[Nutritional status of children in rural areas of the Komi Republic and Khanty-Mansi Autonomous Okrug - Yugra by anthropometric data].

A characteristic feature of the "global obesity epidemic" in recent decades is the rapid spread of overweight among the rural population. However, there is a lack of objective data on how this process is unfolding in the northern and Arctic regions of the Russian Federation. The aim of the work was to analyze the prevalence of malnutrition and rates of overweight and obesity in children living in Khanty-Mansi Autonomous Okrug - Yugra (KhMAO) and the Komi Republic (KR). Material and methods. We conducted a study of the nutritional status of rural children in the northern regions of the Russian Federation in 2018-2019. The subjects of the study were children aged 3-17 years of KhMAO, ethnic Khanty, Mansi and of various non-indigenous descent in small remote settlements (n=302) and 956 children in the administrative center of the northern district, a town-type residency. We also examined 7-17-year-old children (n=628) in large settlements of the KR, over 90% of them were ethnic Komi. For each individual, body mass index values (BMI) were calculated. The nutritional status was assessed by comparing the individual BMI with the age and sex specific standards set by the Ministry of Health of the Russian Federation (2017). Results and discussion. 74.4% of children aged 3-6 in KhMAO, and 70% of the 7-17-year-old children of KR and KhMAO meet the standards for their age-sex groups; 6.1% of children aged 3-17 are underweight and 19.5% are overweight. Among the 7-17-year-olds, the ratio of the underweight and overweight (including obese) differs significantly in the settlement dwellers of the KR from that in the living in small settlements of KhMAO (p=0.004), as well as in the group of town residents of KhMAO (p=0.017). The children of the KR have slightly higher percentage of the overweight and obese (26.6 vs 25.7 and 24.8% in the town and settlements of KhMAO, respectively), but significantly lower percentage of those who are underweight (1.9 vs 5.0 and 6.8%). The proportion of obese schoolchildren in small remote settlements of KhMAO is higher than that in the large settlements of KhMAO and in large settlements of the KR (13.1, 7.7 and 9.2%, respectively). Conclusion. There were no differences found between ethnic groups, however the role of social and anthropological factors in the formation of the nutritional status differences between the indigenous and non-indigenous children in Western Siberia calls for further investigation.

[Traditional nutrition and demography in the Arctic zone of Western Siberia].

High requirements for macro- and micronutrients of the organism of a pregnant woman living in the Far North are associated with the influence of extreme factors of high latitudes, and the needs of the mother and the growing fetus. Only the products of the unique food culture of the Arctic people - the Nenets, make it possible to meet the emerging needs. The aim of the work was to study the impact of traditional nutrition on the reproductive health of Nenets women living in the Arctic zone of Western Siberia. Material and methods. 619 indigenous inhabitants (Nenets) of the Yamal, Nadym and Taz districts of the Yamal-Nenets Autonomous Okrug at the age of 18-65 years were examined. The influence of the type of nutrition (traditional or imported products) on reproductive health indicators (the number of pregnancies, the number of children, the number of spontaneous abortions, frequency of gestosis, threats of termination of pregnancy, operative deliveries) for the period 2013-2018 was studied by analyzing official statistics and by questioning of the female population in own research. Results. The consumption of traditional products (venison, local fishery products, at least 3 times a week) by Nenets women was more often accompanied by a normal physiological course of pregnancy and childbirth (75.2 versus 64.2%, χ2=8.7; p=0.003). It led to a 1.5-fold decrease in the frequency of complications during pregnancy (gestosis, the threat of abortion) (χ2=5.8; p=0.01) and a 20% decrease in the frequency of delivery by cesarean section (χ2=16.6; p<0.001). As a result, a family whose diet was dominated by traditional products had a statistically significantly larger number of children (per child). Conclusion. The preservation of the consumption of reindeer and river fishery products by indigenous women will contribute to the sufficient intake of macro- and micronutrients, that will make it possible to gestate and give birth to a healthier generation of the Nenets society.

Access to radiotherapy among circumpolar Inuit populations.

