Inanimate Surfaces and Air Contamination with Multidrug Resistant Species of Staphylococcus in the Neonatal Intensive Care Unit Environment

Coagulase-Negative Staphylococci Determined as Blood Culture Contamination Have High Virulence Characteristic Including Transfer of Antibiotic Resistance Determinants to Staphylococcus aureus and Escherichia coli

This study aimed to evaluate the virulence of 36 clinical isolates estimated as blood culture contaminants (BCCs). MALDI-TOF MS classified all isolates as coagulase-negative staphylococci (CoNS) with the highest percentage of S. epidermidis (77.78%). All tested strains formed biofilms with greater ability at room temperature than 37 °C. CoNS were sensitive to vancomycin (0% resistance) and had relatively low resistance to linezolid and rifampicin (8.33 and 22.22% resistance). The highest resistance was observed for penicillin (94.44%). Moreover, we observed the transfer of antibiotic resistance genes from the tested CoNS to S. aureus and even to E. coli, although with lower efficiency. CoNS in planktonic form were completely combated by antiseptics after 10 and 60 s exposition, and activity against biofilms was time-dependent. The complete elimination of biofilms was observed after a 180 s exposure to Kodan and CITROclorex, and this exposure to Rivanol and Octenidyne showed still viable cells (>0.9 log CFU/mL). Our findings showed that a careful selection of antiseptics and extending the exposure time before blood collection can reduce the occurrence of blood culture contamination. However, our most important finding is the indication that CoNS naturally occurring on human skin and mucous membranes exhibit antibiotic resistance, and what is more, determinants of antibiotic resistance are transferred to both closely related Gram-positive bacteria and phylogenetically distant Gram-negative bacteria. Thus, our findings shed new light on CoNS-they indicate the necessity of their control due to the effective transfer of mobile genetic elements harboring antibiotic resistance genes, which may contribute to the spread of resistance genes and deepening the antibiotic crisis.

Evolving patterns of healthcare-associated infections in NICU: a five-year retrospective analysis from a tertiary children's hospital in China

BACKGROUND

Neonates in the NICU, particularly those born with very low birth weights, are at heightened risk for healthcare-associated infections (HAIs). Such infections can prolong hospitalization, increase medical costs, and potentially lead to adverse long-term outcomes. Recognizing evolving infection patterns and targeted prevention measures is essential to improving patient care.

METHODS

We retrospectively collected data on neonates admitted to the NICU of our hospital between January 2019 and December 2023. Information regarding HAI incidence, site of infection, device utilization, pathogen distribution, and antibiotic use was extracted and statistically analyzed. Comparisons regarding infection rates and clinical variables were performed using chi-square or Fisher's exact tests for categorical variables and Wilcoxon rank-sum tests for continuous variables.

RESULTS

Among 9786 neonates (70,509 patient-days), 86 HAI cases were identified (0.88%), corresponding to 1.22‰ infections per 1000 patient-days. Neonates with extremely low birth weight had significantly higher infection rates (13.04%) than other birth weight groups (p < 0.01). Bloodstream infections (35.87%) were the most common site, followed by respiratory and gastrointestinal infections (both 18.48%). Central line-associated bloodstream infection occurred at 0.75 infections per 1000 catheter-days, while ventilator-associated pneumonia decreased from 2.76‰ to 0.73‰ over the study period. Staphylococcus epidermidis was the predominant isolate among the pathogens identified. Neonates with HAIs had significantly longer antibiotic courses and higher rates of combination antibiotic therapy (p < 0.001).

CONCLUSIONS

Although the overall incidence of NICU HAIs declined from 2019 to 2023, infection patterns continued to evolve, particularly regarding bloodstream infections. Prevention strategies must focus on high-risk neonates, rigorous device management, punctual surveillance of pathogen resistance, and prudent antibiotic use to further reduce infection morbidity and mortality in the NICU setting.

Oxacillin-resistant Staphylococcus spp.: Impacts on fatality in a NICU in Brazil - confronting the perfect storm

OBJECTIVE

Analyse the incidence, risk factors, antimicrobial susceptibility profile, and fatality in neonates infected with oxacillin-resistant Staphylococcus spp. (ORS).

METHODS

In this retrospective observational descriptive cohort study, the medical records of neonates admitted to the Neonatal Intensive Care Unit (NICU) from January 2015 to June 2022 were analysed. Participants were monitored daily through the National Healthcare Safety Network.

