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Helicobacter pylori is a bacterium that may colonise and proliferate in human stomachs, leading invariably to chronic inflammation and, to a lesser extent, to peptic ulcers and cancer. The main objective of this study is to describe the epidemiology surrounding H. pylori in Nunavik's Inuit population using the 2004 and 2017 Health Surveys. Estimated prevalences were 70.9% for bacterial colonisation using a stool antigens test (SAT), 72.5% for anti- H. pylori antibodies, 12.7% for faecal occult blood in participants aged ≥ 50 and respectively of 28.4%, 11.2% and 2.4% for a prior diagnosis of colonisation, gastritis and peptic ulcer in the medical charts, with under five cases of gastric cancer reported. Variables associated with higher SAT+ prevalence were the number of household members (prevalence ratio [PR] = 1.03) and age (quadratic relationship), whereas mainly drinking municipal (PR = 0.84) and natural water (PR = 0.72) compared to bottled water, and increasing alcohol consumption (PR = 0.96) were associated with reduced prevalence. Despite current regional guidelines targeting high risk individuals in the context of high prevalence, Nunavik's health authorities must remain vigilant by following gastric cancer incidence and the rapid evolution of guidelines, while considering local realities.

Objectives: Respiratory diseases are the leading cause of hospitalization in Nunavik (northern Québec, Canada) and contribute to disparities in life expectancy with the rest of Canada. As part of Qanuilirpitaa? 2017, a cross-sectional population-based health survey, we sought to describe the prevalence of respiratory health indicators, including the first estimate of airway obstruction based on spirometry in an Inuit population, and explore their associated characteristics., Methods: We analyzed data from 1296 participants aged 16 years and older, using multivariate logistic regression to assess characteristics associated with spirometry-determined airway obstruction and self-reported respiratory symptoms, i.e., wheezing in the last year and chronic cough during at least 3 months., Results: In this relatively young population (83% aged 16 to 54), the prevalences of wheezing, chronic cough, and airway obstruction were, respectively, 27% (95% CI 24-30), 21% (18-23), and 17% (14-20). These estimates are prone to biases due to the relatively low participation rate (about 37%). The most consistent associations were with smoking (≥ 15 pack-years; odds ratio [OR] 3.13, 3.39, and 2.86 for the three indicators, respectively) and food security (OR 0.55 with wheezing and OR 0.26 with chronic cough), as defined in the Household Food Security Survey Module. Wheezing was also associated with allergic sensitization to dogs (2.60) and obesity (2.18). Chronic cough was associated with respiratory infections during childhood (2.12), housing in need of major repairs (1.72), and housing crowding (1.50), and was negatively associated with participation to traditional activities (0.62) and going on the land (0.64). Airway obstruction was associated with being underweight (3.84) and post-secondary education (0.40). Among young adults and women, wheezing was also associated with any inhalation of solvents for recreational purposes during their lifetime (2.62 and 1.56, respectively), while airway obstruction was associated with regular marijuana use (2.22 and 1.84, respectively)., Conclusion: Smoking and food insecurity are both highly prevalent and strongly associated with respiratory symptoms in Nunavik. Together with essential smoking prevention and cessation programs, our findings suggest that solving food security and housing crises, improving socioeconomic conditions, and promoting traditional lifestyle may improve respiratory health in Nunavik., (© 2023. The Author(s).)

Foci of high seroprevalence against Toxoplasma gondii are observed in Nunavik, the Inuit land of Northern Quebec (Canada). Considering the rare occurrence of felids in the region, exposure is suspected to be driven by water- and food-borne transmission routes. Hypotheses were that drinking untreated water from natural sources and eating country food mostly raw increased the risk of exposure to the parasite. Data from 1,300 Inuit participants of the 2017 Nunavik Health Survey were included in three weighted robust Poisson regression models. The effect of three types of exposure variables: (1) water treatment (yes/no) and if country food was mostly eaten raw (yes/no); (2) main source of drinking water (bottled/municipal/natural) and frequency of country food consumption (continuous) and (3) drinking water risk (low/intermediate/high) and frequency of a raw country food consumption (continuous), on the presence of Toxoplasma antibodies were estimated. Models were adjusted for age, sex and ecological region, with multiple sensitivity analyses being performed. Toxoplasma gondii seroprevalences were consistently correlated with age quadratically, sex (prevalence ratio = PR woman/man ranged from 1.18 to 1.22), ecological region (PR HudsonBay/HudsonStrait ranged from 2.18 to 2.41; PR HudsonBay/UngavaBay ranged from 1.52 to 1.59) and consuming bivalve mollusc/urchin (PR varied from 1.02 to 1.21) across all three models. Each increase of two consumptions per month of beluga (PR ranged from 1.01 to 1.03), seal liver (PR ranged from 1.01 to 1.02) and goose (PR ranged from 1.01 to 1.02) were also associated with seropositivity, albeit more clearly in models 2 and 3, while drinking water mainly from natural (PR of 1.47) or municipal (PR = 1.42) sources compared to bottled water, was correlated with seroprevalence, although results were compatible with the null. Our results suggest that both the oocyst- (mollusc/urchin, drinking water) and cyst-borne (walrus, seal liver and goose) transmission pathways could be present in Nunavik., (© 2021 Wiley-VCH GmbH.)

Background: Respiratory infections are a major health problem in the Inuit population of Nunavik, province of Quebec, Canada., Objectives: A study was undertaken to assess the burden of lower (LRTI) and upper respiratory tract infections (URTI) and otitis media (OM) and to explore some of their determinants including the pneumococcal conjugate vaccine (PCV) status., Methods: The reference population includes children less than 5 years of age born in 1994-2010 and a sample of 825 children was selected for this study. Outpatient medical records were reviewed. Visits with a diagnosis of LRTI, URTI and OM were extracted. Univariate and multivariate statistical analyses were performed to identify predictors of disease risk., Results: The average number of LRTI, URTI and OM episodes were, respectively, 2.6, 6.2 and 5.9 from birth up to the 5th birthday. Seasonal patterns were similar for URTI and OM, but was different for LRTI. Children who received the recommended 4 PCV doses had a lower LRTI and OM risk than unvaccinated children. There was a trend towards a lower OM risk associated with a mixed PCV10+ PCV13 schedule compared with PCV7., Conclusion: Results suggest a lower LRTI and OM risk associated with PCV use in this high-risk population but respiratory disease risk remains high compared with the general population in Quebec.

