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Tularemia, caused by the bacterium Francisella tularensis, where F. tularensis subspecies holarctica has long been the cause of endemic disease in parts of northern Sweden. Despite this, our understanding of the natural life-cycle of the organism is still limited. During three years, we collected surface water samples (n = 341) and sediment samples (n = 245) in two areas in Sweden with endemic tularemia. Real-time PCR screening demonstrated the presence of F. tularenis lpnA sequences in 108 (32%) and 48 (20%) of the samples, respectively. The 16S rRNA sequences from those samples all grouped to the species F. tularensis. Analysis of the FtM19InDel region of lpnA-positive samples from selected sampling points confirmed the presence of F. tularensis subspecies holarctica-specific sequences. These sequences were detected in water sampled during both outbreak and nonoutbreak years. Our results indicate that diverse F. tularensis-like organisms, including F. tularensis subsp. holarctica, persist in natural waters and sediments in the investigated areas with endemic tularemia. [ABSTRACT FROM AUTHOR]

Abstract After 27 years with no detected cases, an outbreak of anthrax occurred in a beef cattle herd in the south of Sweden. The outbreak was unusual as it occurred in winter, in animals not exposed to meat-and-bone meal, in a non-endemic country. The affected herd consisted of 90 animals, including calves and young stock. The animals were kept in a barn on deep straw bedding and fed only roughage. Seven animals died during 10 days, with no typical previous clinical signs except fever. The carcasses were reportedly normal in appearance, particularly as regards rigor mortis, bleeding and coagulation of the blood. Subsequently, three more animals died and anthrax was suspected at necropsy and confirmed by culture and PCR on blood samples. The isolated strain was susceptible to tetracycline, ciprofloxacin and ampicillin. Subtyping by MLVA showed the strain to cluster with isolates in the A lineage of Bacillus anthracis. Environmental samples from the holding were all negative except for two soil samples taken from a spot where infected carcasses had been kept until they were picked up for transport. The most likely source of the infection was concluded to be contaminated roughage, although this could not be substantiated by laboratory analysis. The suspected feed was mixed with soil and dust and originated from fields where flooding occurred the previous year, followed by a dry summer with a very low water level in the river allowing for the harvesting on soil usually not exposed. In the early 1900s, animal carcasses are said to have been dumped in this river during anthrax outbreaks and it is most likely that some anthrax spores could remain in the area. The case indicates that untypical cases in non-endemic areas may be missed to a larger extent than previously thought. Field tests allowing a preliminary risk assessment of animal carcasses would be helpful for increased sensitivity of detection and prevention of further exposure to the causative agent.

Francisella tularensis , the causative agent of the zoonotic disease tularemia, can cause seasonal outbreaks of acute febrile illness in humans with disease peaks in late summer to autumn. Interestingly, its mechanisms for environmental persistence between outbreaks are poorly understood. One hypothesis is that F. tularensis forms biofilms in aquatic environments. We utilized two fully virulent wild-type strains: FSC200 ( Francisella tularensis subsp. holarctica ) and Schu S4 ( Francisella tularensis subsp. tularensis ) and three control strains, the attenuated live vaccine strain (LVS; F. tularensis subsp. holarctica ), a Schu S4 Δ wbtI mutant that is documented to form biofilms, and the low-virulence strain U112 of the closely related species Francisella novicida Strains were incubated in saline solution (0.9% NaCl) microcosms for 24 weeks at both 4°C and 20°C, whereupon viability and biofilm formation were measured. These temperatures were selected to approximate winter and summer temperatures of fresh water in Scandinavia, respectively. U112 and Schu S4 Δ wbtI formed biofilms, but F. tularensis strains FSC200 and Schu S4 and the LVS did not. All strains exhibited prolonged viability at 4°C compared to 20°C. U112 and FSC200 displayed remarkable long-term persistence at 4°C, with only 1- and 2-fold log reductions, respectively, of viable cells after 24 weeks. Schu S4 exhibited lower survival, yielding no viable cells by week 20. At 24 weeks, cells from FSC200, but not from Schu S4, were still fully virulent in mice. Taken together, these results demonstrate biofilm-independent, long-term survival of pathogenic F. tularensis subsp. holarctica in conditions that mimic overwinter survival in aquatic environments. IMPORTANCE Tularemia, a disease caused by the environmental bacterium Francisella tularensis , is characterized by acute febrile illness. F. tularensis is highly infectious: as few as 10 organisms can cause human disease. Tularemia is not known to be spread from person to person. Rather, all human infections are independently acquired from the environment via the bite of blood-feeding arthropods, ingestion of infected food or water, or inhalation of aerosolized bacteria. Despite the environmental origins of human disease events, the ecological factors governing the long-term persistence of F. tularensis in nature between seasonal human outbreaks are poorly understood. The significance of our research is in identifying conditions that promote long-term survival of fully virulent F. tularensis outside a mammalian host or insect vector. These conditions are similar to those found in natural aquatic environments in winter and provide important new insights on how F. tularensis may persist long-term in the environment., (Copyright © 2021 Golovliov et al.)

