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Madagascar reports more human plague (causative agent: Yersinia pestis) cases annually than any other country (1), often several hundred each season (typically September-March) (2). Y. pestis persists in multiple rural [...]

Sequence analyses and subtyping of Bacillus anthracis strains from Georgia reveal a single distinct lineage (Aust94) that is ecologically established. Phylogeographic analysis and comparisons to a global collection reveals a clade that is mostly restricted to Georgia. Within this clade, many groups are found around the country, however at least one subclade is only found in the eastern part. This pattern suggests that dispersal into and out of Georgia has been rare and despite historical dispersion within the country, for at least for one lineage, current spread is limited.

Francisella tularensis, a Tier 1 select agent (7), has 3 subspecies: tularensis (type A), holarctica (type B), and mediasiatica (Appendix 1 Figure, https://wwwnc. cdc.gov/EID/article/25/5/18-0363-App1.pdf). In humans, disease is caused by [...]

Plague, caused by the bacterium Yersinia pestis, is a fleaborne disease responsible for the death of tens of millions of persons throughout history (1,2). The bacterium spread to Madagascar in [...]

Tularemia is a disease caused primarily by 2 subspecies of Francisella tularensis: F. tularensis subsp. tularensis, which is restricted to North America; and F. tularensis subsp. holarctica, which is found [...]

Leptospirosis, caused by spirochetes of the genus Leptospira, is a neglected and potentially fatal disease that burdens impoverished communities of developing nations in tropical regions (1-4). The bacteria cause 1.7 [...]

Tularemia, caused by the bacterium Francisella tularensis, is a potentially severe disease that often causes unspecific symptoms; because of its low infectious dose and ease of dissemination, F. tularensis is [...]

Fraancisella tularensis is the etiologic agent of tularemia and a highly virulent category A biothreat agent (1,2). The most widely distributed subspecies is F. tularensis subsp. holarctica, which is found [...]

To the Editor: Tularemia is a zoonosis caused by the bacterium Francisella tularensis; the main forms of disease that occur in humans are ulceroglandular/glandular, oculoglandular, oropharyngeal, and respiratory. In Turkey, [...]

Background Pneumonic plague (PP), caused by Yersinia pestis , is the most feared clinical form of plague due to its rapid lethality and potential to cause outbreaks. PP outbreaks are now rare due to antimicrobial therapy. Methods A PP outbreak in Madagascar involving transmission of a Y. pestis strain resistant to streptomycin, the current recommended first-line treatment in Madagascar, was retrospectively characterized using epidemiology, clinical diagnostics, molecular characterization, and animal studies. Results The outbreak occurred in February 2013 in the Faratsiho district of Madagascar and involved 22 cases, including 3 untreated fatalities. The 19 other cases participated in funeral practices for the fatal cases and fully recovered after combination antimicrobial therapy: intramuscular streptomycin followed by oral co-trimoxazole. The Y. pestis strain that circulated during this outbreak is resistant to streptomycin resulting from a spontaneous point mutation in the 30S ribosomal protein S12 (rpsL) gene. This same mutation causes streptomycin resistance in 2 unrelated Y. pestis strains, one isolated from a fatal PP case in a different region of Madagascar in 1987 and another isolated from a fatal PP case in China in 1996, documenting this mutation has occurred independently at least 3 times in Y. pestis. Laboratory experiments revealed this mutation has no detectable impact on fitness or virulence, and revertants to wild-type are rare in other species containing it, suggesting Y. pestis strains containing it could persist in the environment. Conclusions Unique antimicrobial resistant (AMR) strains of Y. pestis continue to arise in Madagascar and can be transmitted during PP outbreaks. [ABSTRACT FROM AUTHOR]

Abstract Background Francisella tularensis, the causative agent of tularemia, displays subspecies-specific differences in virulence, geographic distribution, and genetic diversity. F. tularensis subsp. holarctica is widely distributed throughout the Northern Hemisphere. In Europe, F. tularensis subsp. holarctica isolates have largely been assigned to two phylogenetic groups that have specific geographic distributions. Most isolates from Western Europe are assigned to the B.Br.FTNF002-00 group, whereas most isolates from Eastern Europe are assigned to numerous lineages within the B.Br.013 group. The eastern geographic extent of the B.Br.013 group is currently unknown due to a lack of phylogenetic knowledge about populations at the European/Asian juncture and in Asia. In this study, we address this knowledge gap by describing the phylogenetic structure of F. tularensis subsp. holarctica isolates from the country of Georgia, and by placing these isolates into a global phylogeographic context. Results We identified a new genetic lineage of F. tularensis subsp. holarctica from Georgia that belongs to the B.Br.013 group. This new lineage is genetically and geographically distinct from lineages previously described from the B.Br.013 group from Central-Eastern Europe. Importantly, this new lineage is basal within the B.Br.013 group, indicating the Georgian lineage diverged before the diversification of the other known B.Br.013 lineages. Although two isolates from the Georgian lineage were collected nearby in the Ukrainian region of Crimea, all other global isolates assigned to this lineage were collected in Georgia. This restricted geographic distribution, as well as the high levels of genetic diversity within the lineage, is consistent with a relatively older origin and localized differentiation. Conclusions We identified a new lineage of F. tularensis subsp. holarctica from Georgia that appears to have an older origin than any other diversified lineages previously described from the B.Br.013 group. This finding suggests that additional phylogenetic studies of F. tularensis subsp. holarctica populations in Eastern Europe and Asia have the potential to yield important new insights into the evolutionary history and phylogeography of this broadly dispersed F. tularensis subspecies.

