Skin thickness measurements for optimal intradermal injections in children.

BACKGROUND: In the context of precision medicine and in response to the highly needed capacity of rapid interventions towards new infectious diseases and pandemic outbreaks, intradermal immunization is gaining increased attention. However, the currently used Mantoux technique for ID injection is difficult to standardize and requires training, especially when used in children. To allow determining the maximum penetration depth and needle characteristics for the development of a platform of medical devices suited for intradermal injection, VAX-ID® and to ensure an accurate ID injection in children, the epidermal and dermal thickness at the proximal ventral and dorsal forearm (PVF & PDF) and at the deltoid region in children aged 8 weeks to 18 years were assessed. The lateral part of the upper leg was assessed as well in children aged 8 weeks to 2 years since it is a commonly used injection site in this population. MATERIALS & METHODS: Mean thickness of the PVF, PDF, lateral part of the upper leg and deltoid were measured using high-frequency ultrasound. Association with gender, age and BMI was assessed using Mann-Whitney U Test, Spearman correlation and Wilcoxon Signed Ranks Test, respectively. RESULTS: Results showed an overall mean skin thickness of 0.99 mm (SD: 0.14 mm) at the PVF, 1.20 mm (SD: 0.17) at the PDF, 1.28 mm (SD: 0.16) at the lateral part of the upper leg and increasing to 1.32 mm (0.25) at the deltoid region. Age and BMI correlated significantly (p < 0.001) with skin thickness at all investigated body sites. Gender did not affect skin thickness in the investigated population. CONCLUSION: Significant differences in skin thickness at the PVF, PDF and deltoid region were seen according to age and BMI. An optimal needle length of 0.7 mm is advised to guarantee intradermal injection in children at all investigated injection sites. (NCT02727114).

Immunogenicity and safety of intradermal delivery of hepatitis B booster vaccine using the novel drug delivery device VAX-ID™.

BACKGROUND: Although intramuscular (IM) injection is still the most preferred method for vaccination, intradermal (ID) delivery may have several advantages over intramuscular and subcutaneous (SC), including an improved immune response and antigen dose sparing effect. However it is currently limited due to the difficulty in standardizing the injection technique often based on the Mantoux technique. Difficulties encountered using the Mantoux technique could be overcome by the use of alternative ID delivery systems that confer more uniform and standardized procedures. The aim of this study was to evaluate the performance of a newly developed intradermal injection device, VAX-ID™, via a proof-of-concept to assess the immunogenicity of a commercially available hepatitis B booster vaccination in healthy hepatitis B pre-immunised subjects. Additionally, device safety and tolerability was evaluated. MATERIALS AND METHODS: Three different routes of administration were compared over 4 groups, each receiving hepatitis B vaccine antigen: (1) standard IM injection in the deltoid region (HBVAXPRO® 10 µg/1 ml), (2) ID injection in the proximal posterior area of the forearm according to the Mantoux technique, (3) with VAX-ID™ in one forearm, or (4) with VAX-ID™ in both forearms. For ID injections 0.11 cc, of which 0.01 cc is overfill, was drawn from a vial containing HBVAXPRO® 40 µg/1 ml. Immunogenicity and safety were followed-up at day 0, 14, 30 and 210. RESULTS: A total of 48 subjects were included. All subjects showed an anamnestic response at 14 days post booster vaccination. Elevated titres persisted until end of follow-up at day 210. For the ID groups a 3 fold higher immune response at day 14 and day 30 was recorded compared to IM group. Local adverse events were more reported for ID compared to IM. CONCLUSIONS: The investigated ID injection device VAX-ID™ proves to be a good alternative to offer ID vaccination.

High frequency ultrasound to assess skin thickness in healthy adults.