In recent years, an increasing diversity of species has been recognized within the family Francisellaceae . Unfortunately, novel isolates are sometimes misnamed in initial publications or multiple sources propose different nomenclature for genetically highly similar isolates. Thus, unstructured and occasionally incorrect information can lead to confusion in the scientific community. Historically, detection of Francisella tularensis in environmental samples has been challenging due to the considerable and unknown genetic diversity within the family, which can result in false positive results. We have assembled a comprehensive collection of genome sequences representing most known Francisellaceae species/strains and restructured them according to a taxonomy that is based on phylogenetic structure. From this structured dataset, we identified a small number of genomic regions unique to F. tularensis that are putatively suitable for specific detection of this pathogen in environmental samples. We designed and validated specific PCR assays based on these genetic regions that can be used for the detection of F. tularensis in environmental samples, such as water and air filters.

Here, we report the complete genome sequence of Francisella tularensis subsp. holarctica strain A271_1, isolated from a Eurasian beaver ( Castor fiber ) in 2012 in the Berlin/Brandenburg region, Germany., (Copyright © 2020 Sundell et al.)

Background: Blood donor haemoglobin concentration (Hb) is commonly measured from a skin-prick sample. However, the skin-prick sample is prone to preanalytical error and variation, which may lead to false deferrals due to low Hb., Study Design and Methods: We assessed the efficacy of two second-line screening models for the evaluation of blood donors failing the initial skin-prick test. In the venous model (n = 305), Hb was measured from a venous sample at the donation site. In the skin-prick model (n = 331), two additional skin-prick samples were measured. All on-site Hb measurements were performed with HemoCue Hb201+ (HemoCue AB) point-of-care (POC) device. Hb in the venous samples was later also determined with a hematology analyzer (Sysmex XN, Sysmex Co.) to obtain the donor's correct Hb. A questionnaire evaluated Blood Service nurses' preferences regarding Hb assessment., Results: Significantly less donors were deferred from donation with venous model (40%) than with skin-prick model (51%; chi-square test P = 0·004). Only two donors (0·7%) were incorrectly accepted in the venous model. Further, Blood Service nurses preferred venous model over skin-prick model. After the study, the venous model was implemented nationwide, and in the first two months after implementation, the deferral rate due to low Hb decreased from 2·7% to 1·9%., Conclusion: A venous sample for blood donor Hb second-line screening significantly decreased low Hb deferrals compared to repeated skin-prick testing without compromising donor safety. Valuable donations can be recovered by implementing a practical second-line screening model based on venous sampling., (© 2020 International Society of Blood Transfusion.)

