Isoniazid resistance among tuberculosis patients by birth cohort in Germany

Germany, 1997-2000.

To determine the prevalence of isoniazid resistance by year of birth among previously treated and untreated tuberculosis patients by country of birth.

Univariate and multivariate analyses of data on 8658 cases from a nationally representative sample.

The crude prevalence of isoniazid resistance was 2.4% and 9.9% among Germany-born patients respectively without and with a prior treatment history. Among those without a history, there was virtually no difference between quartiles of birth cohorts, while among those with, a large decrease from the oldest to the youngest was observed. Among foreign-born patients, the prevalence of isoniazid resistance increased from 3.8% to 11.8% from the oldest to the youngest among those without, and more than doubled from less than 20% to more than 40% among those with prior treatment.

This analysis suggests a remarkably constant and low prevalence of isoniazid resistance among never treated Germany-born patients. In contrast, among the diverse group of foreign-born patients, the prevalence increases appreciably from the oldest to the youngest birth cohorts. This indicates that tuberculosis treatment policies in Germany have been sound and that great care is needed to prevent acquisition of additional resistance among foreign-born patients.