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Background Maternal priming with the Bacille Calmette-Guérin (BCG) vaccine has been associated with reduced offspring mortality rates. We investigated this association in a cohort of frail neonates. Methods We performed an observational study within a randomized BCG trial conducted at the neonatal intensive care unit (NICU) in Guinea-Bissau from 2015 to 2017. At NICU admission and after informed consent, the maternal scar status was evaluated by visual inspection before neonates were randomized 1:1 to receive BCG + oral polio vaccine immediately or at hospital discharge. Stratified by maternal scar status, we assessed overall in-hospital and postdischarge mortality rates through 42 days of age in Cox proportional hazards models providing adjusted mortality rate ratios (aMRRs). Results Overall, 62% of mothers (903 of 1451) had a BCG vaccine scar. During NICU admission, the mortality risk was 1.7% (15 of 903) for neonates born to mothers with a scar versus 3.3% (18 of 548) for those born to mothers with no scar; the aMRR for maternal scar versus no scar was 0.53 (95% CI,.26–1.05), 0.39 (95% CI,.13–1.05) for unvaccinated and 0.70 (95% CI,.26–1.87) for vaccinated neonates. Conclusions This small study indicates that maternal BCG vaccine might be associated with reduced all-cause NICU mortality rate. If confirmed elsewhere, this finding would have substantial ramifications for global health. [ABSTRACT FROM AUTHOR]

Background: Randomized controlled trials (RCTs) indicate that bacille Calmette-Guérin (BCG) vaccination provides broad beneficial "nonspecific" protection against infections. We investigated the effect on in-hospital mortality of providing BCG immediately upon admission to a neonatal intensive care unit (NICU), rather than BCG-at-discharge. The pretrial NICU mortality was 13% and we hypothesized that BCG would reduce mortality by 40%.Methods: Parallel-group, open-label RCT was initiated in 2013 in Guinea-Bissau. Neonatal intensive care unit-admitted neonates were randomized 1:1 to BCG + oral polio vaccine (OPV) immediately (intervention) versus BCG + OPV at hospital discharge (control; usual practice). The trial was discontinued due to decreasing in-hospital mortality and major NICU restructuring. We assessed overall and disease-specific mortality by randomization allocation in cox proportional hazards models providing mortality rate ratios (MRRs).Results: We recruited 3353 neonates, and the overall mortality was 3.1% (52 of 1676) for BCG-vaccinated neonates versus 3.3% (55 of 1677) for controls (MRR = 0.94; 0.64-1.36). For noninfectious causes of death, the MRR was 1.20 (0.70-2.07), and there tended to be fewer deaths from infections in the BCG group (N = 14) than among controls (N = 21) (MRR = 0.65; 0.33-1.28).Conclusions: Providing BCG + OPV to frail neonates was safe and might protect against fatal infection in the immediate newborn period. Deaths due to prematurity and perinatal complications were unaffected by BCG. [ABSTRACT FROM AUTHOR]

Background: BCG vaccination is associated with a reduction in all-cause infant mortality in high-mortality settings. The underlying mechanisms remain uncertain, but long-term modulation of the innate immune response (trained immunity) may be involved.Methods: Whole-blood specimens, collected 7 days after randomization from 212 neonates enrolled in a randomized trial of neonatal BCG vaccination, were stimulated with killed pathogens and Toll-like receptor (TLR) ligands to interrogate cytokine responses.Results: BCG-vaccinated infants had increased production of interleukin 6 (IL-6) in unstimulated samples and decreased production of interleukin 1 receptor antagonist, IL-6, and IL-10 and the chemokines macrophage inflammatory protein 1α (MIP-1α), MIP-1β, and monocyte chemoattractant protein 1 (MCP-1) following stimulation with peptidoglycan (TLR2) and R848 (TLR7/8). BCG-vaccinated infants also had decreased MCP-1 responses following stimulation with heterologous pathogens. Sex and maternal BCG vaccination status interacted with neonatal BCG vaccination.Conclusions: Neonatal BCG vaccination influences cytokine responses to TLR ligands and heterologous pathogens. This effect is characterized by decreased antiinflammatory cytokine and chemokine responses in the context of higher levels of IL-6 in unstimulated samples. This supports the hypothesis that BCG vaccination modulates the innate immune system. Further research is warranted to determine whether there is an association between these findings and the beneficial nonspecific (heterologous) effects of BCG vaccine on all-cause mortality. [ABSTRACT FROM AUTHOR]

Background. The decline in influenza vaccine efficacy in older adults is associated with a limited ability of current split-virus vaccines (SVVs) to stimulate cytotoxic T lymphocyte (CTL) responses required for clinical protection against influenza. Methods. The Toll-like receptor 4 agonist glucopyranosyl lipid adjuvant-stable emulsion (GLA-SE) was combined with SVV to stimulate peripheral blood mononuclear cells (PBMCs) in vitro to determine the cytokine response in dendritic cell subsets. Stimulated PBMCs were then challenged with live influenza virus to mimic the response to natural infection following vaccination, using previously identified T-cell correlates of protection. Results. GLA-SE significantly increased the proportion of myeloid dendritic cells that produced tumor necrosis factor &agr;, interleukin 6, and interleukin 12. When combined with SVV to stimulate PBMCs in vitro, this effect of GLA-SE was shown to regulate a T-helper 1 cell response upon challenge with live influenza virus; interleukin 10 production was suppressed, thus significantly increasing the interferon &bgr; to interleukin 10 ratio and the cytolytic (granzyme B) response to influenza virus challenge, both of which have been shown to correlate with protection against influenza in older adults. Conclusions. Our findings suggest that a novel adjuvant, GLA-SE, combined with standard SVV has the potential to significantly improve vaccine-mediated protection against influenza in older adults. [ABSTRACT FROM AUTHOR]

Modified, human immunodeficiency virus (HIV)-inoculated thy/liv-SCID-hu mice were used to evaluate the in vivo efficacy of antiretroviral drugs. Ritonavir treatment alone initially suppressed plasma viremia, but the viremia recurred with the appearance of ritonavir-resistant HIV isolates. Multidrug therapy suppressed plasma HIV RNA to undetectable levels; however, plasma viremia returned after therapy was stopped, showing that the therapy did not completely suppress HIV infection in the thymic implant. When thy/liv-SCID-hu mice were treated with a combination of zidovudine, lamivudine, and ritonavir immediately after inoculation with HIV, cocultures of the thymic implants remained negative for HIV even 1 month after therapy was discontinued, suggesting that acute treatment can prevent the establishment of HIV infection. Thus, these modified thy/liv- SCID-hu mice should prove to be a useful system for evaluating the effectiveness of different antiretroviral therapies on acute and chronic HIV infection. [ABSTRACT FROM PUBLISHER]

In this article, the author discusses the issue of neonatal deaths and also mentions use of bacillus Calmette-Guérin (BCG) vaccination in low-birth weight (LBW) infants to tackle neonatal infection. Topics discussed include reduction of neonatal mortality, cytokine response in LBW infants, and change of innate immune status following BCG vaccination.