Tuberculosis disproportionately affects the Canadian Inuit. To address this, it is imperative we understand transmission dynamics in this population. We investigate whether 'deep' sequencing can provide additional resolution compared to standard sequencing, using a well-characterized outbreak from the Arctic (2011-2012, 50 cases). Samples were sequenced to ~500-1000x and reads were aligned to a novel local reference genome generated with PacBio SMRT sequencing. Consensus and heterogeneous variants were identified and compared across genomes. In contrast with previous genomic analyses using ~50x depth, deep sequencing allowed us to identify a novel super-spreader who likely transmitted to up to 17 other cases during the outbreak (35% of the remaining cases that year). It is increasingly evident that within-host diversity should be incorporated into transmission analyses; deep sequencing may facilitate more accurate detection of super-spreaders and transmission clusters. This has implications not only for TB, but all genomic studies of transmission - regardless of pathogen., Competing Interests: RL, JP, FM, MB, WH No competing interests declared, (© 2020, Lee et al.)

Setting: Consumption of raw game meats is important for Inuit health and well-being but may sometimes increase risk of exposure to parasites. In Nunavik, following trichinellosis outbreaks in the 1980s caused by raw walrus consumption, a diagnostic test was developed for the region and offered to all Inuit communities by 1997. Despite this prevention program, an important trichinellosis outbreak occurred in 2013, affecting 18 inhabitants of Inukjuak., Intervention: Because the classical outbreak investigation did not rapidly converge toward a common food source or specific event, a local response group, composed of four community members appointed by the Municipal Council as well as the regional public health physician, nurse and wildlife parasitologist, was created. Their objective was to investigate potential sources of infection related to the outbreak, hence the investigation of the types of meats consumed, the movement of meats between and within the community, and the local practices of processing game meat., Outcomes: Though the source of infection was not fully confirmed, this local investigation identified the distribution of transformed polar bear meat as the most probable source of infection. The creation of this unique, intersectoral and intercultural local response group fostered the use of local knowledge to better understand aspects of the modern food system, and is one of the most innovative outcomes of this investigation., Implications: Integrating multiple ways of knowing was critical for the management of this important public health issue and contributed to community members' mobilization and empowerment with respect to local food safety issues.

Contact with infected saliva through the bite of a rabid animal is the main route of infection with the rabies Lyssavirus in humans. Although a few individuals have survived the infection, rabies remains the most lethal zoonotic infection worldwide. Over the last century, the dogma that rabies is invariably fatal has been challenged by the survival and recovery of infected animals. In humans, 11 studies have found rabies virus-specific antibodies in unvaccinated individuals exposed to rabies virus reservoir species, suggesting the possibility of asymptomatic rabies virus infection, contact with non-infectious virus or exposure to the virus without viral replication. Two of these studies were conducted in Arctic hunters. Considering the extensive exposure of Nunavik's Inuit to potentially infected animals through hunting, trapping, skinning and the preparation of Arctic carnivores, we analysed archived serum samples from the 2004 Nunavik Inuit Health Survey for the presence of rabies virus-neutralizing antibodies (rVNA) in this sub-population. A total of 196 participants who were considered at highest risk for exposure to rabies virus were targeted. Serum samples were tested for the presence of rVNA using a variation of the fluorescent antibody virus neutralization test, an assay recommended for the quantification of neutralizing antibody titres following vaccination. Our study identified two seropositive individuals among the 196 participants but a review of their medical record and a phone interview revealed previous vaccination. Our results do not provide evidence for naturally acquired rVNA in Nunavik's Inuit population., (© 2019 Blackwell Verlag GmbH.)

Objective: In 2002, a mass immunization campaign using the 23-valent pneumococcal polysaccharide vaccine (PPV23) was carried out in Nunavik to control an outbreak caused by a virulent clone of serotype 1 Streptococcus pneumoniae. At the same time, the 7-valent pneumococcal conjugate vaccine (PCV7) was introduced for routine immunization of infants, replaced by the 10-valent vaccine (PCV10) in 2009, and the 13-valent vaccine (PCV13) in 2011. The objective of this study was to describe the epidemiology of invasive pneumococcal disease (IPD) in relation to pneumococcal vaccine use., Method: Retrospective analysis of IPD cases identified by the Quebec Public Health Laboratory during the period 1997-2016., Results: One hundred thirty-two IPD cases were identified during the study period. In adults, serotype 1 incidence decreased following the 2002 PPV23 mass campaign, but breakthrough cases occurred. Following PCV use, the incidence of vaccine-type IPD decreased markedly in children and also in adults but serotypes not covered by conjugate vaccines increased. The overall IPD rate was 43/100,000 person-years in the 1997-1999 pre-vaccine era and 58/100,000 person-years in 2010-2016., Conclusions: The 2002 PPV23 mass immunization campaign may have contributed to control the serotype 1 outbreaks in Nunavik, but its effect was short-lived as IPDs caused by serotypes included in this vaccine continued to occur after 2005. PCV use in children induced important modifications in the epidemiology of IPD, but most of the benefits were eroded by serotype replacement.

Background: A small village in Nunavik, Quebec experienced a tuberculosis (TB) outbreak in 2012-2013 and then a resurgence in 2015-2016. Cases were still occurring, despite the fact that contact tracing had already been conducted on one quarter of the population. A decision was taken to conduct large-scale screening of the population for TB., Objective: To describe the results of a population-based TB screening intervention designed to identify individuals with latent TB infection (LTBI) or active TB requiring treatment., Methodology: The history of TB infection (either active TB or LTBI, defined as a positive tuberculin skin test result of at least five mm induration) and treatment (considered adequate if at least 80% of prescribed doses were taken) were determined. Those who were two years of age and older and had not been included in contact tracing after June 1, 2015 were included for TB screening (n=1,026 eligible individuals). Screening included a nurse assessment, tuberculin skin test (TST) for those with previous negative TST or of unknown status and chest X-ray for the others., Results: Of the eligible individuals in the affected village, 1,004 (98%) participated in the screening. Of these, 30% had a history of previous TB infection. A TST screening was administered to 71% of the participants, 10% of whom had positive results. Assessments were performed on 425 participants and 385 underwent a chest X-ray. Fifty-two cases of previously diagnosed active TB and three cases of new active TB were documented. In addition, there were 247 individuals with LTBI who had been previously identified (191 were found to have had adequate LTBI treatment, 56 were found to have had inadequate LTBI treatment) and 69 were identified with de novo LTBI. In addition, 633 participants were found to have no TB infection. There were 125 participants who were referred for LTBI treatment. Follow-up information was available for 120 and 85 (71%) of these completed the treatment., Conclusion: Within this northern village, which had persistent TB transmission despite classic control measures, population-based screening had a high degree of coverage and was an effective way to detect additional cases of individuals with active TB and those with LTBI., Competing Interests: Conflict of interest: None.