Microbial source tracking (MST) analysis is essential to identifying and mitigating the fecal pollution of water resources. The signature-based MST method uses a library of sequences to identify contaminants based on operational taxonomic units (OTUs) that are unique to a certain source. However, no clear guidelines for how to incorporate OTU overlap or natural variation in the raw water bacterial community into MST analyses exist. We investigated how the inclusion of bacterial overlap between sources in the library affects source prediction accuracy. To achieve this, large-scale sampling - including feces from seven species, raw sewage, and raw water samples from water treatment plants - was followed by 16S rRNA amplicon sequencing. The MST library was defined using three settings: (i) no raw water communities represented; (ii) raw water communities selected through clustering analysis; and (iii) local water communities collected across consecutive years. The results suggest that incorporating either the local background or representative bacterial composition improves MST analyses, as the results were positively correlated to measured levels of fecal indicator bacteria and the accuracy at which OTUs were assigned to the correct contamination source increased fourfold. Using the proportion of OTUs with high source origin probability, underpinning a contaminating signal, is a solid foundation in a framework for further deciphering and comparing contaminating signals derived in signature-based MST approaches. In conclusion, incorporating background bacterial composition of water in MST can improve mitigation efforts for minimizing the spread of pathogenic and antibiotic resistant bacteria into essential freshwater resources.

Background: Blood transfusion through the intraosseous route is gaining popularity in emergency medicine. Pretransfusion peripheral blood (PB) samples are usually not available in these patients, leading to discrepancies in blood group typing and a possible delay in transferring to group-specific blood products. The aim of this study was to assess the feasibility of ABO and D typing and red blood cell alloantibody screening in marrow (BM) samples., Study Design and Methods: Direct and reverse ABO typing, D typing, and a two-cell alloantibody screen were performed in EDTA-anticoagulated BM samples with standard manual column agglutination techniques. EDTA-anticoagulated PB samples were used as controls., Results: The mean age of the study subjects (n = 71) was 47 years (range, 1-82 years). All ABO groups and both D+ and D- types were represented. In all subjects, concordant results were observed for all analyses in BM and PB samples. In 15 (21%) of the samples, a discrepancy of one reaction strength step (1+) was observed in at least one of the analyses (Cohen's weighted κ = 0.993); this did not affect interpretation of the results., Conclusion: Blood group typing and alloantibody screening are feasible in BM samples, providing proof-of-concept that intraosseous samples for blood group serologic analyses can be collected from emergency patients before intraosseous blood transfusion. This will enable a timely transfer to group-specific blood products and enable conservation of the valuable universal-donor blood products., (© 2018 AABB.)

Background: Low hemoglobin (Hb) is the most common reason for temporary blood donor deferral. However, factors that affect Hb measurement may not portray donor health but reflect external circumstances., Study Design and Methods: The effects of season, time of day, donor age, ABO, and D on capillary blood Hb level (cHb) and low Hb deferral were analyzed in 1,396,645 donor registrations from the years 2010 to 2014 in a national blood bank., Results: cHb was lower in the summer (July mean 154.1 g/L in men, 139.6 g/L in women) and in the evening (7 pm mean 153.8 g/L in men, 138.9 g/L in women) than in the winter (January mean 156.9 g/L in men, 141.8 g/L in women) and in the morning (11 am mean 157.2 g/L in men, 142.8 g/L in women; all p < 0.0001). This affected donor deferral due to low Hb, with 7.8% donors deferred in July at 7 pm and 1.6% deferred in January at 11 am (p < 0.0001). With age, cHb increased in women and decreased in men. The lowest cHb was observed in blood group A (mean 154.9 g/L in men, 140.3 g/L in women) and the highest in blood group B (mean 156.6 g/L in men, 141.5 g/L in women). D had no practically significant effect on cHb., Conclusion: External factors, which do not reflect donor health, affect cHb and donor deferral due to low Hb. These factors should be considered when donor eligibility guidelines and procedures are developed., (© 2016 AABB.)

