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Background: We identified the need to modernize frostbite management in our northern centre and implemented a treatment protocol in 2015. Our aim was to describe the clinical course of patients presenting to the hospital since the implementation of the protocol., Methods: This was a retrospective case series from Whitehorse General Hospital, Whitehorse, Yukon Territory, Canada. We reviewed the charts of patients who presented to the hospital with grade 2-4 frostbite and were treated as per our protocol between Feb. 9, 2015, and Feb. 8, 2020. Patients with grade 2-4 frostbite received iloprost; in addition, those with grade 4 frostbite received alteplase and heparin. We determined the number of digits affected and salvaged, and the time from presentation to the emergency department to treatment initiation. We also examined patients' demographic characteristics, predisposing events, frostbite severity and adverse drug reactions., Results: In 22 patients treated for grade 2-4 frostbite, 142 digits were affected: 59 with grade 2 frostbite, 25 with grade 3 frostbite and 58 with grade 4 frostbite; of the 142, 113 (79.6%) were salvaged. All 29 digits amputated had grade 4 frostbite. The mean time from presentation to iloprost initiation was reduced from 32.9 hours in 2015 to 3.0 hours in 2020. Sports (10 cases [45%]) and alcohol use (6 [27%]) were the most common precipitating events, with alcohol use tending to result in more severe injury (grade 4 in 5 of 6 cases). Adverse reactions with iloprost (e.g., headache) were common but mild. Adverse reactions with alteplase (e.g., bleeding) were less common but of greater clinical significance., Interpretation: Over the study period, our protocol contributed to improvement in frostbite care at our institution, resulting in a digit salvage rate comparable to other published results. Our 5-year experience shows that advanced medical care of frostbite can be achieved, even at a rural centre., Competing Interests: Competing interests: Josianne Gauthier is employed by the Whitehorse General Hospital (Yukon Hospital Corporation). No other competing interests were declared., (© 2021 CMA Joule Inc. or its licensors.)

Trichinella spp. nematodes are commonly found in bear species (Ursidae) and can pose severe health risks to humans when infective first-stage larvae are ingested in meat. Samples of tongue or masseter muscle from 22 male and 11 female American black bears (Ursus americanus; mean age 6.5 yr, range 1-16 yr) and 22 male, eight female, and one unknown sex grizzly bears (Ursus arctos; mean age 8.8 yr, range 2-28 yr), from Yukon, Canada, were tested to determine prevalence and intensity of Trichinella spp. infection. For black bears, prevalence was 20% and mean intensity was 401 larvae per gram of tissue (LPG), whereas for grizzly bears, prevalence was 71%, and mean infection intensity was 35 LPG. Isolates from all positive samples were identified as genotype Trichinella-T6 by multiplex PCR. For black bears, prevalence is the highest reported in Canada and infection intensity the highest recorded in North America. One black bear had a larval burden of 1,173 LPG, the second highest recorded in any host species. The prevalence in grizzly bears was the highest reported in Canada for this host. In total, 90% (27 of 30) of infected bears had infection burdens above the human food safety threshold of ≥1 LPG, reinforcing the importance of communicating the health risks to people consuming bear meat., (© Wildlife Disease Association 2021.)

Background: Species of Trichinella are globally important foodborne parasites infecting a number of domestic and wild vertebrates, including humans. Free-ranging carnivores can act as sentinel species for detection of Trichinella spp. Knowledge of the epidemiology of these parasites may help prevent Trichinella spp. infections in northern Canadian animals and people. Previous research on Trichinella spp. in wildlife from Yukon did not identify risk factors associated with infection, or the diversity and identity of species of Trichinella in regional circulation, based on geographically extensive sampling with large sample sizes., Methods: In a cross-sectional study, we determined the prevalence, infection intensity, risk factors, and species or genotypes of Trichinella in wolverine (Gulo gulo) in two regions of Yukon, Canada, from 2013-2017. A double separatory funnel digestion method followed by mutiplex PCR and PCR-RFLP were used to recover and identify species of Trichinella, respectively., Results: We found larvae of Trichinella in the tongues of 78% (95% CI 73-82) of 338 wolverine sampled. The odds of adult (≥ 2 years) and yearling (1 year) wolverine being Trichinella spp.-positive were four and two times higher, respectively, compared to juveniles (<1 year). The odds of Trichinella spp. presence were three times higher in wolverine from southeast than northwest Yukon. The mean intensity of infection was 22.6 ± 39 (SD, range 0.1-295) larvae per gram. Trichinella T6 was the predominant genotype (76%), followed by T. nativa (8%); mixed infections with Trichinella T6 and T. nativa (12%) were observed. In addition, T. spiralis was detected in one wolverine. Out of 22 isolates initially identified as T. nativa in multiplex PCR, 14 were analyzed by PCR-RFLP to distinguish them from T. chanchalensis, a recently discovered cryptic species, which cannot be distinguished from the T. nativa on multiplex PCR. Ten isolates were identified either as T. chanchalensis alone (n = 7), or mixed infection with T. chanchalensis and T. nativa (n = 2) or T. chanchalensis and Trichinella T6 (n = 1)]., Conclusions: Wolverine hosted high prevalence, high larval intensity, and multiple species of Trichinella, likely due to their scavenging habits, apex position in the food chain, and wide home range. Wolverine (especially adult males) should be considered as a sentinel species for surveys for Trichinella spp. across their distributional range.

