Multiplex sample-sparing assay for detecting type-specific antibodies to Zika and dengue viruses: an assay development and validation study.

Background: Serology for dengue viruses (DENV) and Zika virus (ZIKV) has been hindered by antibody cross-reactivity, which limits the utility of these tests for surveillance and assessment of sero-status. Our aim was to develop a multiplexed IgG-based assay with increased accuracy to assess the history of previous DENV and ZIKV infections.

Methods: We developed and assessed the analytical performance of a sample-sparing, multiplexed, microsphere-based serological assay using domain III of the envelope protein (EDIII) of DENV serotypes 1-4 and ZIKV, the most variable region between each virus.

Serotype-specific epidemiological patterns of inapparent versus symptomatic primary dengue virus infections: a 17-year cohort study in Nicaragua.

Background: Dengue is the most prevalent mosquito-borne viral disease and a major public health problem worldwide. Most primary infections with the four dengue virus serotypes (DENV1-4) are inapparent; nonetheless, whether the distribution of symptomatic versus inapparent infections by serotype varies remains unknown. Here, we present (1) the evaluation of a DENV1-4 envelope domain III multiplex microsphere-based assay (EDIII-MMBA) to serotype inapparent primary infections and (2) its application leveraging 17 years of prospective sample collection from the Nicaraguan Pediatric Dengue Cohort Study (PDCS).

High transmission of endemic human coronaviruses before and during the COVID-19 pandemic in adolescents in Cebu, Philippines.

Background: SARS-CoV-2, the causative agent of COVID-19, is a betacoronavirus belonging to the same genus as endemic human coronaviruses (hCoVs) OC43 and HKU1 and is distinct from alpha hCoVs 229E and NL63. In a study of adolescents in the Philippines, we evaluated seroprevalence to the hCoVs, whether pre-pandemic hCoV immunity modulated subsequent risk of SARS-CoV-2 infection, and if SARS-CoV-2 infection affected the transmission of the hCoVs.

Methods: From 499 individuals screened in 2021 for SARS-CoV-2 receptor binding domain (RBD) antibodies by enzyme-linked immunosorbent assay (ELISA), we randomly selected 59 SARS-CoV-2 negative and 61 positive individuals for further serological evaluation.

Oral SARS-CoV-2 host responses predict the early COVID-19 disease course.

Oral fluids provide ready detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and host responses. This study sought to evaluate relationships between oral virus, oral and systemic anti-SARS-CoV-2-specific antibodies, and symptoms. Oral fluids (saliva/throat wash (saliva/TW)) and serum were collected from asymptomatic and symptomatic, nasopharyngeal (NP) SARS-CoV-2 RT-qPCR+ human participants (n = 45).