Cancer is a substantial health burden for Inuit populations, an Indigenous peoples who primarily inhabit the circumpolar regions of Alaska, Canada, Greenland, and Russia. Access to radiotherapy is lacking or absent in many of these regions, despite it being an essential component of cancer treatment. This Review presents an overview of factors influencing radiotherapy delivery in each of the four circumpolar Inuit regions, which include population and geography, health-systems infrastructure, and cancer epidemiology. This Review also provides insight into the complex patient pathways needed to access radiotherapy, and on radiotherapy use. The unique challenges in delivering radiotherapy to circumpolar Inuit populations are discussed, which, notably, include geographical and cultural barriers. Recommendations include models of care that have successfully addressed these barriers, and highlight the need for increased collaboration between circumpolar referral centres in Alaska, Canada, Greenland, and Russia to ultimately allow for better delivery of cancer treatment.

Burden of disease from Helicobacter pylori infection in western Canadian Arctic communities.

BACKGROUND: Indigenous communities across the circumpolar north have elevated H. pylori (Hp) prevalence and stomach cancer incidence. We aimed to describe the Hp-associated disease burden among western Canadian Arctic participants in community-driven projects that address concerns about health risks from Hp infection. METHODS: During 2008-2013, participants underwent Hp screening by urea breath test and gastroscopy with gastric biopsies. We estimated Hp prevalence and prevalence by Hp status of endoscopic and histopathologic diagnoses. RESULTS: Among 878 participants with Hp status data, Hp prevalence was: 62% overall; 66% in 740 Indigenous participants; 22% in 77 non-Indigenous participants (61 participants did not disclose ethnicity); 45% at 0-14 years old, 69% at 15-34 years old, and 61% at 35-96 years old. Among 309 participants examined endoscopically, visible mucosal lesions were more frequent in the stomach than the duodenum: the gastric to duodenal ratio was 2 for inflammation, 8 for erosions, and 3 for ulcers. Pathological examination in 308 participants with gastric biopsies revealed normal gastric mucosa in 1 of 224 Hp-positive participants and 77% (65/84) of Hp-negative participants with sharp contrasts in the prevalence of abnormalities between Hp-positive and Hp-negative participants, respectively: moderate-severe active gastritis in 50 and 0%; moderate-severe chronic gastritis in 91 and 1%; atrophic gastritis in 43 and 0%; intestinal metaplasia in 17 and 5%. CONCLUSIONS: The observed pattern of disease is consistent with increased risk of stomach cancer and reflects substantial inequity in the Hp-associated disease burden in western Arctic Canadian hamlets relative to most North American settings. This research adds to evidence that demonstrates the need for interventions aimed at reducing health risks from Hp infection in Indigenous Arctic communities.

Sustained reductions of invasive infectious disease following general infant Haemophilus influenzae type b and pneumococcal vaccination in a Swedish Arctic region.

AIM: Vaccine-preventable pathogens causing severe childhood infections include Haemophilus influenzae type b (Hib), Streptococcus pneumoniae and Neisseria meningitidis. In this study conducted in a Swedish Arctic region, we evaluated the effects of general infant Hib and pneumococcal vaccination on invasive infectious diseases among children and assessed the need of meningococcal vaccination. METHODS: We identified cases of bacterial meningitis and sepsis from diagnosis and laboratory registers in the Västerbotten Region, Sweden, during 1986-2015. We then reviewed medical records to confirm the diagnosis and extract data for assessing incidence changes, using an exploratory data analysis and a time-series analysis. RESULTS: Invasive Haemophilus disease declined by 89.1% (p < 0.01), Haemophilus meningitis by 95.3% (p < 0.01) and all-cause bacterial meningitis by 82.3% (p < 0.01) in children aged 0 to four years following general infant Hib vaccination. Following pneumococcal vaccination, invasive pneumococcal disease declined by 84.7% (p < 0.01), pneumococcal meningitis by 67.5% (p = 0.16) and all-cause bacterial meningitis by 48.0% (p = 0.23). Incidence of invasive meningococcal disease remained low during the study period. CONCLUSION: Remarkable sustained long-term declines of invasive infectious diseases in younger children occurred following infant Hib and pneumococcal vaccinations in this Swedish Arctic region. Despite not offering general infant meningococcal vaccination, incidence of invasive meningococcal disease remained low.

Syndemic Factors Associated with Safer Sex Efficacy Among Northern and Indigenous Adolescents in Arctic Canada.