Introduction and Aims: This paper examines the impact of an alcohol labelling intervention on recall of and support for standard drink (SD) labels, estimating the number of SDs in alcohol containers, and intended and unintended use of SD labels., Design and Methods: A quasi-experimental study was conducted in Canada where labels with a cancer warning, national drinking guidelines and SD information were applied to alcohol containers in the single liquor store in the intervention site, while usual labelling continued in the two liquor stores in the comparison site. Three waves of surveys were conducted in both sites before and at two time-points after the intervention with 2049 cohort participants. Generalised estimating equations were applied to estimate changes in all outcomes., Results: Participants in the intervention relative to the comparison site had greater odds of recalling [adjusted odds ratio (AOR) 5.69, 95% confidence interval (CI) 3.02, 10.71] and supporting SD labels (AOR 1.49, 95% CI 1.04, 2.12) and lower odds of reporting using SD labels to purchase high strength, low-cost alcohol (AOR 0.65, 95% CI 0.45, 0.93). Exposure to the labels had negligible effects on accurately estimating the number of SDs (AOR 1.06, 95% CI 0.59, 1.93) and using SD labels to drink within guidelines (AOR 1.04, 95% CI 0.75, 1.46)., Discussion and Conclusions: Evidence-informed labels increased support for and decreased unintended use of SD labels. Such labels can improve accuracy in estimating the number of SDs in alcohol containers and adherence to drinking guidelines., (© 2020 Her Majesty the Queen in Right of Canada. Drug and Alcohol Review © 2020 Australasian Professional Society on Alcohol and other Drugs.)

Objective: Evidence-informed alcohol warning labels (AWLs) are a promising, well-targeted strategy to increase consumer awareness of health risks. We assessed consumers' baseline knowledge of alcohol-related cancer risk, standard drinks, and low-risk drinking guidelines as well as levels of support for AWLs. We further assessed associations with sociodemographic factors., Method: Forming part of a larger study testing new evidence-informed AWLs in a northern Canadian territory compared with a neighboring territory, baseline surveys were completed among liquor store patrons systematically selected in both sites. Chi-square and multivariable logistic regression analyses were performed to assess outcomes., Results: In total, 836 liquor store patrons (47.8% female) completed baseline surveys across both sites. Overall, there was low knowledge of alcohol-related cancer risk (24.5%), limited ability to calculate a standard drink (29.5%), and low knowledge of daily (49.5%) and weekly (48.2%) low-risk drinking guideline limits. There was moderate support for AWLs with a health warning (55.9%) and standard drink information (51.4%), and lower support for low-risk drinking guideline labels (38.7%). No sociodemographic characteristics were associated with cancer knowledge. Identifying as female and having adequate health literacy were associated with support for all three AWLs; high alcohol use was associated with not supporting standard drink (adjusted odds ratio = 0.60, 95% CI [0.40, 0.88]) and low-risk drinking guideline (adjusted odds ratio = 0.57, 95% CI [0.38, 0.87]) labels., Conclusions: Few consumers in this study had key alcohol-related health knowledge; however, there was moderate support for AWLs as a tool to raise awareness. Implementation of information-based interventions such as evidence-informed AWLs with health messages including alcohol-related cancer risk, standard drink information, and national drinking guidelines is warranted.

Objective: There is limited evidence that alcohol warning labels (AWLs) affect population alcohol consumption. New evidence-informed AWLs were introduced in the sole government-run liquor store in Whitehorse, Yukon, that included a cancer warning (Ca), low-risk drinking guidelines (LRDGs) and standard drink (SD) messages. These temporarily replaced previous pregnancy warning labels. We test if the intervention was associated with reduced alcohol consumption., Method: An interrupted time series study was designed to evaluate the effects of the AWLs on consumption for 28 months before and 14 months after starting the intervention. Neighboring regions of Yukon and Northwest Territories served as control sites. About 300,000 labels were applied to 98% of alcohol containers sold in Whitehorse during the intervention. Multilevel regression analyses of per capita alcohol sales data for people age 15 years and older were performed to examine consumption levels in the intervention and control sites before, during, and after the AWLs were introduced. Models were adjusted for demographic and economic characteristics over time and region., Results: Total per capita retail alcohol sales in Whitehorse decreased by 6.31% (t test p < .001) during the intervention. Per capita sales of labeled products decreased by 6.59% (t test p < .001), whereas sales of unlabeled products increased by 6.91% (t test p < .05). There was a still larger reduction occurring after the intervention when pregnancy warning labels were reintroduced (-9.97% and -10.29%, t test p < .001)., Conclusions: Applying new AWLs was associated with reduced population alcohol consumption. The results are consistent with an accumulating impact of the addition of varying and highly visible labels with impactful messages., Competing Interests: Tim Stockwell received research funds and travel expenses from both the Swedish and Finnish government alcohol monopolies in the past 4 years. Other authors declare no conflicts of interest.

