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Opportunistic fungal infections, such as those caused by Cryptococcus neoformans, are common causes of death and illness among persons with compromised immune systems. C. gattii is a related fungus that [...]

West Nile virus (WNV) is a vector-borne flavivirus that is transmitted in an enzootic cycle between birds by mosquitoes; incidental transmission to humans occurs during periods of intense amplification, typically [...]

The characterization of Cryptococcus gattii isolates from tree surfaces, soils, air, freshwater, and seawater indicates extensive colonization within British Columbia, confirming the expansion of the ecological niche of Cryptococcus gattii to temperate regions and acidic soil.

Cryptococcus gattii, emergent on Vancouver Island, British Columbia (BC), Canada, in 1999, was detected during 2003-2005 in 3 persons and 8 animals that did not travel to Vancouver Island during [...]

Recent Cryptococcus gattii infections in humans and animals without travel history to Vancouver Island, as well as environmental isolations of the organism in other areas of the Pacific Northwest, led [...]

Abstract Background Illicit drug overdose deaths (IDD) relate to individual drug dose and context of use, including use with other drugs and alcohol. IDD peaked in British Columbia (BC) in 1998 with 417 deaths, and continues to be a public health problem. The objective of this study was to examine IDD in 2006 in BC by place of residence, injury and death, decedents' age and sex and substances identified. Methods IDD data was obtained through the BC Coroners Office and entered into SPSS (version 14). Fisher's exact and Pearson's χ2 were used for categorical data; Mann-Whitney U-test for continuous variables. Rates were calculated using 2006 population estimates. Results We identified 223 IDD in BC; 54 (24%) occurred in Vancouver. Vancouver decedents (compared to those occurring outside Vancouver) were older (mean age 43.9 vs. 39.2 years; p < 0.01) and more likely to be male (90.7% vs. 77.5%; p = 0.03). Provincially Aboriginal ethnicity was reported for 19 deaths; 13 (30.2%) of 43 females and 6 (3.3%) of 180 males (p = < 0.001). Cocaine was identified in 80.3%, opiates 59.6%, methadone 13.9%, methamphetamine/amphetamine 6.3%, and alcohol in 22.9% of deaths. Poly-substance use was common, 2 substances were identified in 43.8% and 3 or more in 34.5% of deaths. Opiates were more frequently identified in Vancouver compared to outside Vancouver (74.1% vs. 55.0%) p = 0.015. Conclusion Collaboration with the Coroner's office allowed us to analyze IDD in detail including place of death; cocaine, opiates and poly-substance use were commonly identified. Poly-substance use should be explored further to inform public health interventions.

Abstract Background The BC Harm Reduction Strategies and Services (HRSS) policy states that each health authority (HA) and their community partners will provide a full range of harm reduction (HR) services to their jurisdictions and these HR products should be available to all who need them regardless of where they live and choice of drug. Preliminary analysis revealed wide variations between and within HAs. Methods The objective of this study is to analyze distribution of HR products by site using Geographic Information Systems (GIS) and to investigate the range, adequacy and methods of HR product distribution using qualitative interviews. The BC Centre for Disease Control pharmacy database tracks HR supplies distributed to health units and community agencies. Additionally, eleven face-to-face interviews were conducted in eight mainland BC communities using an open-ended questionnaire. Results There is evidence in BC that HR supplies are not equally available throughout the province. There are variations within jurisdictions in how HR supplies are distributed, adequacy of current HR products, collection of used needles, alternative uses of supplies and community attitudes towards HR. GIS illustrates where HR supplies are ordered but with secondary distribution, true reach and availability of supplies cannot be determined. Conclusion Currently, a consultant is employed to develop a 'best practice' document; relevant health files, standard training and protocols within HAs are also being developed. There is a need to enhance the profile and availability of culturally appropriate HR services for Aboriginal populations. Distribution of crackpipe mouthpieces is being investigated.

