Tuberculosis (TB) has occurred globally for centuries and remains a major public health problem. As in many other European countries, TB used to be endemic in Denmark, but during the past approximately 150 years, there has been a steep decline in the TB incidence. In 1978, Denmark became a low-incidence country for TB with less than 10 cases per 100,000 population per year. Over the years, great medical advances have been made such as the development and distribution of the Bacillus Calmette-Guérin (BCG) vaccine and the introduction of effective anti-tuberculous drugs. In Denmark, these advances have coincided with substantial economic growth and improved living conditions as well as the implementation of major public health interventions including mass TB screenings and the eradication of bovine TB [1]. Tuberculosis is now a rare disease prevailing mainly in specific risk groups in the society including migrants [2] and socially deprived residents [3,4]. However, the mortality among people with TB remains substantial [5].

Different factors have impacted the TB incidence and mortality over the past two centuries. In this article, we explore original TB data dating back to 1876, when it became mandatory to notify TB mortality in Danish towns [6]. In 1921, it became mandatory to notify all patients diagnosed with TB to a national registry [6]. These historical data provide a unique opportunity to describe the epidemiology of TB for an entire nation spanning nearly 150 years. It enables us to discuss the TB disease burden in Denmark ove