Meningococcal carriage in men who have sex with men presenting at a sexual health unit in Spain.

Neisseria meningitidis (Nm) is asymptomatically carried in the nasopharynx of 5-10% adults, although certain populations, such as men who have sex with men (MSM), exhibit a higher colonisation rate. Interest in Nm carriage has been renewed, owed to meningitis outbreaks within populations of MSM. The aim of this study was to characterise Nm isolates and risk factors for its carriage among MSM attending a sexual health unit. A retrospective cross-sectional study was undertaken between June 2018 and December 2021. We took anal, oropharyngeal, urethral, and blood samples as part of the sexually transmitted infection screening procedures routinely implemented. Nm isolates were subjected to antimicrobial susceptibility testing; the serogroup and genogroup were determined by multi-locus sequence typing. A total of 399 subjects were recruited, and the Nm oropharyngeal carriage rate was 29%, similar among both people living with HIV (PLWH) and uninfected individuals. Nm carriage was less common in vaccinated individuals, especially those who had received the tetravalent vaccine (2.6% vs. 10.6%, p = 0.008). The most frequent serogroups were B (40%) and non-groupable (45%). Most of the isolates were susceptible to ciprofloxacin (96%) and ceftriaxone (100%). However, we identified 21 strains (20%) belonging to hyperinvasive lineages (CC11, CC4821, CC32, CC41/44, CC213, and CC269), most of which belonged to serogroup B. Given that vaccination with MenACWY was associated with a low Nm carriage, we encourage routine vaccination of all MSM. Moreover, the administration of the meningitis B vaccine should also be assessed considering that several invasive lines included in serogroup B are circulating among MSM.

In vivo monitoring of Lactiplantibacillus plantarum in the nasal and vaginal mucosa using infrared fluorescence.

Lactic acid bacteria (LAB) of the genus Lactiplantibacillus have been explored as potential mucosal vaccine vectors due to their ability to elicit an immune response against expressed foreign antigens and to their safety. However, tools for monitoring LAB distribution and persistence at the mucosal surfaces are needed. Here, we characterize Lactiplantibacillus plantarum bacteria expressing the infrared fluorescent protein IRFP713 for exploring their in vivo distribution in the mucosa and potential use as a mucosal vaccine vector. This bacterial species is commonly used as a vaginal probiotic and was recently found to have a niche in the human nose. Three different fluorescent L. plantarum strains were obtained using the nisin-inducible pNZRK-IRFP713 plasmid which contains the nisRK genes, showing stable and constitutive expression of IRFP713 in vitro. One of these strains was further monitored in BALB/c mice using near-infrared fluorescence, indicating successful colonization of the nasal and vaginal mucosae for up to 72 h. This study thus provides a tool for the in vivo spatiotemporal monitoring of lactiplantibacilli, allowing non-invasive bacterial detection in these mucosal sites. KEY POINTS: • Stable and constitutive expression of the IRFP713 protein was obtained in different L. plantarum strains. • IRFP713+ L. plantarum 3.12.1 was monitored in vivo using near-infrared fluorescence. • Residence times observed after intranasal and vaginal inoculation were 24-72 h.

Silver Nanoparticles Produced by Laser Ablation and Re-Irradiation Are Effective Preventing Peri-Implantitis Multispecies Biofilm Formation.

Implant-associated infection due to biofilm formation is a growing problem. Given that silver nanoparticles (Ag-NPs) have shown antibacterial effects, our goal is to study their effect against multispecies biofilm involved in the development of peri-implantitis. To this purpose, Ag-NPs were synthesized by laser ablation in de-ionized water using two different lasers, leading to the production of colloidal suspensions. Subsequently, part of each suspension was subjected to irradiation one and three times with the same laser source with which it was obtained. Ag-NPs were immobilized on the surface of titanium discs and the resultant materials were compared with unmodified titanium coupons. Nanoparticles were physico-chemically analysed to determine their shape, crystallinity, chemical composition, and mean diameter. The materials were incubated for 90 min or 48 h, to evaluate bacterial adhesion or biofilm formation respectively with Staphylococcus aureus or oral mixed bacterial flora composed of Streptococcus oralis, Actinomyces naeslundii, Veionella dispar, and Porphyromonas gingivalis. Ag-NPs help prevent the formation of biofilms both by S. aureus and by mixed oral bacterial flora. Nanoparticles re-irradiated three times showed the biggest antimicrobial effects. Modifying dental implants in this way could prevent the development of peri-implantitis.

Antimicrobial resistance, virulence factors and genetic lineages of hospital-onset methicillin-resistant Staphylococcus aureus isolates detected in a hospital in Zaragoza.

INTRODUCTION: MRSA population dynamics is undergoing significant changes, and for this reason it is important to know which clones are circulating in our nosocomial environment. MATERIALS AND METHODS: A total of 118 MRSA isolates were collected from clinical samples from patients with previous hospital or healthcare contact (named as hospital-onset MRSA (HO-MRSA)) during a one year period. Susceptibility testing was performed by disk diffusion and microdilution. The presence of resistance genes and virulence factors were tested by PCR. All isolates were typed by SCCmec, spa and agr typing. PFGE and MLST were applied to a selection of them. RESULTS: Eighty-three HO-MRSA isolates (70.3%) were resistant to any antibiotic included in the macrolide-lincosamide-streptogramin B group. Among these isolates, the M phenotype was the most frequent (73.5%). One hundred and seven of HO-MRSA isolates (90.7%) showed aminoglycoside resistance. The combination aac(6')-Ie-aph(2″)-Ia+ant(4')-Ia genes was the most frequent (22.4%). Tetracycline resistance rates in HO-MRSA isolates were low (3.4%), although a high level of mupirocin resistance was observed (25.4%). Most of the HO-MRSA isolates (approximately 90%) showed SCCmec type IVc and agr type II. Fifteen unrelated pulsotypes were identified. CC5 was the most prevalent (88.1%), followed by CC8 (5.9%), CC22 (2.5%), CC398 (2.5%) and CC1 (0.8%). CONCLUSION: CC5/ST125/t067 lineage was the most frequent. This lineage was related to aminoglycoside resistance, and to a lesser extent, with macrolide resistance. The presence of international clones as EMRSA-15 (CC22/ST22), European clones as CC5/ST228, community clones related to CC1 or CC8 and livestock associated clones, as CC398, were observed in a low percentage.