Background: Otitis media (OM) constitutes an important public health problem in the Inuit population of Nunavik, Northern Quebec. One of the objectives of the childhood pneumococcal vaccination program is to reduce OM burden. The program was implemented in 2002, and 7-, 10-, and 13-valent conjugate vaccines were used sequentially, with doses offered at 2, 4, 6 and 12-18 months, respectively., Objective: To assess the prevalence of middle ear abnormalities at age 5 years in relation with exposure to different pneumococcal conjugate vaccines., Methods: Immunization cards and audiology screening tests at age 5 years of children born in 1994-2010 were reviewed. Children were classified according to the vaccine schedule recommended for their birth cohort or to the vaccines they actually received. Log-linked binomial regression models were used to assess the relative abnormalities risk according to different vaccination schedules., Results: Among 3517 children with complete documentation, the prevalences of minor and major abnormalities were 29% and 18%, respectively. Minor abnormalities frequency was higher in unvaccinated children (34%) and lower in children vaccinated with PCV7 (22%), PCV7 + PCV10 (17%), PCV10 (15%) and PCV10 + PCV13 (18%). No substantial differences among vaccine schedules were observed for major abnormalities., Conclusions: Pneumococcal conjugate vaccination was associated with a decreased frequency of middle ear abnormalities although no effect was seen for major abnormalities which may be trigger by OM with early onset. Clinicaltrials.gov registration number: NCT01694329., (Copyright © 2018. Published by Elsevier Ltd.)

Setting: The northern circumpolar jurisdictions Canada (Northwest Territories, Nunavik, Nunavut, Yukon), Finland, Greenland, Norway, Russian Federation (Arkhangelsk), Sweden and the United States (Alaska)., Objective: To describe and compare demographic, clinical and laboratory characteristics, including drug resistance and treatment completion, of tuberculosis (TB) cases in the northern circumpolar populations., Design: Descriptive analysis of all active TB cases reported from 2006 to 2012 for incidence rate (IR), age and sex distribution, sputum smear and diagnostic site characteristics, drug resistance and treatment completion rates., Results: The annual IR of TB disease ranged from a low of 4.3 per 100 000 population in Northern Sweden to a high of 199.5/100 000 in Nunavik, QC, Canada. For all jurisdictions, IR was higher for males than for females. Yukon had the highest proportion of new cases compared with retreatment cases (96.6%). Alaska reported the highest percentage of laboratory-confirmed cases (87.4%). Smear-positive pulmonary cases ranged from 25.8% to 65.2%. Multidrug-resistant cases ranged from 0% (Northern Canada) to 46.3% (Arkhangelsk). Treatment outcome data, available up to 2011, demonstrated >80% treatment completion for four of the 10 jurisdictions., Conclusion: TB remains a serious public health issue in the circumpolar regions. Surveillance data contribute toward a better understanding and improved control of TB in the north.

Objective: This study examines the microbiological characteristics of invasive Haemophilus influenae serotype a (Hia) isolates from Nunavik (northern Quebec), Canada. The relationship between invasive Hia isolates from Nunavik, Nunavut, Canada, and Alaska, USA will be discussed., Methods: Twenty invasive Hia isolates were recovered from patients in Nunavik from 2010 to 2013 and characterized by biotype, multi-locus sequence typing, IS1016-bexA deletion, antibiotic susceptibility and pulsed field gel electrophoresis (PFGE)., Results: All 20 Hia isolates were biotype II, sequence type -23, did not have IS1016-bexA deletions and were susceptible to all antibiotics tested. PFGE showed only two patterns, with 19 isolates giving identical molecular fingerprints, and the remaining isolate gave a PFGE pattern >95% similar., Conclusion: One major clone of Hia appears to be causing invasive disease in Nunavik, Canada. Based on previous studies, Hia from Nunavut were also typed as ST-23, while invasive Hia isolates from Alaska belonged to either ST-23 or closely related STs. Thus invasive Hia in the North America Arctic belonged to the ST-23 clonal complex and lacked the IS1016-bexA partial deletion., (Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.)

During a single year, a Canadian village had 34 individuals with microbiologically confirmed tuberculosis (TB) among 169 people with a new infection (20%). A contact investigation revealed multiple exposures for each person. We investigated whether the intensity of exposure might contribute to this extraordinary risk of disease.We carried out a case-control study using a public health database. Among those with a new infection, 34 had culture-confirmed TB (cases) and 118 did not progress to disease (controls). 17 patients with probable disease were excluded. Contact investigation data were utilised to tabulate the number of potential sources (total exposures). Generalised estimating equations with a logit link were used to identify associations between exposures and progression, and to investigate other potential risk factors.The median (interquartile range) number of total exposures was 15 (3-23) for cases and 3 (2-12) for controls (p=0.001). The adjusted OR for disease was 1.11 (95% CI 1.06-1.16) per additional exposure, corresponding to an OR of 3.4 for disease when comparing the medians of 15 versus 3 total exposures. This association increased when restricting to tuberculin skin test conversions.Increased exposure could be a marker of greater risk of progression to TB disease. Therefore, this risk may not be transportable across epidemiologic settings with variable exposure intensities., (Copyright ©ERS 2016.)