BACKGROUND: Intradermal immunization is gaining increased attention due to multiple factors: (1) intradermal (ID) vaccination has been shown to induce improved immunogenicity compared to intramuscular (IM) vaccination; (2) ID vaccination has been shown to have a dose-sparing potential over IM leading to a reduced vaccine cost and an increased availability of vaccines worldwide. However, the currently used Mantoux technique for ID injection is difficult to standardize and requires training. The aim of the study was (1) to assess the epidermal and dermal thickness at the proximal ventral and dorsal forearm (PVF & PDF) and deltoid in adults aged 18-65years (2) to determine the maximum penetration depth and needle characteristics for the development of a platform of medical devices suited for intradermal injection, VAX-ID™. MATERIALS AND METHODS: Mean thickness of the PVF, PDF and deltoid were measured using high-frequency ultrasound of healthy adults aged 18-65years. Correlation with gender, age and BMI was assessed using Mann-Whitney U Test, Spearman correlation and Wilcoxon Signed Ranks Test, respectively. RESULTS: Results showed an overall mean skin thickness of 1.19mm (0.65-1.55mm) at the PVF, 1.44mm (0.78-1.84mm) at the PDF, and 2.12mm (1,16-3.19mm) at the deltoid. Thickness of PVF & PDF and deltoid were significantly different for men vs women (pmean<0.001, <0.001, <0.001, and pmin<0.001, 0.012, <0.001, respectively). A significant association was found for age at the deltoid region (p<0.001). Skin thickness for PVF, PDF & deltoid was significantly associated to BMI (p<0.001). CONCLUSION: Significant differences in skin thickness were seen for the PVF, PDF and deltoid region for gender, and BMI. Age only influenced the skin thickness at deltoid region. A needle length of 1.0mm is best option for intradermal injection at the dorsal forearm (NCT02363465).

The European Centre for Disease Prevention and Control (ECDC) pilot point prevalence survey of healthcare-associated infections and antimicrobial use.

A standardised methodology for a combined point prevalence survey (PPS) on healthcare-associated infections (HAIs) and antimicrobial use in European acute care hospitals developed by the European Centre for Disease Prevention and Control was piloted across Europe. Variables were collected at national, hospital and patient level in 66 hospitals from 23 countries. A patient-based and a unit-based protocol were available. Feasibility was assessed via national and hospital questionnaires. Of 19,888 surveyed patients, 7.1% had an HAI and 34.6% were receiving at least one antimicrobial agent. Prevalence results were highest in intensive care units, with 28.1% patients with HAI, and 61.4% patients with antimicrobial use. Pneumonia and other lower respiratory tract infections (2.0% of patients; 95% confidence interval (CI): 1.8­2.2%) represented the most common type (25.7%) of HAI. Surgical prophylaxis was the indication for 17.3% of used antimicrobials and exceeded one day in 60.7% of cases. Risk factors in the patient-based protocol were provided for 98% or more of the included patients and all were independently associated with both presence of HAI and receiving an antimicrobial agent. The patient-based protocol required more work than the unit-based protocol, but allowed collecting detailed data and analysis of risk factors for HAI and antimicrobial use.

Antifungal therapy in European hospitals: data from the ESAC point-prevalence surveys 2008 and 2009.

The study aimed to identify targets for quality improvement in antifungal use in European hospitals and determine the variability of such prescribing. Hospitals that participated in the European Surveillance of Antimicrobial Consumption Point Prevalence Surveys (ESAC-PPS) were included. The WHO Anatomical Therapeutic Chemical (ATC) classification for 'antimycotics for systemic use' (J02) 2009 version was used. Demographic data and information about indications and diagnoses were collected in 2008 and 2009. From 99,053 patients, 29,324 (29.6%) received antimicrobials. Antifungals represented 1529 of 40,878 (3.7%) antimicrobials. Antifungals were mainly (54.2%) administered orally. Hospital-acquired infections represented 44.5% of indications for antifungals followed by medical prophylaxis at 31.2%. The site of infection was not defined in 36.0% of cases but the most commonly targeted sites were respiratory (19.2%) and gastrointestinal (18.8%). The most used antifungal was fluconazole (60.5%) followed by caspofungin (10.5%). Antifungal-antibacterial combinations were frequently used (77.5%). The predominance of fluconazole use in participating hospitals could result in an increase in prevalence of inherently resistant fungi, increasing the need for newer antifungals. Although acknowledging that antifungal prophylaxis in the immunocompromised host needs further exploration, repetitive surveys using ESAC-PPS methodology may help to monitor the effects of interventions set to regulate antifungal use.