Objective: Although the World Health Organization (WHO) declared alcohol a Class 1 carcinogen 30 years ago, few governments have communicated this fact to the public. We illustrate how alcohol industry groups seek to keep their customers in the dark about alcohol-related cancer risks. In Canada, a federally funded scientific study examining the introduction of cancer warning labels on containers was shut down following industry interference. We show that the industry complaints about the study had no legal merit. Of 47 WHO member countries with alcohol warning labels, only South Korea requires cancer warnings on alcohol containers. However, industry complaints, supported by sympathetic governments, helped weaken the warning labels' implementation. Ireland has legislated for cancer warnings but faces continuing legal opposition expressed through regional and global bodies. Cancer societies and the public health community have failed to counter industry pressures to minimize consumer awareness of alcohol's cancer risks. Placing cancer warnings on alcohol containers could make a pivotal difference in motivating both drinkers to consume less and regulators to introduce more effective policies to reduce the serious harms of alcohol consumption.

Objective: Alcohol labels are one strategy for communicating health information to consumers. This study tested the extent to which consumers recalled alcohol labels with national drinking guidelines and examined the impact of labels on awareness and knowledge of the guidelines., Method: A quasi-experimental study was conducted in two jurisdictions in northern Canada examining the impact of labels on the following outcomes: unprompted and prompted recall of the drinking guideline label message, awareness of the drinking guidelines, and knowledge of the daily and weekly recommended drink limits. The intervention site applied labels with national drinking guidelines, a cancer warning, and standard drink information to alcohol containers in its liquor store, whereas the comparison site did not apply these labels. In total, 2,049 cohort participants in both sites were recruited to complete surveys before and at two time points after the intervention. Changes in outcomes were examined using generalized estimating equations., Results: After the intervention, unprompted and prompted recall of the drinking guideline label message increased more in the intervention versus comparison site (adjusted odds ratio [AOR] = 10.8, 95% CI [0.9, 127.6]; AOR = 7.0, 95% CI [3.3, 14.9], respectively). Awareness of the drinking guidelines increased 2.9 times more in the intervention versus comparison site (AOR = 2.9, 95% CI [2.0, 4.3]). In addition, knowledge of the daily and weekly drink limits increased 1.5 and 1.4 times more in the intervention versus comparison site, respectively (daily: AOR = 1.5, 95% CI [1.0, 2.1]; weekly: AOR = 1.4, 95% CI [1.0, 2.0])., Conclusions: Enhanced alcohol labels get noticed and may be an effective population-level strategy for increasing awareness and knowledge of national drinking guidelines.

Objective: This study tested the initial and continued effects of cancer warning labels on drinkers' recall and knowledge that alcohol can cause cancer., Method: A quasi-experiment was conducted to examine changes in the intervention versus comparison site for three outcomes: unprompted and prompted recall of the cancer warning, and knowledge that alcohol can cause cancer. The intervention site applied cancer warning labels to alcohol containers in its liquor store for 1 month, and the two liquor stores in the comparison site did not apply cancer labels. In total, 2,049 unique cohort participants (1,056 male) were recruited at liquor stores in the intervention and comparison sites to participate in surveys 4 months before labels were applied and 2 and 6 months after the cancer label was halted because of alcohol industry interference. Generalized estimating equations tested differences in outcomes between sites over time adjusting for socio-demographics and other covariates., Results: Two months after the cancer label, unprompted (+24.2% vs. +0.6%; adjusted odds ratio [AOR] = 32.7, 95% CI [5.4, 197.7]) and prompted (+35.7% vs. +4.1%; AOR = 6.2, 95% CI [3.6, 10.9]) recall increased to a greater extent in the intervention versus comparison site. There was a 10% greater increase in knowledge (+12.1% vs. +11.6%; AOR = 1.1, 95% CI [0.7, 1.5]) 2 months after the cancer label in the intervention versus comparison site. Similar results were found 6 months after the cancer label for all three outcomes., Conclusions: In a real-world setting, cancer warning labels get noticed and increase knowledge that alcohol can cause cancer. Additional cancer label intervention studies are required that are not compromised by industry interference.

Yukon Territory (YT) is a remote region in northern Canada with ongoing spread of tuberculosis (TB). To explore the utility of whole genome sequencing (WGS) for TB surveillance and monitoring in a setting with detailed contact tracing and interview data, we used a mixed-methods approach. Our analysis included all culture-confirmed cases in YT (2005-2014) and incorporated data from 24-locus Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats (MIRU-VNTR) genotyping, WGS and contact tracing. We compared field-based (contact investigation (CI) data + MIRU-VNTR) and genomic-based (WGS + MIRU-VNTR + basic case data) investigations to identify the most likely source of each person's TB and assessed the knowledge, attitudes and practices of programme personnel around genotyping and genomics using online, multiple-choice surveys (n = 4) and an in-person group interview (n = 5). Field- and genomics-based approaches agreed for 26 of 32 (81%) cases on likely location of TB acquisition. There was less agreement in the identification of specific source cases (13/22 or 59% of cases). Single-locus MIRU-VNTR variants and limited genetic diversity complicated the analysis. Qualitative data indicated that participants viewed genomic epidemiology as a useful tool to streamline investigations, particularly in differentiating latent TB reactivation from the recent transmission. Based on this, genomic data could be used to enhance CIs, focus resources, target interventions and aid in TB programme evaluation.