BACKGROUND: Syndemic approaches explore the synergistic relationships between social and health inequities. Such approaches are particularly salient for the Northwest Territories, Canada, that experiences national social (food insecurity, intimate partner violence [IPV]) and health (sexually transmitted infections [STI]) disparities. Safer sex efficacy (SSE) includes knowledge, intention, and relationship dynamics that facilitate safer sex negotiation. We examined factors associated with SSE among NWT adolescents. METHODS: We conducted a cross-sectional survey with a venue-based sample of adolescents aged 13-17 in 17 NWT communities from 2016 to 2017. Summary statistics and statistical comparisons were conducted, followed by crude and adjusted multivariable regression models to assess factors associated with SSE. RESULTS: Among participants (n = 610; mean age 14.2 years [SD 1.5]; 49.5% cisgender women, 48.9% cisgender men, 1.6% transgender persons; 73.3% Indigenous), one-quarter (n = 144; 23.6%) reported food insecurity and nearly one-fifth (n = 111; 18.2%) IPV. In adjusted analyses, among young women, food insecurity (ß - 1.89[CI - 2.98, - 0.80], p = 0.001) and IPV (ß - 1.31[CI - 2.53, - 0.09], p = 0.036) were associated with lower SSE, and currently dating was associated with increased SSE (ß 1.17[CI 0.15, 2.19], p = 0.024). Among young men, food insecurity (ß - 2.27[CI - 3.39, - 1.15], p = 0.014) was associated with reduced SSE. Among sexually active participants (n = 115), increased SSE was associated with consistent condom use among young women (ß 1.40[0.19, 2.61], p = 0.024) and men (ß 2.14[0.14, 4.14], p = 0.036). CONCLUSIONS: Food insecurity and IPV were associated with lower SSE-a protective factor associated with consistent condom use-underscoring the need to address poverty and violence to advance adolescent sexual health in the NWT.

Clostridium (Clostridioides) difficile shedding by polar bears (Ursus maritimus) in the Canadian Arctic.

Clostridium (Clostridioides) difficile has been identified in humans and a wide range of animal species, but there has been little study of remote animal populations with limited human contact. The objective of this study was to determine the prevalence and types of C. difficile in wild and captive polar bears (Ursus maritimus). Fecal samples were collected from two populations of wild polar bears in Nunavut Canada; M'Clintock Channel and Hudson Strait (Davis Strait or Foxe Basin), as well as from a facility (PBJ) in Churchill, Manitoba that temporarily houses nuisance polar bears and from captive bears in a zoological park. Enrichment culture was performed and isolates were characterized by ribotyping and toxinotyping. Clostridium difficile was isolated from 24/143 (16.8%) of samples; 18/120 (15%) wild bear samples, 4/7 (57%) from the PBJ and 2/16 (13%) samples from three zoo bears. The prevalence of C. difficile was significantly higher in bears that were housed at the PBJ vs wild bears (P = 0.0042), but there was no difference between wild bears from M'Clintock Channel (14/100, 14%) and those from Hudson Strait (4/20, 20%) (P = 0.50). Fourteen of the 24 (58%) isolates were toxigenic; 13/18 (72%) wild bear isolates, 0/4 PBJ isolate and 1/2 zoo isolates. Four toxigenic ribotypes were identified, with one that possessed tcdB and cdtA predominating. None of the toxigenic isolates were ribotypes that have been identified previously by the authors. There was no overlap in toxigenic ribotypes between the different populations. Clostridium difficile was not uncommonly identified in polar bears, with differences in type distribution amongst the different regions. The presence of strains that have not been identified in humans or domestic animals suggests that polar bears may be a natural reservoir of unique strains of this important bacterium.

Comparison of Helminth Infection among the Native Populations of the Arctic and Subarctic Areas in Western Siberia Throughout History: Parasitological Researches on Contemporary and the Archaeological Resources.

