We describe clinical and laboratory findings of 3 autochthonous cases of dengue in the Paris Region, France, during September–October 2023. Increasing trends in cases, global warming, and growth of ...international travel mean that such infections likely will increase during warm seasons in France, requiring stronger arbovirus surveillance networks.
The SARS-CoV-2 Omicron variant can escape neutralization by vaccine-elicited and convalescent antibodies. Memory B cells (MBCs) represent another layer of protection against SARS-CoV-2, as they ...persist after infection and vaccination and improve their affinity. Whether MBCs elicited by mRNA vaccines can recognize the Omicron variant remains unclear. We assessed the affinity and neutralization potency against the Omicron variant of several hundred naturally expressed MBC-derived monoclonal IgG antibodies from vaccinated COVID-19-recovered and -naive individuals. Compared with other variants of concern, Omicron evaded recognition by a larger proportion of MBC-derived antibodies, with only 30% retaining high affinity against the Omicron RBD, and the reduction in neutralization potency was even more pronounced. Nonetheless, neutralizing MBC clones could be found in all the analyzed individuals. Therefore, despite the strong immune escape potential of the Omicron variant, these results suggest that the MBC repertoire generated by mRNA vaccines still provides some protection against the Omicron variant in vaccinated individuals.
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•Omicron evaded a large fraction of memory B cell (MBC)-derived antibodies•Only 30% of the MBCs retained high affinity against Omicron•Omicron neutralization by MBCs was reduced even more in all individuals•Neutralizing antibodies still represented more than 10% of the MBC repertoire
Whether memory B cells (MBCs) elicited by SARS-CoV-2 mRNA vaccines can recognize the Omicron variant remains unclear. Sokal et al. show that compared with other variants of concern, Omicron evaded recognition and neutralization by a larger proportion of MBC-derived antibodies elicited after infection and/or vaccination. Nonetheless, Omicron-neutralizing MBC clones could be found in the repertoire of all the analyzed individuals.
•Multiple myeloma patients have poor serological responses after influenza vaccination.•Treatment with daratumumab (anti-CD38) does not seem to further impair such response.•A boosted vaccination ...could have a positive impact on humoral responses.•Future research is needed for innovative prophylaxis strategies in these patients.
Daratumumab-treated myeloma patients may face increased seasonal influenza risk due to weakened postvaccination immune responses, especially with daratumumab treatment. We aimed to assess humoral responses to boosted influenza vaccination in daratumumab-treated or -untreated patients.
In a single-center study, we evaluated humoral responses (hemagglutination-inhibition assay) one month following a two-injection (4-weeks apart) influenza vaccination (standard dose) in 84 patients with multiple myeloma (40 with daratumumab in the past year).
Seroprotection rates (titer ≥1/40) after the second vaccine injection were low across vaccinal subtypes (except for A-H3N2): 71.3% (A-H3N2), 19.7% (A-H1N1pdm09), 9.9% (B-Victoria), 11.3% (B-Yamagata). Only A-H3N2 seroprotection rates significantly increased with the booster in daratumumab-treated patients (30% (12/40) after one injection vs 55% (22/40) after the boost; P = 0.01).After propensity score weighting, daratumumab was not significantly associated with a reduced likelihood of seroprotection against at least one vaccine strain (OR 0.65 95% CI: 0.22-1.88).
While daratumumab treatment did not lead to a significant reduction in seroprotection rates following influenza vaccination, a booster vaccine injection demonstrated potential benefit for specific strains (A-H3N2) in patients undergoing daratumumab treatment. Nevertheless, the overall low response rates in patients with multiple myeloma necessitates the development of alternative vaccination and prophylaxis strategies.
Respiratory tract infections (RTIs) are a leading cause of death after kidney transplant. Preventive strategies may be implemented during a dedicated infectious disease consultation (IDC) before ...transplantation. Impact of IDC on RTIs after transplant has not been determined.
We conducted a monocentric retrospective cohort analysis including all kidney transplant recipients from January 2015 to December 2019. We evaluated the impact of IDC on RTIs and identified risk and protective factors associated with RTIs.
We included 516 kidney transplant recipients. Among these, 145 had an IDC before transplant. Ninety-five patients presented 123 RTIs, including 75 (61%) with pneumonia. Patient that benefited from IDC presented significantly less RTIs (
= 0.049). RTIs were an independent risk factor of mortality (HR = 3.64 (1.97-6.73)). Independent risk factors for RTIs included HIV (OR = 3.33 (1.43-7.74)) and HCV (OR = 3.76 (1.58-8.96)). IDC was identified as an independent protective factor (OR = 0.48 (0.26-0.88)). IDC prior to transplantation is associated with diminished RTIs and is an independent protective factor. RTIs after kidney transplant are an independent risk factor of death. Implementing systematic IDC may have an important impact on reducing RTIs and related morbidity and mortality.