A central goal for reintroduced populations of threatened wood bison ( Bison bison athabascae) is to maintain them free of diseases of concern, particularly bovine tuberculosis (caused by Mycobacterium bovis) and brucellosis (caused by Brucella abortus). A wood bison population in southwestern Yukon, Canada was reintroduced into the wild in 1988, but no health assessment has been done since then. To provide an initial assessment of the health status and, hence, the conservation value of this population, we serologically tested 31 wood bison (approximately 3% of the population) for pathogens of interest and obtained histopathology results for select tissues. We found no evidence of exposure to M. bovis or Brucella spp., but antibodies were present to bovine parainfluenza virus 3, bovine coronavirus, Leptospira interrogans, and Neospora caninum, with seroprevalences of 87, 7, 61, and 7% of the tested animals, respectively. Reintroduced wood bison in southwestern Yukon may be of high value for wood bison recovery because it is a large and geographically isolated population with no bacteriologic, histopathologic, or serologic evidence of exposure to Brucella spp. or M. bovis.

Background: Selenium (Se) has been reported to protect against the neurotoxicity of mercury (Hg). However, the effect of Se against Hg on cardiovascular diseases remains unclear. Inuit living in the Arctic have high exposure to both Se and Hg through their marine mammal and fish rich traditional diet., Objective: To characterize the co-exposure of Hg and Se among Inuit in Canada and to assess the associations between Hg, Se and cardiovascular health outcomes, including stroke, hypertension, and myocardial infarction (MI)., Methods: Data was collected from the International Polar Year Inuit Health Survey (IHS) conducted in 2007 and 2008. Blood Se and Hg were measured, and self-report cardiovascular health outcomes were collected through a questionnaire interview from 2169 adults aged 18 and above., Results: The mean age was 42.4years, and 38.7% of the participants were male. The geometric means (GM) of blood Se and total Hg were 319.5μg/L and 7.0μg/L, respectively. The crude prevalence of heart attack, stroke and hypertension were 3.55%, 2.36%, and 24.47% respectively. Participants were categorized into 4 exposure groups according to blood Hg (high: ≥7.8μg/L; low: <7.8μg/L), and Se (high: ≥280μg/L; low: <280μg/L). The odds ratio (OR) of cardiovascular outcomes were estimated using general linearized models. Results showed the low Se and high Hg group had a higher prevalence of cardiovascular disease (OR=1.76 for hypertension, 1.57 for stroke, and 1.26 for MI. However, the prevalence was decreased in both the high Se and low Hg group (OR=0.57 for hypertension, 0.44 for stroke, and 0.27 for MI) and the high Se and high Hg group (OR=1.14 for hypertension, 0.31 for stroke, and 0.80 for MI)., Conclusions: The high Se and low Hg group had the lowest prevalence of cardiovascular outcomes, except for stroke. These results provide evidence that Se may exhibit a protective effect against Hg on cardiovascular disease., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Although cancer is the leading cause of death in Canada, cancer in the North has been incompletely described., Objective: To determine cancer mortality rates in the Yukon Territory, compare them with Canadian rates, and identify major causes of cancer mortality., Design: The Yukon Vital Statistics Registry provided all cancer deaths for Yukon residents between 1999-2013. Age-standardised mortality rates (ASMRs) were calculated using direct standardisation and compared with Canadian rates. Standardised mortality ratios (SMRs) were calculated using indirect standardisation relative to age-specific rates from Canada, British Columbia (BC), and three sub-provincial BC administrative health regions : Interior Health (IH), Northern Health (NH) and Vancouver Coastal Health (VCH). Trends in smoothed ASMRs were examined with graphical methods., Results: Yukon's all-cancer ASMRs were elevated compared with national and provincial rates for the entire period. Disparities were greatest compared with the urban VCH: prostate (SMR VCH =246.3, 95% CI 140.9-351.6), female lung (SMR VCH =221.2, 95% CI 154.3-288.1), female breast (SMR VCH =169.0 95% CI, 101.4-236.7), and total colorectal (SMR VCH =149.3, 95% CI 101.8-196.8) cancers were significantly elevated. Total stomach cancer mortality was significantly elevated compared with all comparators., Conclusions: Yukon cancer mortality rates were elevated compared with national, provincial, urban, and southern-rural jurisdictions. More research is required to elucidate these differences.

Winter ticks (Dermacentor albipictus) on elk (Cervus elaphus canadensis) have recently increased in numbers in the Yukon, Canada, potentially posing risks to other indigenous host species in the region. To evaluate the regional source of winter ticks in the Yukon, we sequenced one nuclear (ITS-2) and two mitochondrial (16SrRNA and COI) genes, and genotyped 14 microsatellite loci from 483 winter tick specimens collected across North America. We analyzed genetic variation across the geographic and host ranges of this tick species with the use of variance partitioning, Bayesian clustering, and standard population genetic analyses. Based on our results, winter ticks on elk in the Yukon could have originated either by translocation from central Alberta or by northward range expansion of more geographically proximate populations in northern Alberta and British Columbia. Although there was some genetic structuring of winter ticks on different hosts in the same region, we found little evidence of host specificity in winter ticks from five ungulate host species, suggesting that the winter ticks on elk in the Yukon could potentially become established on other locally available host species such as moose (Alces alces).

