Journal of medical microbiology最新文献

For thousands of years, parasitic infections have represented a constant challenge to human health. Despite constant progress in science and medicine, the challenge has remained mostly unchanged over the years, partly due to the vast complexity of the host-parasite-environment relationships. Over the last century, our approaches to these challenges have evolved through considerable advances in science and technology, offering new and better solutions. Unfortunately, in the twenty-first century, this diagnostic evolution was suddenly confronted with a dramatic change of biological relationships, never witnessed in history before the uncontrolled expansion of the human population, globalization and hyperconnectivity technology have exerted a massive socioeconomic impact on individuals, communities and the environment, sending a ripple effect throughout the world of parasites. Urbanization, pollution and the unsustainable exploitation of natural resources have caused shifts in biomass and the fragmentation of habitats, leading to the movement of parasites into new hosts and territories. At the same time, changes in human population structure and distributions due to armed conflict and poverty created massive migration of entire nations and communities, resulting in the redistribution of parasitic diseases. To make the situation worse, the population of many receiving countries of North America and Europe is ageing, leading to a critical shortage of a specialized workforce essential to deal with the new diagnostic challenges. Unfortunately, this vicious circle is not yet apparent to all. The highly specialized field of parasitology is at a particular risk for such major crises in the near future. Heightened awareness of such risks is an essential step to start discussions and planning to mitigate these very real health threats.

Leptospirosis is a re-emerging zoonosis caused by a diverse range of pathogenic Leptospira, which are divided into species, serogroups and serovars. Although advances in genomics have recently refined species classification, serotyping, which is based on the antigenic variability of lipopolysaccharides O-antigens, still relies heavily on traditional and labour-intensive methods. In addition, the molecular basis of serovar diversity is not fully understood, which poses challenges for rapid and accurate serovar and/or serogroup identification. However, identification of serovars remains crucial for epidemiological studies, surveillance, diagnostics, understanding host-pathogen interactions and vaccine development. In this review, we assess current techniques for Leptospira serovar and serogroup identification and explore emerging DNA-based methodologies for serovar and serogroup prediction.

Introduction. Sputum is the most used sample type to monitor the lower respiratory tract microbiota in cystic fibrosis (CF), but young patients often cannot expectorate.Hypothesis. We hypothesized that throat swabs could reflect lower airway colonization and assessed the concordance of bacterial community composition between paired sputum and throat swab samples from children with CF.Aim. We aimed to compare bacterial community diversity and composition between sputum and throat swabs in the full cohort and in patients with paired samples from the same visit.Methodology. The prospective longitudinal multicentre MUCOVIB cohort included 379 samples from 61 CF children. Using V3-V4 16S rRNA amplicon metagenomics, we compared bacterial community diversity and composition between sputum and throat swabs in the full cohort and in 11 patients with paired samples from the same visit.Results. Sputum and throat swabs exhibited similar bacterial diversity, regardless of the exacerbation status, and presented a substantial agreement for detecting pathogens (Cohen's kappa: 0.6). Differences in bacterial abundance were observed (P=0.001), but not presence/absence (P=0.098). Community typing revealed three distinct community types, with 86% of paired samples falling into the same cluster, highlighting the homogeneity between sputum and throat swab microbiota. Network analysis demonstrated slight, non-random similarities in microbial interactions between sample types (adjusted Rand index=0.08 and 0.10). The average beta-diversity distances between samples collected from the same visit were shorter (0.505±0.056 95% confidence interval), compared with sputum (0.695±0.017) or throat swab (0.704±0.045) from the same patient collected during different visits.Conclusion. Throat swabs can provide representative information on lower respiratory microbiota. Clinicians should collect throat swabs rather than relying on sputum samples from previous visits to guide antibiotic prescriptions in CF children unable to expectorate.

Introduction. Infection is a leading cause of mortality during the first year of life, with the neonatal period being particularly high risk. It is critical to identify non-antibiotic approaches to improve neonatal infection outcomes due to the non-specific clinical signs of neonatal infection and negative consequences of early-life antibiotic exposure. Lactoferrin is a protein found in all mammalian milk that has a variety of antimicrobial properties. Clinical trials have shown that lactoferrin supplementation during the neonatal period decreases rates of sepsis.Knowledge Gap. It remains unclear if there is an optimal lactoferrin preparation for human neonates.Aim. Compare bacterial growth inhibition capabilities between different commercially available bovine-derived lactoferrin (bLF) preparations.Methodology. This study uses a broth microdilution in vitro assay to directly compare the antibacterial effects and shelf stability of different bLF preparations against three common neonatal pathogens: Escherichia coli, Klebsiella pneumoniae and Streptococcus pneumoniae.Results. Bacterial growth inhibition differed significantly between bLF manufacturers and between different bLF lots/batches from the same manufacturer. Approximately half of the bLF products demonstrated decreased bacterial growth inhibition capabilities within 7-14 days after solubilization.Conclusion. These findings may help select optimal bLF products for clinical use in the neonatal population, but additional in vivo studies are needed to confirm our in vitro findings.