The aim of this parasitological study is examining contemporary (the late 20th century) specimens of the arctic or subarctic areas in Western Siberia and comparing them with the information acquired from archaeological samples from the same area. In the contemporary specimens, we observed the parasite eggs of 3 different species: Opisthochis felineus, Ascaris lumbricoides, and Enterobius vermicularis. Meanwhile, in archaeoparasitological results of Vesakoyakha, Kikki-Akki, and Nyamboyto I burial grounds, the eggs of Diphyllobothrium and Taenia spp. were found while no nematode (soil-transmitted) eggs were observed in the same samples. In this study, we concluded helminth infection pattern among the arctic and subarctic peoples of Western Siberia throughout history as follows: the raw fish-eating tradition did not undergo radical change in the area at least since the 18th century; and A. lumbricoides or E. vermicularis did not infect the inhabitants of this area before 20th century. With respect to the Western Siberia, we caught glimpse of the parasite infection pattern prevalent therein via investigations on contemporary and archaeoparasitological specimens.

The epidemiology of trichinellosis in the Arctic territories of a Far Eastern District of the Russian Federation.

Trichinellosis, a zoonotic disease caused by nematodes of the genus Trichinella, is still a public health concern in the Arctic. The aims of this study were to investigate the seroprevalence of anti-Trichinella IgG in aboriginal peoples of two settlements in the Chukotka Autonomous Okrug (Russian Federation) on the Arctic coast of the Bering Sea, and to evaluate the survival of Trichinella nativa larvae in local fermented and frozen meat products. A seroprevalence of 24.3% was detected in 259 people tested by an enzyme-linked immunosorbent assay (ELISA). The highest prevalence was detected among people who consumed traditional local foods made from the meat of marine mammals. Trichinella nativa larvae were found to survive for up to 24 months in a fermented and frozen marine mammal meat product called kopalkhen. Since the T. nativa life cycle can be completed in the absence of humans, it can be expected to persist in the environment and therefore remain a cause of morbidity in the human populations living in Arctic regions.

Vitamin D status and intake of lactating Inuit women living in the Canadian Arctic.

OBJECTIVE: To determine the prevalence and correlates of healthy vitamin D status in lactating Inuit women living in remote regions of the Arctic. DESIGN: Cross-sectional. SETTING: Households were selected randomly in thirty-six communities of Nunavut, Nunatsiavut and Inuvialuit Settlement Region. Dietary intake was assessed using a 24 h recall and an FFQ. Anthropometric measurements, household living conditions, supplement use and health status were assessed. In fasting samples, serum 25-hydroxyvitaimn D (25(OH)D) was measured using a chemiluminescent assay (LIAISON; Diasorin Inc.). SUBJECTS: Lactating Inuit women participating in the 2007-2008 International Polar Year Inuit Health Survey conducted in the months of August to October. RESULTS: Among participants (n 34), 8·8, 26·5 and 50·0 % had 25(OH)D concentrations at or above 75, 50 and 40 nmol/l, respectively. More than one-third of participants did not consume traditional foods during the previous day and only 11·3 % of total energy intake was derived from traditional foods. Only 14·7 % of the sample consumed the daily number of milk servings recommended by Canada's Food Guide (two servings) for First Nations, Inuit and Métis. Using multivariable logistic regression to examine 25(OH)D≥40 nmol/l, only higher body fat was inversely correlated with 25(OH)D concentration. CONCLUSIONS: The present study is the first to assess simultaneously vitamin D status and other known factors that affect it among lactating Inuit women living in remote communities in the Arctic. Healthy maternal vitamin D status was observed in 25 % of participants during the late summer and early autumn. This requires further assessment in a larger sample spanning more seasons.

Summary of available surveillance data on hepatitis C virus infection from eight Arctic countries, 2012 to 2014.

We summarised available hepatitis C virus (HCV) surveillance data for 2012-14 from Arctic/sub-Arctic countries/regions. We sent a HCV data collection template by email to public health authorities in all jurisdictions. Population statistics obtained from census sources for each country were used to estimate rates of reported acute and chronic/undifferentiated HCV cases. Seven countries with Arctic regions (Canada, Denmark, Finland, Greenland, Norway, Sweden and the United States, represented by the state of Alaska), including three Canadian territories and one province, as well as 11 Russian subnational Arctic regions, completed the data collection template. Data on acute HCV infection during 2014 was available from three Arctic countries and all Russian Arctic regions (rate range 0/100,000 population in Greenland, as well as Nenets and Chukotka Automous Okrugs (Russian subnational Arctic regions) to 3.7/100,000 in the Russian Republic of Komi). The rate of people with chronic/undifferentiated HCV infection in 2014 ranged from 0/100,000 in Greenland to 171.2/100,000 in Alaska. In most countries/regions, the majority of HCV-infected people were male and aged 19-64 years. Differences in surveillance methods preclude direct comparisons of HCV surveillance data between Arctic countries/regions. Our data can inform future efforts to develop standardised approaches to HCV surveillance in the Arctic countries/regions by identifying similarities/differences between the surveillance data collected.