Background: Yukon, a territory in northern Canada, has one of the highest reported sexually transmitted chlamydia infection rates in the country., Objective: We examined screening practices among physicians and community nurses to elucidate factors that may be contributing to the high rates., Design: Cross-sectional survey., Methods: A questionnaire was distributed to all physicians in Yukon and all community nurses in Yukon's communities. We surveyed sexual health assessment frequency, chlamydia testing frequency and barriers to screening. Comparison of physician testing practices was performed to another Canadian jurisdiction, which previously undertook a similar survey. Survey results were compared to the available laboratory data in Yukon., Results: Eligible physicians and nurses, 79% and 77%, respectively, participated in the survey. Physicians tested 15 to 24-year-old females more frequently than 15 to 24-year-old males for chlamydia (p = 0.007). Physicians who asked sexual health assessment questions were more likely to test for chlamydia in both females (p < 0.001) and males (p = 0.032). More physicians screened females based on risk factors compared to males. General practice physicians in Yukon were more likely to test females for chlamydia than general practice physicians in Toronto, Canada (p < 0.001). Community nurses had different testing patterns than physicians, with a lower overall frequency of testing, equal frequency of testing males and females, and in applying risk factor-based screening to both males and females. Barriers to screening included testing causing patient discomfort, patients reluctant to discuss screening, health provider uncomfortable conducting sexually transmitted infection tests and sexual health assessments, among others. Laboratory data in Yukon appear to confirm provider screening patterns., Conclusions: This survey provides valuable information on health provider screening patterns. We have some evidence which suggests that chlamydia testing rates may be higher among patients seen by physicians in Yukon in comparison to another Canadian jurisdiction. However, more consistent application of optimal screening methods with support to "start the conversation" around sexual health may assist in overcoming barriers to screening and in addressing Yukon's high rate of chlamydia.

Objective: Certain types of the human papillomavirus (HPV) are highly associated with cervical cancer or dysplasia, but its prevalence is largely unknown in northern Canada where there is significant aboriginal representation and unique barriers to accessing care. This study determined the prevalence of HPV infection and its association with cervical cancer precursor lesions in Yukon, Canada., Materials and Methods: This was a cross-sectional study of 1,542 women attending routine Pap smear screening in 14 communities in Yukon, from February 2009 to June 2010. Type-specific HPV infection was detected by an in-house Luminex assay. Cervical Pap cytology was evaluated by pathologists blinded to HPV test results., Results: The overall HPV prevalence rate in Yukon women was higher than those reported in some Canadian provinces and other countries. Human papillomavirus infection prevalence rates were 24.5% for any type, 18.4% for high-risk types, 6.2% for HPV types 16 or 18, 6.7% for HPV α-7 species, and 10.6% for HPV α-9 species. Human papillomavirus infection was strongly associated with single marital status or having 2 or more sexual partners in the past year. Human papillomavirus infection (overall, high-risk types, HPV-16/18, α-7, or α-9 species) was strongly associated with Pap cytological abnormalities (adjusted odds ratios ranged from 8.4 to 44.2)., Conclusions: As in other areas of northern Canada, HPV prevalence for high-risk types and α-7 species is high among women in the Yukon. Sexual behavioral factors strongly influence HPV prevalence rates. The findings may have implications for HPV vaccination and health promotion programs in northern regions.

A consistent methodology for assessing the accumulating effects of natural and manmade change on riverine systems has not been developed for a whole host of reasons including a lack of data, disagreement over core elements to consider, and complexity. Accumulated state assessments of aquatic systems is an integral component of watershed cumulative effects assessment. The Yukon River is the largest free flowing river in the world and is the fourth largest drainage basin in North America, draining 855,000 km(2) in Canada and the United States. Because of its remote location, it is considered pristine but little is known about its cumulative state. This review identified 7 "hot spot" areas in the Yukon River Basin including Lake Laberge, Yukon River at Dawson City, the Charley and Yukon River confluence, Porcupine and Yukon River confluence, Yukon River at the Dalton Highway Bridge, Tolovana River near Tolovana, and Tanana River at Fairbanks. Climate change, natural stressors, and anthropogenic stresses have resulted in accumulating changes including measurable levels of contaminants in surface waters and fish tissues, fish and human disease, changes in surface hydrology, as well as shifts in biogeochemical loads. This article is the first integrated accumulated state assessment for the Yukon River basin based on a literature review. It is the first part of a 2-part series. The second article (Dubé et al. 2013a, this issue) is a quantitative accumulated state assessment of the Yukon River Basin where hot spots and hot moments are assessed outside of a "normal" range of variability., (Copyright © 2012 SETAC.)

