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The mechanisms facilitating the relationship between low income and COVID-19 severity have not been partitioned in the presence of SARS-CoV-2 variants of concern (VOC). To address this, we used causal mediation analysis to quantify the possible mediating role infection with VOC has on the relationship between neighbourhood income (exposure) and hospitalisation due to COVID-19 among cases (outcome). A population-based cohort of 65,629 individuals residing in British Columbia, Canada, was divided into three periods of VOC co-circulation in the 2021 calendar year whereby each period included co-circulation of an emerging and an established VOC. Each cohort was subjected to g-formula mediation techniques to decompose the relationship between exposure and outcome into total, direct and indirect effects. In the mediation analysis, the total effects indicated that low income was associated with increased odds of hospitalisation across all periods. Further decomposition of the effects revealed that income is directly and indirectly associated with hospitalisation. The resulting indirect effect through VOC accounted for approximately between 6 and 13% of the total effect of income on hospitalisation. This study underscores, conditional on the analysis, the importance of addressing underlying inequities to mitigate the disproportionate impact on historically marginalised communities by adopting an equity lens as central to pandemic preparedness and response from the onset.
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The outbreak of the severe acute respiratory syndrome coronavirus 2 started in Wuhan, China, towards the end of 2019 and spread worldwide. The rapid spread of the disease can be attributed to many factors including its high infectiousness and the high rate of human mobility around the world. Although travel/movement restrictions and other non-pharmaceutical interventions aimed at controlling the disease spread were put in place during the early stages of the pandemic, these interventions did not stop COVID-19 spread. To better understand the impact of human mobility on the spread of COVID-19 between regions, we propose a hybrid gravity-metapopulation model of COVID-19. Our modeling framework has the flexibility of determining mobility between regions based on the distances between the regions or using data from mobile devices. In addition, our model explicitly incorporates time-dependent human mobility into the disease transmission rate, and has the potential to incorporate other factors that affect disease transmission such as facemasks, physical distancing, contact rates, etc. An important feature of this modeling framework is its ability to independently assess the contribution of each factor to disease transmission. Using a Bayesian hierarchical modeling framework, we calibrate our model to the weekly reported cases of COVID-19 in thirteen local health areas in Metro Vancouver, British Columbia (BC), Canada, from July 2020 to January 2021. We consider two main scenarios in our model calibration: using a fixed distance matrix and time-dependent weekly mobility matrices. We found that the distance matrix provides a better fit to the data, whilst the mobility matrices have the ability to explain the variance in transmission between regions. This result shows that the mobility data provides more information in terms of disease transmission than the distances between the regions.
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COVID-19 , Humanos , COVID-19/epidemiologia , Teorema de Bayes , SARS-CoV-2 , Surtos de Doenças , Colúmbia BritânicaRESUMO
Healthcare worker wellness is foundational to delivering quality care. Yet, healthcare facilities often lack access to healthy and sustainable food overnight and on weekends. Healthy, low-carbon meals were provided free of charge after hours to on-call General Surgery residents at the University of British Columbia and the impact on resident well-being assessed using pre- and post-intervention surveys. Financial and time stress reduced significantly with the provision of meals (P's < .01), while emotional and physical stress levels did not change. Average meal expenses decreased from $33 to $10 (P < .001). Increasing food access on call is an impactful intervention to improve resident health and well-being.
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OBJECTIVE: Health policy and system leaders need to know whether long travel time to a delivery facility adversely affects birth outcomes. In this study, we estimated associations between travel time to delivery and outcomes in low-risk pregnancies. METHODS: This population-based cohort included all singleton births without obstetric comorbidities or intrapartum facility transfers in British Columbia, Canada, from 2012 to 2019. Travel time was measured from maternal residential postal code to delivery facility using road network analysis. We estimated associations between travel time and severe maternal morbidity, stillbirth, pre-term birth, and small-for-gestational age (SGA) and large-for-gestational age (LGA) status using logistic regression, adjusted for confounders (adjusted odds ratios [aORs]). To examine variations in associations between travel time and outcomes by antenatal care utilization, we stratified models by antenatal care categories. RESULTS: Of 232 698 births, 3.8% occurred at a facility ≥60 minutes from the maternal residence. Obesity, adolescent age, substance use, inadequate prenatal care, and low socioeconomic status were more frequent among those traveling farther for delivery. Travel time ≥120 minutes was associated with increased risk of stillbirth (aOR 1.8; 95% CI 1.2-2.8), pre-term birth (aOR 2.3; 95% CI 2.1-2.5), LGA (aOR 1.5; 95% CI 1.4-1.6), and severe maternal morbidity (aOR 1.5; 95% CI 1.2-1.8), but not SGA (aOR 1.0; 95% CI 0.8-1.1), when compared with a travel time of 1-29 minutes. Risk of stillbirth was greatest with inadequate and intensive (adequate plus) antenatal care but persisted for severe maternal morbidity, pre-term birth, and LGA across categories. CONCLUSION: Longer travel time to delivery was associated with increased risk of adverse outcomes in low-risk pregnancies after adjusting for confounding factors. Associations were stronger among those with inadequate antenatal care.
