Ten years of tuberculosis intervention in Greenland – has it prevented cases of childhood tuberculosis?

Background: The incidence of tuberculosis (TB) disease in Greenland doubled in the 1990s. To combat the increase, national TB interventions were initiated in 2000 and strengthened in 2007. Objective: To determine whether the effect of interventions could be detected, we estimated the TB disease risk among children≤15 years before and after interventions were implemented. Design: For a study cohort, we recruited all children ≤15 years of age included in the Greenlandic Civil Registration System (CRS) from 1990 to 2010. The CRS identifier was used to link cohort participants with TB cases identified based on the Greenlandic National TB registry. Bacille Calmette Guerin (BCG) vaccination status was identified through year of birth, as BCG was offered to newborns born either before 1991 or after 1996. Years with interventions were defined as 2000–2006 (primary interventions) and 2007–2010 (intensified interventions). Risk of TB was estimated using Poisson regression. Results: The study included 35,858 children, of whom 209 had TB disease. The TB disease incidence decreased after interventions were implemented (2007–2010: IRR [incidence rate ratios] 0.62, 95% CI: 0.39–0.95, p=0.03, compared with the 1995–1999 period). The TB disease risk was inversely associated with BCG vaccination (IRR: 0.54, 95% CI: 0.41–0.72, p<0.001). Conclusions: Years with national TB interventions in Greenland, including neonate BCG vaccination, are associated with a lower TB disease incidence among children ≤15 years of age

CNS infections in Greenland: A nationwide register-based cohort study

<div><p>Background</p><p>Indigenous Arctic people suffer from high rates of infectious diseases. However, the burden of central nervous system (CNS) infections is poorly documented. This study aimed to estimate incidence rates and mortality of CNS infections among Inuits and non-Inuits in Greenland and in Denmark.</p><p>Methods</p><p>We conducted a nationwide cohort study using the populations of Greenland and Denmark 1990–2012. Information on CNS infection hospitalizations and pathogens was retrieved from national registries and laboratories. Incidence rates were estimated as cases per 100,000 person-years. Incidence rate ratios were calculated using log-linear Poisson-regression. Mortality was estimated using Kaplan-Meier curves and Log Rank test.</p><p>Results</p><p>The incidence rate of CNS infections was twice as high in Greenland (35.6 per 100,000 person years) as in Denmark (17.7 per 100,000 person years), but equally high among Inuits in Greenland and Denmark (38.2 and 35.4, respectively). Mortality from CNS infections was 2 fold higher among Inuits (10.5%) than among non-Inuits (4.8%) with a fivefold higher case fatality rate in Inuit toddlers.</p><p>Conclusion</p><p>Overall, Inuits living in Greenland and Denmark suffer from twice the rate of CNS infections compared with non-Inuits, and Inuit toddlers carried the highest risk of mortality. Further studies regarding risk factors such as genetic susceptibility, life style and socioeconomic factors are warranted.</p></div

Incidence rate (IR) per 100,000 person years of CNS infections in Greenland and Denmark, 1990–2012.

<p>Incidence rate (IR) per 100,000 person years of CNS infections in Greenland and Denmark, 1990–2012.</p

Incidence rate of laboratory-confirmed bacterial meningitis and the distribution of bacterial agents in meningitis cases in Greenland 1990–2012 and in Denmark 2011–2012 identified by culture in either cerebrospinal fluid (CSF) or blood.

<p>Incidence rate of laboratory-confirmed bacterial meningitis and the distribution of bacterial agents in meningitis cases in Greenland 1990–2012 and in Denmark 2011–2012 identified by culture in either cerebrospinal fluid (CSF) or blood.</p

Incidence rate of CNS infection by age, ethnicity and country in Greenland and Denmark, 1990–2012.

<p>Incidence rate of CNS infection by age, ethnicity and country in Greenland and Denmark, 1990–2012.</p

Seven days mortality from CNS infections by age, ethnicity and country in Greenland and Denmark, 1990–2012.

<p>Seven days mortality from CNS infections by age, ethnicity and country in Greenland and Denmark, 1990–2012.</p