SARS-CoV-2 mRNA vaccination generates protective B cell responses targeting the SARS-CoV-2 spike glycoprotein. Whereas anti-spike memory B cell responses are long lasting, the anti-spike humoral ...antibody response progressively wanes, making booster vaccinations necessary for maintaining protective immunity. Here, we qualitatively investigated the plasmablast responses by measuring from single cells within hours of sampling the affinity of their secreted antibody for the SARS-CoV-2 spike receptor binding domain (RBD) in cohorts of BNT162b2-vaccinated naive and COVID-19-recovered individuals. Using a droplet microfluidic and imaging approach, we analyzed more than 4,000 single IgG-secreting cells, revealing high interindividual variability in affinity for RBD, with variations over 4 logs. High-affinity plasmablasts were induced by BNT162b2 vaccination against Hu-1 and Omicron RBD but disappeared quickly thereafter, whereas low-affinity plasmablasts represented more than 65% of the plasmablast response at all time points. Our droplet-based method thus proves efficient at fast and qualitative immune monitoring and should be helpful for optimization of vaccination protocols.
Epidemiology of opportunistic infections (OI) after kidney allograft transplantation in the modern era of immunosuppression and the use of OI prevention strategies are poorly described. We ...retrospectively analyzed a single-center cohort on kidney allograft adult recipients transplanted between January 2008 and December 2013. The control group included all kidney recipients transplanted in the same period, but with no OI. We analyzed 538 kidney transplantations (538 patients). The proportion of OI was 15% (80 and 72 patients). OI occurred 12.8 (6.0-31.2) months after transplantation. Viruses were the leading cause (
= 54, (10%)), followed by fungal (
= 15 (3%)), parasitic (
= 6 (1%)), and bacterial (
= 5 (0.9%)) infections. Independent risk factors for OI were extended criteria donor (2.53 (1.48-4.31),
= 0.0007) and BK viremia (6.38 (3.62-11.23),
< 0.0001). High blood lymphocyte count at the time of transplantation was an independent protective factor (0.60 (0.38-0.94),
= 0.026). OI was an independent risk factor for allograft loss (2.53 (1.29-4.95),
= 0.007) but not for patient survival. Post-kidney transplantation OIs were mostly viral and occurred beyond one year after transplantation. Pre-transplantation lymphopenia and extended criteria donor are independent risk factors for OI, unlike induction therapy, hence the need to adjust immunosuppressive regimens to such transplant candidates.
Vaso-occlusive crisis (VOC), hallmark of sickle-cell disease (SCD), is the first cause of patients' Emergency-Room admissions and hospitalizations. Acute chest syndrome (ACS), a life-threatening ...complication, can occur during VOC, be fatal and prolong hospitalization. No predictive factor identifies VOC patients who will develop secondary ACS.
This prospective, monocenter, observational study on SS/S-β0thalassemia SCD adults aimed to identify parameters predicting ACS at Emergency-Department arrival. The primary endpoint was ACS onset within 15days of admission. Secondary endpoints were hospitalization duration, morphine consumption, pain evaluation, blood transfusion(s) (BT(s)), requiring intensive care and mortality.
Among 250 VOCs included, 247 were analyzed. Forty-four (17.8%) ACSs occurred within 15 (median IQR 3 2, 3) days post-admission based on auscultation abnormalities; missing chest radiographs excluded three patients. Comparing ACS to VOC, respectively, median hospital stay was longer 9 7–11 vs 4 3–7 days (p<0.0001), 7/41 (17%) vs 1/203 (0.5%) required intensive care (p<0.0001), and 20/41 (48.7%) vs 6/203 (3%) required BTs (p<0.0001). No patient died. The multivariate model retained reticulocyte and leukocyte counts, and spine and/or pelvis pain as being independently associated with ACS; the resulting ACS-predictive score's area under the ROC was 0.840 95% CI 0.780–0.900, 98.8% negative-predictive value and 39.5% positive-predictive value for the real ACS incidence.
The ACS-predictive score is simple, easily applied and could change VOC management and therapeutic perspectives. Assessed ACS risk could lead to earlier discharges or close monitoring and rapid medical intensification to prevent ACS.
•Acute chest syndrome is a threatening complication.•Acute chest syndrome often occurs during a vaso occlusive crisis.•Our study provides a predictive score of acute chest syndrome.
Acute chest syndrome (ACS) is a major complication of sickle-cell disease. Bacterial infection is one cause of ACS, so current guidelines recommend the routine use of antibiotics. We performed a ...prospective before–after study in medical wards and an intensive-care unit (ICU). During the control phase, clinicians were blinded to procalcitonin concentration results. We built an algorithm using the obtained measurements to hasten antibiotic cessation after three days of treatment if bacterial infection was not documented, and procalcitonin concentrations were all <0.5 μg/L. During the intervention period, the procalcitonin algorithm was suggested to physicians as a guide for antibiotic therapy. The primary endpoint was the number of days alive without antibiotics at Day 21. One-hundred patients were analyzed (103 ACS episodes, 60 in intervention phase). Possible or proven lung infection was diagnosed during 13% of all ACS episodes. The number of days alive without antibiotics at Day 21 was higher during the intervention phase: 15 14–18 vs. 13 13,14 days (p = 0.001). More patients had a short (≤3 days) antibiotic course during intervention phase: 31% vs 9% (p = 0.01). There was neither infection relapse nor pulmonary superinfection in the entire cohort. A procalcitonin-guided strategy to prescribe antibiotics in patients with ACS may reduce antibiotic exposure with no apparent adverse outcomes.
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