Food insecurity and food consumption by season in households with children in an Arctic city: a cross-sectional study.

BACKGROUND: High rates of food insecurity are documented among Inuit households in Canada; however, data on food insecurity prevalence and seasonality for Inuit households with children are lacking, especially in city centres. This project: (1) compared food consumption patterns for households with and without children, (2) compared the prevalence of food insecurity for households with and without children, (3) compared food consumption patterns and food insecurity prevalence between seasons, and (4) identified factors associated with food insecurity in households with children in Iqaluit, Nunavut, Canada. METHODS: Randomly selected households were surveyed in Iqaluit in September 2012 and May 2013. Household food security status was determined using an adapted United States Department of Agriculture Household Food Security Survey Module. Univariable logistic regressions were used to examine unconditional associations between food security status and demographics, socioeconomics, frequency of food consumption, and method of food preparation in households with children by season. RESULTS: Households with children (n = 431) and without children (n = 468) participated in the survey. Food insecurity was identified in 32.9% (95% CI: 28.5-37.4%) of households with children; this was significantly higher than in households without children (23.2%, 95% CI: 19.4-27.1%). The prevalence of household food insecurity did not significantly differ by season. Demographic and socioeconomic characteristics of the person responsible for food preparation, including low formal education attainment (ORSept = 4.3, 95% CI: 2.3-8.0; ORMay = 3.2, 95% CI: 1.8-5.8), unemployment (ORSept = 1.1, 95% CI: 1.1-1.3; ORMay = 1.3, 95% CI: 1.1-1.5), and Inuit identity (ORSept = 8.9, 95% CI: 3.4-23.5; ORMay = 21.8, 95% CI: 6.6-72.4), were associated with increased odds of food insecurity in households with children. Fruit and vegetable consumption (ORSept = 0.4, 95% CI: 0.2-0.8; ORMay = 0.5, 95% CI: 0.2-0.9), as well as eating cooked (ORSept = 0.5, 95% CI: 0.3-1.0; ORMay = 0.5, 95% CI: 0.3-0.9) and raw (ORSept = 1.7, 95% CI: 0.9-3.0; ORMay = 1.8, 95% CI: 1.0-3.1) fish were associated with decreased odds of food insecurity among households with children, while eating frozen meat and/or fish (ORSept = 2.6, 95% CI: 1.4-5.0; ORMay = 2.0, 95% CI: 1.1-3.7) was associated with increased odds of food insecurity. CONCLUSIONS: Food insecurity is high among households with children in Iqaluit. Despite the partial subsistence livelihoods of many Inuit in the city, we found no seasonal differences in food security and food consumption for households with children. Interventions aiming to decrease food insecurity in these households should consider food consumption habits, and the reported demographic and socioeconomic determinants of food insecurity.

Neurovascular hand symptoms in relation to cold exposure in northern Sweden: a population-based study.

PURPOSE: To describe the self-reported ambient cold exposure in northern Sweden and to relate the level of cumulative cold exposure to the occurrence of sensory and vascular hand symptoms. We hypothesize that cold exposure is positively related to reporting such symptoms. METHODS: A questionnaire about cold exposure and related symptoms was sent out to 35,144 subjects aged 18-70 years and living in northern Sweden. RESULTS: A total of 12,627 out of 35,144 subjects returned the questionnaire (response rate 35.9%). Subjects living in the rural alpine areas reported more extensive cold exposure both during work and leisure time compared to the urbanized coastal regions. Frostbite in the hands was present in 11.4% of men and 7.1% of women, cold sensitivity was present in 9.7 and 14.4%, and Raynaud's phenomenon was present in 11.0% of men and 14.0% of women. There was a positive association between cumulative cold exposure and neurovascular hand symptoms. CONCLUSION: The present study demonstrates that the cold environment in northern Sweden might be an underestimated health risk. Our hypothesis that cold exposure is positively related to reporting of neurovascular hand symptoms was supported by our findings. In addition, such symptoms were common not only in conjunction with an overt cold injury. Our results warrant further study on pathophysiological mechanisms and suggest the need for confirmatory prevalence studies to support national public health planning.

