Report on the Epidemiology of Tuberculosis in Germany - 2018

full report in German

In 2018, a total of 5,429 tuberculosis (TB) cases were notifi ed in Germany. This corresponds to an annual TB incidence of 6.5 cases per 100,000 population. Thus, after the signifi cant increase in case numbers in 2015 and the almost unchanged situation in 2016, case numbers are now declining again, but remain at a comparatively high level.

Analysis of demographic data: Tuberculosis incidence was 8.9 cases per 100,000 population in men and 4.3 in women (male to female ratio of 2.1). The age-specifi c incidence was highest in the age group 20-24 years (18.4 cases per 100,000 population; 24.7 in men and 11.3 in women).

Citizenship: Tuberculosis incidence in foreign nationals residing in Germany was almost 18 times higher than the incidence in German citizens (37.3 vs. 2.1 cases per 100,000 population, respectively), with the largest diff erence being observed in young adults. Overall, Germans comprised of 30.2% of all tuberculosis cases, whereas the remaining 69.8% of all cases were foreign nationals. Foreign nationals aff ected by tuberculosis were younger than German nationals (median age: 28 vs. 59 years).

The analysis by country of birth showed that the proportion of foreign-born patients – as in the previous two years – accounted for almost three-quarters of all patients. The most frequently registered foreign countries of birth in 2018 were Eritrea and Somalia, as also in the previous year.

Tuberculosis in children: A total of 215 cases were reported in children younger than 15 years of age (incidence 1.9 cases per 100,000 children), corresponding to a slight decrease of 25 cases in comparison to 2017 (240 cases; incidence 2.1 per 100,000 children). The majority of these cases had a direct or indirect (through parents) foreign background. Tuberculosis incidence was highest in the youngest age group of below fi ve years of age (113 cases; incidence 2.9 per 100,000). In children aged 5 to 9 years, the incidence of TB was 1.2 per 100,000 (43 cases), while in children aged 10 to 14 years, it was 1.6 per 100,000 (59 cases). Tuberculosis incidence among children of foreign nationality was almost 14 times higher in comparison to children with German nationality (10.6 vs. 0.8 per 100,000 population).

Case fi nding: In 2018, 3,928 (82.7%) of all tuberculosis cases were detected through passive case finding, of which 13 cases (0.3%) were detected through post-mortem examination. The number of tuberculosis cases detected by active case fi nding was 823 (17.3%) – in particular due to contact tracing (7.5%, 358 cases) and the legally mandated screening of asylum seekers and refugees (7.4%, 351 cases).

Site of disease: Pulmonary tuberculosis was diagnosed in 72.9% of all cases (3,916 cases; incidence 4.7 per 100,000) and was potentially infectious (sputum-smear or culture positive) in the majority of cases (3,193 cases, incidence 3.9). Of the pulmonary TB cases, 45.5% (1,780 cases) were smear-positive and, thus, were the most infectious cases. Extra-pulmonary tuberculosis exclusively, with no pulmonary manifestation, was diagnosed in 1,454 cases (27.1%), among which the lymph node was the main aff ected site in almost half the cases (761 cases; 52.3%).

Drug-resistant tuberculosis: The proportion of multidrug-resistant tuberculosis (MDR-TB) cases was 3.1% (118 cases) in 2018, and, therefore, remained almost unchanged in comparison to 2017 (3.1%, 122 cases).

The proportion of MDR-TB was highest in patients born in one of the newly independent states (NIS) of the former Soviet Union (21.2% compared to 1.1% in German-born patients). Among MDRTB cases with available information, 48.3% had additional resistances to second-line anti-tuberculosis drugs in 2018, of which eight cases had extensively drug-resistant tuberculosis (XDR-TB). The overall proportion of tuberculosis cases resistant to at least one of the fi ve standard anti-tuberculosis drugs (isoniazid, rifampicin, ethambutol, pyrazinamide, and streptomycin) was 13.0% in 2018, which was slightly higher than in 2017 (12.0%). The proportion of any drug-resistant TB cases was considerably higher among patients born in an NIS country in comparison to those born in Germany (35.5% vs. 9.2%, respectively).

Deaths: A total of 129 patients died of tuberculosis in 2018, including one child aged 12 years. This corresponded to a mortality rate of 0.2 cases per 100,000 population. The case fatality rate was 2.4%, which was slightly higher than in the previous year (2017: 2.1%, 114 deaths).

Treatment outcome can only be assessed after at least 12 months of follow-up and is, therefore, reported here for cases notifi ed in 2017. The completeness of treatment outcome reporting was 86.8% (4,770 of 5,495 reported cases). Among patients with available information, 80.3% (3,829 cases) were treated successfully, 11.3% (539 cases) experienced an unsuccessful treatment outcome for diff erent reasons, 3.8% (182 cases) were still on treatment, and 4.6% (220 cases) were reported as having transferred out. Successful treatment outcome showed age-specifi c diff erences, with a higher proportion (> 85%) of treatment success reported for children and young adults. This proportion declined in older age groups, reaching a successful treatment completion rate of only 49.8% among patients aged 80 years or older.

Conclusion: Detailed analysis of notifi cation data shows that the tuberculosis situation in Germany is mainly infl uenced by migratory movements and demographic changes in the population. Following the signifi cant increase in notifi ed tuberculosis cases in 2015 and almost identical case numbers in 2016, a slight decline in case numbers was observed in 2017 and 2018.

The previous increase in case numbers can be directly attributed to the legally mandated active case fi nding among refugees and asylum seekers who were admitted into common refugee housings and reception centres. This remains an important tool for early case detection in Germany. Another active case fi nding method that is a pillar of tuberculosis prevention and control is contact tracing, which allows for the early detection and treatment of infected or ill contacts of active tuberculosis cases.

However, most cases of tuberculosis in Germany still continue to be diagnosed through passive case fi nding. This includes many patients who were born abroad and then immigrated to Germany as the risk of developing active disease remains higher for a number of years after entry. Around a quarter of tuberculosis patients diagnosed in Germany were born in Germany. Most of them are older individuals who became infected with TB during the war or post-war years and develop active tuberculosis later in life.

Although tuberculosis in children remains rare in Germany, when present, it can lead to severe disease. Therefore, tuberculosis among children continues to require particular attention not only because of their vulnerability but also as an indicator of current transmission among the population.

This highlights the importance of maintaining continued vigilance against tuberculosis for all age groups and the consideration for diff erential diagnosis.

Complex drug resistances, which contribute to higher incidence of tuberculosis in population risk groups, as well as high proportions of infectious pulmonary tuberculosis demonstrate that tuberculosis is still a disease with signifi cant public health relevance in Germany.

Ensuring a timely diagnosis and treating patients with appropriate therapy regimes that take into account their resistances is crucial and requires the coordinated teamwork of all stakeholders involved. In particular, multidrug-resistant and extensively drug-resistant tuberculosis require competent case management by treatment providers and local health authorities. Successful tuberculosis control therefore requires well-trained doctors and a public health service with suffi cient resources. Additionally, a well-established tuberculosis surveillance system is needed, which, using the notifi ed data (including treatment outcome data), is capable of identifying current trends and changes in the epidemiological situation in Germany at an early stage and can place these developments in the context of their infl uencing factors.