In tuberculosis (TB) low-incidence countries, TB is becoming increasingly concentrated in marginalised populations. Progress towards TB elimination therefore requires targeted interventions informed by knowledge on the determinants of disease in specific subpopulations. In Denmark, Greenlanders experience an exceptionally high TB incidence, approximately 170-fold higher than that of Danish-born individuals. Despite comprising only 0.3

Despite low TB incidence in Denmark, the disease disproportionately affects vulnerable groups. Implementation of screening, contact tracing, and preventive treatment remains fragmented. A national TB elimination plan, combining targeted outreach and social support, is needed to align with WHO goals and move toward elimination by 2050, as argued in this review.

AIM:Tuberculosis (TB) among refugee minors in low-incidence countries remains underexplored. We estimated the incidence of TB disease among refugee minors compared to Danish-born minors. METHODS:This nationwide prospective historical cohort study included 31 172 refugee minors (< 18 years) granted residency in Denmark from 1993 to 2015. Each was matched 1:6 with a Danish-born control on age and sex. Follow-up extended from the date of residency until the earliest of: TB diagnosis, the age of 21 years, or study-end (31.12.2015). Data were obtained from Statistics Denmark and the International Reference Laboratory of Mycobacteriology. We conducted descriptive analyses and estimated incidence rates (IRs) using Poisson regression. RESULTS:Refugee minors had a 48 times higher TB IR compared to their Danish-born peers. Notably, refugee minors from sub-Saharan Africa had an IR of 203 per 100 000 person-years. For both refugee minors and their Danish-born peers, pulmonary TB was the most common form, but still more than a third had extrapulmonary manifestations. Among refugee minors, most TB cases were diagnosed more than 2 years after arrival. CONCLUSION:Our findings underscore the need for national policies and clinical guidelines for TB screening of all refugee minors upon arrival to reduce morbidity and advance TB elimination efforts.

BACKGROUND:The extent and burden of post-acute cognitive dysfunctions following SARS-CoV-2 infection is uncertain. METHODS:25,485 SARS-CoV-2 test-positive and 25,032 test-negative individuals were repeatedly asked to score symptoms of subjective cognitive deficits 2 to 18 months after test using the "Cognitive complaints in bipolar disorder rating assessment" (COBRA) tool. Poisson mixed-effects models were used to estimate Score Ratios (SRs) by comparing scores between test-positive and test-negative individuals. RESULTS:At each follow-up point, test-positive individuals have low but slightly higher mean COBRA scores compared with test-negatives. For the combined 2-18 months period, COBRA scores among test-positive individuals are 11% higher than corresponding scores among test-negatives (SR2-18mth = 1.11 (95% CI; 1.09-1.13)). Of effect modifiers explored, being hospitalized with a positive SARS-CoV-2 test particularly elevates COBRA scores (SR2-18mth = 1.38 (95% CI; 1.24-1.54)). CONCLUSION:In the general population of SARS-CoV-2 infected individuals, self-reported post-acute scores of cognitive dysfunctions are low and only slightly higher than corresponding scores among test-negatives. Higher COBRA scores among hospitalized SARS-CoV-2 test positives corroborate with long-term cognitive impairment being most pronounced among those with severe SARS-CoV-2 infection.

BACKGROUND:Following the introduction of direct-acting antivirals (DAAs), elimination of hepatitis C virus (HCV) became a target of the World Health Organisation (WHO) in 2016. Denmark had a HCV prevalence of 0.21% in 2016, and in 2018, unrestricted access to DAAs was introduced together with intensified testing strategies. AIM:To estimate adult HCV diagnostic and treatment coverage in Denmark by the end of 2022. METHODS:Four national HCV source registers (laboratory reports, surveillance notifications, treatment database and hospital diagnoses) were merged. Capture-recapture analysis was used to estimate diagnosed individuals not identified in the registers, and estimates were adjusted for treated patients. The undiagnosed population was estimated using HCV testing data among high-risk individuals recorded in the Register for Treatment of Drug Use and compared with Danish studies on the diagnosed fraction of newly detected HCV cases. RESULTS:Across the four registers, 1,649 valid records of HCV-infected adults alive and resident in Denmark were identified. Capture-recapture analysis estimated a total of 1,700 (95% CI: 1,677-1,739) diagnosed individuals. With an undiagnosed fraction of 22-32%, the total HCV-infected population was estimated at 2,471-2,582 individuals, corresponding to a prevalence of 0.05-0.06% by the end of 2022. Compared to the 2016 baseline 82% had been diagnosed and 77% of diagnosed patients had been treated for HCV. CONCLUSION:HCV prevalence in Denmark has declined substantially, and with ongoing national initiatives to test and treat the remaining HCV patients we are likely to achieve WHO targets of diagnostic coverage and treatment before 2030.