Influenza A virus in the Western Arctic.

Small bays of bird bazaars of the Arctic Kola Peninsula (Barents Sea) have been studied. RNA of influenza A virus was found in the surface microlayer (SM) and aerosol samples from the bays located beneath bird colonies. The nucleotide sequencing of the PCR fragments from the SM and the sea aerosol showed their identity for each bay. Virus transfer mechanism along the "surface microlayer - sea aerosol" path has been proposed. The kinetic scheme of the virus-host-environment interaction, which allows the dependence of the viral population size on the temperature to be simulated, has been developed.

Epidemiology of Invasive Group A Streptococcal Disease in Alaska, 2001 to 2013.

The Arctic Investigations Program (AIP) began surveillance for invasive group A streptococcal (GAS) infections in Alaska in 2000 as part of the invasive bacterial diseases population-based laboratory surveillance program. Between 2001 and 2013, there were 516 cases of GAS infection reported, for an overall annual incidence of 5.8 cases per 100,000 persons with 56 deaths (case fatality rate, 10.7%). Of the 516 confirmed cases of invasive GAS infection, 422 (82%) had isolates available for laboratory analysis. All isolates were susceptible to penicillin, cefotaxime, and levofloxacin. Resistance to tetracycline, erythromycin, and clindamycin was seen in 11% (n = 8), 5.8% (n = 20), and 1.2% (n = 4) of the isolates, respectively. A total of 51 emm types were identified, of which emm1 (11.1%) was the most prevalent, followed by emm82 (8.8%), emm49 (7.8%), emm12 and emm3 (6.6% each), emm89 (6.2%), emm108 (5.5%), emm28 (4.7%), emm92 (4%), and emm41 (3.8%). The five most common emm types accounted for 41% of isolates. The emm types in the proposed 26-valent and 30-valent vaccines accounted for 56% and 78% of all cases, respectively. GAS remains an important cause of invasive bacterial disease in Alaska. Continued surveillance of GAS infections will help improve understanding of the epidemiology of invasive disease, with an impact on disease control, notification of outbreaks, and vaccine development.

Allergic disease and Staphylococcus aureus carriage in adolescents in the Arctic region of Norway.

BACKGROUND: Allergic diseases are common chronic diseases in children and adolescents, but limited epidemiological data are available during transition into adulthood. Nasal Staphylococcus aureus carriage has been linked to increased prevalence of allergic disease. The objective of this study was to define the prevalence of allergic diseases in adolescents above the Arctic Circle in Northern Norway and to study the associations of S. aureus carriage with allergic diseases. METHODS: A school-based cohort in late adolescence (18-19 years) was invited to participate in a cross-sectional study on lifestyle and health, and 868 attended (71.9%). Self-reported allergic disease and severity of eczema were assessed by Mechanisms of the Development of Allergy and Patient-Oriented Eczema Measure questionnaires. Participants were tested with spirometry and exhaled nitric oxide (FeNO) and swabbed for bacterial culture from nose and eczematous skin. RESULTS: We found asthma, eczema, allergic rhinitis (AR), and nasal S. aureus carriage among 11.9%, 10.4%, 26.0%, and 51.3% of the participants, respectively, and 10.2% had allergic multimorbidity. Lifetime prevalence for any allergic disease was 45.1%. Reduced lung function and increased FeNO were found in 11.6% and 22.1% in participants with asthma, respectively. Nasal S. aureus carriage was associated with eczema, severe asthma, and severe AR. FeNO > 25 ppb was associated with both asthma and nasal S. aureus carriage. CONCLUSION: Asthma, eczema, and AR are common among adolescents above the Arctic Circle in Norway. Allergic disease is associated with S. aureus carriage, but its role in the pathogenesis and severity is not established.

Injecting epidemiology into population viability analysis: avian cholera transmission dynamics at an arctic seabird colony.