Background: Between November 2011 and November 2012, an Inuit village in Nunavik, Quebec experienced a surge in the occurrence of active TB; contact investigations showed that TB infection was highly prevalent (62.6%), particularly among those over age 14 years (78.8%). A nested case-control study showed that nutritional inadequacy was associated with acquisition of infection but not progression to disease. We performed a study to determine whether characteristics of one's dwelling were associated with 1) acquisition of newly diagnosed TB infection and 2) progression to confirmed or probable disease among those with TB infection., Methods: In this nested case-control study, we enrolled 200 people who were household or social contacts of at least 1 person with active TB or had received a diagnosis of active TB and assessed whether characteristics of their dwellings were associated with their odds of having newly diagnosed TB infection and/or odds of progression to disease between November 2011 and November 2012. For our first objective, we compared participants with newly diagnosed TB infection (regardless of their disease status) to a control group of contacts who were uninfected. For the second objective, we compared participants with confirmed or probable disease to a control group consisting of those with infection but no disease. We used information collected during investigation of the contacts and from study questionnaires to determine whether participants may have been exposed to TB in their own home (if they had shared a dwelling with someone who had smear-positive TB during the outbreak) or in other dwellings that they visited at least weekly., Results: The participants lived in 79 dwellings. The mean number of people per room was 1.1 (standard deviation [SD] 0.5). The mean room size and ventilation level of the common living space (kitchen and living/dining rooms) were 67.9 (SD 9.4) m3 and 1.69 (SD 0.26) air changes per hour, respectively. After adjustment for potential confounders, the number of people per room was positively associated with the odds of newly diagnosed infection and odds of disease, but only among participants who lived with someone with smear-positive TB (the minority of participants). Other dwelling characteristics were not associated with either outcome., Interpretation: Reducing household crowding may contribute to TB prevention. Overall, our investigations have not identified associations that explain the elevated disease risk in this village. In light of our results and considering the high prevalence of TB infection, treatment of latent infection is an essential intervention for long-term reduction of TB incidence in this village., Competing Interests: Conflicts of Interest: None declared.

Background: Cryptosporidium is a leading cause of childhood diarrhea in low-resource settings, and has been repeatedly associated with impaired physical and cognitive development. In May 2013, an outbreak of diarrhea caused by Cryptosporidium hominis was identified in the Arctic region of Nunavik, Quebec. Human cryptosporidiosis transmission was previously unknown in this region, and very few previous studies have reported it elsewhere in the Arctic. We report clinical, molecular, and epidemiologic details of a multi-village Cryptosporidium outbreak in the Canadian Arctic., Methodology/principal Findings: We investigated the occurrence of cryptosporidiosis using a descriptive study of cases with onset between April 2013 and April 2014. Cases were defined as Nunavik inhabitants of any age presenting with diarrhea of any duration, in whom Cryptosporidium oocysts were detected by stool microscopy in a specialised reference laboratory. Cryptosporidium was identified in stool from 51 of 283 individuals. The overall annual incidence rate (IR) was 420 / 100,000 inhabitants. The IR was highest among children aged less than 5 years (1290 /100,000 persons). Genetic subtyping for stool specimens from 14/51 cases was determined by DNA sequence analysis of the 60 kDa glycoprotein (gp60) gene. Sequences aligned with C. hominis subtype Id in all cases. No common food or water source of infection was identified., Conclusions/significance: In this first observed outbreak of human cryptosporidiosis in this Arctic region, the high IR seen is cause for concern about the possible long-term effects on growth and development of children in Inuit communities, who face myriad other challenges such as overcrowding and food-insecurity. The temporal and geographic distribution of cases, as well as the identification of C. hominis subtype Id, suggest anthroponotic rather than zoonotic transmission. Barriers to timely diagnosis delayed the recognition of human cryptosporidiosis in this remote setting.

Nunavik, Québec suffers from epidemic tuberculosis (TB), with an incidence 50-fold higher than the Canadian average. Molecular studies in this region have documented limited bacterial genetic diversity among Mycobacterium tuberculosis isolates, consistent with a founder strain and/or ongoing spread. We have used whole-genome sequencing on 163 M. tuberculosis isolates from 11 geographically isolated villages to provide a high-resolution portrait of bacterial genetic diversity in this setting. All isolates were lineage 4 (Euro-American), with two sublineages present (major, n = 153; minor, n = 10). Among major sublineage isolates, there was a median of 46 pairwise single-nucleotide polymorphisms (SNPs), and the most recent common ancestor (MRCA) was in the early 20th century. Pairs of isolates within a village had significantly fewer SNPs than pairs from different villages (median: 6 vs. 47, P < 0.00005), indicating that most transmission occurs within villages. There was an excess of nonsynonymous SNPs after the diversification of M. tuberculosis within Nunavik: The ratio of nonsynonymous to synonymous substitution rates (dN/dS) was 0.534 before the MRCA but 0.777 subsequently (P = 0.010). Nonsynonymous SNPs were detected across all gene categories, arguing against positive selection and toward genetic drift with relaxation of purifying selection. Supporting the latter possibility, 28 genes were partially or completely deleted since the MRCA, including genes previously reported to be essential for M. tuberculosis growth. Our findings indicate that the epidemiologic success of M. tuberculosis in this region is more likely due to an environment conducive to TB transmission than a particularly well-adapted strain.

Background: Tuberculosis predominantly affects socioeconomically disadvantaged communities. The extent to which specific dietary and lifestyle factors contribute to tuberculosis susceptibility has not been established., Methods: A total of 200 residents of a village in Northern Quebec were investigated during a tuberculosis outbreak and identified to have active tuberculosis, latent tuberculosis infection, or neither. Participants completed questionnaires about their intake of food from traditional and commercial sources, and provided blood samples. Adults were asked about recent smoking and drug and alcohol intake. Nutritional adequacy was evaluated with reference to North American standards. Multiple dietary, lifestyle, and housing factors were combined in a logistic regression model evaluating the contributions of each to disease and infection., Findings: After adjusting for potential confounding, new infection was associated with inadequate intake of fruit and vegetables (odds ratio [OR], 2.1; 95% confidence interval [CI], 1.03-4.3), carbohydrates (OR, 4.4; 95% CI, 1.2-16.3), and certain vitamins and minerals. A multivariable model, combining nutrition, housing, and lifestyle factors, found associations between new infection and inadequate fruit and vegetable intake (OR, 2.3; 95% CI, 1.0-5.1), living in the same house as a person with smear-positive tuberculosis (OR, 14.7; 95% CI, 1.6-137.3), and visiting a community gathering house (OR, 3.7; 95% CI, 1.7-8.3). Current smoking was associated with new infection (OR, 9.4; 95% CI, 1.2-72) among adults completing a detailed lifestyle survey., Interpretation: Inadequate nutrition was associated with increased susceptibility to infection, but not active tuberculosis. Interventions addressed at improving nutrition may reduce susceptibility to infection in settings where access to healthy foods is limited.