Abstract Background The objective of this evaluation was to determine whether reports of dead corvid sightings and submissions of dead corvids for West Nile virus testing were representative of true corvid mortality in British Columbia in 2004, a year with no West Nile virus activity, in order to ensure the system was accurately describing corvid mortality rather than reflecting regional differences in surveillance methods. Results Local Health Areas reported 0–159 (median = 3) dead corvid sightings and 0–209 (median = 5) submissions for West Nile virus testing. The expected numbers of dead corvid sightings and submissions for testing from each Local Health Area were 0–232 (median = 3) and 0–258 (median = 4), respectively. Twelve Local Health Areas reported significantly fewer sightings than expected; 21 reported significantly more. Eleven Local Health Areas submitted significantly fewer corvids than expected; 26 submitted significantly more. Conclusion Some Local Health Areas were over-represented and others under-represented in terms of corvid West Nile virus surveillance indicators. Recommendations were made to improve the representativeness of corvid surveillance data. Geographic analysis can be used to evaluate the representativeness of surveillance systems and result in improvements to surveillance.

Abstract Background West Nile virus (WNv) has recently emerged as a health threat to the North American population. After the initial disease outbreak in New York City in 1999, WNv has spread widely and quickly across North America to every contiguous American state and Canadian province, with the exceptions of British Columbia (BC), Prince Edward Island and Newfoundland. In this study we develop models of mosquito population dynamics for Culex tarsalis and C. pipiens, and create a spatial risk assessment of WNv prior to its arrival in BC by creating a raster-based mosquito abundance model using basic geographic and temperature data. Among the parameters included in the model are spatial factors determined from the locations of BC Centre for Disease Control mosquito traps (e.g., distance of the trap from the closest wetland or lake), while other parameters were obtained from the literature. Factors not considered in the current assessment but which could influence the results are also discussed. Results Since the model performs much better for C. tarsalis than for C. pipiens, the risk assessment is carried out using the output of C. tarsalis model. The result of the spatially-explicit mosquito abundance model indicates that the Okanagan Valley, the Thompson Region, Greater Vancouver, the Fraser Valley and southeastern Vancouver Island have the highest potential abundance of the mosquitoes. After including human population data, Greater Vancouver, due to its high population density, increases in significance relative to the other areas. Conclusion Creating a raster-based mosquito abundance map enabled us to quantitatively evaluate WNv risk throughout BC and to identify the areas of greatest potential risk, prior to WNv introduction. In producing the map important gaps in our knowledge related to mosquito ecology in BC were identified, as well, it became evident that increased efforts in bird and mosquito surveillance are required if more accurate models and maps are to be produced. Access to real time climatic data is the key for developing a real time early warning system for forecasting vector borne disease outbreaks, while including social factors is important when producing a detailed assessment in urban areas.

Background: Tick-borne relapsing fever is one of the oldest tick-borne diseases identified in British Columbia. The causative agent is the spirochete Borrelia hermsii, which is transmitted to humans by the night-feeding soft-shelled tick Ornithodoros hermsi found in southeastern British Columbia and the northwestern United States. The identification of this illness is made difficult by the fact that tick-borne relapsing fever is not a reportable illness in BC and laboratory diagnosis can be challenging. The innocuous feeding pattern of the vector tick means bites can go unnoticed, while the typical 7-day delay in symptoms means patients often do not become ill until after they have left a disease-endemic area where physicians are more likely to recognize the illness. Identification and treatment of this illness is important because it can cause long-term sequelae, including cardiac and renal disturbances, peripheral nerve disturbances, ophthalmitis, and complications during pregnancy. A report on a 10-year review of cases in BC was proposed to alert physicians to the presence of this infectious disease and explain how to submit blood samples for testing to the BC Centre for Disease Control Public Health Laboratory. Methods: From 2006 to 2015, the BC Centre for Disease Control Public Health Laboratory received 112 samples from 100 patients suspected to have tick-borne relapsing fever. These samples were analyzed using dark field microscopy, immunofluorescence assay, western blot testing, and polymerase chain reaction assay. A review of the laboratory findings was conducted and the diagnostic challenges and sample requirements were considered. Results: The 100 patients (57 male, 43 female) whose 112 samples were analyzed during the review period ranged in age from 6 to 83 years, and most (67%) were either young or middle-aged adults (20 to 60 years). Of these patients, 19 tested positive for B. hermsii (12 female, 7 male). Except for 2009 and 2014, at least one case of tick-borne relapsing fever was identified each year, with the top year being 2007 (seven cases). Most of the positive cases were associated with the Thompson-Okanagan region. Polymerase chain reaction assay and Giemsa stain testing yielded the highest proportion of positive results (4 of 11 samples) followed by immunofluorescence assay for IgG antibodies (19 of 109). Conclusions: The high proportion of positive results (19%) may be due to the submission of mainly very characteristic samples received from an endemic area. Many physicians may not be aware of the presence of B. hermsii tick-borne relapsing fever in BC and therefore do not request testing. Physicians should note that patients are unlikely to report a painless tick bite received during sleep and that the key symptom is a sudden, high fever (39.2 °C or higher) that follows an incubation period of approximately 7 days and lasts 3 to 7 days. An asymptomatic period of 7 days is then followed by an average of two relapses. General infections considered in the differential diagnosis should include salmonellosis, bartonellosis, tularemia, and leptospirosis. Patients should also be asked about foreign travel to rule out a range of other infections such as malaria, kala azar, yellow fever, and sand fly fever. Blood samples for identifying the causative agent for a recurrent fever should be collected while the patient is febrile and prior to initiation of antibiotic therapy. The appropriate samples are 7 mL of blood in a red-top serum separator tube for serology and 7 mL of blood in an EDTA tube for Giemsa staining and polymerase chain reaction assay. Patients diagnosed with tick-borne relapsing fever have been shown to respond effectively to doxycycline/tetracycline, macrolides such as erythromycin, and penicillin. Approximately one-half of patients will experience some sort of Jarisch-Herxheimer reaction and should be monitored for this. In future, molecular testing, an organized approach to diagnosis, and a greater physician awareness of this illness should allow for more rapid and confident diagnoses and effective treatment of patients with this tick-borne illness. [ABSTRACT FROM AUTHOR]

