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Background: In Kazakhstan, a live plague vaccine EV 76 NIIEG has been used for plague prophylaxis since the mid-1930s. Vaccination is administered yearly among people living in plague-enzootic areas. Similar practices are used in other former Soviet Union countries. Yet, to this day, the effectiveness period of the vaccine is unknown. It is also not clear how different factors can affect the effectiveness of the vaccine over time. Methods: We surveyed changes in antibody levels specific for F1 antigens of Yersinia pestis among vaccinated people 4, 8, and 12 months post- vaccination. Blood samples were taken from the participants of the study for producing sera, which was later analyzed using indirect hemagglutination reaction with antigenic erythrocyte assay (micromethod) for identifying antibodies to F1 Y.pestis. Results: In first-time-receivers of the plague vaccine, antibody titer reached the highest level of antibody that represents a conditionally protective titer after 4 months, dropped drastically after 8 months, and dropped again after 12 months. Similar results were obtained among those who have been vaccinated previously. However, in that group, the percentage of people with a level of antibody that represents a conditionally protective titer remained statistically significant even after 8 and 12 months. Conclusion: Based on the results of this study, we recommend initiating vaccination campaigns for the medical and veterinary staff, as well as the general population four months prior to the springtime epizootics of plague among wild rodents. [ABSTRACT FROM AUTHOR]

Hantaan virus (HTNV) and Puumala virus (PUUV) are rodent-borne hantaviruses that are the primary causes of hemorrhagic fever with renal syndrome (HFRS) in Europe and Asia. The development of well characterized animal models of HTNV and PUUV infection is critical for the evaluation and the potential licensure of HFRS vaccines and therapeutics. In this study we present three animal models of HTNV infection (hamster, ferret and marmoset), and two animal models of PUUV infection (hamster, ferret). Infection of hamsters with a ~3 times the infectious dose 99% (ID99) of HTNV by the intramuscular and ~1 ID99 of HTNV by the intranasal route leads to a persistent asymptomatic infection, characterized by sporadic viremia and high levels of viral genome in the lung, brain and kidney. In contrast, infection of hamsters with ~2 ID99 of PUUV by the intramuscular or ~1 ID99 of PUUV by the intranasal route leads to seroconversion with no detectable viremia, and a transient detection of viral genome. Infection of ferrets with a high dose of either HTNV or PUUV by the intramuscular route leads to seroconversion and gradual weight loss, though kidney function remained unimpaired and serum viremia and viral dissemination to organs was not detected. In marmosets a 1,000 PFU HTNV intramuscular challenge led to robust seroconversion and neutralizing antibody production. Similarly to the ferret model of HTNV infection, no renal impairment, serum viremia or viral dissemination to organs was detected in marmosets. This is the first report of hantavirus infection in ferrets and marmosets. [ABSTRACT FROM AUTHOR]

Introduction: There is evidence that greater neighbourhood walkability (i.e., neighbourhoods with more amenities and well-connected streets) is associated with higher levels of total walking in Europe and in Asia, but it remains unclear if this association holds in the Canadian context and in chronic disease populations. We examined the relationships of different walkability measures to biosensor-assessed total walking (i.e., steps/day) in adults with type 2 diabetes living in Montreal (QC, Canada). Materials and Methods: Participants (60.5±10.4 years; 48.1% women) were recruited through McGill University-affiliated clinics (June 2006 to May 2008). Steps/day were assessed once per season for one year with pedometers. Neighbourhood walkability was evaluated through participant reports, in-field audits, Geographic Information Systems (GIS)-derived measures, and the Walk Score®. Relationships between walkability and daily steps were estimated using Bayesian longitudinal hierarchical linear regression models (n = 131). Results: Participants who reported living in the most compared to the least walkable neighbourhoods completed 1345 more steps/day (95% Credible Interval: 718, 1976; Quartiles 4 versus 1). Those living in the most compared to the least walkable neighbourhoods (based on GIS-derived walkability) completed 606 more steps per day (95% CrI: 8, 1203). No statistically significant associations with steps were observed for audit-assessed walkability or the Walk Score®. Conclusions: Adults with type 2 diabetes who perceived their neighbourhoods as more walkable accumulated more daily steps. This suggests that knowledge of local neighborhood features that enhance walking is a meaningful predictor of higher levels of walking and an important component of neighbourhood walkability. [ABSTRACT FROM AUTHOR]