Co-Occurrence of Two Plasmids Encoding Transferable and (Y) Genes in Carbapenem-Resistant .

has emerged as a significant human pathogen, acquiring multiple antibiotic resistance genes, including carbapenemases. This study focuses on characterizing the plasmids harboring the and (Y) genes in two carbapenem-resistant isolates (UCO-553 and UCO-554) obtained in Chile during the COVID-19 pandemic. : Antibiotic susceptibility testing was conducted on UCO-553 and UCO-554.

Successful use of daptomycin and cefazolin in a case of persistent bacteremia caused by community acquired-methicillin resistant Staphylococcus aureus in a pregnant woman. Case report.

We present the case of a pregnant woman with community-acquired methicillin-resistant Staphylococcus aureus bacteremia who required combined treatment with daptomycin and cefazolin for control after failure of an initial treatment with vancomycin. She had a favorable evolution, and the study of family contacts revealed a phenotypic and genetically similar isolate in a nasal sample from his mother. The carriage study on three household cats was negative.

SARS-CoV-2 infectivity and antigenic evasion: spotlight on isolated Omicron sub-lineages.

Since the SARS-CoV-2 outbreak in 2019, a diversity of viral genomic variants has emerged and spread globally due to increased transmissibility, pathogenicity, and immune evasion. By the first trimester of 2023 in Chile, as in most countries, BQ and XBB were the predominant circulating sub-lineages of Omicron. The molecular and antigenic characteristics of these variants have been mainly determined using non-authentic spike pseudoviruses, which is often described as a limitation.

Early host immune responses in a human organoid-derived gallbladder monolayer to Typhi strains from patients with acute and chronic infections: a comparative analysis.

serovar Typhi (. Typhi), a human-restricted pathogen, invades the host through the gut to cause typhoid fever. Recent calculations of the typhoid fever burden estimated that more than 10 million new typhoid fever cases occur in low and middle-income countries, resulting in 65,400-187,700 deaths yearly.

Carbapenem-resistant hypervirulent ST23 Klebsiella pneumoniae with a highly transmissible dual-carbapenemase plasmid in Chile.

Background: The convergence of hypervirulence and carbapenem resistance in the bacterial pathogen Klebsiella pneumoniae represents a critical global health concern. Hypervirulent K. pneumoniae (hvKp) strains, frequently from sequence type 23 (ST23) and having a K1 capsule, have been associated with severe community-acquired invasive infections.

Detecting Residual Chronic Salmonella Typhi Carriers on the Road to Typhoid Elimination in Santiago, Chile, 2017-2019.

Background: In Santiago, Chile, where typhoid had been hyperendemic (1977-1991), we investigated whether residual chronic carriers could be detected among household contacts of non-travel-related typhoid cases occurring during 2017-2019.

Methods: Culture-confirmed cases were classified as autochthonous (domestically acquired) versus travel/immigration related. Household contacts of cases had stool cultures and serum Vi antibody measurements to detect chronic Salmonella Typhi carriers.

Humoral immune response in people living with HIV after administration of SARS-CoV-2 vaccine CoronaVac or BNT162b2 or CoronaVac/BNT162b2 booster sequence: A cross-sectional study.

Background: The evidence of SARS-CoV-2 vaccine effectiveness in people living with HIV (PLWH) is limited. This study evaluated the humoral immune response to CoronaVac™ (virus inactivated) and BNT162b2 (mRNA- based) vaccines in PLWH and HIV-negative controls, with and without a booster sequence.

Methods: We conducted a cross-sectional study on PLWH and HIV-negative controls who received CoronaVac or BNT162b2, with a subgroup receiving a CoronaVac/BNT162b2 booster.

Antimicrobial resistance, pathogenic potential, and genomic features of carbapenem-resistant isolated in Chile: high-risk ST25 clones and novel mobile elements.

