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Data for: Single versus serial dilution SARS-CoV-2 IgG

Cite this dataset

Fofana, Mariam (2023). Data for: Single versus serial dilution SARS-CoV-2 IgG [Dataset]. Dryad.


Reliable and scalable seroepidemiology methods are needed to estimate SARS-CoV-2 incidence and monitor the dynamics of population-level immunity as the pandemic evolves. We aimed to evaluate the reliability of SARS-CoV-2 normalized ELISA optical density (nOD) at a single dilution compared to titers derived from serial dilutions. We conducted serial serosurveys within a community-based cohort in Salvador, Brazil. Anti-S IgG ELISA (Euroimmun AG) was performed with five serial 3-fold dilutions of paired sera from 54 participants. Changes in nOD reliably predicted increases and decreases in titers (98.1% agreement, κ = 95.8%). Fitting the relationship between nOD and interpolated titers to a log-log curve yields highly accurate predictions of titers (r2 = 0.995) and changes in titers (r2 = 0.975), using only one to two dilutions. This approach can significantly reduce the time, labor and resources needed for large-scale serosurveys to ascertain population-level changes in exposure and immunity.

Usage notes

Data can be accessed using R.


National Institutes of Health

National Council for Scientific and Technological Development

Fundação de Amparo à Pesquisa do Estado da Bahia

Bill & Melinda Gates Foundation

American Society of Tropical Medicine and Hygiene

Wellcome Trust

Burroughs Wellcome Fund

Medical Research Council