Purpose: To describe content validity, concurrent validity, sensitivity to change, internal consistency and the outcome distribution of the Patient Specific Functional Scale (PSFS) in patients with proximal humeral fracture., Method: Fifty-three patients with proximal humeral fracture treated conservatively or surgically with plate and screw or intramedullary nail were recruited 6 weeks (±1 week) post-trauma or post-surgery. The following assessments were used: the PSFS, patient global score, shoulder function assessment, grip strength and Western Ontario Osteoarthritis of the shoulder Index (WOOS), before start of (n = 53) and after (n = 22) 2-3 months of group rehabilitation., Results: In total, 96% of the activities stated in the PSFS was classified in the International Classification of Functioning, Disability and Health activity component and 62% were found in the WOOS. Correlations between measures were low. The PSFS was highly sensitive to change to a period of group rehabilitation. All questions of the PSFS contributed to the total score. Both floor and ceiling effects could be noted., Conclusion: The PSFS shows satisfying measurement properties and may be a useful complement in the evaluation of individual changes during a period of rehabilitation after proximal humeral fracture., Implications for Rehabilitation: The PSFS assesses on activity level in patients with proximal humeral fracture. The PSFS is sensitive to change for group rehabilitation after humeral fracture. The PSFS can be useful for goal-setting, motivating and individually tailoring rehabilitation activities. The PSFS should be used in addition to specific measures of body functions and general health.

We present the complete genome sequence of Francisella guangzhouensis strain 08HL01032(T), which consists of one chromosome (1,658,482 bp) and one plasmid (3,045 bp) with G+C contents of 32.0% and 28.7%, respectively., (Copyright © 2015 Svensson et al.)

Mosquitoes are thought to function as mechanical vectors of Francisella tularensis subspecies holarctica (F. t. holarctica) causing tularemia in humans. We investigated the clinical relevance of transstadially maintained F. t. holarctica in mosquitoes. Aedes egypti larvae exposed to a fully virulent F. t. holarctica strain for 24 hours, were allowed to develop into adults when they were individually homogenized. Approximately 24% of the homogenates tested positive for F. t. DNA in PCR. Mice injected with the mosquito homogenates acquired tularemia within 5 days. This novel finding demonstrates the possibility of transmission of bacteria by adult mosquitoes having acquired the pathogen from their aquatic larval habitats.

Brucellosis is a highly infectious zoonotic disease but rare in Sweden. Nonetheless, an outbreak of canine brucellosis caused by an infected dog imported to Sweden was verified in 2013. In total 25 dogs were tested at least duplicated by the following approaches: real-time PCR for the detection of Brucella canis, a Brucella genus-specific real-time PCR, selective cultivation, and microscopic examination. The whole genome of B. canis strain SVA13 was analysed regarding genetic markers for epidemiological examination. The genome of an intact prophage of Roseobacter was detected in B. canis strain SVA13 with whole genome sequence prophage analysis (WGS-PA). It was shown that the prophage gene content in the American, African and European isolates differs remarkably from the Asian strains. The prophage sequences in Brucella may therefore serve of use as genetic markers in epidemiological investigations. Phage DNA fragments were also detected in clustered, regularly interspaced short palindromic repeats (CRISPR) in the genome of strain SVA13. In addition to the recommendations for genetic markers in Brucella outbreak tracing, our paper reports a validated two-step stand-alone real-time PCR for the detection of B. canis and its first successful use in an outbreak investigation., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A strain of Francisella endociliophora was isolated from a laboratory culture of the marine ciliate Euplotes raikovi. Here, we report the complete genome sequence of the bacterial strain FSC1006 (Francisella Strain Collection, Swedish Defence Research Agency, Umeå, Sweden)., (Copyright © 2014 Sjödin et al.)

With the aim of developing quantitative PCR methods for the detection and differentiation of Brucella species, the genomes of Brucella ceti, Brucella inopinata, Brucella netotomae, and Brucella suis biovar 4 were sequenced and analyzed., (Copyright © 2014 Wahab et al.)