Durability and breadth of neutralisation following multiple antigen exposures to SARS-CoV-2 infection and/or COVID-19 vaccination.

Background: Given the importance of vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the prevention of severe coronavirus disease 2019 (COVID-19), detailed long-term analyses of neutralising antibody responses are required to inform immunisation strategies.

Methods: In this study, longitudinal neutralising antibody titres to an ancestral SARS-CoV-2 isolate and cross-neutralisation to delta and omicron isolates were analysed in individuals previously infected with SARS-CoV-2, vaccinated against COVID-19, or a complex mix thereof with up to two years of follow-up.

Findings: Both infection-induced and vaccine-induced neutralising responses against SARS-CoV-2 appeared to follow similar decay patterns.

Novel hepatitis B virus reverse transcriptase mutations in patients with sustained viremia despite long-term tenofovir treatment.

Background: Chronic hepatitis B virus (HBV) treatment consists of nucleos(t)ide analogues to suppress viral replication. The HBV inhibitor tenofovir has a high barrier to resistance, however, evidence of virus-escape is emerging. This study investigates HBV evolution in patients undergoing tenofovir treatment with the primary aim to assess the emergence of putative resistance mutations.

Analysis of Neutralization Titers against SARS-CoV-2 in Health-Care Workers Vaccinated with Prime-Boost mRNA-mRNA or Vector-mRNA COVID-19 Vaccines.

With increasing numbers of vaccine-breakthrough infections worldwide, assessing the immunogenicity of vaccinated health-care workers that are frequently exposed to SARS-CoV-2-infected individuals is important. In this study, neutralization titers against SARS-CoV-2 were assessed one month after completed prime-boost vaccine regimens in health-care workers vaccinated with either mRNA-mRNA (Comirnaty, BioNTech-Pfzier, Mainz, Germany/New York, NY, USA, = 98) or vector-based (Vaxzevria, Oxford-AstraZeneca, Cambridge, UK) followed by mRNA-based (Comirnaty or Spikevax, Moderna, Cambridge, MA, USA) vaccines ( = 16). Vaccine-induced neutralization titers were compared to time-matched, unvaccinated individuals that were infected with SARS-CoV-2 and presented with mild symptoms ( = 38).