RESULTS

Among the 1610 neonates, 193 (12 %) developed ORS infections, primarily in the bloodstream (96.8 %). The incidence of these infections/patient-days decreased by 51.8 % between 2016 (8.3) and 2022 (4). The median age of affected neonates was 17.5 days (IQR:12-28.7). Pre-emptive prescription of fourth-generation cephalosporins (OR=14.36; P<0.01) emerged as a risk factor in the multivariate analysis. Staphylococcus epidermidis was the most prevalent species (60.1 %), with one isolate showing a "susceptible, increased exposure" profile to vancomycin. Additionally, 2 % of pathogens were extensively drug-resistant (XDR). ORS infections were associated with prolonged hospital stays (from 10 to 46 days) and increased mortality (from 10.2 % to 19.2 %). The median time between infection and the fatal outcome was 15 days (IQR:8-40), and Staphylococcus capitis was the most lethal species (26.7 %).

CONCLUSIONS

The high incidence of ORS infections was linked to extended hospitalisation and increased mortality, highlighting the complexity of this situation - a "perfect storm." This underscores the urgency of implementing effective interventions for managing and preventing ORS infections in the NICU.

Antimicrobial properties of hindered amine light stabilizers in polymer coating materials and their mechanism of action

UV-stabilizers are a class of additives that provide extended polymer resistance to UV-degradation, but have also been suggested to have antimicrobial activity, potentially preventing the spread of pathogens, and inhibiting microbial-induced biodegradation. In this work, we incorporated different UV-stabilizers, a hindered amine light stabilizer (HALS), Tinuvin 770 DF and Tinuvin PA 123, or a hybrid HALS/UV-absorber, Tinuvin 5151, in polyurethane formulations to produce lacquer-films, and tested their antimicrobial activity against Staphylococcus aureus (methicillin-resistant and -sensitive strains), Escherichia coli and Candida albicans. Lacquer-films incorporated with Tinuvin 770 DF showed strong antimicrobial performance against bacteria and fungi, while maintaining cytocompatibility. The mechanism of action revealed a positive relationship between Tinuvin 770 DF concentration, microbial death, and reactive nitrogen species (RNS), suggesting that RNS produced during autoxidation of Tinuvin 770 DF is responsible for the antimicrobial properties of this UV-stabilizer. Conversely, lacquer-films incorporated with Tinuvin 5151 or Tinuvin PA 123 exhibited no antimicrobial properties. Collectively, these results highlight the commercial potential of Tinuvin 770 DF to prevent photo- and biodegradation of polymers, while also inhibiting the spread of potentially harmful pathogens. Furthermore, we provide a better understanding of the mechanism underlying the biocidal activity of HALS associated to autooxidation of the amine group.

Molecular distribution of biocide resistance genes and susceptibility to biocides among vancomycin resistant Staphylococcus aureus (VRSA) isolates from intensive care unit (ICU) of cardiac hospital- A first report from Pakistan

BACKGROUND

The study was conducted with the aim to investigate the VRSA isolates in terms of their susceptibility to routinely used biocides influenced by the co-occurrence of biocide resistant gene (BRGs) and efflux pumps genes.

METHODOLOGY

Frequently touched surfaces within intensive care unit (ICU) of cardiac hospital were classified into three primary sites i.e., structure, machines and miscellaneous. Over a period of six months (January 2021 to July 2021) twenty three swabs samples were collected from these sites. Subsequently, these samples underwent both phenotypic and molecular methods for VRSA isolation and identification. Susceptibility and efficacy testing of biocides (benzalkonium chloride (BAC), cetrimide (CET) and chlorhexidine gluconate (CHG)) were evaluated using microdilution broth and suspension method. Furthermore, specific primers were used for singleplex PCR targeting BRGs (cepA, qacA, and qacE) and efflux pump (norA, norB, norC, sepA, mepA and mdeA) associated genes.

RESULTS

We found that 72.2 % S. aureus demonstrate the presence of vanA or vanB genes with no significant difference among three sites (p > 0.05). cepA is the most dominant BRGs followed by qacA and qacE from structure site as compared to other sites (p < 0.05). BAC showed reduced biocide susceptibility and MIC50. There was no significant difference between presence or absence of BRGs and high MIC values of VRSA isolates from all three sites. However, efflux pump genes (EFPGs) particularly norA and norA + sepA had a significant association with BRGs and reduced biocide.

CONCLUSION

BAC is the most effective disinfectant against VRSA. Proper and controlled use of BAC is required to overcome the VRSA contamination. We recommend continuous monitoring of the BRGs prevalence for better prevention of microorganism dissemination and infection control in hospitals.