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The pharyngeal mucosa can be colonized with bacteria that have potential to cause pharyngotonsillitis. By the use of culturing techniques and PCR, we aimed to assess the prevalence of bacterial pharyngeal pathogens among healthy adolescents and young adults. We performed a cross-sectional study in a community-based cohort of 217 healthy individuals between 16 and 25 years of age. Samples were analyzed for Group A streptococci (GAS), Group C/G streptococci (SDSE), Fusobacterium necrophorum, and Arcanobacterium haemolyticum. Compared to culturing, the PCR method resulted in more frequent detection, albeit in most cases with low levels of DNA, of GAS (20/217 vs. 5/217; p < 0.01) and F. necrophorum (20/217 vs. 8/217; p < 0.01). Culturing and PCR yielded similar rates of SDSE detection (14/217 vs. 12/217; p = 0.73). Arcanobacterium haemolyticum was rarely detected (3/217), and only by PCR. Overall, in 25.3% (55/217) of these healthy adolescents and young adults at least one of these pathogens was detected, a rate that is higher than previously described. Further studies are needed before clinical adoption of PCR-based detection methods for pharyngeal bacterial pathogens, as our findings suggest a high incidence of asymptomatic carriage among adolescents and young adults without throat infections.

Aim: Vaccine‐preventable pathogens causing severe childhood infections include Haemophilus influenzae type b (Hib), Streptococcus pneumoniae and Neisseria meningitidis. In this study conducted in a Swedish Arctic region, we evaluated the effects of general infant Hib and pneumococcal vaccination on invasive infectious diseases among children and assessed the need of meningococcal vaccination.

Methods: We identified cases of bacterial meningitis and sepsis from diagnosis and laboratory registers in the Västerbotten Region, Sweden, during 1986–2015. We then reviewed medical records to confirm the diagnosis and extract data for assessing incidence changes, using an exploratory data analysis and a time‐series analysis.

Results: Invasive Haemophilus disease declined by 89.1% (p < 0.01), Haemophilus meningitis by 95.3% (p < 0.01) and all‐cause bacterial meningitis by 82.3% (p < 0.01) in children aged 0 to four years following general infant Hib vaccination. Following pneumococcal vaccination, invasive pneumococcal disease declined by 84.7% (p < 0.01), pneumococcal meningitis by 67.5% (p = 0.16) and all‐cause bacterial meningitis by 48.0% (p = 0.23). Incidence of invasive meningococcal disease remained low during the study period.

Conclusion: Remarkable sustained long‐term declines of invasive infectious diseases in younger children occurred following infant Hib and pneumococcal vaccinations in this Swedish Arctic region. Despite not offering general infant meningococcal vaccination, incidence of invasive meningococcal disease remained low.

Conclusions Patients with symptomatic perforations of the nasal septum had a high prevalence of S. aureus in the nasal mucosa. Pulsed field gel electrophoresis (PFGE) analysis revealed a high genetic heterogeneity of S. aureus among both patients and controls. This indicates that presence of different strains of S. aureus can maintain a chronic inflammation in symptomatic nasal septal perforations. Objective The purpose of this study was to investigate the microbial flora around nasal septal perforations in patients having severe symptoms regarding bleeding, obstruction, and crustation associated with their perforation. Methods Twenty-five patients with untreated symptomatic nasal septal perforations were included. For culture, swabs around the perforations were collected. Bacteria were identified with standard laboratory techniques including a MALDI-TOF mass spectrometer. Epidemiological analysis was done using PFGE protocols. Bacteriological data were compared with data from a healthy control group. Results Staphylococcus aureus was present in the mucosa surrounding the nasal perforation significantly more often (p < 0.0001) in the patients (88%) compared to a control group (13%). Corynebacterium spp. and Propionibacterium spp. were significantly more frequently identified in the control group. The PFGE analysis of S. aureus strains revealed a high genetic heterogeneity and no specific S. aureus genotypes were associated with septal perforation.

