This study assessed the transmission, prevalence and genomic characteristics of carbapenem-resistant Acinetobacter Baumannii (CARB) isolated from object surfaces and healthcare workers' hands in seven hospitals of Shanghai in 2019 (pre-COVID pandemic) and 2023 (post-COVID pandemic). CRAB isolates were tested for antimicrobial susceptibility using the broth microdilution method and whole-genome sequencing. Antimicrobial resistance genes, Multilocus Sequence Typing (MLST), polysaccharide capsule and plasmid migration were evaluated based on tools such as VFDB database, PubMLST, Kaptive, MOB-suite, etc. RESULTS: Of 3,156 samples collected, 130 strains of CRAB were isolated. The prevalence of CRAB in the ICU setting was significantly lower in 2023 (2.44%) than in 2019 (5.60%). Objects that come into direct contact with patients served as a primary source (43.85%). CRAB isolates exhibited higher resistance to β-lactamase antibiotics but lower to minocycline (2.31%), tigecycline (3.08%) and polymyxin B (2.31%). Five ST_Pasteur and eleven ST_Oxford were identified, predominantly ST2_Pasteur (93.6%) and ST208_Oxford (40%). Two novel sequence types (STs) named ST3329 and ST3331 were found in the surface of objects such as door handles. Notably, two CARB isolates (designated 2023-AB023 and 2023-AB033) co-harboring the bla_OXA-23, bla_OXA-91, bla_NDM-1 were found to be high genomic similarity to DETAB-R21 previously isolated from an ICU patient's oral swab with high environmental adaptability, reported in August 2022 in Zhejiang Province of China. The resistance rate of CRAB was slightly lower in 2023 compared to 2019. However, the emergence of pan-drug-resistant CRAB, along with the coexistence of carbapenemase-producing strains (OXA-23, OXA-51-like, and NDM-1) in 2023, underscore the dynamic progression of antimicrobial resistance (AMR) in this pathogen. These findings suggest a potential epidemiological shift characterized by clonal diversification alongside persistent carbapenemase-driven resistance mechanisms.

This study aimed to assess the risk of acute respiratory infections across distinct age demographics, analyze factors associated with infection, and characterize respiratory pathogen epidemiology in the post-COVID-19 era. We conducted this longitudinal community-based surveillance study in Pudong New Area from November 2023 to January 2024. Questionnaires were designed to assess acute respiratory infection (ARI) incidence, and respiratory pathogens were detected among qualified patients with ARI. Pathogenic features were compared and analyzed among different age groups. A total of 6698 participants were included and completed the study. The overall ARI incidence was 2.55 (95% CI 2.42-2.68) per 1000 person-days. The incidence of ARI progressively decreased with increasing age. The factors significantly associated with infection were sex, employment, and chronic conditions among participants who reported symptoms. Influenza virus, Haemophilus influenzae, human rhinovirus, and human coronavirus were the most commonly detected viruses. The positive distribution rate was similar among all age groups. The influenza virus trend maintained a prolonged peak period. The incidence of ARI exhibited a progressive decline with advancing age. Community-based surveillance identifies respiratory pathogen profiles during early or mild infections, complementing routine surveillance.

Background: Carbapenem-resistant Acinetobacter baumannii (CRAB) is priority pathogen for nosocomial infection control worldwide. This study aimed to elucidate differences in distribution, genotyping and antimicrobial resistance patterns between CRAB and carbapenem-susceptible Acinetobacter baumannii (CSAB) strains isolated from healthcare environments. Materials and methods: A total of 1,812 environmental samples were collected from 10 medical institutions in Pudong New Area between June and December 2024 for the identification of A. baumannii . Antimicrobial susceptibility testing, whole-genome sequencing, and bioinformatic analysis were performed to reveal molecular characteristics of A. baumannii. Results: A total of 81 A. baumannii strains were detected, with 39.51% CRAB ( n = 32) and 60.49% CSAB ( n = 49). CRAB strains were highly prevalent in intensive care units (ICUs, accounting for 83.33%) and patient-contact items, whereas CSAB were more evenly distributed. MLST analysis identified ST2 as dominant CRAB clone (78.13%), followed by ST164 (18.75%). CRAB isolates demonstrated 100% resistance to multiple antibiotics such as piperacillin/tazobactam and ciprofloxacin, whereas all CSAB isolates were susceptible to tested antibiotics except one ampicillin/sulbactam-resistant isolate. Carbapenem resistance in CRAB was predominantly mediated by class D carbapenemases, with carriage rate of the bla _OXA-23 gene reaching 96.88%. Notably, six ST164 isolates co-harbored class B and class D carbapenemase genes, which may elevate resistance severity. Bioinformatic analysis indicated that 22.20% of resistance plasmids in CRAB were predicted to be conjugative. CRAB exhibited a more diverse and extensive virulence gene profile than CSAB strains. Conclusions: The ICU environment was critical for CRAB control. ST2 and ST164 represented clones worthy of attention. CRAB exhibited stronger resistance, harbored more putatively conjugative plasmids and richer virulence-associated genes than CSAB, highlighting the need for targeted disinfection and surveillance of prevalent clones.

Introduction: Historically, human infections with clade Ia monkeypox virus (MPXV) primarily occurred through zoonotic transmission with limited secondary human-to-human transmission. Recent studies suggest increasing evidence of human-to-human transmission of some clade Ia lineages. This report documents the first imported clade Ia mpox case in Shanghai, representing the second documented case in China. Methods: Patient demographics, clinical profiles, epidemiological history, and close contacts were obtained through interviews with the patient and attending physicians. Clinical specimens were collected for real-time fluorescent quantitative polymerase chain reaction (qPCR) and whole-genome sequencing. Contact tracing was implemented, involving a 21-day health monitoring of close contacts. Results: The patient presented with moderate symptoms, including fever, rash, and respiratory manifestations. Genome sequencing identified the virus as clade Ia, showing 99.96% nucleotide identity to a strain from the Democratic Republic of Congo (DRC). Eight close contacts were identified with no secondary infection reported. Conclusions: This case was confirmed as an imported clade Ia mpox case originating in the DRC. The “four JOINTs” cross-agency collaborative mechanism between the CDC and customs played a significant role in effectively stopping local transmission. Challenges in remote investigation highlight the need for stronger international collaboration. Establishing an integrated “early warning-control-tracking” system, coupled with public health intervention, is crucial for reducing importation risks and safeguarding national health security.