Complete Genome Characterization of Eight Human Parainfluenza Viruses from the Netherlands.

We report the complete genome sequences of eight human parainfluenza viruses (HPIV) belonging to Human respirovirus 1 (HPIV-1), Human respirovirus 3 (HPIV-3), Human rubulavirus 2 (HPIV-2), and Human rubulavirus 4 (HPIV-4). The genome sequences were generated using random-primed next-generation sequencing and represent the first HPIV full-genome sequences from the Netherlands

Clearance of influenza virus from the lung depends on migratory langerin+CD11b− but not plasmacytoid dendritic cells

Although dendritic cells (DCs) play an important role in mediating protection against influenza virus, the precise role of lung DC subsets, such as CD11b− and CD11b+ conventional DCs or plasmacytoid DCs (pDCs), in different lung compartments is currently unknown. Early after intranasal infection, tracheal CD11b−CD11chi DCs migrated to the mediastinal lymph nodes (MLNs), acquiring co-stimulatory molecules in the process. This emigration from the lung was followed by an accumulation of CD11b+CD11chi DCs in the trachea and lung interstitium. In the MLNs, the CD11b+ DCs contained abundant viral nucleoprotein (NP), but these cells failed to present antigen to CD4 or CD8 T cells, whereas resident CD11b−CD8α+ DCs presented to CD8 cells, and migratory CD11b−CD8α− DCs presented to CD4 and CD8 T cells. When lung CD11chi DCs and macrophages or langerin+CD11b−CD11chi DCs were depleted using either CD11c–diphtheria toxin receptor (DTR) or langerin-DTR mice, the development of virus-specific CD8+ T cells was severely delayed, which correlated with increased clinical severity and a delayed viral clearance. 120G8+ CD11cint pDCs also accumulated in the lung and LNs carrying viral NP, but in their absence, there was no effect on viral clearance or clinical severity. Rather, in pDC-depleted mice, there was a reduction in antiviral antibody production after lung clearance of the virus. This suggests that multiple DCs are endowed with different tasks in mediating protection against influenza virus

Brain stem encephalitis is a rare complication of COVID-19

Here, we describe the clinical phenotype of SARS-CoV-2-related CNS disease and evaluate the SARS-CoV-2 antibody index as a tool to differentiate between a direct (viral) and indirect etiology. Out of >4000 hospitalized patients with COVID-19, we included 13 patients with neurological symptoms with suspicion of neuroinflammation. On clinical grounds, eight were classified as having a possible/probable relationship between neurological symptoms and COVID-19. A clinically distinctive phenotype of brainstem and cerebellar symptoms was seen in 6/8 patients. As we found a positive SARS-CoV-2 antibody index in 3/5 patients, indicating specific intrathecal SARS-CoV-2 IgG production, a direct link with SARS-CoV-2 is likely

Immunogenicity of a bivalent Omicron BA.1 COVID-19 booster vaccination in people with HIV in the Netherlands

Objective We evaluated the immunogenicity of a bivalent BA.1 COVID-19 booster vaccine in people with HIV (PWH). Design Prospective observational cohort study. Methods PWH aged ≥45 years received Wuhan-BA.1 mRNA-1273.214 and those < 45 years Wuhan-BA.1 BNT162b2. Participants were propensity score-matched 1:2 to people without HIV (non-PWH) by age, primary vaccine platform (mRNA-based or vector-based), number of prior COVID-19 boosters and SARS-CoV-2 infections, and spike (S1)-specific antibodies on the day of booster administration. The primary endpoint was the geometric mean ratio (GMR) of ancestral S1-specific antibodies from day 0 to 28 in PWH compared to non-PWH. Secondary endpoints included humoral responses, T-cell responses, and cytokine responses up to 180 days post-vaccination. Results Forty PWH received mRNA-1273.214 (N = 35) or BNT162b2 (N = 5) following mRNA-based (N = 29) or vector-based (N = 11) primary vaccination. PWH were predominantly male (87% vs 26% of non-PWH) and median 57 years (interquartile range [IQR] 53–59). Their median CD4+ T-cell count was 775 (IQR 511–965) and the plasma HIV-RNA load was < 50 copies/mL in 39/40. The GMR of S1-specific antibodies by 28 days post-vaccination was comparable between PWH (4.48, 95% confidence interval [CI] 3.24–6.19) and non-PWH (4.07, 95% CI 3.42–4.83). S1-specific antibody responses were comparable between PWH and non-PWH up to 180 days, and T-cell responses up to 90 days post-vaccination. IFN-γ, IL-2, and IL-4 cytokine concentrations increased 28 days post-vaccination in PWH. Conclusion A bivalent BA.1 booster vaccine was immunogenic in well-treated PWH, eliciting comparable humoral responses to non-PWH. However, T-cell responses waned faster after 90 days in PWH compared to non-PWH

Primary Exposure to SARS-CoV-2 via Infection or Vaccination Determines Mucosal Antibody-Dependent ACE2 Binding Inhibition

Background: Mucosal antibodies play a critical role in preventing SARS-CoV-2 infections or reinfections by blocking the interaction of the receptor-binding domain (RBD) with the angiotensin-converting enzyme 2 (ACE2) receptor on the cell surface. In this study, we investigated the difference between the mucosal antibody response after primary infection and vaccination. Methods: We assessed longitudinal changes in the quantity and capacity of nasal antibodies to neutralize the interaction of RBD with the ACE2 receptor using the spike protein and RBD from ancestral SARS-CoV-2 (Wuhan-Hu-1), as well as the RBD from the Delta and Omicron variants. Results: Significantly higher mucosal IgA concentrations were detected postinfection vs postvaccination, while vaccination induced higher IgG concentrations. However, ACE2-inhibiting activity did not differ between the cohorts. Regarding whether IgA or IgG drove ACE2 inhibition, infection-induced binding inhibition was driven by both isotypes, while postvaccination binding inhibition was mainly driven by IgG. Conclusions: Our study provides new insights into the relationship between antibody isotypes and neutralization by using a sensitive and high-Throughput ACE2 binding inhibition assay. Key differences are highlighted between vaccination and infection at the mucosal level, showing that despite differences in the response quantity, postinfection and postvaccination ACE2 binding inhibition capacity did not differ.</p