Carnitine palmitoyltransferase 1A (CPT1A), encoded by the gene CPT1A, is the hepatic isoform of CPT1 and is a major regulatory point in long-chain fatty acid oxidation. CPT1A deficiency confers risk for hypoketotic hypoglycaemia, hepatic encephalopathy, seizures, and sudden unexpected death in infancy (SUDI). It remains controversial whether the CPT1A gene variant, c.1436C>T (p.P479L), identified in Inuit, First Nations, and Alaska Native infants, causes susceptibility to decompensation, in particular during times of fever and intercurrent illness. Although newborn screening for the P479L variant occurs in some jurisdictions, background knowledge about the presence of the variant in Canadian Aboriginal populations is lacking. In an effort to understand the population implications of the variant in northern Canada, overall frequencies of the variant were assessed. Further studies are underway to determine associated risk. Ethics approval was obtained from university REBs, local research institutes, and with consultation with territorial Aboriginal groups. Newborn screening blood spots from all infants born in 2006 in the three territories were genotyped for the p.P479L variant. p.P479L (c.1436C>T) allele frequencies in the three territories were 0.02, 0.08, and 0.77 in Yukon (n=325), Northwest Territories (n=564), and Nunavut (n=695), respectively. Homozygosity rates were 0%, 3%, and 64%. Aboriginal status was available only in NWT, with allele frequencies of 0.04, 0.44, 0.00, and 0.01 for First Nations, Inuvialuit/Inuit, Métis, and non-Aboriginal populations. Although individual blood spots were not identified for Aboriginal ethnicity in Nunavut infants, ~90% of infants in Nunavut are born to Inuit women. The allele frequency and rate of homozygosity for the CPT1A P479L variant were high in Inuit and Inuvialuit who reside in northern coastal regions. The variant is present at a low frequency in First Nations populations, who reside in areas less coastal than the Inuit or Inuvialuit in the two western territories. The significance of the population and geographic distribution remains unclear, but the high population frequencies of the variant suggest a historically low penetrance for adverse outcomes. Further evidence is needed to determine if there is an increased risk for infant mortality and morbidity and whether newborn screening will be indicated on a population basis., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Background: Few studies have investigated the prevalence and risk factors of asthma in Canadian Aboriginal children., Objective: To determine the prevalence of asthma and asthma-like symptoms, as well as the risk factors for asthma-like symptoms, in Aboriginal and non-Aboriginal children living in the northern territories of Canada., Methods: Data on 2404 children, aged between 0 and 11 years, who participated in the North component of the National Longitudinal Survey of Children and Youth were used in the present study. A child was considered to have an asthma-like symptom if there was a report of ever having had asthma, asthma attacks or wheeze in the past 12 months., Results: After excluding 59 children with missing information about race, 1399 children (59.7%) were of Aboriginal ancestry. The prevalence of asthma was significantly lower (P<0.05) in Aboriginal children (5.7%) than non-Aboriginal children (10.0%), while the prevalence of wheeze was similar between Aboriginal (15.0%) and non-Aboriginal (14.5%) children. In Aboriginal children, infants and toddlers had a significantly greater prevalence of asthma-like symptoms (30.0%) than preschool-aged children (21.5%) and school-aged children (11.5%). Childhood allergy and a mother's daily smoking habit were significant risk factors for asthma-like symptoms in both Aboriginal and non-Aboriginal children. In addition, infants and toddlers were at increased risk of asthma-like symptoms in Aboriginal children. In analyses restricted to specific outcomes, a mother's daily smoking habit was a significant risk factor for current wheeze in Aboriginal children and for ever having had asthma in non-Aboriginal children., Conclusions: Asthma prevalence appears to be lower in Aboriginal children than in non-Aboriginal children. The association between daily maternal smoking and asthma-like symptoms, which has been mainly reported for children living in urban areas, was observed in Aboriginal and non-Aboriginal children living in northern and remote communities in Canada.

Background: To address the increasing age of pertussis cases, Yukon replaced the Grade 9 tetanus/diphtheria/inactivated polio booster with diphtheria/tetanus/acellular pertussis (dTap) and implemented a dTap catch-up program for Grade 12 students. The program began in June 2004, making Yukon one of the first Canadian jurisdictions to introduce dTap within five years of a tetanus booster. We implemented enhanced surveillance to monitor adverse events following immunization (AEFI) to determine whether students receiving dTap > or =3 to <5 years after their last tetanus booster were at increased risk of severe AEFI., Methods: Students completed a self-administered AEFI questionnaire one week post-dTap vaccination. Public health professionals contacted students reporting severe AEFI. Health care providers were requested to report AEFI. Symptom rate, severity and duration were compared between students receiving dTap > or =3 to <5 years after their last tetanus booster and those receiving it >5 years later., Results: The > or =3 to <5 years group was more likely than the > or =5 years group to report pain at the injection site (70.6% vs. 61.5%, p=0.038) and less likely to report injection site redness (10.0% vs. 17.3%, p=0.022), injection site swelling (8.9% vs. 16.4%, p=0.013), decreased energy (10.0% vs. 17.1%, p=0.023), body aches (2.2% vs. 7.2%, p=0.014) and sore joints (3.3% vs. 10.1%, p=0.004). Severe AEFI did not differ between the groups (3.3% vs. 5.6%, p=0.232). Health care professionals reported no AEFI., Conclusions: Results suggest no increased risk of severe AEFI among students receiving dTap > or =3 to <5 years after their last tetanus booster.

Wolves (Canis lupus) were captured in several geographic areas of Alaska (USA) and the Yukon Territory (Canada) during 1984-2000. Blood was collected from 1,122 animals. Sera were tested for antibodies against infectious canine hepatitis virus (ICH), canine distemper virus (CDV), canine parvovirus (CPV), Francisella tularensis, and serovars of Leptospira interrogans. Antibody prevalence for ICH was >84% for all areas. Area-specific prevalences of antibodies ranged from 12% to 70% for CPV, from 0% to 41% for CDV, and from 4% to 21% for F. tularensis. There was no evidence of CDV exposure at the two southernmost locations in Alaska. Prevalence of antibodies for ICH increased slightly during the 16-yr course of the survey. There was essentially no evidence of exposure to L. interrogans. Prevalences of antibodies for both CPV and CDV were age-specific, with higher values in the adult cohort compared with the pup cohort. There were no sex-specific differences in prevalence of antibodies for any of the five disease agents.

