exposures.
Staines HM et al. Dynamics of IgG seroconversion and pathophysiology of COVID-19 infections. MedRxiv. Pre-peer review paper. DOI: 10.1101/2020.06.07.20124636. (8 June 2020).
This report was first published on 12 July 2020.