Immunogenicity of a bivalent Omicron BA.1 COVID-19 booster vaccination in people with HIV in the Netherlands

Objective We evaluated the immunogenicity of a bivalent BA.1 COVID-19 booster vaccine in people with HIV (PWH). Design Prospective observational cohort study. Methods PWH aged ≥45 years received Wuhan-BA.1 mRNA-1273.214 and those &lt; 45 years Wuhan-BA.1 BNT162b2. Participants were propensity score-matched 1:2 to people without HIV (non-PWH) by age, primary vaccine platform (mRNA-based or vector-based), number of prior COVID-19 boosters and SARS-CoV-2 infections, and spike (S1)-specific antibodies on the day of booster administration. The primary endpoint was the geometric mean ratio (GMR) of ancestral S1-specific antibodies from day 0 to 28 in PWH compared to non-PWH. Secondary endpoints included humoral responses, T-cell responses, and cytokine responses up to 180 days post-vaccination. Results Forty PWH received mRNA-1273.214 (N = 35) or BNT162b2 (N = 5) following mRNA-based (N = 29) or vector-based (N = 11) primary vaccination. PWH were predominantly male (87% vs 26% of non-PWH) and median 57 years (interquartile range [IQR] 53–59). Their median CD4+ T-cell count was 775 (IQR 511–965) and the plasma HIV-RNA load was &lt; 50 copies/mL in 39/40. The GMR of S1-specific antibodies by 28 days post-vaccination was comparable between PWH (4.48, 95% confidence interval [CI] 3.24–6.19) and non-PWH (4.07, 95% CI 3.42–4.83). S1-specific antibody responses were comparable between PWH and non-PWH up to 180 days, and T-cell responses up to 90 days post-vaccination. IFN-γ, IL-2, and IL-4 cytokine concentrations increased 28 days post-vaccination in PWH. Conclusion A bivalent BA.1 booster vaccine was immunogenic in well-treated PWH, eliciting comparable humoral responses to non-PWH. However, T-cell responses waned faster after 90 days in PWH compared to non-PWH

Orthopoxvirus-specific antibodies wane to undetectable levels 1 year after MVA-BN vaccination of at-risk individuals, the Netherlands, 2022 to 2023

In response to the mpox outbreak in 2022 and 2023, widespread vaccination with modified vaccinia Ankara-Bavarian Nordic (MVA-BN, also known as JYNNEOS or Imvanex) was initiated. Here, we demonstrate that orthopoxvirus-specific binding and MVA-neutralising antibodies waned to undetectable levels 1 year post vaccination in at-risk individuals who received two doses of MVA-BN administered subcutaneously with an interval of 4 weeks, without prior smallpox or mpox vaccination. Continuous surveillance is essential to understand the impact of declining antibody levels.</p

Timing and sequence of vaccination against COVID-19 and influenza (TACTIC):a single-blind, placebo-controlled randomized clinical trial

Background: Novel mRNA-based vaccines have been used to protect against SARS-CoV-2, especially in vulnerable populations who also receive an annual influenza vaccination. The TACTIC study investigated potential immune interference between the mRNA COVID-19 booster vaccine and the quadrivalent influenza vaccine, and determined if concurrent administration would have effects on safety or immunogenicity. Methods: TACTIC was a single-blind, placebo-controlled randomized clinical trial conducted at the Radboud University Medical Centre, the Netherlands. Individuals ≥60 years, fully vaccinated against COVID-19 were eligible for participation and randomized into one of four study groups: 1) 0.5 ml influenza vaccination Vaxigrip Tetra followed by 0.3 ml BNT162b2 COVID-19 booster vaccination 21 days later, (2) COVID-19 booster vaccination followed by influenza vaccination, (3) influenza vaccination concurrent with the COVID-19 booster vaccination, and (4) COVID-19 booster vaccination only (reference group). Primary outcome was the geometric mean concentration (GMC) of IgG against the spike (S)-protein of the SARS-CoV-2 virus, 21 days after booster vaccination. We performed a non-inferiority analysis of concurrent administration compared to booster vaccines alone with a predefined non-inferiority margin of −0.3 on the log10-scale. Findings: 154 individuals participated from October, 4, 2021, until November, 5, 2021. Anti-S IgG GMCs for the co-administration and reference group were 1684 BAU/ml and 2435 BAU/ml, respectively. Concurrent vaccination did not meet the criteria for non-inferiority (estimate −0.1791, 95% CI −0.3680 to −0.009831) and antibodies showed significantly lower neutralization capacity compared to the reference group. Reported side-effects were mild and did not differ between study groups. Interpretation: Concurrent administration of both vaccines is safe, but the quantitative and functional antibody responses were marginally lower compared to booster vaccination alone. Lower protection against COVID-19 with concurrent administration of COVID-19 and influenza vaccination cannot be excluded, although additional larger studies would be required to confirm this. Trial registration number: EudraCT: 2021-002186-17 Funding: The study was supported by the ZonMw COVID-19 Programme.</p