Aitziber Aguinaga

Changing epidemiology of invasive pneumococcal disease following increased coverage with the heptavalent conjugate vaccine in Navarre, Spain

The present study evaluated changes in the incidence of invasive pneumococcal disease (IPD) and the pattern of serotypes isolated in Navarre, Spain, after the introduction and increased coverage of the heptavalent pneumococcal conjugate vaccine (PCV7). All cases with isolation of pneumococcus from normally sterile bodily fluids were included. The incidence of IPD in children and adults was compared for the periods 2001-2002 and 2006-2007. By the end of 2002, only 11% of children aged <5 years had received any dose of PCV7, whereas, beginning in 2007, the proportion exceeded 50%. Among the cases of IPD aged <5 years, the percentage of those vaccinated increased from 7% during 2001-2002 to 53% during 2006-2007 (p <0.001). The incidence of IPD from PCV7-serotypes decreased by 85% in children <5 years (p <0.001), by 45% in the population aged 5-64 years (p 0.10) and by 68% in those >or=65 years (p 0.004). By contrast, the incidence of IPD from non-PCV7 serotypes increased by 40% overall (p 0.006). The incidence of IPD from all serotypes did not change significantly in children <5 years (from 83 to 72 per 100 000) or in the total population (from 15.8 to 16.3 per 100 000). The percentage of cases as a result of serotypes 7 and 19A increased significantly in both children and adults. No significant changes were seen in the clinical forms of IPD. The pattern of serotypes causing IPD has changed, in both children and adults, following the increased coverage of PCV7, although the incidence has been reduced only slightly.

Reduced incidence of invasive pneumococcal disease after introduction of the 13-valent conjugate vaccine in Navarre, Spain, 2001–2013

Pneumococcal conjugate vaccines (PCVs) were licensed for use in children and became available for private purchase in Spain in 2001 (PCV7), 2009 (PCV10) and 2010 (PCV13). This study evaluates changes in the incidence of invasive pneumococcal disease (IPD) and the pattern of serotypes isolated in Navarre, Spain, between the period of use of PCV7 (2004-2009) and that of PCV13 (2010-2013). The percentage of children <2 years who received at least one dose of PCV in these periods ranged from 25 to 61% and 61 to 78%, respectively. Between the periods 2004-2009 and 2010-2013 IPD incidence declined by 37%, from 14.9 to 9.4 cases/100,000 inhabitants (p<0.001). In children <5 years it fell by 69% (p<0.001), in persons aged 5-64 years, by 34% (p<0.001), and in those ≥ 65, by 23% (p=0.024). The incidence of cases due to PCV13 serotypes declined by 81% (p<0.001) in children <5 years and by 52% (p<0.001) in the whole population. No significant changes were seen in the distribution of clinical presentations or in disease severity. The incidence of IPD has declined and the pattern of serotypes causing IPD has changed notably in children and moderately in adults following the replacement of PCV7 by PCV13.

Real time monitoring of the impedance characteristics of Staphylococcal bacterial biofilm cultures with a modified CDC reactor system.

Detection of device-associated infectious processes is still an important clinical challenge. Bacteria grow adhered to the device surfaces creating biofilms that are resistant to antimicrobial agents, increasing mortality and morbidity. Thus there is need of a surgical procedure to remove the indwelling infected device. The elevated cost of these procedures, besides patients discomfort and increased risks, highlights the need to develop more efficient, accurate and rapid detection methods. Biosensors integrated with implantable devices will provide an effective diagnostic tool. In vivo, rapid and sensitive detection of bacteria attached to the device surfaces will allow efficient treatments. Impedance spectroscopy technique would be an adequate tool to detect the adherence and the growth of the microorganism by monitoring the impedance characteristics. In this work a label-free interdigitated microelectrode (IDAM) biosensor has been developed to be integrated with implantable devices. Impedance characterization of Staphylococcus epidermidis biofilms has been performed achieving electrical monitoring of the bacterial growths in a few hours from the onset of the infection. This pathogen represents the most common microorganism related to intravascular catheters associated infections. The experimental setup presented in this work, a modified CDC biofilm reactor, simulates the natural environment conditions for bacterial biofilm development. The results prove that the low range of frequency is the most suitable setting for monitoring biofilm development. Our findings prove the effectiveness of this technique which shows variations of 59% in the equivalent serial capacitance component of the impedance.

Daptomycin lock therapy for grampositive long-term catheter-related bloodstream infections

Introduction:  To evaluate the efficacy of Daptomycin (DPT) lock therapy in the treatment of Grampositive long‐term catheter‐related bloodstream infections (LT‐CRBI).

Effectiveness of the antibiotic lock therapy for the treatment of port-related enterococci, Gram-negative, or Gram-positive bacilli bloodstream infections

OBJECTIVE The purpose of this study is to evaluate the efficacy of antibiotic lock therapy to treat port-related enterococci, Gram-negative, or Gram-positive bacilli bloodstream infections. PATIENTS AND METHODS We conducted a prospective observational study including all patients with port-related bacteremia diagnosed at the Clinica Universitaria de Navarra, Pamplona, Spain. During a 36-month period, 110 patients were diagnosed with port-related bacteremia. Of these patients, 18 met criteria to be enrolled in the study. They were treated with a combination of systemic and antibiotic lock therapy (12-24 h/day during 7-14 days). Treatment effectiveness was assessed by clinical and microbiologic criteria. RESULTS Treatment was associated with clinical and microbiologic success in 88.8% of our patients (2/2 of the Propionibacterium acnes, 5/5 of the Corynebacterium spp., 6/7 of the Gram-negative bacillus, and 3/4 of the Enterococcus faecium port-related bloodstream infections). Mean increase of port life span for all patients after bacteremia was 288 days (range, 0-1403 days). CONCLUSION Antibiotic lock therapy combined with systemic antibiotics appears to be a safe and effective treatment of port-related bacteremia caused by enterococci, Gram-negative, or Gram-positive bacilli if the patient is stable and no septic syndrome is associated.