Background. Achromobacter xylosoxidans and Pseudomonas aeruginosa are two pathogens that cause persistent airway infections in individuals with cystic fibrosis (CF). The persistence of P. aeruginosa is partly due to a high capacity to form biofilms and the ability to exert antagonism against other bacteria. Loss of microbial diversity in conjunction with chronic P. aeruginosa colonization is strongly correlated with low lung function in CF. A. xylosoxidans and P. aeruginosa are frequently co-isolated in CF airway cultures. This study aims to investigate the reciprocal effects on growth inhibition and biofilm formation between P. aeruginosa and A. xylosoxidans in vitro.Method. Six isolates of A. xylosoxidans, isolated from three CF patients in early and late stages of a chronic infection, were cultured together with a CF isolate of P. aeruginosa. Biofilm formation was assessed using a microtiter assay and crystal violet staining. Quantitative PCR was used to quantify species proportions in biofilms. Growth curves were performed to compare planktonic growth rates.Results. Three A. xylosoxidans isolates, all of which were from early-stage infections, inhibited biofilm formation of P. aeruginosa. The inhibition was concentration-dependent and required the interaction of live bacteria during the early stages of biofilm development. The inhibitory effect was not caused by nutrient depletion of the planktonic cells. The selected A. xylosoxidans isolate had a stronger capacity to adhere to plastic surfaces compared to the P. aeruginosa isolate.Conclusions . A. xylosoxidans can inhibit P. aeruginosa biofilm formation in vitro. The observed effect requires active interactions between live cells during the attachment stage of biofilm formation, possibly due to differences in adhesion capacity.

Introduction . Campylobacter jejuni is the leading cause of bacterial gastroenteritis worldwide. Infections with C. jejuni can result in two different diarrhoeal manifestations in humans: watery diarrhoea or bloody/inflammatory diarrhoea.Hypothesis/Gap Statement. Currently, little is known about C. jejuni and/or host factors associated with the elicitation of these two distinct diarrhoeal manifestations. We hypothesize that these factors may include growth and metabolic trait differences between C. jejuni strains associated with watery diarrhoea and bloody/inflammatory diarrhoea.Aim. Using C. jejuni strains with a defined diarrhoeal manifestation in the neonatal piglet model, we aimed to assess differences in temperature-dependent growth rates, motility, biofilm production and carbon utilization between diarrhoeal manifestation groups.Methodology. Strains were initially assessed for 192 different carbon sources using phenotypic microarrays followed by specific carbon utilization, growth, motility and biofilm assays at 37 and/or 42 °C.Results. We found that at 37 °C, watery diarrhoea-associated C. jejuni strains grew significantly faster compared with bloody/inflammatory diarrhoea-associated C. jejuni strains. However, there was no significant growth difference at 42 °C between the groups, due to bloody/inflammatory diarrhoea-associated strains growing faster at 42 °C compared with 37 °C. Additionally, at 37 °C, we found that l-fucose utilization was significantly higher among watery diarrhoea-associated strains, while l-glutamine utilization was significantly higher among bloody/inflammatory diarrhoea-associated strains.Conclusion. The results indicate there are distinct metabolic adaptations between watery and/or bloody/inflammatory diarrhoea-associated C. jejuni strains particularly at 37 °C, which may be one of the factors associated with differing diarrhoeal manifestations.

The COVID-19 pandemic has significantly increased the complexity of managing burn patients, who are particularly susceptible to bacterial co-infections due to their compromised skin barriers and immune dysregulation. Toxin-producing bacteria, such as Staphylococcus aureus and Pseudomonas aeruginosa, pose severe risks by producing virulence factors that impair immune function, delay wound healing and exacerbate systemic inflammation. These challenges are amplified in the presence of SARS-CoV-2, as the viral-induced immune dysregulation and cytokine storms worsen clinical outcomes, leading to higher rates of morbidity and mortality. This review explores the interplay between viral and bacterial infections in burn patients during the COVID-19 pandemic, focusing on the role of bacterial toxins, including superantigens from S. aureus and exotoxins from P. aeruginosa in driving hyperinflammatory responses. These synergistic effects complicate treatment by increasing the likelihood of systemic complications, prolonged hospital stays and MDR infections. To address these challenges, we discuss innovative therapeutic strategies, including endotoxin adsorption therapy to reduce systemic inflammation, immunomodulatory treatments to control cytokine storms and bacteriophage therapy for targeting MDR pathogens. Advanced wound care techniques and rapid diagnostic tools, such as CRISPR-based molecular assays, are highlighted as essential for timely and effective intervention. This review underscores the urgent need for integrated approaches that combine targeted diagnostics, advanced therapeutics and robust infection control measures. These insights aim to improve outcomes for burn patients co-infected with bacterial pathogens and SARS-CoV-2, offering valuable guidance for future pandemic preparedness and burn care protocols.

Antimicrobial resistance (AMR) is a real and current threat to public health, yet the role of vaccines in combating this crisis remains underutilized and under-recognized. This meeting report summarizes key insights from a multidisciplinary workshop convened by the Microbiology Society in February 2025, as part of the Knocking Out AMR initiative, bringing together 21 expert stakeholders across academia, industry, clinical and veterinary sectors and policy. The workshop explored how vaccines can reduce the burden of AMR by preventing infections, limiting antibiotic use and slowing resistance development. Discussions highlighted the need to strengthen the evidence base for vaccine-mediated AMR reduction, address policy and regulatory barriers and incentivize public-private collaboration in vaccine development. Participants called for AMR impact to be formally recognized in vaccine labelling and national immunization strategies, and for greater integration of vaccines into AMR action plans. The workshop also underscored the importance of One Health approaches, investment in research for both human and animal vaccines and the role of the microbiology community in driving change.