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Here we report on the development of a discriminatory real-time assay for the rapid identification of Burkholderia pseudomallei isolates and the evaluation of this assay for sensitivity against related species and detection in spiked human blood samples. The assay targets a 115-base-pair region within orf2 of the B. pseudomallei type III secretion system gene cluster and distinguishes B. pseudomallei from other microbial species. Assay performance was evaluated with 224 geographically, temporally, and clinically diverse B. pseudomallei isolates from the Centers for Disease Control and Prevention strain collection. This represents the first real-time PCR for rapid and sensitive identification of B. pseudomallei that has been tested for crossreactivity with 23 Burkholderia mallei, 5 Burkholderia thailandensis, and 35 Burkholderia and 76 non-Burkholderia organisms which have historically presented diagnostic challenges. The assay performed with 100% specificity.

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Members of the genus Brucella are categorized as biothreat agents and pose a hazard for both humans and animals. Current identification methods rely on biochemical tests that may require up to 7 days for results. We sequenced the 16S rRNA genes of 65 Brucella strains along with 17 related strains likely to present a differential diagnostic challenge. All Brucella 16S rRNA gene sequences were determined to be identical and were clearly different from the 17 related strains, suggesting that 16S rRNA gene sequencing is a reliable tool for rapid genus-level identification of Brucella spp. and their differentiation from closely related organisms.Brucella spp., the causative agents of brucellosis, are pathogenic to a variety of domesticated and wild animals. The genus Brucella is comprised of gram-negative, facultative, intracellular pathogens (1). Phenotypic characteristics, antigenic variation, and prevalence of infection in different animal hosts have resulted in the initial recognition of six species: B. abortus (cattle), B. melitensis (goats/sheep), B. suis (swine), B. canis (dogs), B. ovis (rams), and B. neotomae (desert rats) (13,27). Recently two Brucella strains from different marine mammals have been reported (7,11,22), and the names B. pinnipediae (seal/otter) and B. cetaceae (porpoise/whale) have been proposed (12). DNA hybridization analyses indicate a high level of homology among the brucellae, suggesting that the genus Brucella may comprise only one species with several biovars (40).Brucellosis impacts public health and agricultural economies worldwide because of its high infectivity rate (13). Brucella spp. have also long been considered a potential biological weapon (20), and currently, with the renewed threat of biological warfare and agricultural terrorism, B. melitensis, B. suis, and B. abortus are listed as category B biothreat agents by the Centers for Disease Control and Prevention Strategic Planning Group (34).Infections in humans generally result from (i) transmission via the gastrointestinal route by the consumption of unpasteurized diary products (18, 32) and contaminated meat (25), (ii) airborne transmission in animal husbandry by inhaling dust contaminated by aborted tissues (23), and (iii) transmission caused by laboratory-associated exposure to aerosols (26). In the event of a bioterror attack, the preferred method of dissemination would most likely be via aerosol (3,20,34).Because of the limited availability of animal vaccines, cost of animal inoculations, a lack of vaccines for human use (13, 37), and its low infectious dose for humans, human brucellosis is endemic in many parts of the world, including the Mediterranean region, Latin America, Asia, and Africa. The reported incidence varies from Ͻ0.01 to Ͼ200 per 100,000 population (13). Human brucellosis is rare in the United States, with approximately 100 human cases reported per year, mostly caused by consumption of unpasteurized diary products and, to a lesser degree, occupational exposure (10, 38).The rapidity with which a laborato...

Fifteen years after primary vaccination starting at birth, 8% of participants had evidence of past HB virus infection, but none had chronic infection. Absence of an anamnestic response to an additional vaccine dose, seen in half of participants, might indicate waning immunity.

We report on three cases of meningococcal disease caused by ciprofloxacin-resistant Neisseria meningitidis, one in North Dakota and two in Minnesota. The cases were caused by the same serogroup B strain. To assess local carriage of resistant N. meningitidis, we conducted a pharyngeal-carriage survey and isolated the resistant strain from one asymptomatic carrier. Sequencing of the gene encoding subunit A of DNA gyrase (gyrA) revealed a mutation associated with fluoroquinolone resistance and suggests that the resistance was acquired by means of horizontal gene transfer with the commensal N. lactamica. In susceptibility testing of invasive N. meningitidis isolates from the Active Bacterial Core surveillance system between January 2007 and January 2008, an additional ciprofloxacin-resistant isolate was found, in this case from California. Ciprofloxacin-resistant N. meningitidis has emerged in North America.

Summary Background To combat Neisseria meningitidis serogroup A epidemics in the meningitis belt of sub-Saharan Africa, a meningococcal serogroup A conjugate vaccine (MACV) has been progressively rolled out since 2010. We report the first meningitis epidemic in Niger since the nationwide introduction of MACV. Methods We compiled and analysed nationwide case-based meningitis surveillance data in Niger. Cases were confirmed by culture or direct real-time PCR, or both, of cerebrospinal fluid specimens, and whole-genome sequencing was used to characterise isolates. Information on vaccination campaigns was collected by the Niger Ministry of Health and WHO. Findings From Jan 1 to June 30, 2015, 9367 suspected meningitis cases and 549 deaths were reported in Niger. Among 4301 cerebrospinal fluid specimens tested, 1603 (37·3%) were positive for a bacterial pathogen, including 1147 (71·5%) that were positive for N meningitidis serogroup C (NmC). Whole-genome sequencing of 77 NmC isolates revealed the strain to be ST-10217. Although vaccination campaigns were limited in scope because of a global vaccine shortage, 1·4 million people were vaccinated from March to June, 2015. Interpretation This epidemic represents the largest global NmC outbreak so far and shows the continued threat of N meningitidis in sub-Saharan Africa. The risk of further regional expansion of this novel clone highlights the need for continued strengthening of case-based surveillance. The availability of an affordable, multivalent conjugate vaccine may be important in future epidemic response.