Global event-based surveillance of chemical incidents.

BACKGROUND: The number of chemicals in our society and in our daily lives continues to increase. Accompanying this is an increasing risk of human exposure to and injury from hazardous substances. Performing regular, structured surveillance of chemical incidents allows a greater awareness of the types of chemical hazards causing injury and the frequency of their occurrence, as well as providing a better understanding of exposures. OBJECTIVE: The objective of performing event-based surveillance (EBS) and capturing chemical incidents is to use this information to increase the situational awareness of chemical incidents, improve the management of these incidents and to inform measures to protect public health. METHODS: This paper describes a method for EBS for chemical incidents, including the sources used, storing the gathered information and subsequent analysis of potential trends in the data. RESULTS: We describe trends in the type of incidents that have been detected, the chemicals involved in these incidents and the health effects caused, in different geographic regions of the world. SIGNIFICANCE: The methodology presented here provides a rapid and simple means of identifying chemical incidents that can be set up rapidly and with minimal cost, the outputs of which can be used to identify emerging risks and inform preparedness planning, response and training for chemical incidents.

Development of a mechanism for the rapid risk assessment of cross-border chemical health threats.

BACKGROUND: Chemical incidents can result in harm to public health and the environment. Although most are localised and have little impact, some affect wide areas, a range of sectors and may lead to many casualties. A public health response to assess the risks and provide advice to authorities and the public is usually required. In some cases, incidents may affect more than one country and require effective cross-border communication and coordination. OBJECTIVE: We describe tools and mechanisms to improve health security from cross-border chemical health threats and to support the implementation of the Decision of the European Parliament and the Council of the European Union (EU) on serious cross-border threats to health (Decision 1082/2013/EU). METHODS: Experts were recruited to a network and their suitability was assessed by using a skills framework. Input by relevant stakeholders such as the World Health Organisation and the European Centre for Disease Prevention and Control, followed by EU-wide exercises, ensured that tools developed were fit for purpose. RESULTS: A network of public health risk assessors and a methodology for providing rapid independent expert public health advice during a chemical emergency have been developed. SIGNIFICANCE: We discuss the legacy of these mechanisms including their incorporation into the working arrangements for the EU Scientific Committee for Health, Environment and Emerging Risks and future developments in the field.

Chemical warfare agent simulants for human volunteer trials of emergency decontamination: A systematic review.

Incidents involving the release of chemical agents can pose significant risks to public health. In such an event, emergency decontamination of affected casualties may need to be undertaken to reduce injury and possible loss of life. To ensure these methods are effective, human volunteer trials (HVTs) of decontamination protocols, using simulant contaminants, have been conducted. Simulants must be used to mimic the physicochemical properties of more harmful chemicals, while remaining non-toxic at the dose applied. This review focuses on studies that employed chemical warfare agent simulants in decontamination contexts, to identify those simulants most suitable for use in HVTs of emergency decontamination. Twenty-two simulants were identified, of which 17 were determined unsuitable for use in HVTs. The remaining simulants (n = 5) were further scrutinized for potential suitability according to toxicity, physicochemical properties and similarities to their equivalent toxic counterparts. Three suitable simulants, for use in HVTs were identified; methyl salicylate (simulant for sulphur mustard), diethyl malonate (simulant for soman) and malathion (simulant for VX or toxic industrial chemicals). All have been safely used in previous HVTs, and have a range of physicochemical properties that would allow useful inference to more toxic chemicals when employed in future studies of emergency decontamination systems.

Dissecting the taxonomic heterogeneity within Propionibacterium acnes: proposal for Propionibacterium acnes subsp. acnes subsp. nov. and Propionibacterium acnes subsp. elongatum subsp. nov.

Propionibacterium acnes subsp. acnes subsp. nov. and Propionibacterium acnes subsp. elongatum subsp. nov. are described. These emanate from the three known phylotypes of P. acnes, designated types I, II and III. Electron microscopy confirmed the filamentous cell shape of type III, showing a striking difference from types I/II, which were short rods. Biochemical tests indicated that, in types I/II, either the pyruvate, l-pyrrolidonyl arylamidase or d-ribose 2 test was positive, whereas all of these were negative among type III strains. Matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) spectra, which profile mainly their ribosomal proteins, were different between these two groups. Surface-enhanced laser-desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) spectra of all phylotypes revealed a specific protein biomarker that was overexpressed in type III strains compared with types I/II only when grown aerobically. Reference strains had high whole-genome similarity between types I (>91 %) and II (>75 %), but a considerably lower level of 72 % similarity with type III. recA and gyrB sequence dendrograms confirmed the distant relatedness of type III, indicating the presence of two distinct centres of variation within the species P. acnes. On the other hand, cellular fatty acid profiles and 16S rRNA gene sequence relatedness (>99.3 %) circumscribed the species. Thus, we propose two subspecies, Propionibacterium acnes subsp. acnes subsp. nov. for types I/II and Propionibacterium acnes subsp. elongatum subsp. nov. for type III. The type strain of Propionibacterium acnes subsp. acnes is NCTC 737T ( = ATCC 6919T = JCM 6425T = DSM 1897T = CCUG 1794T), while the type strain of Propionibacterium acnes subsp. elongatum is K124T ( = NCTC 13655T = JCM 18919T).

