Respiratory health and its determinants among Nunavimmiut: results from the Qanuilirpitaa? 2017 Nunavik Health Survey.

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.

RéSUMé: OBJECTIFS: Les maladies respiratoires sont la première cause d'hospitalisation au Nunavik (Nord-du-Québec, Canada) et contribuent aux écarts d'espérance de vie avec le reste du Canada. Dans le cadre de l'enquête transversale et populationnelle Qanuilirpitaa? 2017, cette étude décrit la prévalence d'indicateurs de santé respiratoire et explore les caractéristiques qui leur sont associées. Elle fournit le premier estimé de la prévalence d'obstruction respiratoire par spirométrie dans la population inuite. MéTHODES: Les données de 1 296 participants âgés de 16 ans et plus ont été analysées par régression logistique multivariée pour évaluer les caractéristiques associées avec le wheezing (dans la dernière année), la toux chronique (durant au moins 3 mois) et l'obstruction bronchique (mesurée par spirométrie). RéSULTATS: Dans cette population relativement jeune (83 % entre 16 et 54 ans), les prévalences de wheezing, de toux chronique et d'obstruction bronchique étaient de 27 % (IC95% 24-30), 21 % (18-23) et 17 % (14-20). Ces estimés pourraient être biaisés puisque le taux de participation à l'enquête était relativement faible (environ 37 %). Les associations les plus fortes et consistantes sont observées avec le tabagisme (≥ 15 paquets-années; RC 3,13, 3,39 et 2,86 pour les trois indicateurs, respectivement) et avec la sécurité alimentaire (RC 0,55 avec le wheezing et 0,26 avec la toux chronique), définie à partir du Module d'enquête sur la sécurité alimentaire des ménages. Le wheezing était notamment associé avec la sensibilisation allergique aux chiens (2,60) et l'obésité (2,18). La toux chronique était associée avec les infections respiratoires sévères dans l'enfance (2,12), un logement ayant besoin de réparations majeures (1,72) et un logement surpeuplé (1,50); tandis que participer aux activités traditionnelles (0,62) et aller souvent dans la nature (0,64) semblaient protecteurs. L'obstruction bronchique était associée avec un faible indice de masse corporelle (3,84) et un niveau de scolarité postsecondaire (0,40). Le wheezing était aussi associé avec le fait d'avoir déjà inhalé des solvants chez les jeunes adultes (2,62) et chez les femmes (1,56), tandis que l'obstruction bronchique était associée avec la consommation régulière de cannabis chez les jeunes adultes (2,22) et chez les femmes (1,84). CONCLUSION: Le tabagisme et l'insécurité alimentaire sont fort prévalents et fortement associés avec des symptômes respiratoires au Nunavik. En plus de rappeler l'importance de la prévention du tabagisme, ces résultats supportent la pertinence des efforts communautaires et gouvernementaux pour résoudre les crises de l'insécurité alimentaire et du logement, améliorer les conditions socioéconomiques et promouvoir la culture inuite afin d'améliorer la santé respiratoire au Nunavik.

Epidemiology associated with the exposure to Toxoplasma gondii in Nunavik's Inuit population using the 2017 Qanuilirpitaa cross-sectional health survey.

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 = PRwoman/man ranged from 1.18 to 1.22), ecological region (PRHudsonBay/HudsonStrait ranged from 2.18 to 2.41; PRHudsonBay/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.

Previously undetected super-spreading of Mycobacterium tuberculosis revealed by deep sequencing.

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.

In Canada, tuberculosis disproportionately affects the Inuit, a group of indigenous people inhabiting the Arctic regions. Canada is aiming to eliminate tuberculosis among the Inuit by 2030. One way to help stop transmission and prevent future outbreaks is to trace how and where the disease spreads using DNA sequencing. This information can then be used by public health organizations to identify possible interventions. Typically, the DNA of the bacterium that causes tuberculosis ­ Mycobacterium tuberculosis, or Mtb for short ­ is sequenced 50­100 times and a consensus DNA sequence is then generated for each patient from this data. These consensus DNA sequences are then compared to help piece together who infected whom. Recently, scientists have realized that the bacteria a person is infected with may have different DNA sequences due to people being infected with more than one bacterium or the bacterium developing variations in its genome after the infection. However, current DNA sequencing practices may miss these differences, making it harder to trace how the disease spreads. Now, Lee et al. show that sequencing the DNA of Mtb from an infected person 500­1000 times (i.e. ∼10-20 times more than usual) makes it easier to detect genetic differences and determine how tuberculosis spreads. This approach, also known as 'deep sequencing', was used to analyze DNA samples of Mtb collected from about 50 people during an outbreak of tuberculosis in 2011-2012, which had previously undergone standard DNA sequencing. This deep sequencing approach identified a 'super-spreading event' where one person had likely transmitted tuberculosis to up to 17 others during the outbreak. Lee et al. found that most of these people had visited the same 'gathering houses' which are social venues in the community. Implementing targeted public health interventions at these sites may help stop future outbreaks. To fully understand how useful this method will be for tracking the spread of tuberculosis, deep and routine sequencing will need to be compared against each other in different settings and outbreaks. Furthermore, the approach used in this study may be useful for tracking the transmission of other infectious diseases.

The unique contribution of a local response group in the field investigation and management of a trichinellosis outbreak in Nunavik (Québec, Canada).

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.

Assessment of naturally acquired neutralizing antibodies against rabies Lyssavirus in a subset of Nunavik's Inuit population considered most at risk of being exposed to rabid animals.

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.

Limited impact of pneumococcal vaccines on invasive pneumococcal disease in Nunavik (Quebec).

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.

Characteristics of invasive Haemophilus influenzae serotype a (Hia) from Nunavik, Canada and comparison with Hia strains in other North American Arctic regions.

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.

Progression to tuberculosis disease increases with multiple exposures.

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.

Housing and tuberculosis in an Inuit village in northern Quebec: a case-control study.

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.

Cryptosporidium hominis Is a Newly Recognized Pathogen in the Arctic Region of Nunavik, Canada: Molecular Characterization of an Outbreak.

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.

Population genomics of Mycobacterium tuberculosis in the Inuit.

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.

Inadequate Diet Is Associated with Acquiring Mycobacterium tuberculosis Infection in an Inuit Community. A Case-Control Study.

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.

Reemergence and amplification of tuberculosis in the Canadian arctic.

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.

Uptake of pneumococcal vaccines in the Nordic region of Nunavik, province of Quebec, Canada.

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.

Characterizing rabies epidemiology in remote Inuit communities in Québec, Canada: a "One Health" approach.

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.

Impact of pneumococcal vaccines use on invasive pneumococcal disease in Nunavik (Quebec) from 1997 to 2010.

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.

Foodborne botulism in Canada, 1985-2005.

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.

Lead exposure in Nunavik: from research to action.

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.

From science to action and from action to science: the Nunavik Trichinellosis Prevention Program.

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.

Microbiological quality of blue mussels (Mytilus edulis) in Nunavik, Quebec: a pilot study.

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.