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Objectives: The aim of this study was to investigate the prevalence of ceftazidime/avibactam (CZA) resistance among carbapenemase-producing Enterobacterales (CPE) blood culture isolates as well as the performance of the main carbapenemase phenotypic detection methods to identify KPC variants associated with CZA resistance. Methods: Non-duplicate CPE strains isolated from blood cultures during 2018–2020 were tested for antimicrobial susceptibility. Molecular testing was used to identify carbapenemase-producers. Strains harbouring blaKPC and with a CZA minimum inhibitory concentration (MIC) ≥8 mg/L were investigated by sequencing. Subsequentially, five phenotypic carbapenemase detection methods were evaluated on these strains, namely the modified carbapenem inactivation method (mCIM), Rapidec® Carba NP, the disk diffusion synergy test, NG-Test CARBA® 5 and RESIST-5 O.O.K.N.V. Results: Overall, the CZA resistance rate was high (13.7%) and remained relevant (5.9%) excluding metallo-β-lactamases-producers. All isolates harbouringblaKPC mutants (n = 8) were associated with reduced carbapenem MICs and negative results by all detection methods based on revelation of enzyme activity. Lateral flow immunoassays failed to detect KPC-31 (n = 4) and KPC-33 (n = 2) but correctly identified KPC-14 (n = 2). Conversely, isolates harbouring wild-type KPC genes (n = 3) were associated with high-level CZA resistance and carbapenem resistance and tested positive by all of the evaluated methods. Conclusion: In the era of CZA-based therapies, molecular blaKPC identification followed by a carbapenem hydrolysis-based phenotypic assay could be the most reasonable diagnostic algorithm to detect all KPC-producers and to identify mutants associated with impaired carbapenemase activity and CZA resistance.

Voluntary termination of pregnancy (VTP), pre-conception and post-partum phases, as well as Occupational Medicine consultation for healthcare workers are opportunities for screening and vaccinating rubella seronegative childbearing women. However, data about vaccination acceptance following these phases is rarely reported.A retrospective study over a 2-year period (2016–2017) was performed, evaluating the prevalence of rubella seronegative women which underwent VTP (wVTP), mothers in early puerperal phase (mEPP) and childbearing healthcare workers (CbHW) aged 15–49 years. Anti-rubella vaccination rates and factors associated with vaccine hesitancy (VH) were investigated.Anti-rubella IgG titres were assessed in 8623 women. Seroprevalence of rubella susceptibility was 7.9% (wVTP 6.4%; mEPP 17.4%; CbHW 9.3%). Anti-rubella vaccination rates were found to be different in the three groups (wVTP 37.1%; mEPP 10.9%; CbHW 25.4%), specifically in 2016 and among women born in Italy. VH rate was higher in 2017, especially among wVTP and CbHW. Anti-rubella vaccination rates in wVTP vs. mEPP was higher in women born in Italy but not in those born abroad. Multivariable analyses demonstrated significantly higher risk of VH for mEPP (OR 8.2; 95% CI: 3.9–16.9) and women reporting history of allergy to drugs, food or environmental agents (OR 2.7; 95% CI: 1.4–5.1).During the analyzed period childbearing women included in this study were not adequately protected against rubella. Anti-rubella vaccination rates were widely unsatisfactory. Being mEPP and reporting allergy were significantly associated to higher rates of VH. Tailored strategies targeting on vaccine safety are needed for retention of these women in immunisation programmes. Keywords: Rubella, Congenital rubella syndrome, Vaccination