Background: Between November 2011 and November 2012, a Canadian village of 933 persons had 50 culture-positive cases of tuberculosis, with 49 sharing the same genotype., Methods: We performed Illumina-based whole-genome sequencing on Mycobacterium tuberculosis isolates from this village, during and before the outbreak. Phylogenetic trees were generated using the maximum likelihood method., Results: Three distinct genotypes were identified. Strain I (n = 7) was isolated in 1991-1996. Strain II (n = 8) was isolated in 1996-2004. Strain III (n = 62) first appeared in 2007 and did not arise from strain I or II. Within strain III, there were 3 related but distinct clusters: IIIA, IIIB, and IIIC. Between 2007 and 2010, cluster IIIA predominated (11 of 22 vs 2 of 40; P < .001), whereas in 2011-2012 clusters IIIB (n = 18) and IIIC (n = 20) predominated over cluster IIIA (n = 11). Combined evolutionary and epidemiologic analysis of strain III cases revealed that the outbreak in 2011-2012 was the result of ≥6 temporally staggered events, spanning from 1 reactivation case to a point-source outbreak of 20 cases., Conclusions: After the disappearance of 2 strains of M. tuberculosis in this village, its reemergence in 2007 was followed by an epidemiologic amplification, affecting >5% of the population., (© The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Rabies is endemic throughout arctic areas including the region of Nunavik, situated north of the 55th parallel of Québec, Canada, and raises public health concerns. The aim of this paper is to provide a descriptive overview of the temporal and regional distributions of three important components of arctic rabies in Nunavik from 1999 to 2012, following a "One Health" approach: animal rabies tests and confirmed cases, dog vaccination, and human consultations for potential rabies exposures. Forty-four cases of rabies, involving mainly arctic and red foxes, were confirmed in animals during this period. The mean number of dogs vaccinated per 1,000 inhabitants was highly variable and lower in the Hudson region than the Ungava region. 112 consultations for potential rabies exposure were analyzed, of which 24 were exposure to a laboratory confirmed rabid animal. Children less than 10 years of age were the age group most commonly exposed. The median time between potential exposure and administration of the first post-exposure prophylaxis dose was four days. This study confirms that the risk of human exposure to rabid animals in Nunavik is present and underlines the need to follow a "One Health" approach to prevent rabies in humans in similar contexts worldwide.

Objectives: Pneumococcal infections constitute an important public health problem in Nordic regions of Canada. Nordic populations are not included in national and provincial immunization surveys and there is no centralized immunization registry in these regions. The objective of this study was to estimate pneumococcal vaccination coverage and delays in immunization of children in Nunavik, Quebec., Methods: Immunization records of children born in 1994-2005 were collected in all villages. Children were classified into three groups: born in the period January 1, 1994 to April 30, 1997 and targeted by the 2002 mass campaign with the 23-valent polysaccharide vaccine (PPSV23); born in the period May 1, 1997 to March 31, 2002 and targeted by the 7-valent conjugate vaccine (PCV7) catch-up campaign; born in the period April 1, 2002 to December 31, 2005 and targeted by the PCV7 routine infant program., Results: In the first group (n=896), 86.8% (95% CI: 84.4%-89.0%) were vaccinated with PPSV23. In the second group (n=1,252), 84.3% (95% CI: 82.1%-86.2%) received ≥1 PCV7 dose. In the third group, 90.4% (95% CI: 88.5%-92.1%) received 4 PCV7 doses. Delays >4 weeks in vaccine administration were observed for 26.3% of doses. There were substantial variations between villages for all indicators., Conclusions: In the challenging setting of a Nordic and remote region, uptake rates of pneumococcal vaccines in Nunavik were found to be similar to those measured in population surveys in Quebec.

Background: In 2000, an outbreak of severe pneumonia caused by a virulent clone of serotype 1 Streptococcus pneumoniae was detected in the Nunavik region of Quebec. A mass immunization campaign was implemented in the spring of 2002, targeting persons ≥5 years of age and using the 23-valent pneumococcal polysaccharide vaccine (PPSV23). At the same time, the 7-valent pneumococcal conjugate vaccine (PCV7) was introduced into the routine immunization programme of infants, with catch-up for children up to 4 years of age., Objectives: To describe the epidemiology of invasive pneumococcal disease (IPD) in relation to PPSV23 and PCV7 use., Study Design and Methods: Retrospective analysis of IPD cases identified by the Quebec public health laboratory during the period 1997-2010., Results: A total of 82 IPD cases were identified during the study period. In adults, serotype 1 incidence decreased following the 2002 PPSV23 mass campaign but breakthrough cases continued to occur. Following PCV7 use in children, there was a decrease in the incidence of vaccine-type IPD and replacement by other serotypes in adults. In children, a marked decrease in the annual incidence of serotypes included in PCV7 was observed following PCV7 introduction: 162/100,000 in 1997-2001 vs. 10/100,000 in 2004-2010 (p<0.01). Concomitantly, the incidence of IPD caused by serotypes not included in PCV7 increased from 29/100,000 to 109/100,000 (p=0.11)., Conclusion: The mass immunization campaign using the PPSV23 in 2002 and the introduction of PCV7 for the routine immunization of infants induced important modifications in the epidemiology of IPD. IPD rates in Nunavik remain much higher than in the southern part of the province both in children and adults. More effective pneumococcal vaccines are needed to eliminate geographic disparities in IPD risk.