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Complicações na Gravidez , Cuidado Pré-Natal , Adolescente , Colúmbia Britânica/epidemiologia , Feminino , Retardo do Crescimento Fetal , Humanos , Gravidez , Estudos Retrospectivos , Natimorto/epidemiologia , Aumento de PesoRESUMO
"Core areas" of transmission for bacterial sexually transmitted infections have been identified. However, it is unclear whether core areas apply to viral infections, such as hepatitis C virus (HCV). We used geographic mapping and spatial analysis to identify distinct core areas of HCV infection in British Columbia (BC) using the BC Hepatitis Testers Cohort (BC-HTC), 1990-2013. The BC-HTC includes all BC residents tested for HCV (~1.5 million; 1990-2013). Core HCV infection areas were identified spatially and temporally for five time periods (1990-1993, 1994-1998, 1999-2003, 2004-2008 and 2009-2013) through thematic mapping, Kernel Density Estimation, Hotspot analysis and cluster analysis at the Census dissemination area level in ArcGIS and SatScan. HCV infection core areas were consistently identified. HCV core areas expanded from the downtown of major cities in different regions of BC (Metro Vancouver, Vancouver Island, and Northern BC; 1990-1998), to smaller cities in Metro Vancouver and Interior BC (2000 onwards). Statistically significant clusters, or hotspots, were also observed for downtown Vancouver, Northern BC (Prince George) and Vancouver Island from 1990 to 2008 with expansion to other urban areas in Metro Vancouver from 1990-2013. Statistically significant clusters persisted after adjustment for injection drug use, number of HCV tests, age, sex, material and social deprivation. Persistence of areas with high HCV diagnoses rates in Vancouver and Prince George supports the theory of core areas of HCV transmission. Identification of core areas can inform prevention, care and treatment programme interventions and evaluate their impact over time.
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Geografia Médica , Hepatite C/epidemiologia , Análise Espacial , Adulto , Colúmbia Britânica/epidemiologia , Análise por Conglomerados , Estudos de Coortes , Feminino , Hepacivirus , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Abuso de Substâncias por Via IntravenosaRESUMO
BACKGROUND: Spatial clusters of syphilis have been observed within several jurisdictions globally; however, the degree to which they are predicted by the spatial distributions of gay, bisexual, and other men who have sex with men (GBM) and testing remains unknown. We sought to describe the spatial-temporal epidemiology of infectious syphilis and identify associations between neighborhood-level factors and rates of syphilis, in British Columbia, Canada. METHODS: We used ArcGIS to map infectious syphilis cases among men (2005 to 2016), SaTScan to detect areas with significantly elevated rates of syphilis, and spatial regression to identify associations between neighborhood-level factors and rates of syphilis. RESULTS: Five clusters were identified: a core in downtown Vancouver (incidence rate ratio [IRR], 18.0; 2007-2016), 2 clusters adjacent to the core (IRR, 3.3; 2012-2016; and IRR, 2.2; 2013-2016), 1 cluster east of Vancouver (IRR, 2.1; 2013-2016), and 1 cluster in Victoria (IRR, 4.3; 2015-2016). Epidemic curves were synchronized across cluster and noncluster regions. Neighborhood-level GBM population estimates and testing rates were both associated with syphilis rates; however, the spatial distribution of syphilis was not fully explained by either of these factors. CONCLUSIONS: We identified two novel ecologic correlates of the spatial distribution of infectious syphilis-density of GBM and rates of syphilis testing-and found that these factors partially, though not entirely, explained the spatial distribution of clusters. Residual spatial autocorrelation suggests that greater syphilis testing coverage may be needed and low-barrier GBM-affirming testing should be expanded to regions outside the core.