We investigated a large summertime outbreak of acute respiratory illness during May-September 1998 in Alaska and the Yukon Territory, Canada. Surveillance for acute respiratory illness (ARI), influenza-like illness (ILI), and pneumonia conducted at 31 hospital, clinic, and cruise ship infirmary sites identified 5361 cases of ARI (including 2864 cases of ILI [53%] and 171 cases of pneumonia [3.2%]) occurring primarily in tourists and tourism workers (from 18 and 37 countries, respectively). Influenza A viruses were isolated from 41 of 210 patients with ILI at 8 of 14 land sites and 8 of 17 cruise ship infirmaries. Twenty-two influenza isolates were antigenically characterized, and all were influenza A/Sydney/05/97-like (H3N2) viruses. No other predominant pathogens were identified. We estimated that >33,000 cases of ARI might have occurred during this protracted outbreak, which was attributed primarily to influenza A/Sydney/05/97-like (H3N2) viruses. Modern travel patterns may facilitate similar outbreaks, indicating the need for increased awareness about influenza by health care providers and travelers and the desirability of year-round influenza surveillance in some regions.

Teen pregnancy has declined throughout North America in the 1990s. In Yukon Territory, Canada, teen pregnancy in the late 1990s was almost 40% lower than in the early 1990s. This rate of decline is significantly greater than most recently reported national rates of teen pregnancy decline in Canada and United States. Identifying possible causes of the Yukon decline may help policy makers and program managers plan and implement teen pregnancy prevention strategies. Data on Yukon teen pregnancy prevention initiatives were collected through numerous discussions and interviews with Yukon service providers, teens, and the general public between 1994 and 2001. Analysis of data demonstrates that multiple new initiatives spanning many sectors were implemented in the mid and late 1990s that could have contributed to the decline in Yukon teen pregnancy. A multi-dimensional approach to teen pregnancy prevention that included researching and evaluating family planning programs and policies before, during, and after implementation, increasing access to longer-acting hormonal contraceptives, providing continuing family planning medical education to health care providers and other youth service providers, subsidization of contraceptives, delivery of innovative family planning mass media campaigns, and delivery of ongoing sexual health education programs may have significantly contributed to the decline in Yukon teen pregnancy. Collaboration among service providers across many service sectors (clinical, public health, education, First Nations, government communication and policy, grassroots) facilitated coordination of the multi-dimensional approach.

On June 18, 1999, CDC and Health Canada received reports from public health authorities in Alaska and the Yukon Territory about clusters of febrile respiratory illness and associated pneumonia among travelers and tourism workers. This report presents information about the outbreak. Laboratory evidence, including rapid influenza A antigen-detection tests and viral cultures from respiratory specimens, has implicated influenza A virus as the cause of illness.

On July 26, 1998, CDC and Health Canada, in cooperation with local public health authorities, began investigating reports of febrile respiratory illnesses and associated pneumonia among summer land and sea travelers to Alaska and the Yukon Territory (1). Epidemiologic and laboratory evidence has implicated influenza A virus as the etiologic agent of the outbreak. From June 11 through August 22, completed viral cultures of 101 (48%) of 209 nasopharyngeal specimens have yielded 26 influenza A isolates, four other respiratory viruses, and 71 negative results; results are pending for 108 additional specimens. Of the 26 influenza A isolates, five have been characterized at CDC; all have been identified as influenza A/Sydney/5/97 (H3N2)-like viruses, a strain included in the 1998-99 influenza vaccine. This report presents updated information about the outbreak and includes recommendations for influenza A prevention and control in this setting.

Since July 26, CDC and Health Canada, in cooperation with local public health authorities, have been investigating reports of febrile respiratory illness and associated pneumonia among persons traveling on land and sea, both independently and on tour packages, in Alaska and the Yukon Territory. Commonly reported symptoms include fever and cough, and laboratory evidence suggests that influenza A infection may be a cause of many of the illnesses. Summertime outbreaks of influenza A have previously been reported among tourists in the United States and Canada. No evidence suggests increased respiratory illness activity among residents of these areas.

Objectives: This article examines differences in health status and health determinants between residents of the North (Yukon and Northwest Territories) and of the provinces, and between Aboriginal and non-Aboriginal territorial residents. The use of health services and medications is also analyzed., Data Source: The data are from the 1994/95 National Population Health Survey (NPHS), both the territorial and provincial components. The population analyzed consists of household residents aged 12 and older., Main Results: Compared with non-Aboriginal Northerners, Aboriginal people in the territories more frequently rated their health poorly. However, they reported fewer injuries and diagnosed chronic conditions. The prevalence of alcohol consumption was lower among Aboriginal people, while the proportion of smokers was substantially higher. A lower proportion of Aboriginal territorial residents had consulted a general practitioner in the previous year, and a higher proportion had consulted a nurse. Aboriginal people also had a low rate of medication use.

Sixteen beluga whales (Delphinapterus leucas) and fifteen ringed seals (Phoca hispida) from the western arctic region of Canada were examined for giardiasis and cryptosporidiosis. Intestinal contents from the rectum and colon were collected from animals slaughtered by Inuit hunters. A fluorescent monoclonal antibody identified Giardia sp. cysts in three of 15 (20%) seals. Thus, ringed seals are implicated as a potential reservoir for this zoonosis in the arctic.

