Details

Autor(en) / Beteiligte

• Montague, Brian T
• Wipperman, Matthew F
• Hooper, Andrea T
• Hamon, Sara C
• Crow, Rowena
• Elemo, Femi
• Hersh, Lisa
• Langdon, Shaun
• Hamilton, Jennifer D
• O’Brien, Meagan P
• Simões, Eric A F

Titel

Anti-SARS-CoV-2 IgA Identifies Asymptomatic Infection in First Responders

Ist Teil von

• The Journal of infectious diseases, 2022-02, Vol.225 (4), p.578-586

Ort / Verlag

US: Oxford University Press

Erscheinungsjahr

2022

Quelle

Oxford Journals 2020 Medicine

Beschreibungen/Notizen

• Abstract Background Immunoglobulin A (IgA) is an important component of the early immune response to SARS-CoV-2. Prior serosurveys in high-risk groups employing IgG testing alone have provided discordant estimates. The potential added benefit of IgA in serosurveys has not been established. Methods Longitudinal serosurvey of first responders (police, emergency medical service providers, fire fighters, and other staff) employing 3 serologic tests (anti-spike IgA, anti-spike IgG, and anti-nucleocapsid IgG) correlated with surveys assessing occupational and nonoccupational risk, exposure to COVID-19, and illnesses consistent with COVID-19. Results Twelve percent of first responders in Colorado at baseline and 22% at follow-up were assessed as having SARS-CoV-2 infection. Five percent at baseline and 6% at follow-up were seropositive only for IgA. Among those IgA positive only at baseline, the majority (69%) had a positive antibody at follow-up; 45% of those infected at baseline and 33% at follow-up were asymptomatic. At all time points, the estimated cumulative incidence in our study was higher than that in the general population. Conclusions First responders are at high risk of infection with SARS-CoV-2. IgA testing identified a significant portion of cases missed by IgG testing and its use as part of serologic surveys may improve retrospective identification of asymptomatic infection. In a serosurvey of high-risk first responders, detection of IgA in the absence of detectable IgG identified individuals with mild or asymptomatic infection, which would have been missed based assessment of anti-spike or anti-nucleocapsid IgG.