This proceedings paper summarizes the first network meeting in the project Strengthening Networks in Arctic Health Research and Education through Mentorship and Collaboration, held in Copenhagen, Denmark, from 26-28 May 2024. The meeting brought together 31 participants from across the Arctic, including Indigenous and non-Indigenous researchers, students, and health professionals. The aim was to enhance collaboration among circumpolar health networks and to develop a mentorship program supporting young scholars. Sessions included mapping exercises, regional health updates, and discussions on ethics, education, collaboration, and community engagement. Participants identified overlapping mandates, gaps in coordination, and opportunities for joint initiatives across different health networks and societies. The meeting emphasized inclusive, community-based approaches and the integration of Indigenous knowledge. Action items for the coming years include developing and evaluating a model for mentorship in circumpolar health research, enhancing ethical research practices, and continuing the work and conversation of coordinating efforts across health networks. The workshop was concluded with a strong sense of shared purpose and commitment to advancing health and well-being in Arctic communities through strengthened collaborative in both research and education.

Background:Climate change may alter zoonotic disease patterns in the Arctic, yet knowledge remains limited. Design:Antibodies to seven zoonotic pathogens were analyzed in 660 unselected human sera drawn from serum banks from Greenland (n = 460) and Northern Sweden (n = 200) (1998-2017), frequency-matched with respect to sex, age, ethnicity and place of living. Greenlandic samples were tested for Francisella tularensis, Brucella melitensis, Brucella abortus, Coxiella burnetii, Rickettsia spp., and Leptospira spp., while Swedish samples also included Borrelia burgdorferi sensu lato (Bbsl) and tick-borne encephalitis virus (TBEV). Results:Leptospira seroprevalence was higher in Greenland 2013 (18 %, 95 % CI 13-24 %) than in Sweden 2012-2017 (4 %, 95 % CI 2-8 %) and increased significantly over time in West Greenland (1998: 2.5 %, 95 % CI 0.8-6 %; 2013: 30 %, 95 % CI 18-45 %, p < 0.001, OR 16.7, 95 % CI 5.7-48.9). Rickettsia seroprevalence remained stable over time (12 %, 95 % CI 5-24 %). Seroprevalence of F. tularensis and B. melitensis/abortus in Greenland 2013 was less than 1 %. In Sweden, seroprevalence was 1 % (95 % CI 0.1-4 %) for B. melitensis/abortus, 2 % (95 % CI 0.1-5 %) for Bbsl, 3 % (95 % CI 1-6 %) for F. tularensis, and 5 % (95 % CI 2-9 %) for TBEV. Antibodies to C. burnetii were not detected in any sample. Two of 81 polar bear samples from East Greenland (2016-2023) were seropositive for Leptospira spp. Conclusions:This first report on human Leptospira infection in Greenland highlights rising seroprevalence, possibly linked to contaminated water and global warming. Findings emphasize widespread Rickettsia exposure in northern regions and tick-borne pathogens in Sweden, underscoring the need for updated public health data to inform public health planning.

