Abstract
Background
Individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) who do not report symptoms throughout the course of infection (asymptomatic) or those who are asymptomatic when they first contract the virus (presymptomatic) are a major public health concern. However, few prevalence studies to date have targeted the question of asymptomatic frequency within a community.
Methods
A stratified, random sample of subjects were sent to testing sites to complete a verbal consent, survey, nasopharyngeal swab, and blood draw. Swabs were tested for active viral shedding (PCR) and blood was tested for immunoglobulin G (IgG) specific to SARS-CoV-2.
Disease progression and IgG antibody response
Results
Of the 2,640 subjects, 24 (0·9%) were PCR-positive alone, 30 (1·1%) were PCR-positive and IgG-positive, and 129 (4·9%) were IgG-positive alone. Subjects who reported anosmia were 17 times more likely to test positive. Thirty-eight percent of subjects never experienced symptoms despite developing antibodies to the virus, and 75% did not experience symptoms in the early stage of infection. Rates of reported asymptomatic infection and comorbidities statistically significantly increased with age.
Conclusion
This is the first randomized study that pairs PCR and IgG serology that addresses asymptomatic SARS-CoV-2 infection, showing a high frequency of asymptomatic disease. More research is needed to clarify differences between symptomatic and asymptomatic disease. Prevalence and outcomes studies of SARS-CoV-2 should include this group.
Disclosures
All Authors: No reported disclosures