During 1990 the Yukon Bureau of Statistics conducted an alcohol and drug survey with a sample of 1,348 residents of the Territory, aged 15 and over. Over three-quarters of the sample reported experiencing at least one type of harm from others' drinking during the past year, and over a half experienced two or more types of harm. Among the main predictors of prevalence and extent of harm were respondents' age (younger), a greater number of drinks per occasion, close associates with alcohol problems, and residing in smaller communities. The results are discussed in terms of their relevance to identifying vulnerable groups and informing policy aimed at reducing alcohol use-related harm.

From July 1990 to February 1991, nematode numbers in free-ranging snowshoe hares (Lepus americanus) at Kluane Lake, southwestern Yukon, Canada, were manipulated by subcutaneous injection (0.4 mg/kg) of ivermectin. Three field experiments were conducted to determine the degree of helminth loss associated with a single administration of ivermectin; the length of time that ivermectin was effective in reducing worm numbers; and the effect of repeated ivermectin administration in reducing worm numbers. Numbers of the nematodes, Protostrongylus boughtoni and Nematodirus triangularis were reduced by approximately 80% 2 wk after treatment with a single dose of ivermectin, and were still significantly lower than controls at 4 wk. However, beyond 2 wk, ivermectin did not affect the rate of acquisition of new worms of either species. All treated groups contained one or more hares in which numbers of P. boughtoni and N. triangularis were not reduced. In addition, ivermectin had no effect on numbers of Trichuris leporis or Passalurus sp. Overall, ivermectin was not as effective against the nematodes of free-ranging hares as has been reported for nematodes of domestic and laboratory animals.

Several outbreaks of waterborne giardiasis have occurred in southern Canada, but nothing has been reported from the Canadian North. The objective of this study was to collect information relevant to waterborne giardiasis and cryptosporidiosis in the Yukon including epidemiological data and analyses of water, sewage, and animal fecal samples. Remote, pristine water samples were found to be contaminated with Giardia cysts (7 of 22 or 32%) but not with Cryptosporidium oocysts. Giardia cysts were found in 21% (13 of 61) of animal scats, but no Cryptosporidium oocysts were observed (small sample size). Whitehorse's drinking water was episodically contaminated with Giardia cysts (7 of 42 or 17%) and Cryptosporidium oocysts (2 of 42 or 5%). Neither were found in Dawson City's water supply. The only water treatment in the Yukon is chlorination, but contact times and free chlorine residuals are often too low to provide adequate protection by disinfection. Raw sewage samples from the five largest population centers in the Yukon contained 26 to 3,022 Giardia cysts and 0 to 74 Cryptosporidium oocysts per liter. Treated sewage from Whitehorse contained fewer Giardia cysts but more Cryptosporidium oocysts on average. Both were detected in Lake Laberge, downstream of Whitehorse, which has a history of fecal coliform contamination. Daily monitoring of raw sewage from the suburbs of Whitehorse showed a summertime peak of Giardia cysts and occasional Cryptosporidium oocysts after springtime contamination of drinking water. Despite this evidence, epidemiological data for the Yukon showed an endemic infection rate of only 0.1% for giardiasis (cryptosporidiosis is not notifiable).(ABSTRACT TRUNCATED AT 250 WORDS)

Three hundred thirty-three blue grouse (Dendragapus obscurus) were examined for blood parasites from 11 sites: southern Yukon Territory, southeast coastal Alaska, northern and central interior British Columbia, south coastal British Columbia, northcentral Washington, southcentral Oregon, northwestern California, eastcentral Nevada, northwestern Colorado, and westcentral Montana. Three species of protozoan parasites (Leucocytozoon lovati, Haemoproteus mansoni, Trypanosoma avium) and a splendidofilariid nematode (Microfilaria sp. B) were found in nearly all locations. Prevalence levels were consistently high for L. lovati (92%). The other hematozoa were found less frequently (H. mansoni 29%; T. avium 46%; and microfilaria 29%). The range of these parasites in blue grouse was extended to a more northern (Yukon Territory) and more southern distribution (Nevada than previously reported. Ranges were also extended to blue grouse populations in Alaska, Washington, Oregon and California.

We performed an anonymous seroprevalence survey of human immunodeficiency virus (HIV) type 1 infection through HIV antibody testing of blood samples from 22,512 women aged 15 to 44 years receiving prenatal care in British Columbia and the Yukon Territory from Mar. 15 to Sept. 30, 1989. Of the samples six were confirmed to be HIV positive; this yielded a crude overall seroprevalence rate of 2.7 per 10,000 pregnant women (95% confidence interval [CI] 1.0 to 5.8). All of the positive samples were from women 20 to 29 years of age; four were from Vancouver, one was from Victoria, and one was from elsewhere. The highest seroprevalence rates were among women aged 15 to 29 years in Vancouver and Victoria (7.2 and 9.4 per 10,000 pregnant women respectively). Thus, 1 in 1300 pregnant women in that age group in the metropolitan areas of British Columbia was HIV positive. Application of seroprevalence rates to the total female population in British Columbia and the Yukon Territory revealed that as many as 401 women had HIV infection in 1989. Our estimates likely represent the minimum. As a subset of women of childbearing age pregnant women are likely at lowest risk of HIV infection, and so the true number of women 15 to 44 years of age with HIV infection is probably several times higher. Our study has provided a baseline assessment and will be repeated annually to analyse trends in HIV seroprevalence among pregnant women in British Columbia and the Yukon Territory.