INTRODUCTION:Correct use of tuberculosis (TB) diagnosis codes is essential for patient care, surveillance and resource allocation. We aimed to assess the positive predictive value (PPV) of TB diagnosis codes. METHODS:In this retrospective cohort study, we identified patients with International Classification of Diseases, tenth version (ICD-10) TB diagnosis codes from 1 July 2020 to 30 June 2023, at two TB centres in the Central Denmark Region. Confirmed TB was defined as microbiologically confirmed TB, prescription of ≥ 3 first- or second-line TB drugs, or TB notification. All patients who did not meet these criteria and those who received fewer than three TB drugs or lacked TB notification underwent manual hospital record review to verify or exclude the TB diagnosis. PPVs were calculated as the proportion of confirmed TB diagnoses among all patients with a TB diagnosis code. RESULTS:In total, 185/230 patients were confirmed to have TB, yielding a PPV of 80% (95% CI: 75; 85). The PPVs for TB microbiology, TB prescriptions and TB notification exceeded 95% individually. Excluding TB lupus codes increased the PPV to 89% (95% CI: 84; 93). Patients with more than one different type of TB diagnosis code had a PPV of 100% (95% CI: 93; 100). Additionally, PPVs were high when TB diagnosis codes appeared on multiple occasions, increasing with the number of occurrences (≥ 2: 85%, ≥ 3: 89%, ≥ 4: 93%). CONCLUSION:TB ICD-10 diagnosis codes demonstrate a moderately high PPV in Denmark, particularly when excluding TB lupus codes, highlighting the importance and complexities of diagnostic coding. FUNDING:None. TRIAL REGISTRATION:Not relevant.

BACKGROUND:Few studies have addressed the burden of neurological disorders in Greenland (GL). We aim to estimate nationwide incidences and prevalence of a broad group of neurological disorders in the total Greenlandic population and according to ethnicity (Inuit, Non-Inuit). To explore the importance of ethnic and environmental factors we estimated corresponding rates among Inuit and Non-Inuit living in Denmark (DK). METHODS:A long-standing collaboration between the Danish and Greenlandic healthcare system enabled us to follow the Greenlandic and Danish population for dementia, Parkinson's Disease (PD), epilepsy, stroke, and infections of the Central Nervous System using national registries from both countries. Incidence rates (IRs) were calculated using log linear Poisson-regression for the combined period 1987-2014, and stratified according to ethnicity, country of residence and periods. Age-standardized IRs (ASIRs) were based on the WHO 2000-2025 standard population. RESULTS:The Greenlandic IRs of epilepsy and ischemic stroke were 98.6 (95% CI: 93.8-104) and 118 (95% CI: 113-124) respectively, per 100,000 person-years of risk. IRs for the remaining neurological disorders were below 40 per 100,000. During follow-up we observed an increase in IRs of ischemic stroke and a less pronounced for dementia. Apart from dementia, ASIRs of neurological disorders were generally higher in the Greenlandic population compared with the Danish, most pronounced for subarachnoid hemorrhage (ASIRGL/ASIRDK = 2.36 (2.12-2.62)). Inuit in Greenland were at a lower risk of stroke, PD and especially dementia (ASIRGL/ASIRDK = 0.40 (0.35-0.46)) compared with Inuit in Denmark. The most prevalent neurological disorders in Greenland in 2014 were stroke and epilepsy. CONCLUSION:Our study emphasizes that stroke and epilepsy are important causes of morbidity in Greenland and suggests that dementia may become a challenge. Noticeable differences according to ethnicity and country of residence warrants further research.

In low TB incidence countries, prevention and care activities addressing migrant populations are essential for TB control. Understanding characteristics of TB patients in the migrant population is important for planning and providing appropriate care. This study aims to inform prevention and care strategies by describing characteristics of TB patients within migrant subpopulations in Europe to understand whether differences exist in their patient profiles. This cross-sectional descriptive study of migrants with TB reported to the European Surveillance System (2014–2020) from 23 low incidence European countries describes characteristics of different subgroups, according to TB epidemiological indicators and interval between arrival and notification. Migrants with TB originating from very high TB incidence countries had the highest proportion of people living with HIV (7