During 1985-2005, a total of 91 laboratory-confirmed outbreaks of foodborne botulism occurred in Canada; these outbreaks involved 205 cases and 11 deaths. Of the outbreaks, 75 (86.2%) were caused by Clostridium botulinum type E, followed by types A (7, 8.1%) and B (5, 5.7%). Approximately 85% of the outbreaks occurred in Alaska Native communities, particularly the Inuit of Nunavik in northern Quebec and the First Nations population of the Pacific coast of British Columbia. These populations were predominantly exposed to type E botulinum toxin through the consumption of traditionally prepared marine mammal and fish products. Two botulism outbreaks were attributed to commercial ready-to-eat meat products and 3 to foods served in restaurants; several cases were attributed to non-Native home-prepared foods. Three affected pregnant women delivered healthy infants. Improvements in botulism case identification and early treatment have resulted in a reduction in the case-fatality rate in Canada.

Background: In 1999, the Government of Canada regulated the use of lead shot for hunting. Concurrently, the Nunavik Regional Board of Health and Social Services (NRBHSS) was informed of the results of an isotope study that pointed to lead ammunition as a likely source of lead exposure in Nunavik. Rapidly thereafter, a coalition for the banning of lead shot was implemented by the NRBHSS as well as by regional/local partners and by Inuit hunters in order to disseminate this information to the public., Objectives: The purpose of this article is to describe the intervention conducted in the winter of 1999 by the NRBHSS and to assess the combined impact of national legislation and an awareness campaign on blood lead levels in Nunavik., Study Design: Impact assessment of the intervention for the banning of lead shot conducted in 1999 in Nunavik using blood lead levels data before and after the intervention., Methods: Data on blood lead levels in Nunavik describing foetal exposure as well as during childhood and in adults published between 1992 and 2009 were compiled. Blood lead levels in Nunavik prior to and after the interventions were compared. To assess the current situation, the most recent blood lead levels were compared with those from surveys conducted during the same period in North America., Results: Analysis of blood samples collected from umbilical cord and from adults show that blood lead levels in Nunavik significantly declined between 1992 and 2004. Nevertheless, lead exposure in Nunavik still remains higher in comparison to that observed in other North American surveys., Conclusions: The current situation regarding lead exposure in Nunavik has significantly improved as a result of the implemented intervention. However, according to recent data, a gap still subsists relative to other North American populations.

Objectives: During the 1980s, walrus-meat consumption caused infections with the parasite Trichinella nativa in Nunavik inhabitants. In response to these events, stakeholders set up the community-based Nunavik Trichinellosis Prevention Program (NTPP). The objectives of the present communication are to review the NTPP, describe how science and action were interwoven in its development and identify its assets and limitations. Study design. Descriptive study., Methods: The NTPP relies on a pooled digestion assay of tongue samples taken from each harvested walrus. The public health recommendations depend on the results of the analyses: infected walrus meat should be destroyed; parasite-free meat may be eaten raw or cooked., Results: All communities involved in the walrus hunt participate in the NTPP and a high percentage of harvested walruses are included in the NTPP. Infected animals account for 2.9% of the walruses tested (20/694) since 1992. The NTPP permitted the early management of a trichinellosis event in 1997. Since then, it prevented the new occurrence of outbreaks related to walruses hunted by Nunavimmiut., Conclusions: The absence of recent major outbreaks of trichinellosis in Nunavik may reasonably be attributed to the NTPP. The success of the program stands on many facilitating factors such as the nature of the disease and its source, the existence of an efficient analytic method, the strong involvement of the different partners including direct resource users, as well as the comprehensive bidirectional science-to-action approach that has been followed.

In Nunavik, common practices and food habits such as consumption of raw meat and untreated water place the Inuit at risk for contracting zoonotic diseases. The aim of this study was to determine the seroprevalence of seven zoonotic infections among the permanent residents of Nunavik. The study was conducted in the fall 2004 as part of the Nunavik Health Survey. Blood samples from adults aged 18-74 years (n = 917) were collected and analysed for the presence of antibodies against Trichinella spp., Toxocara canis, Echinococcus granulosus, Brucella spp., Coxiella burnetii, Leptospira spp. and Francisella tularensis. Information on sociodemographic characteristics, traditional activities, drinking water supply and nutrition was gathered using english/inuktitut bilingual questionnaires. The chi-squared test was used to evaluate associations between seropositivity and other measured variables. Statistically significant variables were included in a multivariate logistic regression model to control for confounding factors. Estimated seroprevalences were 8.3% for E. granulosus, 3.9% for T. canis, 5.9% for Leptospira spp. and 18.9% for F. tularensis. Seroprevalence was ≤ 1% for Trichinella spiralis, Brucella spp. and C. burnetii. For most infections, seropositivity tended to increase with age. In multivariate analyses, seroprevalence was positively (i.e. directly) associated with age and residence in the Ungava coast area for F. tularensis; age and residence in the Hudson coast area for T. canis; female gender, lower level of schooling and frequent cleaning of water reservoirs for E. granulosus. No risk factor for Leptospira spp. infection was identified. No associations were detected with regards to food habits or environmental exposures. A small but significant portion of the Nunavik population has serologic evidence of exposure to at least one of the pathogenic microorganisms investigated. Further studies are needed to better understand the mechanisms for transmission of zoonotic infections and their potential reservoirs in Nunavik., (© 2011 Blackwell Verlag GmbH.)

Toxoplasmosis is a significant public health threat for Inuit in the Canadian Arctic. This study aimed to investigate arctic seals as a possible food-borne source of infection. Blood samples collected from 828 seals in 7 Canadian Arctic communities from 1999 to 2006 were tested for Toxoplasma gondii antibodies using a direct agglutination test. Polymerase chain reaction (PCR) was used to detect T. gondii DNA in tissues of a subsample of seals. Associations between seal age, sex, species, diet, community and year of capture, and serological test results were investigated by logistic regression. Overall seroprevalence was 10·4% (86/828). All tissues tested were negative by PCR. In ringed seals, seroprevalence was significantly higher in juveniles than in adults (odds ratio=2·44). Overall, seroprevalence varied amongst communities (P=0·0119) and by capture year (P=0·0001). Our study supports the hypothesis that consumption of raw seal meat is a significant source of infection for Inuit. This work raises many questions about the mechanism of transfer of this terrestrial parasite to the marine environment, the preponderance of infection in younger animals and the natural course of infection in seals. Further studies to address these questions are essential to fully understand the health risks for Inuit communities.