Infectious diseases have the potential to spread rapidly and cause high mortality within populations of immunologically naïve hosts. The recent appearance of avian cholera, a highly virulent disease of birds caused by the bacterium Pasteurella multocida, at remote Arctic seabird colonies is an emerging conservation concern. Determining disease risk to population viability requires a quantitative understanding of transmission potential and the factors that regulate epidemic persistence. Estimates of the basic (R0 ) and real-time (Rt ) reproductive number are critical in this regard - enumerating the number of secondary infections caused by each primary infection in a newly invaded host population and the decline in transmission rate as susceptible individuals are removed via mortality or immunized recovery. Here, we use data collected at a closely monitored common eider (Somateria mollissima) breeding colony located in the Canadian Arctic to examine transmission and host population dynamics. Specifically, we infer epidemic curves from daily mortality observations and use a likelihood-based procedure to estimate changes in the reproductive number over a series of annual outbreaks. These data are interpreted in relation to concurrent changes in host numbers to assess local extinction risk. Consistent with expectations for a novel pathogen invasion, case incidence increased exponentially during the initial wave of exposure (R0  = 2·5; generation time = 6·5 days ± 1·1 SD). Disease conditions gradually abated, but only after several years of smouldering infection (Rt  ≈ 1). In total, 6194 eider deaths were recorded during outbreaks spanning eight consecutive breeding seasons. Breeding pair abundance declined by 56% from the pre-outbreak peak; however, a robust population of >4000 pairs remained intact upon epidemic fade-out. Overall, outbreak patterns were consistent with herd immunity acting as a mitigating factor governing in the extent and duration of mortality. Disease mortality is frequently modelled as a form of stochastic catastrophe in wildlife population assessments, whereas our approach gives shape to the functional response between transmission and host population dynamics. We conclude that increased emphasis on integrating epidemiological and population processes is essential to predicting the conservation impact of emerging infectious diseases in wildlife.

The diagnosis and treatment of Helicobacter pylori infection in Arctic regions with a high prevalence of infection: Expert Commentary.

Helicobacter pylori infection is a major cause of peptic ulcer and is also associated with chronic gastritis, mucosa-associated lymphoid tissue (MALT) lymphoma, and adenocarcinoma of the stomach. Guidelines have been developed in the United States and Europe (areas with low prevalence) for the diagnosis and management of this infection, including the recommendation to 'test and treat' those with dyspepsia. A group of international experts performed a targeted literature review and formulated an expert opinion for evidenced-based benefits and harms for screening and treatment of H. pylori in high-prevalence countries. They concluded that in Arctic countries where H. pylori prevalence exceeds 60%, treatment of persons with H. pylori infection should be limited only to instances where there is strong evidence of direct benefit in reduction of morbidity and mortality, associated peptic ulcer disease and MALT lymphoma and that the test-and-treat strategy may not be beneficial for those with dyspepsia.

Surveillance of infectious diseases in the Arctic.

OBJECTIVES: This study reviews how social and environmental issues affect health in Arctic populations and describes infectious disease surveillance in Arctic Nations with a special focus on the activities of the International Circumpolar Surveillance (ICS) project. METHODS: We reviewed the literature over the past 2 decades looking at Arctic living conditions and their effects on health and Arctic surveillance for infectious diseases. RESULTS: In regards to other regions worldwide, the Arctic climate and environment are extreme. Arctic and sub-Arctic populations live in markedly different social and physical environments compared to those of their more southern dwelling counterparts. A cold northern climate means people spending more time indoors, amplifying the effects of household crowding, smoking and inadequate ventilation on the person-to-person spread of infectious diseases. The spread of zoonotic infections north as the climate warms, emergence of antibiotic resistance among bacterial pathogens, the re-emergence of tuberculosis, the entrance of HIV into Arctic communities, the specter of pandemic influenza or the sudden emergence and introduction of new viral pathogens pose new challenges to residents, governments and public health authorities of all Arctic countries. ICS is a network of hospitals, public health agencies, and reference laboratories throughout the Arctic working together for the purposes of collecting, comparing and sharing of uniform laboratory and epidemiological data on infectious diseases of concern and assisting in the formulation of prevention and control strategies (Fig. 1). In addition, circumpolar infectious disease research workgroups and sentinel surveillance systems for bacterial and viral pathogens exist. CONCLUSIONS: The ICS system is a successful example of collaborative surveillance and research in an extreme environment.