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Epidemias , Características de Residência , Análise Espaço-Temporal , Sífilis/epidemiologia , Adulto , Colúmbia Britânica/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Incidência , Masculino , Comportamento Sexual , Minorias Sexuais e de Gênero/estatística & dados numéricos , Sorodiagnóstico da SífilisRESUMO
BACKGROUND: Climate change is increasing the number and intensity of extreme weather events in many parts of the world. Precipitation extremes have been linked to both outbreaks and sporadic cases of waterborne illness. We have previously shown a link between heavy rain and turbidity to population-level risk of sporadic cryptosporidiosis and giardiasis in a major Canadian urban population. The risk increased with 30 or more dry days in the 60 days preceding the week of extreme rain. The goal of this study was to investigate the change in cryptosporidiosis and giardiasis risk due to climate change, primarily change in extreme precipitation. METHODS: Cases of cryptosporidiosis and giardiasis were extracted from a reportable disease system (1997-2009). We used distributed lag non-linear Poisson regression models and projections of the exposure-outcome relationship to estimate future illness (2020-2099). The climate projections are derived from twelve statistically downscaled regional climate models. Relative Concentration Pathway 8.5 was used to project precipitation derived from daily gridded weather observation data (~ 6 × 10 km resolution) covering the central of three adjacent watersheds serving metropolitan Vancouver for the 2020s, 2040s, 2060s and 2080s. RESULTS: Precipitation is predicted to steadily increase in these watersheds during the wet season (Oct. -Mar.) and decrease in other parts of the year up through the 2080s. More weeks with extreme rain (>90th percentile) are expected. These weeks are predicted to increase the annual rates of cryptosporidiosis and giardiasis by approximately 16% by the 2080s corresponding to an increase of 55-136 additional cases per year depending upon the climate model used. The predicted increase in the number of waterborne illness cases are during the wet months. The range in future projections compared to historical monthly case counts typically differed by 10-20% across climate models but the direction of change was consistent for all models. DISCUSSION: If new water filtration measures had not been implemented in our study area in 2010-2015, the risk of cryptosporidiosis and giardiasis would have been expected to increase with climate change, particularly precipitation changes. In addition to the predicted increase in the frequency and intensity of extreme precipitation events, the frequency and length of wet and dry spells could also affect the risk of waterborne diseases as we observed in the historical period. These findings add to the growing evidence regarding the need to prepare water systems to manage and become resilient to climate change-related health risks.
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Mudança Climática/estatística & dados numéricos , Chuva , Doenças Transmitidas pela Água/epidemiologia , Colúmbia Britânica/epidemiologia , Previsões , Humanos , Incidência , Estações do AnoRESUMO
Cryptococcus gattii emerged on Vancouver Island in 1999 for unknown reasons, causing human and animal fatalities and illness. The apparent emergence of this fungus in another temperate area, this time in the Pacific Northwest, suggests the fungus may have expanded its ecological niche. Yet studies that directly examine the potential roles of climatic and land use changes on C. gattii are still lacking. We aim to summarize the existing global literature on the ecology of C. gattii, with particular focus on the gap in knowledge surrounding the potential effects of climatic and land use changes. We systematically reviewed English peer-reviewed literature on the ecological determinants of C. gattii. We included studies published from January 1970 through June 2016 and identified 56 relevant studies for our review. We identified environmental isolations of C. gattii from 18 countries, spanning 72 separate regions across six continents. Fifty-three tree species were associated with C. gattii, spanning 10 climate classifications and 36 terrestrial ecoregions. No studies directly tested the potential effects of climatic changes (including climatic oscillations and global climate change) on C. gattii, while only one study directly assessed those of land use change. To improve model predictions of current and future distributions of C. gattii, more focus is needed on the potential effects of climatic and land use changes to help decrease the public health risk. The apparent emergence of C. gattii in British Columbia is also an opportunity to explore the factors behind emerging infectious diseases in Canada and elsewhere.