This pilot study was aimed at documenting the presence of fecal indicators and enteric pathogens in blue mussels (Mytilus edulis) from 6 communities in Nunavik, Quebec. One to four 2 kg samples of mussels were collected at low tide in each community. Samples were investigated by enumeration methods for the fecal indicators enterococci, Escherichia coli, F-specific coliphages, Clostridium perfringens, and by molecular identification for the pathogens norovirus, Salmonella spp., Campylobacter jejuni, Campylobacter coli, and Campylobacter lari, verocytotoxin-producing E. coli (particularly serovar O157:H7), Shigella spp., and Yersinia enterocolitica. In 5 communities, the presence of Giardia duodenalis and Cryptosporidium spp. was also tested by microscopy and molecular methods and that of Toxoplasma gondii was tested by molecular methods. Apart from small quantities of Clostridium perfringens in 2 samples, no bacterial or viral pathogens were detected in the mussels. Toxoplasma gondii was also not detected. However, G. duodenalis and Cryptosporidium spp. were present in 18% and 73% of the samples investigated for these pathogens, respectively. When considering the indicators and the viral and bacterial pathogens investigated, the mussels examined were of good microbiological quality, but considering the presence of potentially zoonotic protozoa, it should be recommended that consumers cook the molluscs well before eating them.

As a result of their intimate contact with the land and their nutritional habits, the Inuit of Nunavik are considered to be at risk from zoonotic infections. To better understand the risk factors for Toxoplasma gondii infection, a serosurvey was conducted in Nunavik, Québec, in September 2004. A representative sample of the Inuit adult population of Nunavik participated in this cross-sectional study (n = 917). Antibodies (IgG) against T. gondii were detected by immunoassay. Information on sociodemographic characteristics, traditional activities, domestic environment and nutrition was gathered by questionnaire and explored as variables explanatory of seropositive results. Associations found to be statistically significant in univariate analyses were assessed by multivariable logistic regression to control for confounding factors. Almost two thirds (59.8%) of the Inuit of Nunavik were found to be seropositive for T. gondii. In multivariate analyses, risk factors for seropositivity were: increasing age, gender (women > men), lower level of education, consumption of potentially contaminated water (determined by an index of risk from waterborne infections), frequent cleaning of water reservoirs, and consumption of seal meat and feathered game. There was some variation in seroprevalence between the Ungava Bay coast (52.3%) and the Hudson Bay coast (65.6%), the two main regions of Nunavik, but this variation was not significant in the multivariable logistic regression model. This cross-sectional study demonstrated high T. gondii seroprevalence in the Inuit population and revealed that age, gender, schooling and community of residence all influence serostatus in this population. Variables related to drinking water and food choices may also influence the risk of infection. These results raise important questions about T. gondii transmission in Nunavik including possible links between terrestrial and marine cycles.

Objectives: (1) To evaluate the efficacy of the Toxoplasma gondii screening program among Nunavik pregnant women in identifying seroconversions during pregnancy and performing an appropriate follow-up of the seroconverted women and their child; and (2) to evaluate the consequences of congenital Toxoplasma gondii infection., Participants: Women of child-bearing age and their children born between January 1994 and September 2003., Setting: Nunavik., Intervention: Potential cases of infection during pregnancy and of congenital toxoplasmosis were identified on the basis of serologic and hospitalization data. A medical chart revision was then performed. Descriptive statistics regarding the medical follow-up and treatment of suspected cases were compiled., Outcomes: 31 women who gave birth to 32 children were identified as potential cases. According to the medical charts, 19 women had a potential infection during pregnancy, the others were deemed to have been infected before conception. One woman had a definite infection. This woman and most of the 18 other potentially infected women and their children were treated appropriately. Because of missing data, it was impossible to determine with certainty the final status of two children. A diagnosis of congenital infection was rejected among the other children., Conclusion: Women with suspected infection and their children were generally well managed by the health care system. No clinical effect of congenital toxoplasmosis was noted during the studied period.

Objectives: In spring 2002, a mass immunization campaign using a 23-valent pneumococcal polysaccharide vaccine (23-PPV) was launched in order to control an outbreak of severe pneumonia caused by a virulent clone of serotype 1 Streptococcus pneumoniae in Nunavik, Quebec, Canada. The objective of the study was to evaluate the impact of this campaign on the incidence of invasive pneumococcal disease (IPD) and hospitalizations possibly associated with pneumococcal infections (HPAPI) in the mostly Inuit population aged 10 to 64 years., Study Design: Retrospective analysis of surveillance and administrative data., Methods: Multivariate Poisson model comparing the frequency rates of selected outcomes before the outbreak, during the outbreak, and after implementation of the mass immunization program., Results: The reported incidence of serotype 1 IPD decreased markedly after the implementation of the vaccination campaign (rate ratio = 0.16; p < 0.002). The frequency of HPAPI and the mean duration of hospital stay also decreased. However, vaccine failures were documented and the HPAPI rate remained higher than in the period prior to the outbreak., Conclusions: Although 23-PPV contributed to control the outbreak, better vaccines are needed for the prevention of infections caused by serotype 1 S. pneumoniae.

This study evaluated the infectivity of Trichinella nativa in freshly frozen walrus meat and traditionally aged walrus meat (igunaq) associated with two human outbreaks of trichinellosis in the Canadian Arctic. Trichinella larvae recovered from walrus meat stored at -20 degrees C for up to 20 months remained infective for guinea pigs inoculated with 135 or 716 larval doses. However, none of the 4-5 and 10-month-old igunaq preparations contained infective T. nativa larvae as measured by bioassays using mice and guinea pigs at inoculation doses ranging from 6 to 500 larvae. This indicates that the degradation process that occurred in the field can be sufficient to either kill Trichinella larvae or render them non-infective for mice and guinea pigs. Further research is needed to evaluate the food safety risk of traditional walrus igunaq aged under different field conditions and storage times.