BackgroundAs tuberculosis (TB) incidence rates decrease faster in native than migrant populations in European countries, addressing migrant health becomes increasingly important in TB programmes.AimTo inform European TB prevention and control policies, we analysed data on TB in migrants in low TB-incidence European countries (TB incidence < 10/100,000 population) during 2014-2020 by migrant origin, destination, and recent vs non-recent immigration.MethodsData on migrant TB patients were derived from the European Surveillance System (TESSy) and data on migrant populations from Eurostat or national statistical offices. We calculated annual migrant TB crude incidence rates (CIRs) per country of origin, destination country and year, for all migrants with TB and recently arrived migrants with TB, the latter defined by TB diagnosis within 1 year after arrival in the destination country.ResultsIn 2014-2020, 104,371 migrants with TB were reported to TESSy by 20 destination countries. Average annual migrant CIRs were highest in the United Kingdom (43/100,000). Origin countries of most migrant TB patients were India (n = 9,561), Romania (n = 8,345), and Pakistan (n = 7,300). The highest CIRs were found among migrants from Eritrea (480/100,000), Somalia (414/100,000) and The Gambia (343/100,000), and were higher than estimated World Health Organization incidences for those countries. The CIRs among recently arrived migrants appeared higher than in the overall migrant population.ConclusionsWe found substantially higher CIRs in certain migrant subpopulations than others. TB rates in recent migrants appeared to be up to 11 times higher than in corresponding origin countries. Tailored and regularly adapted TB prevention and control strategies are needed.

BACKGROUND:Hand eczema (HE) is described as a common disease in Greenland, but studies on its epidemiology and severity are lacking. OBJECTIVES:To investigate the point prevalence and severity of HE among adults in East Greenland in relation to age, sex, and occupation. METHODS:In May 2022, we conducted a cross-sectional study in Tasiilaq, East Greenland. All adults aged ≥ 18 years were invited (n = 1311 individuals). RESULTS:A total of 295 participants accepted the invitation. Among these, the point prevalence of HE was 22.4% (95% confidence interval [CI]: 18.0-27.5, n = 66/295), and 5.0% based on the total invited population (n = 66/1311). The median age of participants with HE was 40 years (interquartile range [IQR]: 30-54), and the median age at disease onset was 25 years ([IQR]: 19-40). Females were more frequently affected than males (65.2%, n = 43/66). Atopic dermatitis was diagnosed in 7.6% of participants with HE. The mean Hand Eczema Severity Index (HECSI) score was 21 (range 2-112), and exposure to wet work was reported by 57.4% of the participants with HE. CONCLUSIONS:Hand eczema is common in East Greenland, with a point prevalence similar to that in Nordic countries. The severity and distribution of HE in relation to age, sex, and occupation were comparable to those reported in other European studies.

BackgroundDuring the early part of the COVID-19 pandemic, travel restrictions were implemented in Greenland to contain SARS-CoV-2 transmission. Despite their widespread use, empirical evidence supporting the effectiveness of travel restrictions is scarce. Greenland was in a unique position to maintain pre-departure testing among travellers, and we aimed to describe the effectiveness of pre-departure testing to inform the implementation of travel restrictions in future outbreaks.MethodsOur analysis included SARS-Cov-2 PCR test results from travellers, including children, arriving in Greenland from Denmark between June 15, 2020, and January 26, 2022. Additionally, we identified positive tests performed within 14 days post-arrival to Greenland in this population. We estimated the sensitivity of pre-departure screening by dividing the number of positive cases identified pre-departure by the sum of cases identified pre-departure and within 14 days post-arrival in Greenland.ResultsOur analysis covered around 43% of all travellers who underwent pre-departure screening. Out of 26,406 SARS-CoV-2 PCR tests, the proportion of positive tests was 0.6%, which varied over time according to the incidence in Denmark. Overall sensitivity of pre-departure screening was 59% and decreased over time, reaching a minimum of 36% in January 2022. The overall proportion of positive PCR post-arrival tests among all travellers was 0.4%.ConclusionsImplementing pre-departure PCR testing for SARS-CoV-2 among travellers can be effective in the early stages of outbreaks, particularly in geographical regions like Greenland where community transmission had not yet occurred. Our findings suggest that pre-departure screening of travellers contributed to delaying community transmission in Greenland compared to most other countries, thereby reducing the COVID-19 disease burden.

