Seroprevalence of SARS-CoV-2-Specific IgG Antibodies Among Adults Living in Connecticut: Post-Infection Prevalence (PIP) Study

UMMS Affiliation

Department of Pathology

Publication Date


Document Type



Amino Acids, Peptides, and Proteins | Epidemiology | Immunology of Infectious Disease | Immunopathology | Infectious Disease | Microbiology | Virus Diseases


BACKGROUND: A seroprevalence study can estimate the percentage of people with SARS-CoV-2 antibodies in the general population, however, most existing reports have used a convenience sample, which may bias their estimates.

METHODS: We sought a representative sample of Connecticut residents, aged > /=18 years and residing in non-congregate settings, who completed a survey between June 4 and June 23, 2020 and underwent serology testing for SARS-CoV-2-specific IgG antibodies between June 10 and July 29, 2020. We also oversampled non-Hispanic Black and Hispanic subpopulations. We estimated the seroprevalence of SARS-CoV-2-specific IgG antibodies and the prevalence of symptomatic illness and self-reported adherence to risk mitigation behaviors among this population.

RESULTS: Of the 567 respondents (mean age 50 [+/-17] years; 53% women; 75% non-Hispanic White individuals) included at the state-level, 23 respondents tested positive for SARS-CoV-2-specific antibodies, resulting in weighted seroprevalence of 4.0 (90% confidence interval [CI] 2.0-6.0). The weighted seroprevalence for the oversampled non-Hispanic Black and Hispanic populations was 6.4% (90% CI 0.9-11.9) and 19.9% (90% CI 13.2-26.6), respectively. The majority of respondents at the state-level reported following risk mitigation behaviors: 73% avoided public places, 75% avoided gatherings of families or friends, and 97% wore a facemask, at least part of the time.

CONCLUSIONS: These estimates indicate that the vast majority of people in Connecticut lack antibodies against SARS-CoV-2 and there is variation by race/ethnicity. There is a need for continued adherence to risk mitigation behaviors among Connecticut residents to prevent resurgence of COVID-19 in this region.


Antibodies, COVID-19, Connecticut, SARS-CoV-2, Seroprevalence

DOI of Published Version



Mahajan S, Srinivasan R, Redlich CA, Huston SK, Anastasio KM, Cashman L, Massey DS, Dugan A, Witters D, Marlar J, Li SX, Lin Z, Hodge D, Chattopadhyay M, Adams MD, Lee C, Rao LV, Stewart C, Kuppusamy K, Ko AI, Krumholz HM. Seroprevalence of SARS-CoV-2-Specific IgG Antibodies Among Adults Living in Connecticut: Post-Infection Prevalence (PIP) Study. Am J Med. 2020 Oct 29:S0002-9343(20)30909-8. doi: 10.1016/j.amjmed.2020.09.024. Epub ahead of print. PMID: 33130124; PMCID: PMC7598362. Link to article on publisher's site

Journal/Book/Conference Title

The American journal of medicine


This article is based on a previously available preprint on medRxiv that is also available in eScholarship@UMMS.

Full author list omitted for brevity. For the full list of authors, see article.

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