Objectives: Hearing loss is highly prevalent among Inuit children in Canada. Hearing screening at kindergarten age has been carried out in Nunavik by trained Inuit technicians since 1986. In this study, we determined what percentage of children fail their initial hearing screening at age 5-6 years and compared this initial result with the last hearing test. We also report the type of hearing loss observed at the last test., Methods: Results compiled in a clinical database were analysed. At age 5-6 years, 524 children (born 1990-1994, 84% coverage) were tested and 515 children were retested at a later date. Screening failure was defined as >22 dB pure tone average (.5k, 1k, 2kHz) in either ear. Observations on ear condition at the last test were used to determine type of hearing loss., Results: Nineteen percent (101 children) failed the hearing screening at age 5-6 years and 12% failed on the later test. When those who failed the first test were retested, 58 had improved and 43 remained with a hearing loss. Twenty-one children who had initially passed the hearing screening were found to have a hearing loss at retest. The majority of the hearing losses were due to otitis media., Conclusion: Hearing screening and retesting remains necessary due to the high prevalence of hearing loss found in this population and the fluctuating nature of this problem.

Objectives: Chronic otitis media (COM) and associated hearing loss is a frequent problem for many Inuit children in Canada. In this study, we evaluated individuals aged 12-16 years living in Inukjuak, to determine the prevalence of middle ear disease and hearing loss, and the effect of hearing loss on academic performance., Methods: Otological examination, hearing test, medical and school file review were performed in November 1997. 88 individuals were seen., Results: Otological examination revealed maximal scarring in 1.8%, minimal scarring in 34.9%, normal eardrums in 49.1% and chronic otitis media in 16.9%. There were 62 individuals whose ear exams could be directly compared with a previous exam done in 1987. Of those, there were three ears that had developed COM and 4/13 ears with COM in 1987 that had healed. Hearing tests found bilateral normal hearing in 80% (PTA <20dB), unilateral loss in 15% and bilateral loss in 5%. Hearing loss was associated with poorer academic performance in Language (p<.05). A similar trend was found in Mathematics but not in Inuttitut., Conclusion: Chronic otitis media remains a significant problem among the Inuit, with a prevalence of 16.9% in individuals aged 12-16 years. One in five in this age group has hearing loss, and this hearing loss impacts on academic performance.

In low-incidence countries targeting tuberculosis (TB) elimination, TB remains a problem of a few high-risk groups. In Canada, Aboriginals, and particularly the Arctic Inuit communities, have witnessed dramatic decreases in TB during the 1960s to 1970s, but rates remain at least 10 to 20 times higher than the national average. We are describing the results of an integrated traditional and molecular epidemiology study of all culture-positive Mycobacterium tuberculosis cases in the Arctic Inuit communities of Quebec from 1990 until 2000. The demographic characteristics of the 46 TB cases included in the study were most notable for a bimodal age distribution (48% under 25 years). Genotyping analysis using multiple modalities (IS6110 restriction fragment length polymorphism, spoligotype, mycobacterial interspersed repetitive units-variable number tandem repeats) showed that 76% (35/46) of TB cases were clustered (six clusters, median size four cases) and estimated that at least 62.5% of TB cases were due to ongoing transmission. By integrating the epidemiologic and genotyping data, we observed that the genotyping clustering results were concordant with recognized epidemiologic links but most notably identified previously unrecognized intervillage transmission. This study demonstrates significant ongoing transmission in a geographically isolated, low-density population. In a resource-rich country such as Canada, these communities illustrate some of the persistent challenges of TB control and elimination.

Analyses completed on samples collected between 1993 and 1996 showed that about 7% of 475 Inuit newborns from northern Quebec (Canada) had a cord blood lead concentration equal to or greater than 0.48 micromol/l, an intervention level adopted by many governmental agencies. A comparison between the cord blood lead isotope ratios of Inuit and southern Quebec newborns showed that lead sources for these populations were different. Our investigation suggests that lead shots used for game hunting were an important source of lead exposure in the Inuit population. A cohort study conducted in three Inuit communities shows a significant decrease of cord blood lead concentrations after a public health intervention to reduce the use of lead shot. Lead shot ammunition can be a major and preventable source of human exposure to lead.

Repeated outbreaks of trichinellosis caused by the consumption of Trichinella-infected walrus (Odobenus rosmarus) meat, which have sometimes led to serious morbidity, have stimulated Inuit communities in Nunavik (northern Quebec), Canada, to develop an innovative trichinellosis prevention program. The program involves preconsumption testing of meat samples from harvested walrus at a regional laboratory and the rapid dissemination of the results of such testing to communities. Local health authorities in Inukjuak conducted an epidemiological investigation after testing identified Trichinella-positive walrus meat in September 1997. This report describes the events that occurred before, during, and after the trichinellosis outbreak and also documents how the prevention program contributed to successful resolution of the outbreak.

The prevalence of middle ear disease in 2-6 year old children in 1997 was compared with that observed in 1987 in the same Inuit community in northern Quebec. Risk and protective factors associated with middle ear disease were also assessed. A total of 122 children participated. The assessments included: otological examination, cerumen sampling for analysis of organochlorine compounds, medical file review, and parent questionnaire regarding environmental and lifestyle factors. Comparison of ear examination results in 1997 and 1987 showed that there had been no change in the prevalence of chronic otitis media [9.4% to 10.8%] and proportion of ear drums with minimal scarring [45.6% to 45.4%], an increase in the proportion of normal ear drums [23.9% to 39.0%], a decrease the proportion with maximal scarring [17.8% to 2.0%] and little difference in the rate of serous otitis media [3.3% to 2.8%]. Factors found to be significantly associated with middle ear disease included: number of persons/bedroom, number of siblings with a history of ear disease, age at first, second and third visit to the nursing station for ear problems, and type of milk (formula vs. non-formula) in bottle fed children.

A large outbreak of trichinosis acquired from walrus in Salluit in 1987 provided the immunologic and epidemiologic data from which two distinct clinical syndromes were identified. The first syndrome is the classic myopathic form with edema, fever, myalgia, and rash. The second is a persistent diarrheal illness with little edema or myalgia. The clinical presentations are paralleled by distinct differences in type and development of antibody response. The clinical and serologic profiles of the two syndromes support the hypothesis that the myopathic form represents a primary infection of Trichinella nativa, while the second represents a secondary infection in previously sensitized individuals.