Using sero-epidemiology to monitor disparities in vaccination and infection with SARS-CoV-2

Abstract

As SARS-CoV-2 continues to spread and vaccines are rolled-out, the “double burden” of disparities in exposure and vaccination intersect to determine patterns of infection, immunity, and mortality. Serology provides a unique opportunity to measure prior infection and vaccination simultaneously. Leveraging algorithmically-selected residual sera from two hospital networks in the city of San Francisco, cross-sectional samples from 1,014 individuals from February 4–17, 2021 were each tested on two assays (Ortho Clinical Diagnostics VITROS Anti-SARS-CoV-2 and Roche Elecsys Anti-SARS-CoV-2), capturing the first year of the epidemic and early roll-out of vaccination. We estimated, using Bayesian estimation of infection and vaccination, that infection risk of Hispanic/Latinx residents was five times greater than of White residents aged 18–64 (95% Credible Interval (CrI): 3.2–10.3), and that White residents over 65 were twice as likely to be vaccinated as Black/African American residents (95% CrI: 1.1–4.6). We found that socioeconomically-deprived zipcodes had higher infection probabilities and lower vaccination coverage than wealthier zipcodes. While vaccination has created a ‘light at the end of the tunnel’ for this pandemic, ongoing challenges in achieving and maintaining equity must also be considered.

Accounting for assay performance when estimating the temporal dynamics in SARS-CoV-2 seroprevalence in the U.S.

“…These surveys and other convenience and representative seroprevalence studies (refs. 8 , 10 – 21 ; also see https://covid19serohub.nih.gov ) have provided estimates of the cumulative proportion of the population with a history of at least one infection with SARS-CoV-2 in the United States at the national and local level. Modeling approaches have also used seroprevalence studies to improve estimates of critical parameters (e.g., the infection fatality rate) or to compare to model outputs 3 , 4 , 22 .…”

Accounting for assay performance when estimating the temporal dynamics in SARS-CoV-2 seroprevalence in the U.S

“…Since July 2020, commercial laboratories have conducted regular nationwide serosurveys for the CDC ( Bajema et al, 2021 ; Clarke et al, 2022 ). These surveys and other convenience and representative seroprevalence studies ( Havers et al, 2020 ; Naranbhai et al, 2020 ; Anand et al, 2020 ; Menachemi et al, 2020 ; Venugopal et al, 2021 ; Bajema et al, 2021 ; Lamba et al, 2021 ; Bruckner et al, 2021 ; Kline et al, 2021 ; Kalish et al, 2021 ; Jones et al, 2021 ; Sullivan et al, 2022 ; Routledge et al, 2022 ; also see https://covid19serohub.nih.gov) have provided estimates of the cumulative proportion of the population with a history of at least one infection with SARS-CoV-2 in the United States at the national and local level. Modeling approaches have also used seroprevalence studies to improve estimates of critical parameters (e.g., the infection fatality rate) or to compare to model outputs ( Irons and Raftery, 2021 ; Lu et al, 2021 ; Chitwood et al, 2022 ).…”

Wastewater as a back door to serology?

“…13 Currently rates of boosting in countries such as the United States are low and highly biased between populations. 46 As predicting the local impact of the next SARS-CoV-2 infection wave requires an estimate of the durability of the immune response from earlier vaccination or natural infection, wastewater-based assessments could allow such data to be rapidly collected and thereby identify populations at risk.…”