BACKGROUND: Pyrazinamide (PZA) is a key drug in the treatment of tuberculosis (TB), including multidrug-resistant TB. Drug susceptibility testing (DST) of Mycobacterium tuberculosis against PZA is not included in the World Health Organization's yearly proficiency testing. There is an increasing need to establish quality control of PZA DST. OBJECTIVE: To evaluate the performance of PZA DST and to introduce a quality assurance system for the test in Sweden. METHOD: Panels with PZA-susceptible and -resistant isolates were used in three rounds of proficiency testing in all five Swedish clinical TB laboratories and our reference laboratory. All laboratories used the MGIT 960 system. Minimum inhibitory concentrations (MICs) were determined and the pncA gene was sequenced to further characterise the 52 panel strains. RESULTS: Good agreement was seen between the phenotypic PZA DST and pncA sequence data, and MIC determination confirmed high levels of resistance. However, in contrast to other drugs, for which correct proficiency test results were observed, specificity problems occurred for PZA DST in some laboratories. CONCLUSIONS: In Sweden, using panel testing, differences were seen in the proficiency of TB laboratories in correctly identifying PZA susceptibility. Improved results were noted in the third round; PZA has therefore been included in yearly proficiency testing.

The aim of this study was to determine antibiotic susceptibility of Propionibacterium acnes isolates from prostate. Prostate-derived P. acnes isolates (n = 24, Umeå & Örebro, Sweden, 2007-2010) and a panel of control strains (n = 25, Sweden) collected from skin and deep infections were assessed for resistance to penicillin G, piperacillin-tazobactam, imipenem, gentamicin, azithromycin, erythromycin, vancomycin, ciprofloxacin, moxifloxacin, tetracycline, tigecycline, fusidic acid, clindamycin, rifampicin, linezolid, daptomycin, trimethoprim-sulfamethoxazole, and metronidazole. In addition, the isolates were tested for inducible clindamycin resistance. All prostate derived P. acnes isolates displayed wild-type distribution of MIC-values, without evidence of acquired resistance. In the reference panel, 5 of 25 isolates had acquired macrolide resistance with cross-resistance to azithromycin, clindamycin, and erythromycin. In addition, one of these isolates was resistant to tetracycline.

To explore the colonizing bacterial flora of the nasal septum area, that is mostly afflicted by perforations, 101 healthy police students had swab samples taken from that location. The described culture strategy recovered positive cultures from 95% of the test subjects and from 60% with more than one organism. In total, 191 bacterial isolates were classified according to colony morphology, Gram-stain and a panel of standard laboratory techniques. A part of the bacteria was identified to species-level by biochemical methods and by sequencing of the 16S rRNA gene. The predominant finding was Gram-positive irregular rods - 65 presumptive Corynebacterium isolates, both lipophilic and non-lipophilic, and 37 anaerobic Propionibacterium isolates. The second largest bacterial group was Gram-positive catalase-positive cocci, of which 13 isolates were identified as Staphylococcus aureus and 53 as coagulase-negative staphylococci. The few potential airway pathogens included Streptococcus pneumonia (n = 1) and Moraxella catarrhalis (n = 3) isolates. The bacterial flora colonizing the nasal septum mainly consists of Gram-positive bacteria. Although of low virulence, the microbial flora may impact on occlusion treatment of nasal septum perforations with silicone obturators.

The number of human visitors to Antarctica is increasing rapidly, and with it a risk of introducing infectious organisms to native animals. To study the occurrence of salmonella serotypes in sub- Antarctic wildlife, faecal samples were collected from gentoo penguins, macaroni penguins, gray-headed albatrosses, black-browed albatrosses and Antarctic fur seals on Bird Island in the South Georgian archipelago during the austral summer of 1996 and 1998. In 1996, S. havana, S. typhimurium and S. enteritidis were isolated from 7% of gentoo penguins and 4% of fur seals. In 1998, however, 22% of fur seals were found to be infected with S. havana, S. enteritidis and S. newport. All isolates, except one, showed identical pulsed-field gel electrophoresis-patterns within each serotype, irrespective of sampling year and animal reservoir. No significant antibiotic resistance was found. The very low heterogeneity in the salmonella isolates found could either indicate a high genetic adaptation of the bacteria to the environment or a recent introduction of salmonella into the area.

Birds have been thought to play a role in transmitting infectious agents like influenza, Borrelia and Salmonella. To investigate the role of migrating birds in the dispersal of enteropathogenic bacteria, stool samples from 151 wild birds (50 gulls and 101 passerines) just entering Sweden from their winter grounds were analysed for Salmonella spp., Campylobacter spp. and EHEC O157:H7. The thermophilic isolated enteropathogens found were further analysed by antibiograms. Among the 50 gulls examined, we found 2 isolates of Salmonella typhimurium with multiple antibiotic resistance. Three isolates of C. jejuni were found in the 101 stool samples from passerines. We did not isolate EHEC O157:H7 in any of the bird stools examined.