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Francisella tularensis has been associated with naturally occurring waterborne outbreaks and is also of interest as a potential biological weapon. Recovery of this pathogen from water using cultural methods is challenging due to the organism's fastidious growth requirements and interference by indigenous bacteria. A 15-min acid treatment procedure prior to culture on a selective agar was evaluated for recovery of F. tularensis from seeded water samples. Mean levels of reduction of virulent strains of F. tularensis subsp. holarctica and subsp. tularensis were less than 20% following acid treatment. The attenuated live vaccine strain (LVS) was less resistant to acid exposure. The acid treatment procedure coupled with plating on cystine heart agar with rabbit blood and antibiotics (CHARBab) allowed the isolation of F. tularensis seeded into five natural water samples. [ABSTRACT FROM AUTHOR]

Haematospirillum jordaniae is a gram-negative bacterium that has been identified in the blood of septic patients. The environmental source or potential zoonotic host of this bacterium, recently described as a human bacterial pathogen is unknown. An increasing number of H. jordaniae clinical infections identified by our laboratory suggested the need for an assay to detect this organism in order to aid clinical teams and practitioners with faster identification and treatment thus improving patient prognosis. Described here is a real-time qualitative PCR assay designed using gene targets identified from the analysis of 14 H. jordaniae genomes sequenced by the Center for Disease Control and Prevention's (CDC) Special Bacterial Reference Laboratory (SBRL) culture collection. The assay was validated on clinical EDTA whole blood samples as well as on plasma and determined to be effective at detecting as few as 10 copies per microliter (10,000 copies per mL, 4 log/mL) for whole blood samples and 1 copy per microliter (1,000 copies per mL, 3 log mL) for plasma samples., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Inc.)

Introduction: Following a declaration by the World Health Organization that Liberia had successfully interrupted Ebola virus transmission on May 9th, 2015; the country entered a period of enhanced surveillance. The number of cases had significantly reduced prior to the declaration, leading to closure of eight out of eleven Ebola testing laboratories. Enhanced surveillance led to an abrupt increase in demand for laboratory services. We report interventions, achievements, lessons learned and recommendations drawn from enhancing laboratory capacity., Methods: Using archived data, we reported before and after interventions that aimed at increasing laboratory capacity. Laboratory capacity was defined by number of laboratories with Ebola Virus Disease (EVD) testing capacity, number of competent staff, number of specimens tested, specimen backlog, daily and surge testing capacity, and turnaround time. Using Stata 14 (Stata Corporation, College Station, TX, USA), medians and trends were reported for all continuous variables., Results: Between May and December 2015, interventions including recruitment and training of eight staff, establishment of one EVD laboratory facility, implementation of ten Ebola GeneXpert diagnostic platforms, and establishment of working shifts yielded an 8-fold increase in number of specimens tested, a reduction in specimens backlog to zero, and restoration of turn-around time to 24 hours. This enabled a more efficient surveillance system that facilitated timely detection and containment of two EVD clusters observed thereafter., Conclusion: Effective enhancement of laboratory services during high demand periods requires a combination of context-specific interventions. Building and ensuring sustainability of local capacity is an integral part of effective surveillance and disease outbreak response efforts., Competing Interests: The authors declare no competing interest.

We provide complete circularized genome sequences of two mosquito-derived Elizabethkingia anophelis strains with draft sequences currently in the public domain (R26 and Ag1), and two novel E. anophelis strains derived from a different mosquito species, Anopheles sinensis (AR4-6 and AR6-8). The genetic similarity of all four mosquito-derived strains is remarkable.

Three human clinical isolates (X1654, X1655, and W9944) were recovered from the sputum and bronchial washings of two patients with pulmonary infections. The 16S rRNA gene sequence analysis of the isolates showed that they share 100 % sequence similarity with each other and belong to the genus Nocardia. Close phylogenetic neighbours are Nocardia brevicatena ATCC 15333(T) (98.6 %) and Nocardia paucivorans ATCC BAA-278T (98.4 %). The in silico DNA-DNA relatedness between the isolates ranges from 96.8 to 100 % suggesting that they belong to the same genomic species. The DNA-DNA relatedness between X1654 and N. brevicatena ATCC 15333(T) is 13.3 ± 2.3 % and N. paucivorans ATCC BAA-278T is 18.95 ± 1.1 % suggesting that they do not belong to the same genomic species. Believed to represent a novel species, these isolates were further characterised to establish their taxonomic standing within the genus. Chemotaxonomic data for isolate X1654 are consistent with those described for the genus Nocardia: this isolate produced saturated and unsaturated fatty acids, tuberculostearic acid (15.9 %), the major menaquinone was MK-8 (H4cyclic), mycolic acid chain lengths ranged from 38 to 58 carbons, produced meso-diaminopimelic acid with arabinose, glucose, and galactose as the whole cell sugars. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, and phosphatidylinositol mannosides. The DNA G+C content is 66.7 mol  %. Based on the combination of phenotypic, chemotaxonomic, and genotypic data for X1654, X1655, and W9944, we conclude that these isolates represent a novel species within the genus Nocardia for which we propose the name Nocardia donostiensis sp. nov. with X1654(T) (=DSM 46814(T) = CECT 8839(T)) as the type strain.

The CDC Special Bacteriology Reference Laboratory (SBRL) collection of human clinical pathogens contains several strains from the genus Devosia, usually found environmentally. We provide here the complete genome of strain H5989, which was isolated from a human cerebrospinal fluid (CSF) specimen and represents a putative novel species in the genus Devosia., (Copyright © 2015 Nicholson et al.)

The method detection limit (MDL, 99% chance of detecting a positive result in a single replicate), as per the United States Code of Federal Regulations, was determined for a protocol using an ultrafiltration based automated waterborne pathogen concentration device. Bacillus anthracis Sterne strain spores were seeded at low levels into 100 L reagent water samples. Suspect colonies were confirmed through morphological, chemical, and genetic tests. Samples of 100 L (n=14) of reagent water were seeded with five B. anthracis CFUs each. To confirm the estimated detection limit, a second set (n=19) of 100 L reagent water samples were seeded at a higher level (7 CFUs). The second estimate of the MDL could not be pooled with the first, due to significant difference in variance. A third trial (n=7) seeded with 10 CFUs produced an estimate of the MDL that could be pooled with the higher previous estimate. Another trial consisting of eight 100 L samples of tap water were seeded with approximately 7 CFUs. Recovery in these samples was not significantly different from the pooled MDL. Theoretically a concentration of 4.6 spores/100 L would be required for detection 95% of the time, based on a Poisson distribution. The calculated pooled MDL, based on experimental data was approximately 6 B. anthracis CFU/100 L (95% confidence interval 4.8 to 8.4). Detection at this level was achieved in municipal water samples.