Serial infection with SARS-CoV-2 Omicron BA.1 and BA.2 following three-dose COVID-19 vaccination

Abstract

SARS-CoV-2 Omicron infections are common among individuals who are vaccinated or have recovered from prior variant infection, but few reports have documented serial Omicron infections. We characterized SARS-CoV-2 humoral responses in a healthy young person who acquired laboratory-confirmed Omicron BA.1.15 ten weeks after a third dose of BNT162b2, and BA.2 thirteen weeks later. Responses were compared to those of 124 COVID-19 naive vaccinees. One month after the second and third vaccine doses, the participant’s wild-type and BA.1-specific IgG, ACE2 competition and virus neutralization activities were average for a COVID-19 naive triple-vaccinated individual. BA.1 infection boosted the participant’s responses to the cohort ≥95th percentile, but even this strong “hybrid” immunity failed to protect against BA.2. Moreover, reinfection increased BA.1 and BA.2-specific responses only modestly. Results illustrate the risk of Omicron infection in fully vaccinated individuals and highlight the importance of personal and public health measures as vaccine-induced immune responses wane.

The prevalence of SARS-CoV-2 infection and other public health outcomes during the BA.2/BA.2.12.1 surge, New York City, April-May 2022

“…Rather, because of recent prior BA.1 infection among a wide swath of the NYC adult population, it may be that those re-infected with BA.2/BA.2.12.1 after a recent BA.1 infection had a lower mean peak viral load due to greater acquired T-cell mediated immunity from prior BA.1 infection. [35][36][37] This could effectively reduce the magnitude of peak SARS-CoV-2 concentration in wastewater, even for roughly the same number of individuals in the population with active SARS-CoV-2 infection. If this is true, it would suggest that wastewater surveillance may be less useful for surge detection soon after a recent widespread surge like BA.1, and requires further investigation.…”

Immunogenicity of COVID-19 vaccines and their effect on the HIV reservoir in older people with HIV

“…Only a few studies have analysed immune responses in PWH following three doses of COVID-19 vaccines, although initial reports on individuals with preserved CD4 + T cell count are optimistic (54). In our study of cART-treated PWH in the older age group, we showed that each COVID-19 vaccine dose, regardless of its type, induces binding IgG Abs for spike and RBD in plasma and spike IgG in saliva at levels similar in PWH and age-matched HIV-negative individuals.…”