Multidrug- and carbapenem-resistant (CR-) are critical threats to global health and key traffickers of resistance genes to other pathogens. Despite the sustained increase in CR- infections in Chile, few strains have been described at the genomic level, lacking details of their resistance and virulence determinants and the mobile elements mediating their dissemination. In this work, we studied the antimicrobial susceptibility and performed a comparative genomic analysis of 10 CR- isolates from the Chilean surveillance of carbapenem-resistant .

Global diversity and antimicrobial resistance of typhoid fever pathogens: Insights from a meta-analysis of 13,000 Typhi genomes.

Background: The Global Typhoid Genomics Consortium was established to bring together the typhoid research community to aggregate and analyse serovar Typhi (Typhi) genomic data to inform public health action. This analysis, which marks 22 years since the publication of the first Typhi genome, represents the largest Typhi genome sequence collection to date (n=13,000).

Methods: This is a meta-analysis of global genotype and antimicrobial resistance (AMR) determinants extracted from previously sequenced genome data and analysed using consistent methods implemented in open analysis platforms GenoTyphi and Pathogenwatch.

Factors influencing neutralizing antibody response to the original SARS-CoV-2 virus and the Omicron variant in a high vaccination coverage country, a population-based study.

Unlabelled: The study compared immunity to the original SARS-CoV-2 virus (Wuhan) and the Omicron variant using neutralizing antibodies (NAbs), that provide a good approximation of protective immunity. The results might help determine immunization strategies.

Design And Methods: Unlike previous studies, we analyzed NAbs in a random sample of 110 IgG positive sera from individuals who participated in a population-based seroprevalence transversal study, carried out in May 2022 in two Chilean cities, a country with high vaccination coverage.

Hypervirulent Strains of Neisseria meningitidis and Clinical Manifestations in Children With Invasive Meningococcal Disease.

Background: Hypervirulent clonal complex (cc) have been associated with higher incidence and case fatality rate of invasive meningococcal disease (IMD). The aim of this study was to describe the clinical manifestations of the hypervirulent cc of meningococcus in children.

Methods: Retrospective study in patients hospitalized by IMD microbiologically confirmed at three children's tertiary health care centers in Santiago, Chile, between 2010 and 2018.

A Third Dose of SARS-CoV-2 mRNA Vaccine Improves Immune Response in Chronic Kidney Disease Patients.

Chronic kidney disease (CKD) patients have an increased risk of morbidity and mortality following SARS-CoV-2 infection. Vaccination in these patients is prioritized, and monitoring of the immune response is paramount to define further vaccination strategies. This prospective study included a cohort of 100 adult CKD patients: 48 with kidney transplant (KT) and 52 on hemodialysis without prior COVID-19.

Seroprevalence of Natural and Acquired Immunity against the SARS-CoV-2 Virus in a Population Cohort from Two Chilean Cities, 2020-2022.

Background: Chile has achieved the highest coverage for vaccines against the SARS-CoV-2 virus worldwide.

Objective: To assess the progression of immunity (natural and acquired by vaccine) in a cohort from two Chilean cities.

Methods: Individuals ( = 386) who participated in three phases of population-based serial prevalence studies were included (2020-2021 and 2022).

Increased Detection of Carbapenemase-Producing Enterobacterales Bacteria in Latin America and the Caribbean during the COVID-19 Pandemic.

During 2020-2021, countries in Latin America and the Caribbean reported clinical emergence of carbapenemase-producing Enterobacterales that had not been previously characterized locally, increased prevalence of carbapenemases that had previously been detected, and co-production of multiple carbapenemases in some isolates. These increases were likely fueled by changes related to the COVID-19 pandemic, including empirical antibiotic use for potential COVID-19-related bacterial infections and healthcare limitations resulting from the rapid rise in COVID-19 cases. Strengthening antimicrobial resistance surveillance, epidemiologic research, and infection prevention and control programs and antimicrobial stewardship in clinical settings can help prevent emergence and transmission of carbapenemase-producing Enterobacterales.

Novel Megaplasmid Driving NDM-1-Mediated Carbapenem Resistance in ST1588 in South America.