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Criptococose/epidemiologia , Cryptococcus gattii/fisiologia , Meio Ambiente , Microbiologia do Ar , Animais , Colúmbia Britânica/epidemiologia , Mudança Climática , Cryptococcus gattii/classificação , Cryptococcus gattii/isolamento & purificação , Ecossistema , Humanos , Microbiologia do SoloRESUMO
Drinking water related infections are expected to increase in the future due to climate change. Understanding the current links between these infections and environmental factors is vital to understand and reduce the future burden of illness. We investigated the relationship between weekly reported cryptosporidiosis and giardiasis (n = 7,422), extreme precipitation (>90th percentile), drinking water turbidity, and preceding dry periods in a drinking water system located in greater Vancouver, British Columbia, Canada (1997-2009) using distributed lag non-linear Poisson regression models adjusted for seasonality, secular trend, and the effect of holidays on reporting. We found a significant increase in cryptosporidiosis and giardiasis 4-6 weeks after extreme precipitation. The effect was greater following a dry period. Similarly, extreme precipitation led to significantly increased turbidity only after prolonged dry periods. Our results suggest that the risk of cryptosporidiosis and giardiasis increases with extreme precipitation, and that the effects are more pronounced after a prolonged dry period. Given that extreme precipitation events are expected to increase with climate change, it is important to further understand the risks from these events, develop planning tools, and build resilience to these future risks.
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Mudança Climática , Criptosporidiose/epidemiologia , Giardíase/epidemiologia , Chuva , Doença Aguda , Colúmbia Britânica/epidemiologia , Criptosporidiose/parasitologia , Água Potável/parasitologia , Secas , Giardíase/parasitologia , Humanos , Fatores de Risco , TemperaturaRESUMO
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.
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Cryptococcus gattii/classificação , Microbiologia do Ar , Colúmbia Britânica , Criptococose , Cryptococcus gattii/genética , Cryptococcus gattii/crescimento & desenvolvimento , Humanos , Ilhas , Microbiologia do Solo , Árvores/microbiologiaRESUMO
Clostridium difficile is an important cause of enteric infections in humans. Recently, concerns have been raised regarding whether animals could be a source of C. difficile spores. Although colonization has been identified in a number of domestic species, the ability of commensal pests to serve as a reservoir for C. difficile has not been well investigated. The objective of this study was to determine whether urban rats (Rattus spp.) from Vancouver, Canada, carry C. difficile. Clostridium difficile was isolated from the colon contents of trapped rats and was characterized using ribotyping, toxinotyping, and toxin gene identification. Generalized linear mixed models and spatial analysis were used to characterize the ecology of C. difficile in rats. Clostridium difficile was isolated from 95 of 724 (13.1%) rats, although prevalence differed from 0% to 46.7% among city blocks. The odds of being C. difficile positive decreased with increasing weight (odds ratio [OR], 0.67; 95% confidence interval [CI], 0.53 to 0.87), suggesting that carriage is more common in younger animals. The strains isolated included 9 ribotypes that matched recognized international designations, 5 identified by our laboratory in previous studies, and 21 "novel" ribotypes. Some strains were clustered geographically; however, the majority were dispersed throughout the study area, supporting environmental sources of exposure and widespread environmental contamination with a variety of C. difficile strains. Given that urban rats are the source of a number of other pathogens responsible for human morbidity and mortality, the potential for rats to be a source of C. difficile for humans deserves further consideration.