Vancouver Island, Canada, reports the world's highest incidence of Cryptococcus gattii infection among humans and animals. To identify key biophysical factors modulating environmental concentrations, we evaluated monthly concentrations of C. gatti in air, soil, and trees over a 3-year period. The 2 study datasets were repeatedly measured plots and newly sampled plots. We used hierarchical generalized linear and mixed effect models to determine associations. Climate systematically influenced C. gattii concentrations in all environmental media tested; in soil and on trees, concentrations decreased when temperatures were warmer. Wind may be a key process that transferred C. gattii from soil into air and onto trees. C. gattii results for tree and air samples were more likely to be positive during periods of higher solar radiation. These results improve the understanding of the places and periods with the greatest C. gattii colonization. Refined risk projections may help susceptible persons avoid activities that disturb the topsoil during relatively cool summer days. [ABSTRACT FROM AUTHOR]

Background: Leptospira interrogans is a bacterial zoonosis with a worldwide distribution for which rats (Rattus spp.) are the primary reservoir in urban settings. In order to assess, monitor, and mitigate the risk to humans, it is important to understand the ecology of this pathogen in rats. The objective of this study was to characterize the ecology of L. interrogans in Norway rats (Rattus norvegicus) in an impoverished inner-city neighborhood of Vancouver, Canada. Methodology/Principal Findings: Trapping was performed in 43 city blocks, and one location within the adjacent port, over a 12 month period. Kidney samples were tested for the presence of L. interrogans using PCR and sequencing. A multivariable model was built to predict L. interrogans infection status in individual rats using season and morphometric data (e.g., weight, sex, maturity, condition, etc.) as independent variables. Spatial analysis was undertaken to identify clusters of high and low L. interrogans prevalence. The prevalence of L. interrogans varied remarkably among blocks (0–66.7%), and spatial clusters of both high and low L. interrogans prevalence were identified. In the final cluster-controlled model, characteristics associated with L. interrogans-infection in rats included weight (OR = 1.14, 95% CI = 1.07–1.20), increased internal fat (OR = 2.12, 95% CI = 1.06–4.25), and number of bite wounds (OR = 1.20, 95% CI = 0.96–1.49). Conclusions/Significance: Because L. interrogans prevalence varied with weight, body fat, and bite wounds, this study suggests that social structure and interactions among rats may influence transmission. The prevalence and distribution of L. interrogans in rats was also highly variable even over a short geographic distance. These factors should be considered in future risk management efforts. [ABSTRACT FROM AUTHOR]