Carbapenem-resistant Enterobacterales (CRE) is a critical public health problem in South America, where the prevalence of NDM metallo-betalactamases has increased substantially in recent years. In this study, we used whole genome sequencing to characterize a multidrug-resistant (MDR) (UCO-361 strain) clinical isolate from a teaching hospital in Chile. Using long-read (Nanopore) and short-read (Illumina) sequence data, we identified a novel un-typeable megaplasmid (314,976 kb, pNDM-1_UCO-361) carrying the carbapenem resistance gene within a Tn transposon.

Deep immunophenotyping reveals biomarkers of multisystemic inflammatory syndrome in children in a Latin American cohort.

Background: Multisystemic inflammatory syndrome in children (MIS-C) is a life-threatening disease that occurs 2-5 weeks after severe acute respiratory syndrome coronavirus 2 exposure and is characterized by severe multisystemic inflammation. Early recognition of MIS-C is key to prognosis; therefore, establishing clinical and laboratory biomarkers that predict complications is urgently needed.

Objective: We characterized the immune response and clinical features of patients with acute MIS-C and determined biomarkers of disease in a cohort of 42 Latin American patients.

Advances in Integrated Antimicrobial Resistance Surveillance and Control Strategies in Asia-Pacific Economic Cooperation Economies: Assessment of a Multiyear Building Capacity Project.

Antimicrobial resistance (AMR) is a growing global health concern for both animal and public health, and collaborative strategies are needed to combat the threat. The level of awareness and funding for policies focused on reducing AMR varies between countries. The aim of this study was to compare the integrated surveillance systems for AMR in high and low-middle economies of the Asia-Pacific Economic Cooperation and determine whether there was any improvement from 2015 to 2018.

Phenotypic and Genotypic Characterization of Macrolide, Lincosamide and Streptogramin B Resistance among Clinical Methicillin-Resistant Isolates in Chile.

Macrolides, lincosamides, and type B streptogramins (MLSB) are important therapeutic options to treat methicillin-resistant Staphylococcus aureus (MRSA) infections; however, resistance to these antibiotics has been emerging. In Chile, data on the MLSB resistance phenotypes are scarce in both community-(CA) and hospital-acquired (HA) MRSA isolates. Antimicrobial susceptibility to MLSB was determined for sixty-eight non-repetitive isolates of each HA-(32) and CA-MRSA (36).

SARS-CoV-2 Neutralizing Antibodies in Chile after a Vaccination Campaign with Five Different Schemes.

Using levels of neutralizing antibodies (nAbs), we evaluate the successful Chilean SARS-CoV-2 vaccine campaign, which combines different vaccine technologies and heterologous boosters. From a population-based study performed in November 2021, we randomly selected 120 seropositive individuals, organized into six groups of positive samples (20 subjects each) according to natural infection history and the five most frequent vaccination schemes. We conclude that the booster dose, regardless of vaccine technology or natural infection, and mRNA vaccines significantly improve nAbs response.

Immunization and SARS-CoV-2 Antibody Seroprevalence in a Country with High Vaccination Coverage: Lessons from Chile.

Chile is among the most successful nations worldwide in terms of its COVID-19 vaccine rollout. By 31 December 2021, 84.1% of the population was fully vaccinated, and 56.

Evaluation of the Immune Response Induced by CoronaVac 28-Day Schedule Vaccination in a Healthy Population Group.

CoronaVac vaccine from Sinovac Life Science is currently being used in several countries. In Chile, the effectiveness of preventing hospitalization is higher than 80% with a vaccination schedule. However, to date, there are no data about immune response induction or specific memory.

Chaperone mediated autophagy contributes to the newly synthesized histones H3 and H4 quality control.

Although there are several pathways to ensure that proteins are folded properly in the cell, little is known about the molecular mechanisms regulating histone folding and proteostasis. In this work, we identified that chaperone-mediated autophagy (CMA) is the main pathway involved in the degradation of newly synthesized histones H3 and H4. This degradation is finely regulated by the interplay between HSC70 and tNASP, two histone interacting proteins.