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Portador Sadio/veterinária , Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/veterinária , Animais , Toxinas Bacterianas/genética , Canadá/epidemiologia , Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Clostridioides difficile/classificação , Clostridioides difficile/genética , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Prevalência , Ratos , RibotipagemRESUMO
Introduction: Lyme disease is the most common vector-borne disease in the United States and Canada. The primary vector for the causative agent of Lyme disease, Borrelia burgdorferi, in the Pacific Northwest is the western blacklegged tick, Ixodes pacificus. Materials and Methods: Using active tick surveillance data from British Columbia, Canada, and Washington State, USA, habitat suitability models using MaxEnt (maximum entropy) were developed for I. pacificus to predict its current and mid-century geographic distributions. Passive surveillance data both from BC and WA were also visualized. Results: According to the constructed models, the number of frost-free days during the winter is the most relevant predictor of its habitat suitability, followed by summer climate moisture, ecoregion, and mean minimum fall temperature. The ensemble geographic distribution map predicts that the coastal regions and inland valleys of British Columbia and the Puget Lowlands of Washington State provide the most suitable habitats for I. pacificus. The density map of ticks submitted from passive surveillance data was overlaid on the current distribution map and demonstrates the correlation between numbers of submissions and habitat suitability. Mid-century projections, based on current climate change predictions, indicate a range expansion, especially of low and moderate suitability, from current distribution. Regarding Lyme disease risk, I. pacificus identified from both active and passive surveillance and tested positive for B. burgdorferi were found to be in areas of moderate to very high suitability for I. pacificus. Conclusion: According to developed models, the total suitable habitat area for I. pacificus will expand in the interior regions of British Columbia and Washington State. However, the risk remains small given relatively low infection rates among I. pacificus. Further studies are required to better understand how this might change in the future.
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Background: The COVID-19 pandemic has highlighted health disparities, especially among specific population groups. This study examines the spatial relationship between the proportion of visible minorities (VM), occupation types and COVID-19 infection in the Greater Vancouver region of British Columbia, Canada. Methods: Provincial COVID-19 case data between June 24, 2020, and November 7, 2020, were aggregated by census dissemination area and linked with sociodemographic data from the Canadian 2016 census. Bayesian spatial Poisson regression models were used to examine the association between proportion of visible minorities, occupation types and COVID-19 infection. Models were adjusted for COVID-19 testing rates and other sociodemographic factors. Relative risk (RR) and 95% Credible Intervals (95% CrI) were calculated. Results: We found an inverse relationship between the proportion of the Chinese population and risk of COVID-19 infection (RR = 0.98 95% CrI = 0.96, 0.99), whereas an increased risk was observed for the proportions of the South Asian group (RR = 1.10, 95% CrI = 1.08, 1.12), and Other Visible Minority group (RR = 1.06, 95% CrI = 1.04, 1.08). Similarly, a higher proportion of frontline workers (RR = 1.05, 95% CrI = 1.04, 1.07) was associated with higher infection risk compared to non-frontline. Conclusion: Despite adjustments for testing, housing, occupation, and other social economic status variables, there is still a substantial association between the proportion of visible minorities, occupation types, and the risk of acquiring COVID-19 infection in British Columbia. This ecological analysis highlights the existing disparities in the burden of diseases among different visible minority populations and occupation types.
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COVID-19 , Grupos Minoritários , Humanos , Colúmbia Britânica/epidemiologia , COVID-19/epidemiologia , Teste para COVID-19 , Pandemias , Teorema de Bayes , OcupaçõesRESUMO
It has been over a decade since Cryptococcus gattii was first recognized as the causative organism of an outbreak of cryptococcosis on Vancouver Island, British Columbia. A number of novel observations have been associated with the study of this emergent pathogen. A novel genotype of C. gattii, VGIIa was described as the major genotype associated with clinical disease. Minor genotypes, VGIIb and VGI, are also responsible for disease in British Columbians, in both human and animal populations. The clinical major genotype VGIIa and minor genotype VGIIb are identical to C. gattii isolated from the environment of Vancouver Island. There is more heterogeneity in VGI, and a clear association with the environment is not apparent. Between 1999 and 2010, there have been 281 cases of C. gattii cryptococcosis. Risk factors for infection are reported to be age greater than 50 years, history of smoking, corticosteroid use, HIV infection, and history of cancer or chronic lung disease. The major C. gattii genotype VGIIa is as virulent in mice as the model Cryptococcus, H99 C. neoformans, although the outbreak strain produces a less protective inflammatory response in C57BL/6 mice. The minor genotype VGIIb is significantly less virulent in mouse models. Cryptococcus gattii is found associated with native trees and soil on Vancouver Island. Transiently positive isolations have been made from air and water. An ecological niche for this organism is associated within a limited biogeoclimatic zone characterized by daily average winter temperatures above freezing.
