Aim. Pregnant women require different nutritional intake such as folic acid, iron and cholecalciferol, and specific vaccination to prevent fetal abnormalities and improve outcomes.. This study aims to analyze usage trends for these recommended drugs over the last decade, and to identify maternal factors associated with their use. Methods. The nationwide cross-sectional study is based on data from the French national administrative health database, including pregnancies from 2012 to 2022. Folic acid, iron, cholecalciferol, and influenza vaccination use were analyzed according to the relevant periods based on WHO and French guidelines. Multivariable logistic regression assessed maternal characteristics associated with drug use. Results. Analyzing 8,979,173 pregnancies, the study found that 46.0% of pregnancies used folic acid during the periconceptional period, rising from 33.8% in 2012 to 52.6% in 2022. Women with chronic disease and higher financial resources were more likely to use it. 64.1% used iron during pregnancy with exposure increasing with age. 35.5% used cholecalciferol, with higher socioeconomic status associated with increased use. Only 5.1% were vaccinated against influenza, with the rate increasing until 2020, before declining. Vaccination was positively associated with maternal age, the presence of a chronic disease, and higher financial resources. Conclusion. This study revealed increasing trends of use in recommended drugs during pregnancy over the last decade, although overall prevalence remains not optimal, and concerning for influenza vaccination. The identified risk factors for non-use include young maternal age, low income, and deprived areas, emphasizing the need for targeted interventions to improve maternal health outcomes.

Aim: Population pharmacokinetics (PK) models may be effective to improve antibiotic exposure with individualized dosing. The aim of the study is to assess cefazolin exposure using a population PK model in critically ill children. Methods: We conducted a single center observational study including children under 18 years old who had cefazolin plasma monitoring before and after the model implementation. First concentration at steady state of each cefazolin course was analyzed. Optimal exposure was defined by concentrations values ranged from free concentration over 4 times the MIC for 100% of the dosing interval to total trough or plateau concentration under 100 mg/L. Results: Fifty-eight patients were included, of whom 39 and 19 children received conventional dosing or model-informed dosing, respectively. Median [range] age was 2.3 [0.1-17] years old and median weight was 14.2 [2.9-72] kg. There were more continuous infusions (CI) in the model group than in the conventional group (n=19/19 (100%) vs n=23/39 (59%)). Compared to conventional dosing, model-informed dosing provided more optimal exposure (n=17/39 (44%) vs n= 15/19 (79%), p=0.01) and less underexposure (n= 18/39 (46%) vs n= 2/19 (10%), p=0.008), without increasing overexposure (n= 4/39 (10%) vs n= 2/19 (11%), p=1). Moreover, the time to reach a 50% decrease of C Reactive Protein levels was significantly shorter in the model group than the conventional group (3 [0.5-13] vs 4 [1-34]; p=0.045. Conclusions: Use of individualized cefazolin model-informed dosing improves critically ill children’s exposure. Further studies are needed to assess the clinical benefit of cefazolin PK model application.

Several cases of herpes zoster (HZ) following mRNA COVID-19 vaccination (BNT162b2 and mRNA-1273) have been reported, and first epidemiological evidences suggest an increased risk. We used the worldwide pharmacovigilance database VigiBase to describe HZ cases following mRNA COVID-19 vaccination. We performed disproportionality analyses (case/non-case statistical approach) to assess the relative risk of HZ reporting in mRNA COVID-19 vaccine recipients compared to influenza vaccine recipients and according to patient age. Until 30th June 2021, of 716,928 reports about mRNA COVID-19 vaccines, we found 7,728 HZ cases. When compared to influenza vaccines, mRNA COVID-19 vaccines were associated with a significantly higher reporting of HZ (reporting odds-ratio 1.9, 95%CI [1.8-2.1]). Furthermore, we found a reduced risk of reporting HZ among under 40 year-old persons compared to older persons (reporting odds-ratio 0.39, 95%CI [0.36-0.41]). For the first time, we could assess at a global level the risk of HZ after mRNA COVID-19 vaccination.