ABSTRACT
Chagas disease (CD), caused by Trypanosoma cruzi, is underdiagnosed in the United States. Improved screening strategies are needed, particularly for people at risk for life-threatening sequelae of CD, including people with human immunodeficiency virus (HIV, PWH). Here we report results of a CD screening strategy applied at a large HIV clinic serving an at-risk population.
Subject(s)
Chagas Disease , HIV Infections , Trypanosoma cruzi , Humans , United States/epidemiology , HIV , Chagas Disease/diagnosis , Chagas Disease/epidemiology , Chagas Disease/complications , HIV Infections/diagnosis , HIV Infections/epidemiology , HIV Infections/complicationsABSTRACT
Introduction. One correlate of immunity for coronavirus disease 2019 (COVID-19) is the laboratory detection of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies. These tests are widely implemented for clinical, public health, or research uses.Hypothesis/Gap Statement. Antibody responses by all classes of immunoglobulins may form from infection and vaccination, but few studies have performed direct head-to-head comparisons between these groups.Aim. The objective of this study was to evaluate the serological responses in natural SARS-CoV-2 infection and mRNA-based vaccination across multiple immunoglobulin classes and a surrogate neutralizing antibody (NAb) assay.Methodology. A suite of enzyme-linked immunosorbent assays (ELISAs) was used to qualitatively assess IgA, IgM and IgG positivity and neutralizing per cent signal inhibition of sera from RT-PCR-confirmed SARS-CoV-2-infected patients, COVID-19-immunized individuals ≥2 weeks after a second dose of mRNA vaccine and a set of pre-pandemic negative samples.Results. For confirmed SARS-CoV-2 infections, seroconversion of IgA, IgM, IgG and NAb increased by week after symptom onset, with positivity reaching 100â% after the third week for every immunoglobulin class. Vaccinated individuals demonstrated 100â% IgG positivity and high per cent signal inhibition by NAb, comparable to natural infection. High specificity, ranging from 96.7-98.9â%, was observed for each assay from a set of pre-pandemic COVID-19-negative samples.Conclusion. We make use of a comprehensive and readily adoptable suite of serological assays to provide data on the humoral immune response to SARS-CoV-2 infection and vaccination. We found that infection and vaccination both elicit robust IgG, IgM, IgA and neutralizing antibody responses.