Objectives: The study aimed to investigate the association between quantitative T-SPOT.TB values and the risk of incident and prevalent tuberculosis disease (TBD), identify risk factors, and evaluate test accuracy. Methods: This retrospective cohort study followed patients tested consecutively with T-SPOT.TB at Aarhus University Hospital from 2010 to 2017, with follow-up for incident TBD through 2022. Data on demographics, comorbidities, medications, and TB status were collected from patient records and national registries. Cox proportional hazard models with restricted cubic splines assessed the risk of incident TBD (occurring >= 3 months post-test) by quantitative spot counts. Cox and log-binomial regressions identified risk factors for incident and prevalent TBD (occurring between 3 months before and after the test). Sensitivity, specificity, and predictive values assessed test accuracy. T-SPOT.TB was the index test, and microbiologically and/or clinically confirmed TBD was the reference standard. Results: Among 8542 individuals with complete follow-up, 59 developed incident TBD over 67 456 person-years. Among 9014 individuals tested once, 162 had prevalent TBD at the time of testing. The risk of incident TBD increased with higher spot counts, plateauing for tests with more than ten spots. The strongest risk factors for both incident and prevalent TBD were categorical T-SPOT.TB results: compared with negative tests (c4 spots), adjusted hazard ratios for incident TBD were 5.0 (95% CI: 1.9-13.1) for borderline (5-7 spots) and 8.0 (95% CI: 4.0-15.7) for positive tests (>= 8 spots). Adjusted risk ratios for prevalent TBD were 14.9 (95% CI: 7.7-28.9) for borderline and 35.6 (95% CI: 21.4-59.2) for positive tests. Sensitivities for incident and prevalent TBD were 54.0% (95% CI: 39.3-68.2%) and 78.4% (95% CI: 71.3 -84.5%), respectively. Specificities were 84.8 (84.0-85.4) and 83.7 (82.9-84.4), respectively. Discussion: Incident TBD risk increases with T-SPOT.TB values but plateaus beyond 10 spots. Borderline and positive T-SPOT.TB results are strongly linked to TBD risk. Ole Skouvig Pedersen, Clin Microbiol Infect 2025;31:808 (c) 2025 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

BackgroundMany countries reported declines in acute respiratory infections (ARIs) following public health and social measures to mitigate COVID-19.ObjectivesWe describe the potential association with pandemic restrictions on the occurrence of non-COVID ARIs in Greenland, which experienced a late but sudden introduction of COVID-19.MethodsWe included national electronic medical records on ARIs in Greenland across three periods: pre-pandemic (January 2018-February 2020), pandemic (March 2020-June 2022), and endemic (July 2022-December 2023). Severe ARIs were defined using a case definition based on ICD-10/ICPC-2-R codes. Oral penicillin prescriptions served as a proxy for mild ARIs due to limited primary care data.We calculated ARI incidence and used Poisson regression to compare periods. Data on Influenza A/B and RSV PCR testing activity and results were included.ResultsDuring the pandemic, all ARIs decreased by 14% (IRR 0.86 [95% CI 0.84-0.88]) compared to pre-pandemic levels. In the endemic period, mild ARIs increased by 3% (IRR 1.03 [95% CI 1.02-1.06]), while severe ARIs increased by 40% (IRR 1.40 [95% CI 1.22-1.60]). The Influenza A/B positive rate declined during the pandemic (20.7% to 8.3%) but increased in the endemic period (14.2%), whereas RSV positive rate increased during the pandemic (19.8% to 57.2%).ConclusionsWe observed declines in mild and severe ARIs during the pandemic in Greenland. Unlike many other countries, mild ARIs did not rise during the endemic period, likely due to preventive travel measures limiting the spread of SARS-CoV-2 while allowing ongoing exposure to other respiratory viruses in society, preventing an infection rebound.

[This corrects the article DOI: 10.1371/journal.pone.0275518.].