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Criptococose/epidemiologia , Criptococose/microbiologia , Cryptococcus gattii/isolamento & purificação , Surtos de Doenças , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Colúmbia Britânica/epidemiologia , Criança , Pré-Escolar , Criptococose/imunologia , Cryptococcus gattii/classificação , Cryptococcus gattii/genética , Modelos Animais de Doenças , Feminino , Genótipo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Epidemiologia Molecular , Fatores de Risco , Adulto JovemRESUMO
Lyme disease, caused by Borrelia burgdorferi sensu lato (s.l.) complex, is the most common vector-borne disease in North America. This disease has a much lower incidence in western compared with eastern North America. Passive tick surveillance data submitted over 17 years from 2002 to 2018 were analyzed to determine the occurrence of tick species and the prevalence of Borrelia spp. in ticks in British Columbia (BC), Canada. The BC Centre for Disease Control Public Health Laboratory received tick submissions from physicians, veterinarians, and BC residents. Ticks were identified to species, and all ticks, except Dermacentor andersoni, were tested using generic B. burgdorferi s.l. primer sets and species-specific PCR primer sets for B. burgdorferi sensu stricto (s.s.). Tick submission data were analyzed to assess temporal and geographical trends, tick life stages, and tick species. Poisson regression was used to assess temporal trends in annual tick submissions. A total of 15,464 ticks were submitted. Among these, 0.29% (n = 10,235) of Ixodes spp. ticks and 5.3% (n = 434) of Rhipicephalus sanguineus ticks were found carrying B. burgdorferi s.s. B. burgdorferi s.s. was primarily detected in Ixodes pacificus (52%; n = 16) and Ixodes angustus ticks (19%; n = 6) retrieved from humans (n = 5) and animals (n = 26). B. burgdorferi was found in ticks submitted throughout the year. Ixodes spp. ticks were primarily submitted from the coastal regions of southwestern BC, and D. andersoni ticks were primarily submitted from southern interior BC. The number of human tick submissions increased significantly (p < 0.001) between 2013 and 2018. The annual prevalence of B. burgdorferi in ticks remained stable during the study period. These findings correspond to those observed in US Pacific Northwestern states. Passive tick surveillance is an efficient tool to monitor long-term trends in tick distribution and B. burgdorferi prevalence in a low endemicity region.
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Borrelia burgdorferi , Borrelia , Ixodes , Doença de Lyme , Animais , Borrelia/genética , Borrelia burgdorferi/genética , Colúmbia Britânica/epidemiologia , Doença de Lyme/epidemiologia , Doença de Lyme/veterináriaRESUMO
In 2009, an expansion of West Nile virus (WNV) into the Canadian province of British Columbia was detected. Two locally acquired cases of infection in humans and 3 cases of infection in horses were detected by ELISA and plaque-reduction neutralization tests. Ten positive mosquito pools were detected by reverse transcription PCR. Most WNV activity in British Columbia in 2009 occurred in the hot and dry southern Okanagan Valley. Virus establishment and amplification in this region was likely facilitated by above average nightly temperatures and a rapid accumulation of degree-days in late summer. Estimated exposure dates for humans and initial detection of WNV-positive mosquitoes occurred concurrently with a late summer increase in Culex tarsalis mosquitoes (which spread western equine encephalitis) in the southern Okanagan Valley. The conditions present during this range expansion suggest that temperature and Cx. tarsalis mosquito abundance may be limiting factors for WNV transmission in this portion of the Pacific Northwest.
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Culex/virologia , Insetos Vetores/virologia , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Colúmbia Britânica/epidemiologia , Clima , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/virologia , Cavalos , Humanos , RNA Viral/química , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental/genéticaRESUMO
The purpose of this study was to describe the geographic distribution and model the ecological niche for Borrelia burgdorferi (Johnson, Schmidt, Hyde, Steigerwaldt & Brenner), Ixodes pacificus (Cooley & Kohls), and Ixodes angustus (Neumann), the bacterium and primary tick vectors for Lyme disease, in British Columbia (BC), Canada. We employed a landscape epidemiology approach using geographic information systems mapping and ecological niche modeling (Genetic Algorithm for Rule-set Prediction) to identify geographical areas of disease transmission risk. Forecasted optimal ecological niche areas for B. burgdorferi are focused along the coast of Vancouver Island, the southwestern coast of the BC mainland, and in valley systems of interior BC roughly along and below the N51 degree line of latitude. These findings have been used to increase public and physician awareness of Lyme disease risk, and prioritize future field sampling for ticks in BC.