Virulence determinants in vancomycin-resistant Enterococcus faecium vanB: clonal distribution, prevalence and significance of esp and hyl in Australian patients with haematological disorders.

European studies have suggested that the esp gene and other virulence factors have roles in vancomycin-resistant Enterococcus faecium (VREfm) infections. The aim of this study was to examine the relationship between the spectrum of clinical disease and putative virulence factors in vanB VREfm isolates. A multiplex polymerase chain reaction was used to amplify potential virulence genes (asa1, gel E, cylA, esp and hyl) in VREfm isolates obtained from an Australian population of haematology patients. Clonality was assessed by pulsed-field gel electrophoresis (PFGE) and automated ribotyping. Infection, requirement for intensive care unit (ICU) admission and all-cause 30-day mortality were used as clinical indicators of organism virulence. Forty-one VREfm vanB isolates (41 patients; 14 infected and 27 colonised only) were analysed. Thirty-five of these isolates were typed by PFGE, 31 of which were represented by three clusters. The esp gene was identified in 22 of 27 (81.5%) screening and 11 of 14 (78.6%) infection-associated isolates. One isolate was hyl gene positive, and no isolate contained asa1, gel E or cylA genes. VREfm infection was independently associated with host factors (underlying diagnosis of acute myeloid leukaemia, age

Outbreak of hospital-adapted clonal complex-17 vancomycin-resistant Enterococcus faecium strain in a haematology unit: role of rapid typing for early control.

OBJECTIVES: To describe the investigation and molecular characterization of a vancomycin-resistant Enterococcus faecium (VREF) strain responsible for a nosocomial outbreak in the haematology unit of a tertiary-care university hospital. PATIENTS AND METHODS: Two patients admitted to the haematology unit developed infection/colonization with VREF over a 3 month period when compared with none in the 2 previous years. On the basis of the identification of a clonal link between these two strains, weekly rectal screening was implemented for all patients in the haematology unit and contact precautions were extended to VREF carriers. In the following 6 month period, 11 patients colonized with VREF were detected. No further case was detected in the following 1 year period. RESULTS: VREF isolates from the haematology unit carried the vanA gene and were multiresistant to antimicrobial agents, including high-level resistance to vancomycin, teicoplanin and ampicillin. This resistance profile restricted the choice of antimicrobial therapy to linezolid or investigational drugs such as tigecycline. Molecular analysis showed that 11 of 13 (85%) VREF isolates belonged to pandemic clonal complex-17 carrying the esp and hyl virulence genes. CONCLUSIONS: Rapid typing and infection control measures, including early reinforcement of barrier precautions combined with weekly rectal surveillance cultures, were followed by control of nosocomial spread of this VREF clone.

Intraspecific genotypic characterization of Lactobacillus rhamnosus strains intended for probiotic use and isolates of human origin.

A set of 118 strains of the species Lactobacillus rhamnosus was collected, including probiotic strains, research strains with potential probiotic properties, food starter cultures, and human isolates. The majority of the strains were collected from companies, hospitals, or culture collections or were obtained after contacting authors who reported clinical case studies in the literature. The present work aimed to reveal the genotypic relationships between strains of these diverse sources. All strains were initially investigated using fluorescent amplified fragment length polymorphism (FAFLP) with three different primer combinations. Numerical analysis of FAFLP data allowed (i) confirmation of the identification of all strains as members of L. rhamnosus and (ii) delineation of seven stable intraspecific FAFLP clusters. Most of these clusters contained both (potentially) probiotic strains and isolates of human origin. For each of the clusters, strains of different sources were selected for pulsed-field gel electrophoresis (PFGE) of macrorestriction fragments obtained with the enzymes NotI and AscI. Analysis of PFGE data indicated that (i) some (potentially) probiotic strains were indistinguishable from other probiotic strains, suggesting that several companies may use duplicate cultures of the same probiotic strain, and (ii) in a number of cases human isolates from sterile body sites were indistinguishable from a particular probiotic strain, suggesting that some of these isolates may be reisolations of commercial strains.