Complete Genome Sequence of the Hypervirulent Bacterium Clostridium difficile Strain G46, Ribotype 027.

Clostridium difficile is one of the leading causes of antibiotic-associated diarrhea in health care facilities worldwide. Here, we report the genome sequence of C. difficile strain G46, ribotype 027, isolated from an outbreak in Glamorgan, Wales, in 2006.

False extended-spectrum {beta}-lactamase phenotype in clinical isolates of Escherichia coli associated with increased expression of OXA-1 or TEM-1 penicillinases and loss of porins.

OBJECTIVES: Two clinical isolates of Escherichia coli, EC18 and EC21, were non-susceptible (MICs 4-16 mg/L) to cefpirome and cefepime, with marked synergy with clavulanate, yet were susceptible to cefotaxime and ceftazidime (MICs ≤ 1 mg/L). EC19, from the same patient as EC21, was susceptible to all four cephalosporins. We sought to characterize the molecular basis of resistance in isolates EC18 and EC21. METHODS: PFGE was used to study the genetic relationships of the isolates, and MICs were determined. ß-Lactamases were characterized by PCR, isoelectric focusing (IEF), construction of genomic libraries and sequencing. A double mutant of E. coli J53 was constructed, lacking OmpC and OmpF porins. Plasmids from clinical isolates were transformed into E. coli J53 and J53ΔompCF. Outer membrane proteins (OMPs) were analysed by SDS-PAGE and OmpA by matrix-assisted laser desorption ionization time-of-flight/time-of-flight mass spectrometry. Expression of omp and bla genes was analysed by RT-PCR. RESULTS: Isolates EC19 and EC21 had identical PFGE profiles, whereas EC18 was distinct. PCR and IEF confirmed ß-lactamases with pIs of 5.4 (TEM-1) in EC18 and 7.4 (OXA-1) in both EC19 and EC21. EC18 had bla(TEM-1b) with the strong promoter P5 and lacked OmpC and OmpF. RT-PCR showed stronger expression of bla(OXA-1) in EC21 versus EC19, along with diminished expression of OmpC, though with increased OmpF. Plasmids extracted from EC18 and EC21 conferred increased MICs of cefpirome and cefepime, although susceptibility to cefotaxime and ceftazidime was retained. CONCLUSIONS: The 'cefpiromase' or 'cefepimase' ESBL phenotype of the clinical isolates non-susceptible to cefpirome and cefepime resulted from high expression of TEM-1 or OXA-1 ß-lactamases combined with loss of porins.

Whole-genome comparison of two Acinetobacter baumannii isolates from a single patient, where resistance developed during tigecycline therapy.

OBJECTIVES: The whole genomes of two Acinetobacter baumannii isolates recovered from a single patient were sequenced to gain insight into the nature and extent of genomic plasticity in this important nosocomial pathogen over the course of a short infection. The first, AB210, was recovered before tigecycline therapy and was susceptible to this agent; the second, AB211, was recovered after therapy and was resistant. METHODS: DNA from AB210 was sequenced by 454 GS FLX pyrosequencing according to the standard protocol for whole-genome shotgun sequencing, producing ∼250 bp fragment reads. AB211 was shotgun sequenced using the Illumina Genetic Analyzer to produce fragment reads of exactly 36 bp. Single nucleotide polymorphisms (SNPs) and large deletions detected in AB211 in relation to AB210 were confirmed by PCR and DNA sequencing. RESULTS: Automated gene prediction detected 3850 putative coding sequences (CDSs). Sequence analysis demonstrated the presence of plasmids pAB0057 and pACICU2 in both isolates. Eighteen putative SNPs were detected between the pre- and post-therapy isolates, AB210 and AB211. Three contigs in AB210 were not covered by reads in AB211, representing three deletions of ∼15, 44 and 17 kb. CONCLUSIONS: This study demonstrates that significant differences were detectable between two bacterial isolates recovered 1 week apart from the same patient, and reveals the potential of whole-genome sequencing as a tool for elucidating the processes responsible for changes in antibiotic susceptibility profiles.