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Ixodes/microbiologia , Doença de Lyme/epidemiologia , Ração Animal , Animais , Borrelia/imunologia , Borrelia burgdorferi/imunologia , Colúmbia Britânica/epidemiologia , Ecossistema , Geografia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Ixodes/crescimento & desenvolvimento , Larva/fisiologia , Doença de Lyme/imunologiaRESUMO
BACKGROUND: Food- and water-borne pathogens exhibit spatial heterogeneity, but attribution to specific environmental processes is lacking while anthropogenic climate change alters these processes. The goal of this study was to investigate ecology, land-use and health associations of these pathogens and to make future disease projections. METHODS: The rates of five acute gastrointestinal illnesses (AGIs) (campylobacteriosis, Verotoxin- producing Escherichia coli, salmonellosis, giardiasis and cryptosporidiosis) from 2000 to 2013 in British Columbia, Canada, were calculated across three environmental variables: ecological zone, land use, and aquifer type. A correlation analysis investigated relationships between 19 climatic factors and AGI. Mean annual temperature at the ecological zone scale was used in a univariate regression model to calculate annual relative AGI risk per 1 °C increase. Future cases attributable to climate change were estimated into the 2080s. FINDINGS: Each of the bacterial AGI rates was correlated with several annual temperature-related factors while the protozoan AGIs were not. In the regression model, combined relative risk for the three bacterial AGIs was 1.1 [95% CI: 1.02-1.21] for every 1 °C in mean annual temperature. Campylobacteriosis, salmonellosis and giardiasis rates were significantly higher (p < 0.05) in the urban land use class than in the rural one. In rural areas, bacteria and protozoan AGIs had significantly higher rates in the unconsolidated aquifers. Verotoxin-producing Escherichia coli rates were significantly higher in watersheds with more agricultural land, while rates of campylobacteriosis, salmonellosis and giardiasis were significantly lower in agricultural watersheds. Ecological zones with higher bacterial AGI rates were generally projected to expand in range by the 2080s. INTERPRETATION: These findings suggest that risk of AGI can vary across ecosystem, land use and aquifer type, and that warming temperatures may be associated with an increased risk of food-borne AGI. In addition, spatial patterns of these diseases are projected to shift under climate change.
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Água Subterrânea , Doenças Transmitidas pela Água , Animais , Colúmbia Britânica , Mudança Climática , EcossistemaRESUMO
We investigated whether risk of sporadic enteric disease differs by drinking water source and type using surveillance data and a geographic information system. We performed a cross-sectional analysis, at the individual level, that compared reported cases of enteric disease with drinking water source (surface or ground water) and type (municipal or private). We mapped 814 cases of campylobacteriosis, cryptosporidiosis, giardiasis, salmonellosis and verotoxigenic Escherichia coli infection, in a region of British Columbia, Canada, from 1996 to 2005, and determined the water source and type for each case's residence. Over the 10-year period, the risk of disease was 5.2 times higher for individuals living on land parcels serviced by private wells and 2.3 times higher for individuals living on land parcels serviced by the municipal surface/ground water mixed system, than the municipal ground water system. Rates of sporadic enteric disease potentially differ by drinking water source and type. Geographic information system technology and surveillance data are accessible to local public health authorities and used together are an efficient and affordable way to assess the role of drinking water in sporadic enteric disease.
Assuntos
Infecções por Campylobacter/epidemiologia , Criptosporidiose/epidemiologia , Infecções por Enterobacteriaceae/epidemiologia , Giardíase/epidemiologia , Microbiologia da Água , Abastecimento de Água , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Colúmbia Britânica/epidemiologia , Campylobacter/isolamento & purificação , Infecções por Campylobacter/transmissão , Criança , Pré-Escolar , Estudos Transversais , Criptosporidiose/transmissão , Cryptosporidium/isolamento & purificação , Infecções por Enterobacteriaceae/transmissão , Escherichia coli/isolamento & purificação , Feminino , Sistemas de Informação Geográfica , Giardia/isolamento & purificação , Giardíase/transmissão , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Salmonella/isolamento & purificação , Adulto JovemRESUMO
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 chi2 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.