BACKGROUND:Many Greenlanders move from Greenland, a tuberculosis (TB) high-incidence country, to Denmark, a TB low-incidence country. Surprisingly, according to official statistics, the TB incidence among Greenlanders in Denmark is much higher than in Greenland. OBJECTIVES:This study investigates factors contributing to the extraordinarily high TB incidence among Greenlanders residing in Denmark. METHODS:Retrospective, register-based cohort study including all Greenlanders ≥18 years notified with TB in Denmark and Greenland, and Danes ≥18 years with TB in Denmark, 2006-2022. Demographic and microbiological characteristics were compared across groups using parametric and non-parametric statistical tests. RESULTS:The TB incidence was extraordinarily high among Greenlanders in Denmark (341/100,000; n = 813), compared to Danes in Denmark (2/100,000; n = 1799) and Greenlanders in Greenland (149/100,000; n = 1088). Additionally, they were more often part of a TB cluster (75.6%) compared to Danes in Denmark (53.3%) and Greenlanders in Greenland (64.0%) and demonstrated very high rates of recurrent TB (23.9%), with 75.6% of cases being reinfections involving new Mycobacterium tuberculosis strains. CONCLUSION:TB poses a significant public health challenge for Greenlanders in Denmark. Their high incidence combined with elevated clustering and reinfection rates suggest substantial active TB transmission, and their cluster distribution indicates that many infections are locally acquired rather than reactivations of infection acquired in Greenland. Greenlanders with TB in Denmark are likely part of a socially marginalised minority with TB high-risk behaviours similar to Danes developing TB. These findings highlight the need for targeted TB prevention and control strategies for Greenlanders residing in Denmark.

Few studies on epilepsy in Greenlandic children exist, and the results are inconsistent. The objective of this study was to estimate the burden of epilepsy in children in Greenland and Denmark and secondly to identify demographic risk factors. Third, the risk of epilepsy after febrile seizures should be estimated. A register-based cohort study of all children in Greenland and Denmark aged 0-15 years from 1987 to 2014 was conducted. Using the Greenlandic and Danish National Patient Register, cases were identified and coupled to demographics through the Civil Registration System. The outcomes were incidence rates (IR) per 100,000 person-years (PY) and hazard ratios (HR).The study showed an epilepsy IR of 150/100,000 PY (139-162) in Greenland and 110/100,000PY (108-111) in Denmark and an HR of 1.34. The IRs were very high in the first years of life. A significantly higher HR was found for male sex, Inuit ethnicity in Greenland and habitation in Greenland outside of the capital. The risk of epilepsy after the diagnosis of febrile seizures was almost doubled in Greenland compared with Denmark.

BACKGROUND:The Global Burden of Disease Group modelled a surprisingly high prevalence of Multiple Sclerosis (MS) in the Greenlandic population in 2016 of 290 per 100,000, higher than that in Denmark, a high-risk country of MS. OBJECTIVE:Obtain accurate data on the burden (prevalence and incidence rates) of MS in Greenland, 1973 - 2014, overall and according to ethnicity. METHODS:Greenlandic prevalence and incidence rates were estimated using validated data from the Danish Multiple Sclerosis Registry (Greenlandic citizens suspected of MS were until 2014 supposed to be transferred to Denmark). The relative risk of MS in the Greenlandic population versus that in the Danish was estimated as the ratio of observed to expected numbers of MS according to Danish national sex-, age- and period-specific MS incidence rates, i.e. Standardized Incidence Ratio (SIR). RESULTS:In 2014, seven persons were living with MS in Greenland (prevalence=12.52 per 100,000) and 22 new MS cases were registered from 1973 to 2014 (incidence rate=0.97 (95 % CI; 0.64-1.47) per 100,000 person-years of risk). Inuit and Non-Inuit in Greenland, and Inuit in Denmark had MS risks of 2 % (SIR=0.02 (0.01-0.06)), 67 % (SIR=0.67 (0.42-1.04)) and 23 % (SIR=0.23 (0.13-0.39)) respectively, of that in the Danish Non-Inuit population. To enhance completeness, possibly at the risk of misclassification we included MS diagnoses from the Greenlandic and Danish National Patient registries. In 2014, prevalence of MS in Greenland was now 48.29 per 100,000. CONCLUSION:Our study does not support prior claims of Greenland being a high MS risk country. MS is still relatively rare among Inuit living in Greenland.