The Trajectory of Antibody Responses One Year Following SARS-CoV-2 Infection among Indigenous Individuals in the Southwest United States.

SARS-CoV-2 antibody kinetics based on immunologic history is not fully understood. We analyzed anti-spike and anti-nucleocapsid antibody responses following acute infection in a cohort of Indigenous persons. The models of peak concentrations and decay rates estimated that one year after infection, participants would serorevert for anti-nucleocapsid antibodies and remain seropositive for anti-spike antibodies.

Effectiveness of COVID-19 mRNA Vaccines in Preventing COVID-19-Associated Outpatient Visits and Hospitalizations Among American Indian and Alaska Native Persons, January-November 2021: A Test-Negative Case-Control Analysis Using Surveillance Data.

Background: Despite the disproportionate morbidity and mortality experienced by American Indian and Alaska Native (AI/AN) persons during the coronavirus disease 2019 (COVID-19) pandemic, few studies have reported vaccine effectiveness (VE) estimates among these communities.

Methods: We conducted a test-negative case-control analysis among AI/AN persons aged ≥12 years presenting for care from January 1, 2021, through November 30, 2021, to evaluate the effectiveness of mRNA COVID-19 vaccines against COVID-19-associated outpatient visits and hospitalizations. Cases and controls were patients with ≥1 symptom consistent with COVID-19-like illness; cases were defined as those test-positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and controls were defined as those test-negative for SARS-CoV-2.