Usefulness of PCR-RFLP coa gene for clonal classification of methicillin-resistant Staphylococcus aureus isolates in tertiary hospitals.

One hundred and one methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates were classified into 10 genotypes based on their polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) coa pattern. PCR-RFLP coa patterns correlated with the clonal complex (CC) with the exception of CC5, which was related to 2 patterns (B and E). The PCR-RFLP coa gene technique provides a useful preliminary method to monitor variations in MRSA populations.

Large Increase in Azithromycin-Resistant Neisseria gonorrhoeae in Northern Spain.

The aim of this study was to characterize the evolution of gonorrhea in the general population by correlating epidemiological, genotypic, and antimicrobial resistance data of Neisseria gonorrhoeae isolates collected in northern Spain from 2014 to 2018. One hundred ninety-four strains underwent antimicrobial susceptibility testing and were genetically analyzed by N. gonorrhoeae multiantigen sequence typing. Increasing cases of gonococcal infections have been observed after 2015. Most occurred in male with urethritis. Sequence type (ST)-9972 and ST-1576, the predominant genotypes identified, have not been previously described as epidemic clones. Of great concern was the significant increase in azithromycin-resistant N. gonorrhoeae. More than 30% of these isolates were obtained from men who have sex with men (MSM). ST-12302 was the most prevalent clone among the azithromycin-resistant strains, and was also resistant to penicillin, ciprofloxacin, and tetracycline. This multidrug-resistant clone was exclusively isolated from MSM during 2018. The incidence rates of gonorrhea and azithromycin-resistant N. gonorrhoeae have significantly increased due to the emergence of new clones. ST-12302 has recently been recognized as an epidemic clone; therefore, its surveillance could be the key in controlling further dissemination of azithromycin resistance. These data highlight the need to perform local studies to update treatment guidelines and reinforce preventive measures against gonorrhea.

Real-life cohort experience after implementing HIV pre-exposure prophylaxis for one year in northwest Spain.

Introduction: Pre-exposure prophylaxis (PrEP) has become a useful tool to reduce the transmission of human immunodeficiency virus (HIV) in key populations. In this article we assessed the effectiveness, safety, adherence, sexually transmitted infections (STIs) dynamics, and frequency of anal dysplasia among a real-life cohort of PrEP users in Northwest Spain. Methods: A retrospective cohort study was undertaken in the Alvaro-Cunqueiro Hospital, Vigo which included every individual who started daily emtricitabine/tenofovir-disoproxil-fumarate (FTC/TDF) between November-2019 and October-2021. Clinical and epidemiological data were obtained from the patient's medical records. The effectiveness and safety of FTC/TDF were assessed by HIV serology and renal function monitoring every 3 months. Anal, urethral, and oropharyngeal exudates were collected quarterly after the baseline visit. Results: A total of 126 individuals were considered eligible, most of the participants had previously been diagnosed with a STI (60.3%), 22% had consumed recreational drugs in the year prior, and 13% had engaged in chemsex. At the end of the follow-up, no cases of HIV infection were detected; 3 patients had discontinued FTC/TDF because of side effects but none of them had presented renal toxicity. In addition, the diagnosis of STIs during the follow-up was common (100 cases in 54 patients). Moreover, engagement in chemsex was more common within this latter group (22 vs. 6%, p = 0.013). Among the study population included in the anal screening programme, the frequency of dysplasia was 9%. Conclusions: FTC/TDF was effective, safe, and tolerable in a real-life cohort; adherence remained high throughout the study period (79%). However, a high number of STIs were diagnosed, especially among patients who engaged in chemsex.

Genotypic and phenotypic characterization of methicillin-resistant Staphylococcus aureus (MRSA) clones with high-level mupirocin resistance.

A high proportion of methicillin-resistant Staphylococcus aureus isolates recovered in one year period showed high-level mupirocin-resistance (HLMUPR-MRSA) in our environment (27.2%). HLMUPR-MRSA isolates were mainly collected from skin and soft tissue samples, and diabetes was the main related comorbidity condition. These isolates were more frequently found in vascular surgery. HLMUPR-MRSA was more resistant to aminoglycosides than mupirocin-susceptible MRSA, linked to the presence of bifunctional and/or nucleotidyltransferase enzymes with/without macrolide resistance associated with the msr(A) gene. Most of HLMUPR-MRSA isolates belonged to ST125/t067. Nine IS257-ileS2 amplification patterns (p3 was the most frequent) were observed in HLMUPR-MRSA isolates, suggesting the presence of several mupirocin-resistance-carrying plasmids in our environment and promoting the emergence of mupirocin resistance. The presence of the same IS257-ileS2 amplification pattern p3 in 65% of HLMUPR-MRSA, all of them ST125/t067, suggests a clonal spread in our hospital and community environment which could explain the high prevalence of HLMUPR-MRSA during the study period. An outbreak situation or an increase in mupirocin consumption was not observed.