Lysostaphin and clarithromycin: a promising combination for the eradication of Staphylococcus aureus biofilms

1] Hawser SP. Activity of tigecycline against meticillin-resistant Staphylococcus aureus (MRSA) from respiratory tract sources. Int J Antimicrob Agents 2010;35:414–15. 2] Jones RN, Ross JE, Bell JM, Utsuki U, Fumiaki I, Kobayashi I, et al. Zyvox Annual Appraisal of Potency and Spectrum program: linezolid surveillance program results for 2008. Diagn Microbiol Infect Dis 2009;65:404–13. 3] Clinical and Laboratory Standards Institute. Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically; approved standard. 8th ed. Document M07-A8. Wayne, PA: CLSI; 2009. 4] Kunkel M, Chastre JE, Kollef M, Niederman M, Shorr AF, Wunderink RG, et al. Linezolid vs vancomycin in the treatment of nosocomial pneumonia proven due to methicillin-resistant Staphylococcus aureus. In: 48th IDSA, October 21–24, 2010. 2010. Abstr. LB-49. 5] Bounthavong M, Hsu DI. Efficacy and safety of linezolid in methicillin-resistant Staphylococcus aureus (MRSA) complicated skin and soft tissue infection (cSSTI): a meta-analysis. Curr Med Res Opin 2010;26:407–21.

Effectiveness of teicoplanin versus vancomycin lock therapy in the treatment of port-related coagulase-negative staphylococci bacteraemia: a prospective case-series analysis

The aim of this study was to analyse the effectiveness of teicoplanin versus vancomycin lock therapy in the treatment of coagulase-negative staphylococci (CoNS) venous access port-related bloodstream infection (BSI). The study included 44 consecutive patients during a 36-month prospective case-series study. The primary endpoint was failure to cure. Treatment was successful in 39 patients. At the end of the study, the cumulative port survival rate was 100% in the teicoplanin lock group compared with 77% in the vancomycin lock group (P=0.06). In the Cox regression analysis, fever beyond 48 h of treatment was a significant predictor of treatment failure (P=0.02). Use of vancomycin or teicoplanin locks had an effectiveness of 88.6% in the treatment of CoNS port-related BSI. Teicoplanin locks reduced the failure rate from 18.5% to 0% compared with vancomycin locks. The presence of fever after beginning antimicrobial lock therapy was associated with treatment failure.

Effect of Repeated Vaccination With the Same Vaccine Component Against 2009 Pandemic Influenza A(H1N1) Virus

Background The 2009 pandemic influenza A(H1N1) (A[H1N1]pdm09) vaccine component has remained unchanged from 2009. We estimate the effectiveness of current and prior inactivated influenza A(H1N1)pdm09 vaccination from influenza seasons 2010-2011 to 2015-2016. Methods Patients attended with influenza-like illness were tested for influenza. Four periods with continued A(H1N1)pdm09 circulation were included in a test-negative design. Results We enrolled 1278 cases and 2343 controls. As compared to individuals never vaccinated against influenza A(H1N1)pdm09, the highest effectiveness (66%; 95% confidence interval, 49%-78%) was observed in those vaccinated in the current season who had received 1-2 prior doses. The effectiveness was not statistically lower in individuals vaccinated in the current season only (52%) or in those without current vaccination and >2 prior doses (47%). However, the protection was lower in individuals vaccinated in the current season after >2 prior doses (38%; P = .009) or those currently unvaccinated with 1-2 prior doses (10%; P < .001). Current-season vaccination improved the effect in individuals with 1-2 prior doses and did not modify significantly the risk of influenza in individuals with >2 prior doses. Conclusion Current vaccination or several prior doses were needed for high protection. Despite the decreasing effect of repeated vaccination, current-season vaccination was not inferior to no current-season vaccination.

Combined effectiveness of prior and current season influenza vaccination in northern Spain: 2016/17 mid-season analysis

The 2016/17 mid-season vaccine effectiveness estimate against influenza A(H3N2) was 15% (95% confidence interval: −11 to 35) in Navarre. Comparing to individuals unvaccinated in the current and four prior seasons, effectiveness was 24% for current and 3–4 prior doses, 61% for current and 1–2 prior doses, 42% for only current vaccination, and 58% for 3–4 prior doses. This suggests moderate effectiveness for different combinations of vaccination in the current and prior seasons.

Interim effectiveness of trivalent influenza vaccine in a season dominated by lineage mismatched influenza B, northern Spain, 2017/18

The 2017/18 interim estimate of trivalent influenza vaccine effectiveness (VE) was 39% (95% confidence interval: 20–54) in Navarre. Compared with individuals unvaccinated in the current and five previous seasons, VE against influenza B was 41% for current and any prior doses, 67% for current vaccination only, and 22% for any prior doses, and 43%, 51% and 54%, respectively against influenza A(H3N2). This suggests moderate VE despite predominance of lineage mismatched influenza B.