Abstract Background Francisella tularensis is the etiologic agent of tularemia and is classified as a select agent by the Centers for Disease Control and Prevention. Currently four known subspecies of F. tularensis that differ in virulence and geographical distribution are recognized:tularensis (type A), holarctica (type B), mediasiatica, and novicida. Because of the Select Agent status and differences in virulence and geographical location, the molecular analysis of any clinical case of tularemia is of particular interest. We analyzed an unusual Francisella clinical isolate from a human infection in Arizona using multiple DNA-based approaches. Findings We report that the isolate is F. tularensis subsp. novicida, a subspecies that is rarely isolated. Conclusion The rarity of this novicida subspecies in clinical settings makes each case study important for our understanding of its role in disease and its genetic relationship with other F. tularensis subspecies.

Yersinia pestis was introduced to Brazil during the third plague pandemic and currently exists in several recognized foci. There is currently limited available phylogeographic data regarding Y. pestis in Brazil. We generated whole genome sequences for 411 Y. pestis strains from six Brazilian foci to investigate the phylogeography of Y. pestis in Brazil; these strains were isolated from 1966 to 1997. All 411 strains were assigned to a single monophyletic clade within the 1.ORI population, indicating a single Y. pestis introduction was responsible for the successful establishment of endemic foci in Brazil. There was a moderate level of genomic diversity but little population structure among the 411 Brazilian Y. pestis strains, consistent with a radial expansion wherein Y. pestis spread rapidly from the coast to the interior of Brazil and became ecologically established. Overall, there were no strong spatial or temporal patterns among the Brazilian strains. However, strains from the same focus tended to be more closely related and strains isolated from foci closer to the coast tended to fall in more basal positions in the whole genome phylogeny than strains from more interior foci. Overall, the patterns observed in Brazil are similar to other locations affected during the 3rd plague pandemic such as in North America and Madagascar. [ABSTRACT FROM AUTHOR]

Yersinia pestis was introduced to North America around 1900 and leads to nearly 100% mortality in prairie dog ( Cynomys spp.) colonies during epizootic events, which suggests this pathogen may exert a strong selective force. We characterized genetic diversity at an MHC class II locus ( DRB1) in Gunnison's prairie dog ( C. gunnisoni) and quantified population genetic structure at the DRB1 versus 12 microsatellite loci in three large Arizona colonies. Two colonies, Seligman ( SE) and Espee Ranch ( ES), have experienced multiple plague-related die-offs in recent years, whereas plague has never been documented at Aubrey Valley ( AV). We found fairly low allelic diversity at the DRB1 locus, with one allele ( DRB1*01) at high frequency (0.67-0.87) in all colonies. Two other DRB1 alleles appear to be trans-species polymorphisms shared with the black-tailed prairie dog ( C. ludovicianus), indicating that these alleles have been maintained across evolutionary time frames. Estimates of genetic differentiation were generally lower at the MHC locus ( FST = 0.033) than at microsatellite markers ( FST = 0.098). The reduced differentiation at DRB1 may indicate that selection has been important for shaping variation at MHC loci, regardless of the presence or absence of plague in recent decades. However, genetic drift has probably also influenced the DRB1 locus because its level of differentiation was not different from that of microsatellites in an FST outlier analysis. We then compared specific MHC alleles to plague survivorship in 60 C. gunnisoni that had been experimentally infected with Y. pestis. We found that survival was greater in individuals that carried at least one copy of the most common allele ( DRB1*01) compared to those that did not (60% vs. 20%). Although the sample sizes of these two groups were unbalanced, this result suggests the possibility that this MHC class II locus, or a nearby linked gene, could play a role in plague survival. [ABSTRACT FROM AUTHOR]

Sequence analyses and subtyping of Bacillus anthracis strains from Georgia reveal a single distinct lineage (Aust94) that is ecologically established. Phylogeographic analysis and comparisons to a global collection reveals a clade that is mostly restricted to Georgia. Within this clade, many groups are found around the country, however at least one subclade is only found in the eastern part. This pattern suggests that dispersal into and out of Georgia has been rare and despite historical dispersion within the country, for at least for one lineage, current spread is limited. [ABSTRACT FROM AUTHOR]

An increased incidence of retinopathy of prematurity (ROP) parallels the increased incidence of viable births at earlier gestational ages. However, advancements in laser therapy can treat ROP and ultimately prevent blindness. This paper describes the development, implementation, and evaluation of a tool that consistently documents ROP assessments by medical staff, as well as pertinent medical history necessary to safely manage this critical population. The assessment tool was designed for an outpatient ophthalmology clinic. The outpatient population included all infants delivered at or transferred to the neonatal intensive care unit of a large university hospital located in the Midwestern United States. The infants were considered at risk for ROP if they weighed less than 1500 grams or if they had a gestational age of less than or equal to 34 weeks. At any given time, the outpatient clinic manages from 50 to 70 infants. Implementation of the tool increased consistency in documentation by medical staff and guided the initial assessment for nursing and technical staff members.